Update version

Closes #634

.config/dotnet-tools.json

@@ -0,0 +1,12 @@
+{
+  "version": 1,
+  "isRoot": true,
+  "tools": {
+    "xamlstyler.console": {
+      "version": "3.2003.9",
+      "commands": [
+        "xstyler"
+      ]
+    }
+  }
+}

.gitattributes

@@ -1,63 +0,0 @@
-###############################################################################
-# Set default behavior to automatically normalize line endings.
-###############################################################################
-* text=auto
-
-###############################################################################
-# Set default behavior for command prompt diff.
-#
-# This is need for earlier builds of msysgit that does not have it on by
-# default for csharp files.
-# Note: This is only used by command line
-###############################################################################
-#*.cs     diff=csharp
-
-###############################################################################
-# Set the merge driver for project and solution files
-#
-# Merging from the command prompt will add diff markers to the files if there
-# are conflicts (Merging from VS is not affected by the settings below, in VS
-# the diff markers are never inserted). Diff markers may cause the following 
-# file extensions to fail to load in VS. An alternative would be to treat
-# these files as binary and thus will always conflict and require user
-# intervention with every merge. To do so, just uncomment the entries below
-###############################################################################
-#*.sln       merge=binary
-#*.csproj    merge=binary
-#*.vbproj    merge=binary
-#*.vcxproj   merge=binary
-#*.vcproj    merge=binary
-#*.dbproj    merge=binary
-#*.fsproj    merge=binary
-#*.lsproj    merge=binary
-#*.wixproj   merge=binary
-#*.modelproj merge=binary
-#*.sqlproj   merge=binary
-#*.wwaproj   merge=binary
-
-###############################################################################
-# behavior for image files
-#
-# image files are treated as binary by default.
-###############################################################################
-#*.jpg   binary
-#*.png   binary
-#*.gif   binary
-
-###############################################################################
-# diff behavior for common document formats
-# 
-# Convert binary document formats to text before diffing them. This feature
-# is only available from the command line. Turn it on by uncommenting the 
-# entries below.
-###############################################################################
-#*.doc   diff=astextplain
-#*.DOC   diff=astextplain
-#*.docx  diff=astextplain
-#*.DOCX  diff=astextplain
-#*.dot   diff=astextplain
-#*.DOT   diff=astextplain
-#*.pdf   diff=astextplain
-#*.PDF   diff=astextplain
-#*.rtf   diff=astextplain
-#*.RTF   diff=astextplain

.github/FUNDING.yml

@@ -0,0 +1,3 @@
+github: Tyrrrz
+patreon: Tyrrrz
+custom: ['buymeacoffee.com/Tyrrrz', 'tyrrrz.me/donate']

.github/ISSUE_TEMPLATE/bug-report.yml

@@ -0,0 +1,64 @@
+name: 🐞 Bug report
+description: Report broken functionality.
+labels: [bug]
+
+body:
+- type: markdown
+  attributes:
+    value: |
+      🧐 **Guidelines:**
+
+      - Search through [existing issues](https://github.com/Tyrrrz/DiscordChatExporter/issues?q=is%3Aissue) first to ensure that this bug has not been reported before.
+      - Write a descriptive title for your issue. Avoid generic or vague titles such as "Something's not working" or "A couple of problems".
+      - Keep your issue focused on one single problem. If you have multiple bug reports, please create separate issues for each of them.
+      - Provide as much context as possible in the details section. Include screenshots, screen recordings, links, references, or anything else you may consider relevant.
+      - If you want to ask a question instead of reporting a bug, please use [discussions](https://github.com/Tyrrrz/DiscordChatExporter/discussions/new) instead.
+
+- type: input
+  attributes:
+    label: Version
+    description: Which version of DiscordChatExporter does this bug affect?
+    placeholder: ver X.Y.Z
+  validations:
+    required: true
+
+- type: dropdown
+  attributes:
+    label: Flavor
+    description: Does this bug affect the GUI version, the CLI version, or both?
+    multiple: true
+    options:
+    - GUI (Graphical User Interface)
+    - CLI (Command Line Interface)
+  validations:
+    required: true
+
+- type: dropdown
+  attributes:
+    label: Export format
+    description: Does this bug affect specific export format(s)? If not applicable, leave this field blank.
+    multiple: true
+    options:
+    - HTML
+    - TXT
+    - JSON
+    - CSV
+
+- type: textarea
+  attributes:
+    label: Details
+    description: Clear and thorough explanation of the bug.
+    placeholder: I was doing X expecting Y to happen, but Z happened instead.
+  validations:
+    required: true
+
+- type: textarea
+  attributes:
+    label: Steps to reproduce
+    description: Minimum steps required to reproduce the bug.
+    placeholder: |
+      - Step 1
+      - Step 2
+      - Step 3
+  validations:
+    required: true

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,8 @@
+blank_issues_enabled: false
+contact_links:
+  - name: 📖 Wiki
+    url: https://github.com/Tyrrrz/DiscordChatExporter/wiki
+    about: Find usage guides and frequently asked questions.
+  - name: 🗨 Discussions
+    url: https://github.com/Tyrrrz/DiscordChatExporter/discussions/new
+    about: Ask and answer questions.

.github/ISSUE_TEMPLATE/feature-request.yml

@@ -0,0 +1,42 @@
+name: ✨ Feature request
+description: Request a new feature.
+labels: [enhancement]
+
+body:
+- type: markdown
+  attributes:
+    value: |
+      🧐 **Guidelines:**
+
+      - Search through [existing issues](https://github.com/Tyrrrz/DiscordChatExporter/issues?q=is%3Aissue) first to ensure that this feature has not been requested before.
+      - Write a descriptive title for your issue. Avoid generic or vague titles such as "Some suggestions" or "Ideas for improvement".
+      - Keep your issue focused on one single problem. If you have multiple feature requests, please create separate issues for each of them.
+      - Provide as much context as possible in the details section. Include screenshots, screen recordings, links, references, or anything else you may consider relevant.
+      - If you want to ask a question instead of requesting a feature, please use [discussions](https://github.com/Tyrrrz/DiscordChatExporter/discussions/new) instead.
+
+- type: dropdown
+  attributes:
+    label: Flavor
+    description: Is this feature request related to specific flavor(s) of DiscordChatExporter? If not applicable, leave this field blank.
+    multiple: true
+    options:
+    - GUI (Graphical User Interface)
+    - CLI (Command Line Interface)
+
+- type: dropdown
+  attributes:
+    label: Export format
+    description: Is this feature request related to specific export format(s)? If not applicable, leave this field blank.
+    multiple: true
+    options:
+    - HTML
+    - TXT
+    - JSON
+    - CSV
+
+- type: textarea
+  attributes:
+    label: Details
+    description: Clear and thorough explanation of the feature you have in mind.
+  validations:
+    required: true

.github/PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,17 @@
+<!--
+
+**Important:**
+
+Please make sure that there is an existing issue that describes the problem solved by your pull request. If there isn't one, consider creating it first.
+An open issue offers a good place to iron out requirements, discuss possible solutions, and ask questions.
+
+Remember to also:
+
+- Keep your pull request focused and as small as possible. If you want to contribute multiple unrelated changes, please create separate pull requests for them.
+- Follow the coding style and conventions already established by the project. When in doubt about which style to use, ask in the comments to your pull request.
+- If you want to start a discussion regarding a specific change you've made, add a review comment to your own code. This can be used to highlight something important or to seek further input from others.
+
+-->
+
+<!-- Please specify the issue addressed by this pull request -->
+Closes #ISSUE_NUMBER

.github/workflows/CD.yml

@@ -0,0 +1,71 @@
+name: CD
+
+on:
+  push:
+    tags:
+      - "*"
+
+jobs:
+  build:
+    runs-on: windows-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.3
+
+      - name: Install .NET (v3.1)
+        uses: actions/setup-dotnet@v1.7.2
+        with:
+          dotnet-version: 3.1.x
+
+      - name: Install .NET (v5.0)
+        uses: actions/setup-dotnet@v1.7.2
+        with:
+          dotnet-version: 5.0.x
+
+      - name: Build & publish (CLI)
+        run: dotnet publish DiscordChatExporter.Cli/ -o DiscordChatExporter.Cli/bin/Publish/ --configuration Release
+
+      - name: Build & publish (GUI)
+        run: dotnet publish DiscordChatExporter.Gui/ -o DiscordChatExporter.Gui/bin/Publish/ --configuration Release
+
+      - name: Pack (CLI)
+        run: Compress-Archive -Path DiscordChatExporter.Cli/bin/Publish/* -DestinationPath DiscordChatExporter.Cli/bin/Publish/Archive.zip -Force
+        shell: pwsh
+
+      - name: Pack (GUI)
+        run: Compress-Archive -Path DiscordChatExporter.Gui/bin/Publish/* -DestinationPath DiscordChatExporter.Gui/bin/Publish/Archive.zip -Force
+        shell: pwsh
+
+      - name: Create release
+        id: create_release
+        uses: actions/create-release@v1.0.1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          tag_name: ${{ github.ref }}
+          release_name: ${{ github.ref }}
+          body: |
+            [Changelog](https://github.com/Tyrrrz/DiscordChatExporter/blob/master/Changelog.md)
+          draft: false
+          prerelease: false
+
+      - name: Upload release asset (CLI)
+        uses: actions/upload-release-asset@v1.0.2
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: DiscordChatExporter.Cli/bin/Publish/Archive.zip
+          asset_name: DiscordChatExporter.CLI.zip
+          asset_content_type: application/zip
+
+      - name: Upload release asset (GUI)
+        uses: actions/upload-release-asset@v1.0.2
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ steps.create_release.outputs.upload_url }}
+          asset_path: DiscordChatExporter.Gui/bin/Publish/Archive.zip
+          asset_name: DiscordChatExporter.zip
+          asset_content_type: application/zip

.github/workflows/CI.yml

@@ -0,0 +1,39 @@
+name: CI
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: windows-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2.3.3
+
+      - name: Install .NET (v3.1)
+        uses: actions/setup-dotnet@v1.7.2
+        with:
+          dotnet-version: 3.1.x
+
+      - name: Install .NET (v5.0)
+        uses: actions/setup-dotnet@v1.7.2
+        with:
+          dotnet-version: 5.0.x
+
+      - name: Build & publish (CLI)
+        run: dotnet publish DiscordChatExporter.Cli/ -o DiscordChatExporter.Cli/bin/Publish/ --configuration Release
+
+      - name: Build & publish (GUI)
+        run: dotnet publish DiscordChatExporter.Gui/ -o DiscordChatExporter.Gui/bin/Publish/ --configuration Release
+
+      - name: Upload build artifacts (CLI)
+        uses: actions/upload-artifact@v1
+        with:
+          name: DiscordChatExporter.CLI
+          path: DiscordChatExporter.Cli/bin/Publish/
+
+      - name: Upload build artifact (GUI)
+        uses: actions/upload-artifact@v1
+        with:
+          name: DiscordChatExporter
+          path: DiscordChatExporter.Gui/bin/Publish/

.gitignore

@@ -1,261 +1,22 @@
-## Ignore Visual Studio temporary files, build results, and
-## files generated by popular Visual Studio add-ons.
-
 # User-specific files
 *.suo
 *.user
 *.userosscache
 *.sln.docstates
-
-# User-specific files (MonoDevelop/Xamarin Studio)
-*.userprefs
+.idea/
+.vs/
 
 # Build results
 [Dd]ebug/
 [Dd]ebugPublic/
 [Rr]elease/
 [Rr]eleases/
-x64/
-x86/
+[Xx]64/
+[Xx]86/
+[Bb]uild/
 bld/
 [Bb]in/
 [Oo]bj/
-[Ll]og/
 
-# Visual Studio 2015 cache/options directory
-.vs/
-# Uncomment if you have tasks that create the project's static files in wwwroot
-#wwwroot/
-
-# MSTest test Results
-[Tt]est[Rr]esult*/
-[Bb]uild[Ll]og.*
-
-# NUNIT
-*.VisualState.xml
-TestResult.xml
-
-# Build Results of an ATL Project
-[Dd]ebugPS/
-[Rr]eleasePS/
-dlldata.c
-
-# DNX
-project.lock.json
-project.fragment.lock.json
-artifacts/
-
-*_i.c
-*_p.c
-*_i.h
-*.ilk
-*.meta
-*.obj
-*.pch
-*.pdb
-*.pgc
-*.pgd
-*.rsp
-*.sbr
-*.tlb
-*.tli
-*.tlh
-*.tmp
-*.tmp_proj
-*.log
-*.vspscc
-*.vssscc
-.builds
-*.pidb
-*.svclog
-*.scc
-
-# Chutzpah Test files
-_Chutzpah*
-
-# Visual C++ cache files
-ipch/
-*.aps
-*.ncb
-*.opendb
-*.opensdf
-*.sdf
-*.cachefile
-*.VC.db
-*.VC.VC.opendb
-
-# Visual Studio profiler
-*.psess
-*.vsp
-*.vspx
-*.sap
-
-# TFS 2012 Local Workspace
-$tf/
-
-# Guidance Automation Toolkit
-*.gpState
-
-# ReSharper is a .NET coding add-in
-_ReSharper*/
-*.[Rr]e[Ss]harper
-*.DotSettings.user
-
-# JustCode is a .NET coding add-in
-.JustCode
-
-# TeamCity is a build add-in
-_TeamCity*
-
-# DotCover is a Code Coverage Tool
-*.dotCover
-
-# NCrunch
-_NCrunch_*
-.*crunch*.local.xml
-nCrunchTemp_*
-
-# MightyMoose
-*.mm.*
-AutoTest.Net/
-
-# Web workbench (sass)
-.sass-cache/
-
-# Installshield output folder
-[Ee]xpress/
-
-# DocProject is a documentation generator add-in
-DocProject/buildhelp/
-DocProject/Help/*.HxT
-DocProject/Help/*.HxC
-DocProject/Help/*.hhc
-DocProject/Help/*.hhk
-DocProject/Help/*.hhp
-DocProject/Help/Html2
-DocProject/Help/html
-
-# Click-Once directory
-publish/
-
-# Publish Web Output
-*.[Pp]ublish.xml
-*.azurePubxml
-# TODO: Comment the next line if you want to checkin your web deploy settings
-# but database connection strings (with potential passwords) will be unencrypted
-#*.pubxml
-*.publishproj
-
-# Microsoft Azure Web App publish settings. Comment the next line if you want to
-# checkin your Azure Web App publish settings, but sensitive information contained
-# in these scripts will be unencrypted
-PublishScripts/
-
-# NuGet Packages
-*.nupkg
-# The packages folder can be ignored because of Package Restore
-**/packages/*
-# except build/, which is used as an MSBuild target.
-!**/packages/build/
-# Uncomment if necessary however generally it will be regenerated when needed
-#!**/packages/repositories.config
-# NuGet v3's project.json files produces more ignoreable files
-*.nuget.props
-*.nuget.targets
-
-# Microsoft Azure Build Output
-csx/
-*.build.csdef
-
-# Microsoft Azure Emulator
-ecf/
-rcf/
-
-# Windows Store app package directories and files
-AppPackages/
-BundleArtifacts/
-Package.StoreAssociation.xml
-_pkginfo.txt
-
-# Visual Studio cache files
-# files ending in .cache can be ignored
-*.[Cc]ache
-# but keep track of directories ending in .cache
-!*.[Cc]ache/
-
-# Others
-ClientBin/
-~$*
-*~
-*.dbmdl
-*.dbproj.schemaview
-*.jfm
-*.pfx
-*.publishsettings
-node_modules/
-orleans.codegen.cs
-
-# Since there are multiple workflows, uncomment next line to ignore bower_components
-# (https://github.com/github/gitignore/pull/1529#issuecomment-104372622)
-#bower_components/
-
-# RIA/Silverlight projects
-Generated_Code/
-
-# Backup & report files from converting an old project file
-# to a newer Visual Studio version. Backup files are not needed,
-# because we have git ;-)
-_UpgradeReport_Files/
-Backup*/
-UpgradeLog*.XML
-UpgradeLog*.htm
-
-# SQL Server files
-*.mdf
-*.ldf
-
-# Business Intelligence projects
-*.rdl.data
-*.bim.layout
-*.bim_*.settings
-
-# Microsoft Fakes
-FakesAssemblies/
-
-# GhostDoc plugin setting file
-*.GhostDoc.xml
-
-# Node.js Tools for Visual Studio
-.ntvs_analysis.dat
-
-# Visual Studio 6 build log
-*.plg
-
-# Visual Studio 6 workspace options file
-*.opt
-
-# Visual Studio LightSwitch build output
-**/*.HTMLClient/GeneratedArtifacts
-**/*.DesktopClient/GeneratedArtifacts
-**/*.DesktopClient/ModelManifest.xml
-**/*.Server/GeneratedArtifacts
-**/*.Server/ModelManifest.xml
-_Pvt_Extensions
-
-# Paket dependency manager
-.paket/paket.exe
-paket-files/
-
-# FAKE - F# Make
-.fake/
-
-# JetBrains Rider
-.idea/
-*.sln.iml
-
-# CodeRush
-.cr/
-
-# Python Tools for Visual Studio (PTVS)
-__pycache__/
-*.pyc
+# Coverage
+*.opencover.xml

Changelog.md

@@ -1,14 +1,240 @@
+### v2.29 (19-Jul-2021)
+
+- Added support for message filtering, which is accessible as an additional export parameter in the GUI and as the `--filter` option in the CLI. Message filters use a special syntax similar to Discord's search query syntax to allow specifying which messages should be included in the export. For example, you can limit the export to only include messages that contain image attachments (`has:image`) or messages from a certain user (`from:Tyrrrz`) or messages containing certain words (`hello world`), etc. You can also combine filters together (`hi mentions:Tyrrrz`, `from:Tyrrrz | from:96-LB`, `(mentions:Tyrrrz | from:Tyrrrz) has:image`) or negate them (`-has:link`). More thorough documentation coming soon. (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+- Added support for rendering mentions of voice channels, in addition to text channels.
+- Added support for rendering unix timestamp markers. Currently, style markers are ignored and timestamps are always rendered with the format configured in settings (or provided via `--date-format` option).
+- Updated in-app instructions for obtaining a user token. (Thanks [@Yudi](https://github.com/Yudi) and [@virtuallyvlad](https://github.com/virtuallyvlad))
+- [HTML] Improved visual appearance of the reference symbol (Г-shaped line in replies) to make it more closely resemble Discord's styling.
+- [HTML] Added more specific fallback text used when rendering referenced messages that contain no text content but have attachments or embeds.
+- [HTML] Fixed an issue where a broken embed author icon occupied visual space, ruining the embed layout. (Thanks [@Cliff J.](https://github.com/CliffJameston))
+- [GUI] Improved handling for fatal errors that may occur when attempting to export a channel. These errors are now displayed in a popup, allowing the user to try again instead of having the application crash completely.
+- [CLI] Fixed an issue where an attempt to export a channel resulted in `NotSupportedException` when the default encoding was set to `UTF8`.
+- [CLI] Fixed an issue where providing an incorrectly formatted partition limit via `-p|--partition` option resulted in a non-descriptive and unhelpful error.
+- Improved "Requested resource does not exist" error message by including the ID of the requested resource.
+
+### v2.28 (19-Jun-2021)
+
+- [HTML] Added special casing for YouTube video embeds to render them directly using an embedded player. (Thanks [@quentinmay](https://github.com/quentinmay))
+- [HTML] Added support for rendering standard emoji by code. Such emoji may sometimes be found in messages sent by bots or through webhooks. (Thanks [@CanePlayz](https://github.com/CanePlayz) and [@Lucas LaBuff](https://github.com/96-LB))
+- [HTML] Changed tooltips on standard emoji to show emoji code instead of their raw string representations. (Thanks [@CanePlayz](https://github.com/CanePlayz) and [@Lucas LaBuff](https://github.com/96-LB))
+- [HTML] Added tooltips on individual messages to show when those messages were sent. 
+- [HTML] Updated colors and minor styling elements to match Discord's new style direction after rebranding.
+- [HTML] Updated Twemoji URLs to use SVG image variants for better rendering quality.
+- [HTML] Changed user avatar URLs to include predetermined size query parameter for better rendering quality.
+- Changed embed rendering logic to prefer Discord-proxied URLs for external content, in order to avoid unnecessary HTTP requests to third parties.
+- Fixed an issue where exporting with media sometimes resulted in a crash due to lack of permissions to change file attributes. These errors are now ignored, which means that the creation, write, and access dates of downloaded files may sometimes not match the dates provided by Discord's CDN.
+- [HTML] Fixed styling issues when rendering embed footers.
+- [HTML] Fixed an issue where links didn't render properly inside referenced messages.
+- [HTML] Fixed an issue where standalone emoji were incorrectly enlarged inside referenced messages.
+- [HTML] Fixed an issue where clicking on a referenced message revealed spoilers inside of it.
+- [GUI] Fixed an issue where the list of missing components, reported by the prerequisite check at application startup, included Windows updates that were not applicable to the user's system due to the fact that other superseding updates have already been installed. This issue only affected users running DiscordChatExporter on Windows 7.
+- [GUI] Fixed a few other minor issues related to the prerequisite installation window.
+
+### v2.27.1 (08-Jun-2021)
+
+- [GUI] Application will now detect if the required .NET Runtime or any of its prerequisites are missing and prompt the user to download and install them automatically. **Experimental feature, please test it out and report any issues you may find!**
+- [CLI] Fixed an issue where the application crashed when exporting a channel that had square brackets as part of its name or category name. (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+
+### v2.27 (24-Apr-2021)
+
+- Added partitioning by file size. You can now use values such as `10mb` to indicate a size-based cut off point, in addition to values like `10` to indicate a number of messages. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- [CLI] Improved formatting and progress reporting.
+- [CLI] Changed `export` command so that it can accept multiple channel IDs passed to `-c|--channel` option. This makes it possible to export multiple channels at once while benefiting from parallelization.
+- [JSON] Added `color` field to message author. This is a hex string that represents user's color, inherited from their roles. (Thanks [@rtm516](https://github.com/rtm516))
+- [JSON] Added `categoryId` field to the root. This represents the ID of the category channel that the currently exported channel belongs to. (Thanks [@rtm516](https://github.com/rtm516))
+- [JSON] Fixed an issue where user discriminator was written without leading zeroes. (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+- [JSON] Fixed an issue where the application sometimes crashed with an error saying `']' invalid without a matching open`, which was just a validation message that masked the actual error behind the failure. (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+- Fixed an issue where progress was not reported correctly if the channel didn't have any messages in the specified time range.
+
+### v2.26.1 (06-Feb-2021)
+
+- [CLI] Added support for file name templates, which allow you to dynamically generate output file names based on channel and guild metadata. (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+- Fixed an issue where the application sometimes crashed with `Invalid snowflake` message when exporting chat logs that contained invalid or outdated mentions. (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+
+### v2.26 (29-Dec-2020)
+
+- [HTML] Added support for replies. (Thanks [@Sanqui](https://github.com/Sanqui))
+- [HTML] Improved styling of non-media attachments (regular files, i.e. not video, audio, or image). (Thanks [@Lucas LaBuff](https://github.com/96-LB))
+- [HTML] Improved initial export performance.
+- [JSON] Relaxed escaping rules for unicode characters. (Thanks [@Sanqui](https://github.com/Sanqui))
+- [JSON] Added support for replies. (Thanks [@Sanqui](https://github.com/Sanqui))
+- [CLI] Added channel names to errors shown on failures when exporting multiple channels. (Thanks [@Sanqui](https://github.com/Sanqui))
+- [CLI] Added support for passing message IDs (snowflakes) to `--after` and `--before` options. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- Files downloaded by the "download referenced media" option now have their dates set according to the `Last-Modified` header provided by Discord CDN. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- Fixed an issue where the application sometimes crashed with `NullReferenceException` when retrying a failed HTTP request.
+- Migrated to Discord API v8.
+
+### v2.25 (23-Nov-2020)
+
+- [JSON] Added `mentions` property to the output. This contains users referenced inside the message text, but doesn't include mentions in embeds. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- [HTML] Added better previews for attached video and audio. They are now rendered using a browser native player element. The actual file path can still be retrieved by right clicking and selecting "Copy file path". (Thanks [@sas41](https://github.com/sas41))
+- [CLI] Fixed an issue where using `--media` option without providing a rooted path via `--output` option triggered an error.
+- [CLI] Fixed an issue where using `--reuse-media` option without also providing `--media` option was accepted, but didn't actually do anything. Now this produces an error instead. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+
+### v2.24 (24-Oct-2020)
+
+- [CLI] Updated to [CliFx v1.5](https://github.com/Tyrrrz/CliFx), which brings some UX improvements.
+- [GUI] Added dark mode, which can be enabled in settings. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- [GUI] Improved the UX in a few minor places.
+- [JSON] Added `embed.color` property to the output. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- Added additional date formats: `unix` to write dates as a unix timestamp and `unixms` for the milliseconds version. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- Added retry policy for downloading media content. This is mostly a workaround for transient failures that sometimes may occur when downloading assets referenced from embeds. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+- Added an option to reuse already downloaded media to avoid redundant network requests. It can be enabled in settings in GUI, or by passing `--reuse-media` in CLI. To facilitate this feature, the file name strategy has been changed as well -- now instead of relying on the original file name and adding `(n)` to the end in case of duplicates, a URL hash is injected in every file name. This also means that when the "reuse media" option is disabled, existing files inside the media directory may be overwritten. (Thanks [@Andrew Kolos](https://github.com/andrewkolos))
+
+### v2.23 (14-Sep-2020)
+
+- [CLI] Added a command to export all channels across all servers. Use `exportall` to do it. (Thanks [@wyattscarpenter](https://github.com/wyattscarpenter))
+- [HTML] Fixed an issue where Whitney fonts were not being loaded properly, causing the browser to fall back to Helvetica.
+- Fixed an issue where self-contained export crashed occasionally. This usually happened when the server hosting the file did not serve the stream properly. Such files are now ignored after the first failed attempt.
+
+### v2.22 (12-Aug-2020)
+
+- [GUI] Improved the channel list by adding collapsible category groups. (Thanks [@CarJem Generations](https://github.com/CarJem))
+- [GUI] Improved exporting options by adding a set of controls that can be used to limit the date range of the export down to minutes. Previously it was only possible to configure the date range without the time component. (Thanks [@CarJem Generations](https://github.com/CarJem))
+- [HTML] Fixed an issue where the export didn't reflect changes in nicknames between messages sent by bots. This affected chat logs that contained interactions with the Tupperbox bot. (Thanks [@CarJem Generations](https://github.com/CarJem))
+- [CLI] Fixed an issue where the application crashed if there were two environment variables defined that had the same name but in different case.
+
+### v2.21.2 (30-Jul-2020)
+
+- [GUI] When copy-pasting token, any surrounding spaces are now discarded, in addition to double quotes.
+- [HTML] Changed underlying templating engine to provide higher performance and better error messages. New templating engine adds a small cold start, but any export after the first should be faster.
+- Changed naming schema for downloaded media so that it follows `<original filename> (nn)` format rather than `<original filename>-salt`.
+- [HTML] Fixed an issue where downloaded media was sometimes inaccessible due to reserved characters appearing in the URL.
+- Fixed an issue where the application crashed when trying to download media with a file name that exceeds system's maximum allowed length.
+- Fixed an issue where the application crashed when trying to download media with illegal characters in the file name.
+
+### v2.21.1 (19-Jul-2020)
+
+- Fixed an issue where the export crashed if an embedded image has been deleted. Such media files are now ignored.
+- Changed the naming convention for downloaded media files so that the original file names are used when possible.
+
+### v2.21 (18-Jul-2020)
+
+- Added a new option that enables self-contained exports for all output formats. You can turn it on in the export setup dialog in GUI or using the `--media` option in CLI. When using this, the application will additionally download any media content directly referenced from the exported file instead of linking back to Discord CDN. The files which are downloaded include: guild icons, user avatars, attachments, embedded images, reaction emoji. Note that only files which are actually referenced by the export are downloaded, which means that, for example, user avatars will not be downloaded when using plain text export format. This option is not meant to enable complete offline viewing for HTML exports, but rather to make it easier to archive media content that may eventually get deleted from Discord servers. Also keep in mind that this option may make the export drastically slower and the total file size larger.
+- Changed "discordapp.com" to "discord.com" where applicable as Discord is migrating to a new domain. CDN will remain on "cdn.discordapp.com" for the foreseeable future.
+
+Note that all existing and current HTML exports will likely not render accurately because Discord enabled CORS for their font resources, which prevents them from loading locally. Please refer to [issue #322](https://github.com/Tyrrrz/DiscordChatExporter/issues/322) for discussion on this topic. 
+
+### v2.20 (27-Apr-2020)
+
+- [CLI] Added environment variables as fallback for `--token` and `--bot` options. They are `DISCORD_TOKEN` and `DISCORD_TOKEN_BOT` respectively.
+- [GUI] Fixed a crash that occurred if the application was closed in the middle of an auto-update.
+- [GUI] Added a link to project's wiki in the usage guide.
+- [HTML] Added full spoiler support for text and images. To spoil the hidden content you now need to click on it, similarly to how it works in Discord. (Thanks [@FM-96](https://github.com/FM-96))
+- [HTML] Updated grammar for consecutive single-line quotes. Previously they appeared separately, now they're grouped together as if it was one multi-line quote instead.
+- [HTML] Fixed an issue where messages sent by the same bot but with different usernames were grouped together when they shouldn't be.
+- [HTML] Updated grammar for single-line code blocks to accept double backticks as synonymous with single backticks. This change makes code blocks appear the same, whether they were inserted manually or using Discord's buggy markdown preview mode.
+- [HTML] Fixed styling inconsistencies and other minor issues.
+- [TXT/JSON] Fixed an issue where markdown was not parsed correctly in embed fields.
+- [HTML] Changed markdown formatting in embeds so it follows the same set of rules as in Discord.
+- Added channel category to the default file name used when exporting chat logs.
+- [HTML/TXT/JSON] Added channel category to exported metadata.
+- [CLI] Updated commands to also show channel category as well as channel name wherever relevant.
+- Starting with this release, Docker images will have new tags: `stable` for latest stable release and `2.20` for a specific version.
+
+### v2.19 (26-Mar-2020)
+
+- Added parallel exporting. This option allows you to export multiple channels faster by doing it in parallel. You can configure the parallel limit in settings (GUI) or with the `--parallel` option (CLI). Default value is `1`, which means there is no parallelization. Warning: be careful when using this option, as this will result in higher volume of concurrent HTTP requests sent to Discord, which might get you flagged. Use at your own risk.
+- [HTML] Added support for user colors. User names are now appropriately colored according to the assigned guild roles.
+- [HTML] Added support for nicknames. User names are replaced with nicknames where it's applicable. It's still possible to see the full user name by hovering your mouse over the nickname.
+- [HTML] Improved styling for mentions to bring it more in line with how it looks in Discord.
+
+### v2.18 (04-Feb-2020)
+
+- Added JSON export format. It's a structured data format which is easy to parse. If you're using DiscordChatExporter to export chat logs for further ingestion by another tool, this is most likely the format you will want to use.
+- [GUI] You can now quickly jump to a specific channel in a list. For example, if you want to jump to a channel named "General", you can simply press the 'g' key in the channel list view. You can also press 'g', 'e' and 'n' in quick succession which will jump to the next channel that starts with "gen". This mechanic is consistent with other Windows applications.
+- [CLI] Improved help text screen.
+
+### v2.17 (12-Jan-2020)
+
+- Fixed an issue where an empty file was produced when exporting a channel with no messages (for specified period). With the new behavior, no file will be created and instead a message will be shown to the user informing of the failure.
+- [HTML/TXT] Added message count to the bottom of the file. This number shows how many messages were exported as part of the current file. Prior to 2.16 this number was present along with the rest of the metadata at the top, then removed due to changes in the exporter, and now brought back at the end of the file instead.
+- [HTML] Fixed an issue where some emoji were not properly rendered.
+- [GUI] Added a setting that lets you configure whether to remember the last used token. Previously it was the default behavior, but now you can disable it if you don't want the token persisted on your system.
+
+### v2.16 (08-Dec-2019)
+
+- Migrated from .NET Framework to .NET Core. To run this and future versions of DiscordChatExporter you will need [.NET Core runtime for desktop apps](https://dotnet.microsoft.com/download/dotnet-core/3.1/runtime) (for GUI/CLI version on Windows) or [.NET Core base runtime](https://dotnet.microsoft.com/download/dotnet-core/3.1) (for CLI version on Windows, Linux or macOS).
+- Reworked the exporter engine to render output using streaming data source. This means that only a very small portion of messages are cached in memory when exporting. In other words, you are only limited by storage space and not how much RAM you have, so you can now export terabytes of chat logs without hitting out of memory exceptions. I still recommend using partitions if you're exporting very large chat logs (250k+ messages) to HTML, unless you want your computer to catch fire when you try to open the export in browser.
+- Changed how partitioned files are named, due to the fact that total number of partitions is no longer known ahead of time.
+- Added a warning about automating user accounts to the usage guide in both GUI and CLI versions.
+- Added support for announcement (news) channels. You will now be able to see them in the list and export them.
+- Fixed various issues that resulted in exceptions during export process.
+- [HTML/TXT] Removed message count from the metadata. Due to the fact that the messages are exported as they are streamed, total number of messages is not known ahead of time.
+- [HTML] Changed default color of the embed color pill to match the theme.
+- [HTML] Changed emoji parser to be less greedy. As a result it should match fewer character sequences that look like emoji but really aren't, but on the other hand it might miss some actual emoji. This means that some standard emoji (i.e. not custom server emoji) may not look like in Discord. This is a compromise I'm willing to take because detecting emoji in text is really hard to get right and not worth it at all.
+- [HTML] Some other minor styling adjustments.
+- [CSV] Replaced semicolons (;) with (,) as separators.
+
+Please note that CSV export is most likely not going to receive future updates and will remain only as an option for those who wish to use it for text analysis. In other words, it won't contain any of the rich media features like embeds. If you're currently using CSV as a structured output to feed into your program, JSON output will replace that in the future.
+
+### v2.15 (15-Sep-2019)
+
+- Improved markdown parser and made it even faster for non-HTML formats.
+- [HTML] Added support for block quotes.
+- [HTML] Links pointing to a Discord message will now navigate to the linked message inside exported chat log if it's there.
+- [HTML] Updated light theme to match how it looks in Discord after recent changes.
+- [HTML] Added indication for when a message is pinned. Pinned messages now have a tinted background.
+- [HTML] Fixed an issue where multiline code blocks sometimes had incorrect formatting applied to them.
+- [TXT] Added indication for when a message is pinned. Pinned messages now have `(pinned)` next to timestamp and author.
+- [CSV] Added message author's user ID to output.
+- [GUI] Streamlined auto-update process a bit.
+- [GUI] Added some tooltips.
+
+### v2.14 (15-Jun-2019)
+
+- [TXT] Added support for embeds.
+- [TXT] Added support for reactions.
+- [CSV] Added support for reactions.
+- [TXT] Changed how attachments are rendered.
+
+### v2.13.1 (06-Jun-2019)
+
+- Fixed an issue where the app sometimes crashed when exporting due to `System.InvalidCastException`.
+- [HTML] Added `data-user-id` attribute to `span.chatlog__author-name`. The value of this attribute is author's Discord user ID.
+
+### v2.13 (15-May-2019)
+
+- Updated usage instructions.
+- [HTML] Added BOT tags to messages posted by bots.
+- [GUI] UI will now be disabled when exporting.
+- [GUI] Notification informing that the export has completed will now appear after all exports have completed, instead of each of them separately.
+
+### v2.12.1 (12-Apr-2019)
+
+- [GUI] Fixed an issue where the app crashed when trying to export multiple channels.
+- [HTML] Fixed an issue where some of the emoji were rendered via Twemoji while Discord renders them as plain text.
+- [HTML] Fixed an issue where emoji weren't jumbo if there were more than one of them.
+
+### v2.12 (11-Apr-2019)
+
+- Improved markdown parsing performance which speeds up the final stage of exporting by around 4.5 times.
+- Improved performance when exporting as PlainText or CSV.
+- [GUI] Fixed an issue where the app would freeze up and report as "not responding" during the final stage of exporting.
+- [CLI] Fixed an issue where it would say "Completed" after exporting a chat log, even if the process failed.
+
+### v2.11 (14-Mar-2019)
+
+- [HTML] Added syntax highlighting for multiline code blocks via Highlight.js.
+- Added retry policy for all 5xx status codes to prevent random crashes.
+
+### v2.10.2 (10-Mar-2019)
+
+- [HTML] Updated message grouping algorithm to make it the same as in Discord. Removed "message group limit" setting and parameter.
+- [HTML] Added small margin at the end of the chatlog so it doesn't look like it was truncated.
+- [CLI] Fixed an issue where the app would crash if stdout was redirected. Progress will not be reported in such cases.
+
 ### v2.10.1 (06-Mar-2019)
 
-- [HTML] Fixed an issue where multiple emojis on a single line would get rendered as one emoji.
+- [HTML] Fixed an issue where multiple emoji on a single line would get rendered as one emoji.
 - [HTML] Fixed an issue where an open square bracket character would incorrectly render as an emoji.
 - [HTML] Added alt text to emoji images so that they will be rendered using default font when Twemoji images are not available.
 
 ### v2.10 (03-Mar-2019)
 
 - [HTML] Reworked the entire markdown parsing engine which fixes numerous rendering inconsistencies (over 15 issues fixed).
-- [HTML] Added support for animated emojis.
-- [HTML] Standard emojis are now rendered using Twemoji, the same image set that Discord uses.
+- [HTML] Added support for animated emoji.
+- [HTML] Standard emoji are now rendered using Twemoji, the same image set that Discord uses.
 - [HTML] Fixed an issue where video attachments would render incorrectly.
 - [HTML] Minor fixes in styling.
 - [GUI] Aggregated export progress is now shown in the taskbar.
@@ -68,7 +294,7 @@
 - Added support for reactions (HTML only).
 - Selected date range is now shown in the export (HTML and PlainText).
 - Added placeholders for guild icons to display while the icons are loading.
-- Added support for jumbo emojis (custom emojis only).
+- Added support for jumbo emoji (custom emoji only).
 - Added basic retry policy for 429 error responses.
 - Added validation for from/to dates in the UI which prevents choosing invalid date ranges.
 - Added an error message when trying to export a deleted channel.
@@ -92,7 +318,7 @@
 
 - Improved message date filtering, it's now marginally faster.
 - Fixed underscores not recognized as italics in markdown.
-- Added support for custom emojis.
+- Added support for custom emoji.
 - Added support for user and role mentions.
 - Added support for channel mentions.
 - Fixed text in pre blocks not being wrapped correctly.

Deploy/Prepare.ps1

@@ -1,13 +0,0 @@
-New-Item "$PSScriptRoot\bin" -ItemType Directory -Force
-
-# GUI
-$files = @()
-$files += Get-Item -Path "$PSScriptRoot\..\License.txt"
-$files += Get-ChildItem -Path "$PSScriptRoot\..\DiscordChatExporter.Gui\bin\Release\*" -Include "*.exe", "*.dll", "*.config"
-$files | Compress-Archive -DestinationPath "$PSScriptRoot\bin\DiscordChatExporter.zip" -Force
-
-# CLI
-$files = @()
-$files += Get-Item -Path "$PSScriptRoot\..\License.txt"
-$files += Get-ChildItem -Path "$PSScriptRoot\..\DiscordChatExporter.Cli\bin\Release\net461\*" -Include "*.exe", "*.dll", "*.config"
-$files | Compress-Archive -DestinationPath "$PSScriptRoot\bin\DiscordChatExporter.CLI.zip" -Force

Directory.Build.props

@@ -0,0 +1,13 @@
+<Project>
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+    <Version>2.29</Version>
+    <Company>Tyrrrz</Company>
+    <Copyright>Copyright (c) Alexey Golub</Copyright>
+    <LangVersion>preview</LangVersion>
+    <Nullable>enable</Nullable>
+    <WarningsAsErrors>nullable</WarningsAsErrors>
+  </PropertyGroup>
+
+</Project>

DiscordChatExporter.Cli/Commands/Base/ExportCommandBase.cs

@@ -0,0 +1,148 @@
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Exceptions;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Utils.Extensions;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Exceptions;
+using DiscordChatExporter.Core.Exporting;
+using DiscordChatExporter.Core.Exporting.Filtering;
+using DiscordChatExporter.Core.Exporting.Partitioning;
+using DiscordChatExporter.Core.Utils.Extensions;
+using Tyrrrz.Extensions;
+
+namespace DiscordChatExporter.Cli.Commands.Base
+{
+    public abstract class ExportCommandBase : TokenCommandBase
+    {
+        [CommandOption("output", 'o', Description = "Output file or directory path.")]
+        public string OutputPath { get; init; } = Directory.GetCurrentDirectory();
+
+        [CommandOption("format", 'f', Description = "Export format.")]
+        public ExportFormat ExportFormat { get; init; } = ExportFormat.HtmlDark;
+
+        [CommandOption("after", Description = "Only include messages sent after this date or message ID.")]
+        public Snowflake? After { get; init; }
+
+        [CommandOption("before", Description = "Only include messages sent before this date or message ID.")]
+        public Snowflake? Before { get; init; }
+
+        [CommandOption("partition", 'p', Description = "Split output into partitions, each limited to this number of messages (e.g. '100') or file size (e.g. '10mb').")]
+        public PartitionLimit PartitionLimit { get; init; } = PartitionLimit.Null;
+
+        [CommandOption("filter", Description = "Only include messages that satisfy this filter (e.g. 'from:foo#1234' or 'has:image').")]
+        public MessageFilter MessageFilter { get; init; } = MessageFilter.Null;
+
+        [CommandOption("parallel", Description = "Limits how many channels can be exported in parallel.")]
+        public int ParallelLimit { get; init; } = 1;
+
+        [CommandOption("media", Description = "Download referenced media content.")]
+        public bool ShouldDownloadMedia { get; init; }
+
+        [CommandOption("reuse-media", Description = "Reuse already existing media content to skip redundant downloads.")]
+        public bool ShouldReuseMedia { get; init; }
+
+        [CommandOption("dateformat", Description = "Format used when writing dates.")]
+        public string DateFormat { get; init; } = "dd-MMM-yy hh:mm tt";
+
+        private ChannelExporter? _channelExporter;
+        protected ChannelExporter Exporter => _channelExporter ??= new ChannelExporter(Discord);
+
+        protected async ValueTask ExportAsync(IConsole console, IReadOnlyList<Channel> channels)
+        {
+            await console.Output.WriteLineAsync($"Exporting {channels.Count} channel(s)...");
+
+            var errors = new ConcurrentDictionary<Channel, string>();
+
+            // Wrap everything in a progress ticker
+            await console.CreateProgressTicker().StartAsync(async progressContext =>
+            {
+                await channels.ParallelForEachAsync(async channel =>
+                {
+                    // Export
+                    try
+                    {
+                        await progressContext.StartTaskAsync($"{channel.Category} / {channel.Name}", async progress =>
+                        {
+                            var guild = await Discord.GetGuildAsync(channel.GuildId);
+
+                            var request = new ExportRequest(
+                                guild,
+                                channel,
+                                OutputPath,
+                                ExportFormat,
+                                After,
+                                Before,
+                                PartitionLimit,
+                                MessageFilter,
+                                ShouldDownloadMedia,
+                                ShouldReuseMedia,
+                                DateFormat
+                            );
+
+                            await Exporter.ExportChannelAsync(request, progress);
+                        });
+                    }
+                    catch (DiscordChatExporterException ex) when (!ex.IsCritical)
+                    {
+                        errors[channel] = ex.Message;
+                    }
+                }, ParallelLimit.ClampMin(1));
+            });
+
+            // Print result
+            using (console.WithForegroundColor(ConsoleColor.White))
+            {
+                await console.Output.WriteLineAsync(
+                    $"Successfully exported {channels.Count - errors.Count} channel(s)."
+                );
+            }
+
+            // Print errors
+            if (errors.Any())
+            {
+                await console.Output.WriteLineAsync();
+
+                using (console.WithForegroundColor(ConsoleColor.Red))
+                {
+                    await console.Output.WriteLineAsync(
+                        $"Failed to export {errors.Count} channel(s):"
+                    );
+                }
+
+                foreach (var (channel, error) in errors)
+                {
+                    await console.Output.WriteAsync($"{channel.Category} / {channel.Name}: ");
+
+                    using (console.WithForegroundColor(ConsoleColor.Red))
+                        await console.Output.WriteLineAsync(error);
+                }
+
+                await console.Output.WriteLineAsync();
+            }
+
+            // Fail the command if ALL channels failed to export.
+            // Having some of the channels fail to export is fine and expected.
+            if (errors.Count >= channels.Count)
+            {
+                throw new CommandException("Export failed.");
+            }
+        }
+
+        public override ValueTask ExecuteAsync(IConsole console)
+        {
+            if (ShouldReuseMedia && !ShouldDownloadMedia)
+            {
+                throw new CommandException("Option --reuse-media cannot be used without --media.");
+            }
+
+            return default;
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/Base/TokenCommandBase.cs

@@ -0,0 +1,29 @@
+using System.Threading.Tasks;
+using CliFx;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Core.Discord;
+
+namespace DiscordChatExporter.Cli.Commands.Base
+{
+    public abstract class TokenCommandBase : ICommand
+    {
+        [CommandOption("token", 't', IsRequired = true, EnvironmentVariable = "DISCORD_TOKEN", Description = "Authentication token.")]
+        public string TokenValue { get; init; } = "";
+
+        [CommandOption("bot", 'b', EnvironmentVariable = "DISCORD_TOKEN_BOT", Description = "Authenticate as a bot.")]
+        public bool IsBotToken { get; init; }
+
+        private AuthToken GetAuthToken() => new(
+            IsBotToken
+                ? AuthTokenType.Bot
+                : AuthTokenType.User,
+            TokenValue
+        );
+
+        private DiscordClient? _discordClient;
+        protected DiscordClient Discord => _discordClient ??= new DiscordClient(GetAuthToken());
+
+        public abstract ValueTask ExecuteAsync(IConsole console);
+    }
+}

DiscordChatExporter.Cli/Commands/ExportAllCommand.cs

@@ -0,0 +1,46 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("exportall", Description = "Export all accessible channels.")]
+    public class ExportAllCommand : ExportCommandBase
+    {
+        [CommandOption("include-dm", Description = "Include direct message channels.")]
+        public bool IncludeDirectMessages { get; init; } = true;
+
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            await base.ExecuteAsync(console);
+
+            // Get channel metadata
+            await console.Output.WriteLineAsync("Fetching channels...");
+
+            var channels = new List<Channel>();
+
+            // Aggregate channels from all guilds
+            await foreach (var guild in Discord.GetUserGuildsAsync())
+            {
+                // Skip DMs if instructed to
+                if (!IncludeDirectMessages && guild.Id == Guild.DirectMessages.Id)
+                    continue;
+
+                await foreach (var channel in Discord.GetGuildChannelsAsync(guild.Id))
+                {
+                    // Skip non-text channels
+                    if (!channel.IsTextChannel)
+                        continue;
+
+                    channels.Add(channel);
+                }
+            }
+
+            // Export
+            await ExportAsync(console, channels);
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/ExportChannelsCommand.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("export", Description = "Export one or multiple channels.")]
+    public class ExportChannelsCommand : ExportCommandBase
+    {
+        // TODO: change this to plural (breaking change)
+        [CommandOption("channel", 'c', IsRequired = true, Description = "Channel ID(s).")]
+        public IReadOnlyList<Snowflake> ChannelIds { get; init; } = Array.Empty<Snowflake>();
+
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            await base.ExecuteAsync(console);
+
+            // Get channel metadata
+            await console.Output.WriteLineAsync("Fetching channel(s)...");
+
+            var channels = new List<Channel>();
+
+            foreach (var channelId in ChannelIds)
+            {
+                var channel = await Discord.GetChannelAsync(channelId);
+                channels.Add(channel);
+            }
+
+            // Export
+            await ExportAsync(console, channels);
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/ExportDirectMessagesCommand.cs

@@ -0,0 +1,27 @@
+using System.Linq;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("exportdm", Description = "Export all direct message channels.")]
+    public class ExportDirectMessagesCommand : ExportCommandBase
+    {
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            await base.ExecuteAsync(console);
+
+            // Get channel metadata
+            await console.Output.WriteLineAsync("Fetching channels...");
+            var channels = await Discord.GetGuildChannelsAsync(Guild.DirectMessages.Id);
+            var textChannels = channels.Where(c => c.IsTextChannel).ToArray();
+
+            // Export
+            await ExportAsync(console, textChannels);
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/ExportGuildCommand.cs

@@ -0,0 +1,30 @@
+using System.Linq;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("exportguild", Description = "Export all channels within specified guild.")]
+    public class ExportGuildCommand : ExportCommandBase
+    {
+        [CommandOption("guild", 'g', IsRequired = true, Description = "Guild ID.")]
+        public Snowflake GuildId { get; init; }
+
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            await base.ExecuteAsync(console);
+
+            // Get channel metadata
+            await console.Output.WriteLineAsync("Fetching channels...");
+            var channels = await Discord.GetGuildChannelsAsync(GuildId);
+            var textChannels = channels.Where(c => c.IsTextChannel).ToArray();
+
+            // Export
+            await ExportAsync(console, textChannels);
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/GetChannelsCommand.cs

@@ -0,0 +1,45 @@
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("channels", Description = "Get the list of channels in a guild.")]
+    public class GetChannelsCommand : TokenCommandBase
+    {
+        [CommandOption("guild", 'g', IsRequired = true, Description = "Guild ID.")]
+        public Snowflake GuildId { get; init; }
+
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            var channels = await Discord.GetGuildChannelsAsync(GuildId);
+
+            var textChannels = channels
+                .Where(c => c.IsTextChannel)
+                .OrderBy(c => c.Category.Position)
+                .ThenBy(c => c.Name)
+                .ToArray();
+
+            foreach (var channel in textChannels)
+            {
+                // Channel ID
+                await console.Output.WriteAsync(channel.Id.ToString());
+
+                // Separator
+                using (console.WithForegroundColor(ConsoleColor.DarkGray))
+                    await console.Output.WriteAsync(" | ");
+
+                // Channel category / name
+                using (console.WithForegroundColor(ConsoleColor.White))
+                    await console.Output.WriteAsync($"{channel.Category} / {channel.Name}");
+
+                await console.Output.WriteLineAsync();
+            }
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/GetDirectMessageChannelsCommand.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("dm", Description = "Get the list of direct message channels.")]
+    public class GetDirectMessageChannelsCommand : TokenCommandBase
+    {
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            var channels = await Discord.GetGuildChannelsAsync(Guild.DirectMessages.Id);
+
+            var textChannels = channels
+                .Where(c => c.IsTextChannel)
+                .OrderBy(c => c.Category.Position)
+                .ThenBy(c => c.Name)
+                .ToArray();
+
+            foreach (var channel in textChannels)
+            {
+                // Channel ID
+                await console.Output.WriteAsync(channel.Id.ToString());
+
+                // Separator
+                using (console.WithForegroundColor(ConsoleColor.DarkGray))
+                    await console.Output.WriteAsync(" | ");
+
+                // Channel category / name
+                using (console.WithForegroundColor(ConsoleColor.White))
+                    await console.Output.WriteAsync($"{channel.Category} / {channel.Name}");
+
+                await console.Output.WriteLineAsync();
+            }
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/GetGuildsCommand.cs

@@ -0,0 +1,35 @@
+using System;
+using System.Linq;
+using System.Threading.Tasks;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+using DiscordChatExporter.Cli.Commands.Base;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("guilds", Description = "Get the list of accessible guilds.")]
+    public class GetGuildsCommand : TokenCommandBase
+    {
+        public override async ValueTask ExecuteAsync(IConsole console)
+        {
+            var guilds = await Discord.GetUserGuildsAsync();
+
+            foreach (var guild in guilds.OrderBy(g => g.Name))
+            {
+                // Guild ID
+                await console.Output.WriteAsync(guild.Id.ToString());
+
+                // Separator
+                using (console.WithForegroundColor(ConsoleColor.DarkGray))
+                    await console.Output.WriteAsync(" | ");
+
+                // Guild name
+                using (console.WithForegroundColor(ConsoleColor.White))
+                    await console.Output.WriteAsync(guild.Name);
+
+                await console.Output.WriteLineAsync();
+            }
+        }
+    }
+}

DiscordChatExporter.Cli/Commands/GuideCommand.cs

@@ -0,0 +1,67 @@
+using System;
+using System.Threading.Tasks;
+using CliFx;
+using CliFx.Attributes;
+using CliFx.Infrastructure;
+
+namespace DiscordChatExporter.Cli.Commands
+{
+    [Command("guide", Description = "Explains how to obtain token, guild or channel ID.")]
+    public class GuideCommand : ICommand
+    {
+        public ValueTask ExecuteAsync(IConsole console)
+        {
+            using (console.WithForegroundColor(ConsoleColor.White))
+                console.Output.WriteLine("To get user token:");
+
+            console.Output.WriteLine(" 1. Open Discord");
+            console.Output.WriteLine(" 2. Press Ctrl+Shift+I to show developer tools");
+            console.Output.WriteLine(" 3. Press Ctrl+Shift+M to toggle device toolbar");
+            console.Output.WriteLine(" 4. Navigate to the Application tab");
+            console.Output.WriteLine(" 5. On the left, expand Local Storage and select https://discord.com");
+            console.Output.WriteLine(" 6. Type \"token\" into the Filter box");
+            console.Output.WriteLine(" 7. If the token key does not appear, press Ctrl+R to reload");
+            console.Output.WriteLine(" 8. Copy the value of the token key");
+            console.Output.WriteLine(" *  Automating user accounts is technically against TOS, use at your own risk.");
+            console.Output.WriteLine();
+
+            using (console.WithForegroundColor(ConsoleColor.White))
+                console.Output.WriteLine("To get bot token:");
+
+            console.Output.WriteLine(" 1. Go to Discord developer portal");
+            console.Output.WriteLine(" 2. Open your application's settings");
+            console.Output.WriteLine(" 3. Navigate to the Bot section on the left");
+            console.Output.WriteLine(" 4. Under Token click Copy");
+            console.Output.WriteLine();
+
+            using (console.WithForegroundColor(ConsoleColor.White))
+                console.Output.WriteLine("To get guild ID or guild channel ID:");
+
+            console.Output.WriteLine(" 1. Open Discord");
+            console.Output.WriteLine(" 2. Open Settings");
+            console.Output.WriteLine(" 3. Go to Appearance section");
+            console.Output.WriteLine(" 4. Enable Developer Mode");
+            console.Output.WriteLine(" 5. Right click on the desired guild or channel and click Copy ID");
+            console.Output.WriteLine();
+
+            using (console.WithForegroundColor(ConsoleColor.White))
+                console.Output.WriteLine("To get direct message channel ID:");
+
+            console.Output.WriteLine(" 1. Open Discord");
+            console.Output.WriteLine(" 2. Open the desired direct message channel");
+            console.Output.WriteLine(" 3. Press Ctrl+Shift+I to show developer tools");
+            console.Output.WriteLine(" 4. Navigate to the Console tab");
+            console.Output.WriteLine(" 5. Type \"window.location.href\" and press Enter");
+            console.Output.WriteLine(" 6. Copy the first long sequence of numbers inside the URL");
+            console.Output.WriteLine();
+
+            using (console.WithForegroundColor(ConsoleColor.White))
+                console.Output.WriteLine("For more information, check out the wiki:");
+
+            using (console.WithForegroundColor(ConsoleColor.DarkCyan))
+                console.Output.WriteLine("https://github.com/Tyrrrz/DiscordChatExporter/wiki");
+
+            return default;
+        }
+    }
+}

DiscordChatExporter.Cli/Container.cs

@@ -1,24 +0,0 @@
-using DiscordChatExporter.Core.Services;
-using StyletIoC;
-
-namespace DiscordChatExporter.Cli
-{
-    public static class Container
-    {
-        public static IContainer Instance { get; }
-
-        static Container()
-        {
-            var builder = new StyletIoCBuilder();
-
-            // Autobind services in the .Core assembly
-            builder.Autobind(typeof(DataService).Assembly);
-
-            // Bind settings as singleton
-            builder.Bind<SettingsService>().ToSelf().InSingletonScope();
-
-            // Set instance
-            Instance = builder.BuildContainer();
-        }
-    }
-}

DiscordChatExporter.Cli/DiscordChatExporter.Cli.csproj

@@ -1,22 +1,19 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
-        <OutputType>Exe</OutputType>
-        <TargetFramework>net461</TargetFramework>
-        <Version>2.10.1</Version>
-        <Company>Tyrrrz</Company>
-        <Copyright>Copyright (c) Alexey Golub</Copyright>
-        <ApplicationIcon>..\favicon.ico</ApplicationIcon>
-    </PropertyGroup>
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <ApplicationIcon>..\favicon.ico</ApplicationIcon>
+  </PropertyGroup>
 
-    <ItemGroup>
-        <PackageReference Include="CommandLineParser" Version="2.3.0" />
-        <PackageReference Include="Stylet" Version="1.1.22" />
-        <PackageReference Include="Tyrrrz.Extensions" Version="1.5.1" />
-    </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="CliFx" Version="2.0.6" />
+    <PackageReference Include="Spectre.Console" Version="0.41.0" />
+    <PackageReference Include="Gress" Version="1.2.0" />
+    <PackageReference Include="Tyrrrz.Extensions" Version="1.6.5" />
+  </ItemGroup>
 
-    <ItemGroup>
-        <ProjectReference Include="..\DiscordChatExporter.Core\DiscordChatExporter.Core.csproj" />
-    </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\DiscordChatExporter.Core\DiscordChatExporter.Core.csproj" />
+  </ItemGroup>
 
 </Project>

DiscordChatExporter.Cli/Internal/InlineProgress.cs

@@ -1,28 +0,0 @@
-using System;
-
-namespace DiscordChatExporter.Cli.Internal
-{
-    internal class InlineProgress : IProgress<double>, IDisposable
-    {
-        private readonly int _posX;
-        private readonly int _posY;
-
-        public InlineProgress()
-        {
-            _posX = Console.CursorLeft;
-            _posY = Console.CursorTop;
-        }
-
-        public void Report(double progress)
-        {
-            Console.SetCursorPosition(_posX, _posY);
-            Console.WriteLine($"{progress:P1}");
-        }
-
-        public void Dispose()
-        {
-            Console.SetCursorPosition(_posX, _posY);
-            Console.WriteLine("Completed ✓");
-        }
-    }
-}

DiscordChatExporter.Cli/Program.cs

@@ -1,72 +1,14 @@
-using System;
-using System.Linq;
-using CommandLine;
-using DiscordChatExporter.Cli.Verbs;
-using DiscordChatExporter.Cli.Verbs.Options;
+using System.Threading.Tasks;
+using CliFx;
 
 namespace DiscordChatExporter.Cli
 {
     public static class Program
     {
-        private static void PrintTokenHelp()
-        {
-            Console.WriteLine("# To get user token:");
-            Console.WriteLine(" 1. Open Discord");
-            Console.WriteLine(" 2. Press Ctrl+Shift+I to show developer tools");
-            Console.WriteLine(" 3. Press Ctrl+R to reload");
-            Console.WriteLine(" 4. Navigate to the Application tab");
-            Console.WriteLine(" 5. Select \"Local Storage\" > \"https://discordapp.com\" on the left");
-            Console.WriteLine(" 6. Find \"token\" under key and copy the value");
-            Console.WriteLine();
-            Console.WriteLine("# To get bot token:");
-            Console.WriteLine(" 1. Go to Discord developer portal");
-            Console.WriteLine(" 2. Open your application's settings");
-            Console.WriteLine(" 3. Navigate to the Bot section on the left");
-            Console.WriteLine(" 4. Under Token click Copy");
-            Console.WriteLine();
-            Console.WriteLine("# To get guild or channel ID:");
-            Console.WriteLine(" 1. Open Discord");
-            Console.WriteLine(" 2. Open Settings");
-            Console.WriteLine(" 3. Go to Appearance section");
-            Console.WriteLine(" 4. Enable Developer Mode");
-            Console.WriteLine(" 5. Right click on the desired guild or channel and click Copy ID");
-        }
-
-        public static void Main(string[] args)
-        {
-            // Get all verb types
-            var verbTypes = new[]
-            {
-                typeof(ExportChannelOptions),
-                typeof(ExportDirectMessagesOptions),
-                typeof(ExportGuildOptions),
-                typeof(GetChannelsOptions),
-                typeof(GetDirectMessageChannelsOptions),
-                typeof(GetGuildsOptions)
-            };
-
-            // Parse command line arguments
-            var parsedArgs = Parser.Default.ParseArguments(args, verbTypes);
-
-            // Execute commands
-            parsedArgs.WithParsed<ExportChannelOptions>(o => new ExportChannelVerb(o).Execute());
-            parsedArgs.WithParsed<ExportDirectMessagesOptions>(o => new ExportDirectMessagesVerb(o).Execute());
-            parsedArgs.WithParsed<ExportGuildOptions>(o => new ExportGuildVerb(o).Execute());
-            parsedArgs.WithParsed<GetChannelsOptions>(o => new GetChannelsVerb(o).Execute());
-            parsedArgs.WithParsed<GetDirectMessageChannelsOptions>(o => new GetDirectMessageChannelsVerb(o).Execute());
-            parsedArgs.WithParsed<GetGuildsOptions>(o => new GetGuildsVerb(o).Execute());
-
-            // Show token help if help requested or no verb specified
-            parsedArgs.WithNotParsed(errs =>
-            {
-                var err = errs.First();
-
-                if (err.Tag == ErrorType.NoVerbSelectedError)
-                    PrintTokenHelp();
-
-                if (err.Tag == ErrorType.HelpVerbRequestedError && args.Length == 1)
-                    PrintTokenHelp();
-            });
-        }
+        public static async Task<int> Main(string[] args) =>
+            await new CliApplicationBuilder()
+                .AddCommandsFromThisAssembly()
+                .Build()
+                .RunAsync(args);
     }
 }

DiscordChatExporter.Cli/Utils/Extensions/ConsoleExtensions.cs

@@ -0,0 +1,52 @@
+using System;
+using System.Threading.Tasks;
+using CliFx.Infrastructure;
+using Spectre.Console;
+
+namespace DiscordChatExporter.Cli.Utils.Extensions
+{
+    internal static class ConsoleExtensions
+    {
+        public static IAnsiConsole CreateAnsiConsole(this IConsole console) => AnsiConsole.Create(
+            new AnsiConsoleSettings
+            {
+                Ansi = AnsiSupport.Detect,
+                ColorSystem = ColorSystemSupport.Detect,
+                Out = new AnsiConsoleOutput(console.Output)
+            }
+        );
+
+        public static Progress CreateProgressTicker(this IConsole console) => console
+            .CreateAnsiConsole()
+            .Progress()
+            .AutoClear(false)
+            .AutoRefresh(true)
+            .HideCompleted(false)
+            .Columns(
+                new TaskDescriptionColumn {Alignment = Justify.Left},
+                new ProgressBarColumn(),
+                new PercentageColumn()
+            );
+
+        public static async ValueTask StartTaskAsync(
+            this ProgressContext progressContext,
+            string description,
+            Func<ProgressTask, ValueTask> performOperationAsync)
+        {
+            var progressTask = progressContext.AddTask(
+                // Don't recognize random square brackets as style tags
+                Markup.Escape(description),
+                new ProgressTaskSettings {MaxValue = 1}
+            );
+
+            try
+            {
+                await performOperationAsync(progressTask);
+            }
+            finally
+            {
+                progressTask.StopTask();
+            }
+        }
+    }
+}

DiscordChatExporter.Cli/Utils/Pollyfills.cs

@@ -0,0 +1,9 @@
+// ReSharper disable CheckNamespace
+// TODO: remove after moving to .NET 5
+
+namespace System.Runtime.CompilerServices
+{
+    internal static class IsExternalInit
+    {
+    }
+}

DiscordChatExporter.Cli/Verbs/ExportChannelVerb.cs

@@ -1,57 +0,0 @@
-using System;
-using System.IO;
-using System.Threading.Tasks;
-using DiscordChatExporter.Cli.Internal;
-using DiscordChatExporter.Cli.Verbs.Options;
-using DiscordChatExporter.Core.Helpers;
-using DiscordChatExporter.Core.Services;
-using Tyrrrz.Extensions;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public class ExportChannelVerb : Verb<ExportChannelOptions>
-    {
-        public ExportChannelVerb(ExportChannelOptions options)
-            : base(options)
-        {
-        }
-
-        public override async Task ExecuteAsync()
-        {
-            // Get services
-            var settingsService = Container.Instance.Get<SettingsService>();
-            var dataService = Container.Instance.Get<DataService>();
-            var exportService = Container.Instance.Get<ExportService>();
-
-            // Configure settings
-            if (Options.DateFormat.IsNotBlank())
-                settingsService.DateFormat = Options.DateFormat;
-            if (Options.MessageGroupLimit > 0)
-                settingsService.MessageGroupLimit = Options.MessageGroupLimit;
-
-            // Track progress
-            Console.Write($"Exporting channel [{Options.ChannelId}]... ");
-            using (var progress = new InlineProgress())
-            {
-                // Get chat log
-                var chatLog = await dataService.GetChatLogAsync(Options.GetToken(), Options.ChannelId,
-                    Options.After, Options.Before, progress);
-
-                // Generate file path if not set or is a directory
-                var filePath = Options.OutputPath;
-                if (filePath.IsBlank() || ExportHelper.IsDirectoryPath(filePath))
-                {
-                    // Generate default file name
-                    var fileName = ExportHelper.GetDefaultExportFileName(Options.ExportFormat, chatLog.Guild,
-                        chatLog.Channel, Options.After, Options.Before);
-
-                    // Combine paths
-                    filePath = Path.Combine(filePath ?? "", fileName);
-                }
-
-                // Export
-                exportService.ExportChatLog(chatLog, filePath, Options.ExportFormat, Options.PartitionLimit);
-            }
-        }
-    }
-}

DiscordChatExporter.Cli/Verbs/ExportDirectMessagesVerb.cs

@@ -1,76 +0,0 @@
-using System;
-using System.IO;
-using System.Linq;
-using System.Net;
-using System.Threading.Tasks;
-using DiscordChatExporter.Cli.Internal;
-using DiscordChatExporter.Cli.Verbs.Options;
-using DiscordChatExporter.Core.Exceptions;
-using DiscordChatExporter.Core.Helpers;
-using DiscordChatExporter.Core.Services;
-using Tyrrrz.Extensions;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public class ExportDirectMessagesVerb : Verb<ExportDirectMessagesOptions>
-    {
-        public ExportDirectMessagesVerb(ExportDirectMessagesOptions options)
-            : base(options)
-        {
-        }
-
-        public override async Task ExecuteAsync()
-        {
-            // Get services
-            var settingsService = Container.Instance.Get<SettingsService>();
-            var dataService = Container.Instance.Get<DataService>();
-            var exportService = Container.Instance.Get<ExportService>();
-
-            // Configure settings
-            if (Options.DateFormat.IsNotBlank())
-                settingsService.DateFormat = Options.DateFormat;
-            if (Options.MessageGroupLimit > 0)
-                settingsService.MessageGroupLimit = Options.MessageGroupLimit;
-
-            // Get channels
-            var channels = await dataService.GetDirectMessageChannelsAsync(Options.GetToken());
-
-            // Order channels
-            channels = channels.OrderBy(c => c.Name).ToArray();
-
-            // Loop through channels
-            foreach (var channel in channels)
-            {
-                try
-                {
-                    // Track progress
-                    Console.Write($"Exporting channel [{channel.Name}]... ");
-                    using (var progress = new InlineProgress())
-                    {
-                        // Get chat log
-                        var chatLog = await dataService.GetChatLogAsync(Options.GetToken(), channel,
-                            Options.After, Options.Before, progress);
-
-                        // Generate default file name
-                        var fileName = ExportHelper.GetDefaultExportFileName(Options.ExportFormat, chatLog.Guild,
-                            chatLog.Channel, Options.After, Options.Before);
-
-                        // Generate file path
-                        var filePath = Path.Combine(Options.OutputPath ?? "", fileName);
-
-                        // Export
-                        exportService.ExportChatLog(chatLog, filePath, Options.ExportFormat, Options.PartitionLimit);
-                    }
-                }
-                catch (HttpErrorStatusCodeException ex) when (ex.StatusCode == HttpStatusCode.Forbidden)
-                {
-                    Console.Error.WriteLine("You don't have access to this channel");
-                }
-                catch (HttpErrorStatusCodeException ex) when (ex.StatusCode == HttpStatusCode.NotFound)
-                {
-                    Console.Error.WriteLine("This channel doesn't exist");
-                }
-            }
-        }
-    }
-}

DiscordChatExporter.Cli/Verbs/ExportGuildVerb.cs

@@ -1,77 +0,0 @@
-using System;
-using System.IO;
-using System.Linq;
-using System.Net;
-using System.Threading.Tasks;
-using DiscordChatExporter.Cli.Internal;
-using DiscordChatExporter.Cli.Verbs.Options;
-using DiscordChatExporter.Core.Exceptions;
-using DiscordChatExporter.Core.Helpers;
-using DiscordChatExporter.Core.Models;
-using DiscordChatExporter.Core.Services;
-using Tyrrrz.Extensions;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public class ExportGuildVerb : Verb<ExportGuildOptions>
-    {
-        public ExportGuildVerb(ExportGuildOptions options)
-            : base(options)
-        {
-        }
-
-        public override async Task ExecuteAsync()
-        {
-            // Get services
-            var settingsService = Container.Instance.Get<SettingsService>();
-            var dataService = Container.Instance.Get<DataService>();
-            var exportService = Container.Instance.Get<ExportService>();
-
-            // Configure settings
-            if (Options.DateFormat.IsNotBlank())
-                settingsService.DateFormat = Options.DateFormat;
-            if (Options.MessageGroupLimit > 0)
-                settingsService.MessageGroupLimit = Options.MessageGroupLimit;
-
-            // Get channels
-            var channels = await dataService.GetGuildChannelsAsync(Options.GetToken(), Options.GuildId);
-
-            // Filter and order channels
-            channels = channels.Where(c => c.Type == ChannelType.GuildTextChat).OrderBy(c => c.Name).ToArray();
-
-            // Loop through channels
-            foreach (var channel in channels)
-            {
-                try
-                {
-                    // Track progress
-                    Console.Write($"Exporting channel [{channel.Name}]... ");
-                    using (var progress = new InlineProgress())
-                    {
-                        // Get chat log
-                        var chatLog = await dataService.GetChatLogAsync(Options.GetToken(), channel,
-                            Options.After, Options.Before, progress);
-
-                        // Generate default file name
-                        var fileName = ExportHelper.GetDefaultExportFileName(Options.ExportFormat, chatLog.Guild,
-                            chatLog.Channel, Options.After, Options.Before);
-
-                        // Generate file path
-                        var filePath = Path.Combine(Options.OutputPath ?? "", fileName);
-
-                        // Export
-                        exportService.ExportChatLog(chatLog, filePath, Options.ExportFormat, Options.PartitionLimit);
-                    }
-                }
-                catch (HttpErrorStatusCodeException ex) when (ex.StatusCode == HttpStatusCode.Forbidden)
-                {
-                    Console.Error.WriteLine("You don't have access to this channel");
-                }
-                catch (HttpErrorStatusCodeException ex) when (ex.StatusCode == HttpStatusCode.NotFound)
-                {
-                    Console.Error.WriteLine("This channel doesn't exist");
-                }
-            }
-        }
-    }
-}

DiscordChatExporter.Cli/Verbs/GetChannelsVerb.cs

@@ -1,33 +0,0 @@
-using System;
-using System.Linq;
-using System.Threading.Tasks;
-using DiscordChatExporter.Cli.Verbs.Options;
-using DiscordChatExporter.Core.Models;
-using DiscordChatExporter.Core.Services;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public class GetChannelsVerb : Verb<GetChannelsOptions>
-    {
-        public GetChannelsVerb(GetChannelsOptions options)
-            : base(options)
-        {
-        }
-
-        public override async Task ExecuteAsync()
-        {
-            // Get data service
-            var dataService = Container.Instance.Get<DataService>();
-
-            // Get channels
-            var channels = await dataService.GetGuildChannelsAsync(Options.GetToken(), Options.GuildId);
-
-            // Filter and order channels
-            channels = channels.Where(c => c.Type == ChannelType.GuildTextChat).OrderBy(c => c.Name).ToArray();
-
-            // Print result
-            foreach (var channel in channels)
-                Console.WriteLine($"{channel.Id} | {channel.Name}");
-        }
-    }
-}

DiscordChatExporter.Cli/Verbs/GetDirectMessageChannelsVerb.cs

@@ -1,32 +0,0 @@
-using System;
-using System.Linq;
-using System.Threading.Tasks;
-using DiscordChatExporter.Cli.Verbs.Options;
-using DiscordChatExporter.Core.Services;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public class GetDirectMessageChannelsVerb : Verb<GetDirectMessageChannelsOptions>
-    {
-        public GetDirectMessageChannelsVerb(GetDirectMessageChannelsOptions options) 
-            : base(options)
-        {
-        }
-
-        public override async Task ExecuteAsync()
-        {
-            // Get data service
-            var dataService = Container.Instance.Get<DataService>();
-
-            // Get channels
-            var channels = await dataService.GetDirectMessageChannelsAsync(Options.GetToken());
-
-            // Order channels
-            channels = channels.OrderBy(c => c.Name).ToArray();
-
-            // Print result
-            foreach (var channel in channels)
-                Console.WriteLine($"{channel.Id} | {channel.Name}");
-        }
-    }
-}

DiscordChatExporter.Cli/Verbs/GetGuildsVerb.cs

@@ -1,32 +0,0 @@
-using System;
-using System.Linq;
-using System.Threading.Tasks;
-using DiscordChatExporter.Cli.Verbs.Options;
-using DiscordChatExporter.Core.Services;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public class GetGuildsVerb : Verb<GetGuildsOptions>
-    {
-        public GetGuildsVerb(GetGuildsOptions options) 
-            : base(options)
-        {
-        }
-
-        public override async Task ExecuteAsync()
-        {
-            // Get data service
-            var dataService = Container.Instance.Get<DataService>();
-
-            // Get guilds
-            var guilds = await dataService.GetUserGuildsAsync(Options.GetToken());
-
-            // Order guilds
-            guilds = guilds.OrderBy(g => g.Name).ToArray();
-
-            // Print result
-            foreach (var guild in guilds)
-                Console.WriteLine($"{guild.Id} | {guild.Name}");
-        }
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/ExportChannelOptions.cs

@@ -1,11 +0,0 @@
-using CommandLine;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    [Verb("export", HelpText = "Export channel.")]
-    public class ExportChannelOptions : ExportOptions
-    {
-        [Option('c', "channel", Required = true, HelpText = "Channel ID.")]
-        public string ChannelId { get; set; }
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/ExportDirectMessagesOptions.cs

@@ -1,9 +0,0 @@
-using CommandLine;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    [Verb("exportdm", HelpText = "Export all direct message channels.")]
-    public class ExportDirectMessagesOptions : ExportOptions
-    {
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/ExportGuildOptions.cs

@@ -1,11 +0,0 @@
-using CommandLine;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    [Verb("exportguild", HelpText = "Export all channels within a given guild.")]
-    public class ExportGuildOptions : ExportOptions
-    {
-        [Option('g', "guild", Required = true, HelpText = "Guild ID.")]
-        public string GuildId { get; set; }
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/ExportOptions.cs

@@ -1,30 +0,0 @@
-using System;
-using CommandLine;
-using DiscordChatExporter.Core.Models;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    public abstract class ExportOptions : TokenOptions
-    {
-        [Option('f', "format", Default = ExportFormat.HtmlDark, HelpText = "Output file format.")]
-        public ExportFormat ExportFormat { get; set; }
-
-        [Option('o', "output", Default = null, HelpText = "Output file or directory path.")]
-        public string OutputPath { get; set; }
-
-        [Option("after", Default = null, HelpText = "Limit to messages sent after this date.")]
-        public DateTime? After { get; set; }
-
-        [Option("before", Default = null, HelpText = "Limit to messages sent before this date.")]
-        public DateTime? Before { get; set; }
-
-        [Option('p', "partition", Default = null, HelpText = "Split output into partitions limited to this number of messages.")]
-        public int? PartitionLimit { get; set; }
-
-        [Option("dateformat", Default = null, HelpText = "Date format used in output.")]
-        public string DateFormat { get; set; }
-
-        [Option("grouplimit", Default = 0, HelpText = "Message group limit.")]
-        public int MessageGroupLimit { get; set; }
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/GetChannelsOptions.cs

@@ -1,11 +0,0 @@
-using CommandLine;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    [Verb("channels", HelpText = "Get the list of channels in the given guild.")]
-    public class GetChannelsOptions : TokenOptions
-    {
-        [Option('g', "guild", Required = true, HelpText = "Guild ID.")]
-        public string GuildId { get; set; }
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/GetDirectMessageChannelsOptions.cs

@@ -1,9 +0,0 @@
-using CommandLine;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    [Verb("dm", HelpText = "Get the list of direct message channels.")]
-    public class GetDirectMessageChannelsOptions : TokenOptions
-    {
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/GetGuildsOptions.cs

@@ -1,9 +0,0 @@
-using CommandLine;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    [Verb("guilds", HelpText = "Get the list of accessible guilds.")]
-    public class GetGuildsOptions : TokenOptions
-    {
-    }
-}

DiscordChatExporter.Cli/Verbs/Options/TokenOptions.cs

@@ -1,16 +0,0 @@
-using CommandLine;
-using DiscordChatExporter.Core.Models;
-
-namespace DiscordChatExporter.Cli.Verbs.Options
-{
-    public abstract class TokenOptions
-    {
-        [Option('t', "token", Required = true, HelpText = "Authorization token.")]
-        public string TokenValue { get; set; }
-
-        [Option('b', "bot", Default = false, HelpText = "Whether this authorization token belongs to a bot.")]
-        public bool IsBotToken { get; set; }
-
-        public AuthToken GetToken() => new AuthToken(IsBotToken ? AuthTokenType.Bot : AuthTokenType.User, TokenValue);
-    }
-}

DiscordChatExporter.Cli/Verbs/Verb.cs

@@ -1,18 +0,0 @@
-using System.Threading.Tasks;
-
-namespace DiscordChatExporter.Cli.Verbs
-{
-    public abstract class Verb<TOptions>
-    {
-        protected TOptions Options { get; }
-
-        protected Verb(TOptions options)
-        {
-            Options = options;
-        }
-
-        public abstract Task ExecuteAsync();
-
-        public virtual void Execute() => ExecuteAsync().GetAwaiter().GetResult();
-    }
-}

DiscordChatExporter.Core.Markdown/DiscordChatExporter.Core.Markdown.csproj

@@ -1,12 +0,0 @@
-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <TargetFramework>net461</TargetFramework>
-  </PropertyGroup>
-
-  <ItemGroup>
-    <PackageReference Include="Sprache" Version="2.2.0" />
-    <PackageReference Include="Tyrrrz.Extensions" Version="1.5.1" />
-  </ItemGroup>
-
-</Project>

DiscordChatExporter.Core.Markdown/EmojiNode.cs

@@ -1,30 +0,0 @@
-using Tyrrrz.Extensions;
-
-namespace DiscordChatExporter.Core.Markdown
-{
-    public class EmojiNode : Node
-    {
-        public string Id { get; }
-
-        public string Name { get; }
-
-        public bool IsAnimated { get; }
-
-        public bool IsCustomEmoji => Id.IsNotBlank();
-
-        public EmojiNode(string lexeme, string id, string name, bool isAnimated)
-            : base(lexeme)
-        {
-            Id = id;
-            Name = name;
-            IsAnimated = isAnimated;
-        }
-
-        public EmojiNode(string lexeme, string name)
-            : this(lexeme, null, name, false)
-        {
-        }
-
-        public override string ToString() => $"<Emoji> {Name}";
-    }
-}

DiscordChatExporter.Core.Markdown/FormattedNode.cs

@@ -1,23 +0,0 @@
-using System.Collections.Generic;
-
-namespace DiscordChatExporter.Core.Markdown
-{
-    public class FormattedNode : Node
-    {
-        public string Token { get; }
-
-        public TextFormatting Formatting { get; }
-
-        public IReadOnlyList<Node> Children { get; }
-
-        public FormattedNode(string lexeme, string token, TextFormatting formatting, IReadOnlyList<Node> children)
-            : base(lexeme)
-        {
-            Token = token;
-            Formatting = formatting;
-            Children = children;
-        }
-
-        public override string ToString() => $"<{Formatting}> ({Children.Count} direct children)";
-    }
-}

DiscordChatExporter.Core.Markdown/Internal/Grammar.cs

@@ -1,178 +0,0 @@
-using System.Collections.Generic;
-using System.Linq;
-using System.Text.RegularExpressions;
-using Sprache;
-using Tyrrrz.Extensions;
-
-namespace DiscordChatExporter.Core.Markdown.Internal
-{
-    // The following parsing logic is meant to replicate Discord's markdown grammar as close as possible
-    internal static class Grammar
-    {
-        /* Formatting */
-
-        // Capture until the earliest double asterisk not followed by an asterisk
-        private static readonly Parser<Node> BoldFormattedNode =
-            Parse.RegexMatch(new Regex("\\*\\*(.+?)\\*\\*(?!\\*)", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "**", TextFormatting.Bold, BuildTree(m.Groups[1].Value)));
-
-        // Capture until the earliest single asterisk not preceded or followed by an asterisk
-        // Can't have whitespace right after opening or right before closing asterisk
-        private static readonly Parser<Node> ItalicFormattedNode =
-            Parse.RegexMatch(new Regex("\\*(?!\\s)(.+?)(?<!\\s|\\*)\\*(?!\\*)", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "*", TextFormatting.Italic, BuildTree(m.Groups[1].Value)));
-
-        // Can't have underscores inside
-        // Can't have word characters right after closing underscore
-        private static readonly Parser<Node> ItalicAltFormattedNode =
-            Parse.RegexMatch(new Regex("_([^_]+?)_(?!\\w)", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "_", TextFormatting.Italic, BuildTree(m.Groups[1].Value)));
-
-        // Treated as a separate entity for simplicity
-        // Capture until the earliest triple asterisk not preceded or followed by an asterisk
-        private static readonly Parser<Node> ItalicBoldFormattedNode =
-            Parse.RegexMatch(new Regex("\\*(\\*\\*(?:.+?)\\*\\*)\\*(?!\\*)", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "*", TextFormatting.Italic, BuildTree(m.Groups[1].Value)));
-
-        // Capture until the earliest double underscore not followed by an underscore
-        private static readonly Parser<Node> UnderlineFormattedNode =
-            Parse.RegexMatch(new Regex("__(.+?)__(?!_)", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "__", TextFormatting.Underline, BuildTree(m.Groups[1].Value)));
-
-        // Treated as a separate entity for simplicity
-        // Capture until the earliest triple underscore not preceded or followed by an underscore
-        private static readonly Parser<Node> ItalicUnderlineFormattedNode =
-            Parse.RegexMatch(new Regex("_(__(?:.+?)__)_(?!_)", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "_", TextFormatting.Italic, BuildTree(m.Groups[1].Value)));
-
-        // Strikethrough is safe
-        private static readonly Parser<Node> StrikethroughFormattedNode =
-            Parse.RegexMatch(new Regex("~~(.+?)~~", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "~~", TextFormatting.Strikethrough, BuildTree(m.Groups[1].Value)));
-
-        // Spoiler is safe
-        private static readonly Parser<Node> SpoilerFormattedNode =
-            Parse.RegexMatch(new Regex("\\|\\|(.+?)\\|\\|", RegexOptions.Singleline))
-                .Select(m => new FormattedNode(m.Value, "||", TextFormatting.Spoiler, BuildTree(m.Groups[1].Value)));
-
-        // Combinator, order matters
-        private static readonly Parser<Node> AnyFormattedNode = 
-            ItalicBoldFormattedNode.Or(ItalicUnderlineFormattedNode)
-            .Or(BoldFormattedNode).Or(ItalicFormattedNode)
-            .Or(UnderlineFormattedNode).Or(ItalicAltFormattedNode)
-            .Or(StrikethroughFormattedNode).Or(SpoilerFormattedNode);
-
-        /* Code blocks */
-
-        // Can't have backticks inside and surrounding whitespace is trimmed
-        private static readonly Parser<Node> InlineCodeBlockNode =
-            Parse.RegexMatch(new Regex("`\\s*([^`]+?)\\s*`", RegexOptions.Singleline))
-                .Select(m => new InlineCodeBlockNode(m.Value, m.Groups[1].Value));
-
-        // The first word is a language identifier if it's the only word followed by a newline, the rest is code
-        private static readonly Parser<Node> MultilineCodeBlockNode =
-            Parse.RegexMatch(new Regex("```(?:(\\w*?)?(?:\\s*?\\n))?(.+?)```", RegexOptions.Singleline))
-                .Select(m => new MultilineCodeBlockNode(m.Value, m.Groups[1].Value, m.Groups[2].Value));
-
-        // Combinator, order matters
-        private static readonly Parser<Node> AnyCodeBlockNode = MultilineCodeBlockNode.Or(InlineCodeBlockNode);
-
-        /* Mentions */
-
-        // @everyone or @here
-        private static readonly Parser<Node> MetaMentionNode = Parse.RegexMatch("@(everyone|here)")
-            .Select(m => new MentionNode(m.Value, m.Groups[1].Value, MentionType.Meta));
-
-        // <@123456> or <@!123456>
-        private static readonly Parser<Node> UserMentionNode = Parse.RegexMatch("<@!?(\\d+)>")
-            .Select(m => new MentionNode(m.Value, m.Groups[1].Value, MentionType.User));
-
-        // <#123456>
-        private static readonly Parser<Node> ChannelMentionNode = Parse.RegexMatch("<#(\\d+)>")
-            .Select(m => new MentionNode(m.Value, m.Groups[1].Value, MentionType.Channel));
-
-        // <@&123456>
-        private static readonly Parser<Node> RoleMentionNode = Parse.RegexMatch("<@&(\\d+)>")
-            .Select(m => new MentionNode(m.Value, m.Groups[1].Value, MentionType.Role));
-
-        // Combinator, order matters
-        private static readonly Parser<Node> AnyMentionNode =
-            MetaMentionNode.Or(UserMentionNode).Or(ChannelMentionNode).Or(RoleMentionNode);
-
-        /* Emojis */
-
-        // Matches all standard unicode emojis
-        private static readonly Parser<Node> StandardEmojiNode = Parse.RegexMatch(
-                "([\\u2700-\\u27bf]|" +
-                "(?:\\ud83c[\\udde6-\\uddff]){2}|" +
-                "[\\ud800-\\udbff][\\udc00-\\udfff]|" +
-                "[\\u0023-\\u0039]\\u20e3|" +
-                "\\u3299|\\u3297|\\u303d|\\u3030|\\u24c2|\\ud83c[\\udd70-\\udd71]|\\ud83c[\\udd7e-\\udd7f]|\\ud83c\\udd8e|\\ud83c[\\udd91-\\udd9a]|\\ud83c[\\udde6-\\uddff]|" +
-                "\\ud83c[\\ude01-\\ude02]|\\ud83c\\ude1a|\\ud83c\\ude2f|\\ud83c[\\ude32-\\ude3a]|\\ud83c[\\ude50-\\ude51]|\\u203c|\\u2049|[\\u25aa-\\u25ab]|" +
-                "\\u25b6|\\u25c0|[\\u25fb-\\u25fe]|\\u00a9|\\u00ae|\\u2122|\\u2139|\\ud83c\\udc04|[\\u2600-\\u26FF]|\\u2b05|\\u2b06|\\u2b07|\\u2b1b|\\u2b1c|\\u2b50|" +
-                "\\u2b55|\\u231a|\\u231b|\\u2328|\\u23cf|[\\u23e9-\\u23f3]|[\\u23f8-\\u23fa]|\\ud83c\\udccf|\\u2934|\\u2935|[\\u2190-\\u21ff])")
-            .Select(m => new EmojiNode(m.Value, m.Groups[1].Value));
-
-        // <:lul:123456> or <a:lul:123456>
-        private static readonly Parser<Node> CustomEmojiNode = Parse.RegexMatch("<(a)?:(.+?):(\\d+)>")
-            .Select(m => new EmojiNode(m.Value, m.Groups[3].Value, m.Groups[2].Value, m.Groups[1].Value.IsNotBlank()));
-
-        // Combinator, order matters
-        private static readonly Parser<Node> AnyEmojiNode = StandardEmojiNode.Or(CustomEmojiNode);
-
-        /* Links */
-
-        // [title](link)
-        private static readonly Parser<Node> TitledLinkNode = Parse.RegexMatch("\\[(.+?)\\]\\((.+?)\\)")
-            .Select(m => new LinkNode(m.Value, m.Groups[2].Value, m.Groups[1].Value));
-
-        // Starts with http:// or https://, stops at the last non-whitespace character followed by whitespace or punctuation character
-        private static readonly Parser<Node> AutoLinkNode = Parse.RegexMatch("(https?://\\S*[^\\.,:;\"\'\\s])")
-            .Select(m => new LinkNode(m.Value, m.Groups[1].Value));
-
-        // Autolink surrounded by angular brackets
-        private static readonly Parser<Node> HiddenLinkNode = Parse.RegexMatch("<(https?://\\S*[^\\.,:;\"\'\\s])>")
-            .Select(m => new LinkNode(m.Value, m.Groups[1].Value));
-
-        // Combinator, order matters
-        private static readonly Parser<Node> AnyLinkNode = TitledLinkNode.Or(HiddenLinkNode).Or(AutoLinkNode); 
-
-        /* Text */
-
-        // Shrug is an exception and needs to be exempt from formatting
-        private static readonly Parser<Node> ShrugTextNode =
-            Parse.String("¯\\_(ツ)_/¯").Text().Select(s => new TextNode(s));
-
-        // Backslash escapes any following unicode surrogate pair
-        private static readonly Parser<Node> EscapedSurrogateTextNode =
-            from slash in Parse.Char('\\')
-            from high in Parse.AnyChar.Where(char.IsHighSurrogate)
-            from low in Parse.AnyChar
-            let lexeme = $"{slash}{high}{low}"
-            let text = $"{high}{low}"
-            select new TextNode(lexeme, text);
-
-        // Backslash escapes any following non-whitespace character except for digits and latin letters
-        private static readonly Parser<Node> EscapedTextNode =
-            Parse.RegexMatch("\\\\([^a-zA-Z0-9\\s])").Select(m => new TextNode(m.Value, m.Groups[1].Value));
-
-        // Combinator, order matters
-        private static readonly Parser<Node> AnyTextNode = ShrugTextNode.Or(EscapedSurrogateTextNode).Or(EscapedTextNode);
-
-        /* Aggregator and fallback */
-
-        // Any node recognized by above patterns
-        private static readonly Parser<Node> AnyRecognizedNode = AnyFormattedNode.Or(AnyCodeBlockNode)
-            .Or(AnyMentionNode).Or(AnyEmojiNode).Or(AnyLinkNode).Or(AnyTextNode);
-
-        // Any node not recognized by above patterns (treated as plain text)
-        private static readonly Parser<Node> FallbackNode =
-            Parse.AnyChar.Except(AnyRecognizedNode).AtLeastOnce().Text().Select(s => new TextNode(s));
-
-        // Any node
-        private static readonly Parser<Node> AnyNode = AnyRecognizedNode.Or(FallbackNode);
-
-        // Entry point
-        public static IReadOnlyList<Node> BuildTree(string input) => AnyNode.Many().Parse(input).ToArray();
-    }
-}

DiscordChatExporter.Core.Markdown/MarkdownParser.cs

@@ -1,10 +0,0 @@
-using System.Collections.Generic;
-using DiscordChatExporter.Core.Markdown.Internal;
-
-namespace DiscordChatExporter.Core.Markdown
-{
-    public static class MarkdownParser
-    {
-        public static IReadOnlyList<Node> Parse(string input) => Grammar.BuildTree(input);
-    }
-}

DiscordChatExporter.Core.Markdown/MentionNode.cs

@@ -1,18 +0,0 @@
-namespace DiscordChatExporter.Core.Markdown
-{
-    public class MentionNode : Node
-    {
-        public string Id { get; }
-
-        public MentionType Type { get; }
-
-        public MentionNode(string lexeme, string id, MentionType type)
-            : base(lexeme)
-        {
-            Id = id;
-            Type = type;
-        }
-
-        public override string ToString() => $"<{Type} mention> {Id}";
-    }
-}

DiscordChatExporter.Core.Markdown/MultilineCodeBlockNode.cs

@@ -1,18 +0,0 @@
-namespace DiscordChatExporter.Core.Markdown
-{
-    public class MultilineCodeBlockNode : Node
-    {
-        public string Language { get; }
-
-        public string Code { get; }
-
-        public MultilineCodeBlockNode(string lexeme, string language, string code)
-            : base(lexeme)
-        {
-            Language = language;
-            Code = code;
-        }
-
-        public override string ToString() => $"<Code [{Language}]> {Code}";
-    }
-}

DiscordChatExporter.Core.Markdown/Node.cs

@@ -1,12 +0,0 @@
-namespace DiscordChatExporter.Core.Markdown
-{
-    public abstract class Node
-    {
-        public string Lexeme { get; }
-
-        protected Node(string lexeme)
-        {
-            Lexeme = lexeme;
-        }
-    }
-}

DiscordChatExporter.Core/Discord/AuthToken.cs

@@ -0,0 +1,25 @@
+using System.Net.Http.Headers;
+
+namespace DiscordChatExporter.Core.Discord
+{
+    public class AuthToken
+    {
+        public AuthTokenType Type { get; }
+
+        public string Value { get; }
+
+        public AuthToken(AuthTokenType type, string value)
+        {
+            Type = type;
+            Value = value;
+        }
+
+        public AuthenticationHeaderValue GetAuthenticationHeader() => Type switch
+        {
+            AuthTokenType.Bot => new AuthenticationHeaderValue("Bot", Value),
+            _ => new AuthenticationHeaderValue(Value)
+        };
+
+        public override string ToString() => Value;
+    }
+}

DiscordChatExporter.Core/Discord/AuthTokenType.cs

@@ -1,4 +1,4 @@
-namespace DiscordChatExporter.Core.Models
+namespace DiscordChatExporter.Core.Discord
 {
     public enum AuthTokenType
     {

DiscordChatExporter.Core/Discord/Data/Attachment.cs

@@ -0,0 +1,78 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#attachment-object
+    public partial class Attachment : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public string Url { get; }
+
+        public string FileName { get; }
+
+        public string FileExtension => Path.GetExtension(FileName);
+
+        public int? Width { get; }
+
+        public int? Height { get; }
+
+        public bool IsImage => ImageFileExtensions.Contains(FileExtension);
+
+        public bool IsVideo => VideoFileExtensions.Contains(FileExtension);
+
+        public bool IsAudio => AudioFileExtensions.Contains(FileExtension);
+
+        public bool IsSpoiler => FileName.StartsWith("SPOILER_", StringComparison.Ordinal);
+
+        public FileSize FileSize { get; }
+
+        public Attachment(
+            Snowflake id,
+            string url,
+            string fileName,
+            int? width,
+            int? height,
+            FileSize fileSize)
+        {
+            Id = id;
+            Url = url;
+            FileName = fileName;
+            Width = width;
+            Height = height;
+            FileSize = fileSize;
+        }
+
+        public override string ToString() => FileName;
+    }
+
+    public partial class Attachment
+    {
+        private static readonly HashSet<string> ImageFileExtensions = new(StringComparer.OrdinalIgnoreCase)
+            {".jpg", ".jpeg", ".png", ".gif", ".bmp", ".webp"};
+
+        private static readonly HashSet<string> VideoFileExtensions = new(StringComparer.OrdinalIgnoreCase)
+            {".mp4", ".webm"};
+
+        private static readonly HashSet<string> AudioFileExtensions = new(StringComparer.OrdinalIgnoreCase)
+            {".mp3", ".wav", ".ogg", ".flac", ".m4a"};
+
+        public static Attachment Parse(JsonElement json)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+            var url = json.GetProperty("url").GetString();
+            var width = json.GetPropertyOrNull("width")?.GetInt32();
+            var height = json.GetPropertyOrNull("height")?.GetInt32();
+            var fileName = json.GetProperty("filename").GetString();
+            var fileSize = json.GetProperty("size").GetInt64().Pipe(FileSize.FromBytes);
+
+            return new Attachment(id, url, fileName, width, height, fileSize);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Channel.cs

@@ -0,0 +1,99 @@
+using System.Linq;
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+using Tyrrrz.Extensions;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#channel-object
+    public partial class Channel : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public ChannelType Type { get; }
+
+        public bool IsTextChannel => Type is
+            ChannelType.GuildTextChat or
+            ChannelType.DirectTextChat or
+            ChannelType.DirectGroupTextChat or
+            ChannelType.GuildNews or
+            ChannelType.GuildStore;
+
+        public bool IsVoiceChannel => !IsTextChannel;
+
+        public Snowflake GuildId { get; }
+
+        public ChannelCategory Category { get; }
+
+        public string Name { get; }
+
+        public int? Position { get; }
+
+        public string? Topic { get; }
+
+        public Channel(
+            Snowflake id,
+            ChannelType type,
+            Snowflake guildId,
+            ChannelCategory category,
+            string name,
+            int? position,
+            string? topic)
+        {
+            Id = id;
+            Type = type;
+            GuildId = guildId;
+            Category = category;
+            Name = name;
+            Position = position;
+            Topic = topic;
+        }
+
+        public override string ToString() => Name;
+    }
+
+    public partial class Channel
+    {
+        private static ChannelCategory GetFallbackCategory(ChannelType channelType) => new(
+            Snowflake.Zero,
+            channelType switch
+            {
+                ChannelType.GuildTextChat => "Text",
+                ChannelType.DirectTextChat => "Private",
+                ChannelType.DirectGroupTextChat => "Group",
+                ChannelType.GuildNews => "News",
+                ChannelType.GuildStore => "Store",
+                _ => "Default"
+            },
+            null
+        );
+
+        public static Channel Parse(JsonElement json, ChannelCategory? category = null, int? position = null)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+            var guildId = json.GetPropertyOrNull("guild_id")?.GetString().Pipe(Snowflake.Parse);
+            var topic = json.GetPropertyOrNull("topic")?.GetString();
+            var type = (ChannelType) json.GetProperty("type").GetInt32();
+
+            var name =
+                // Guild channel
+                json.GetPropertyOrNull("name")?.GetString() ??
+                // DM channel
+                json.GetPropertyOrNull("recipients")?.EnumerateArray().Select(User.Parse).Select(u => u.Name).JoinToString(", ") ??
+                // Fallback
+                id.ToString();
+
+            return new Channel(
+                id,
+                type,
+                guildId ?? Guild.DirectMessages.Id,
+                category ?? GetFallbackCategory(type),
+                name,
+                position ?? json.GetPropertyOrNull("position")?.GetInt32(),
+                topic
+            );
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/ChannelCategory.cs

@@ -0,0 +1,45 @@
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    public partial class ChannelCategory : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public string Name { get; }
+
+        public int? Position { get; }
+
+        public ChannelCategory(Snowflake id, string name, int? position)
+        {
+            Id = id;
+            Name = name;
+            Position = position;
+        }
+
+        public override string ToString() => Name;
+    }
+
+    public partial class ChannelCategory
+    {
+        public static ChannelCategory Parse(JsonElement json, int? position = null)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+
+            var name =
+                json.GetPropertyOrNull("name")?.GetString() ??
+                id.ToString();
+
+            return new ChannelCategory(
+                id,
+                name,
+                position ?? json.GetPropertyOrNull("position")?.GetInt32()
+            );
+        }
+
+        public static ChannelCategory Empty { get; } = new(Snowflake.Zero, "<unknown category>", 0);
+    }
+}

DiscordChatExporter.Core/Discord/Data/ChannelType.cs

@@ -0,0 +1,15 @@
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#channel-object-channel-types
+    // Order of enum fields needs to match the order in the docs.
+    public enum ChannelType
+    {
+        GuildTextChat = 0,
+        DirectTextChat,
+        GuildVoiceChat,
+        DirectGroupTextChat,
+        GuildCategory,
+        GuildNews,
+        GuildStore
+    }
+}

DiscordChatExporter.Core/Discord/Data/Common/FileSize.cs

@@ -0,0 +1,51 @@
+using System;
+
+namespace DiscordChatExporter.Core.Discord.Data.Common
+{
+    // Loosely based on https://github.com/omar/ByteSize (MIT license)
+    public readonly partial struct FileSize
+    {
+        public long TotalBytes { get; }
+
+        public double TotalKiloBytes => TotalBytes / 1024.0;
+        public double TotalMegaBytes => TotalKiloBytes / 1024.0;
+        public double TotalGigaBytes => TotalMegaBytes / 1024.0;
+
+        public FileSize(long bytes) => TotalBytes = bytes;
+
+        private double GetLargestWholeNumberValue()
+        {
+            if (Math.Abs(TotalGigaBytes) >= 1)
+                return TotalGigaBytes;
+
+            if (Math.Abs(TotalMegaBytes) >= 1)
+                return TotalMegaBytes;
+
+            if (Math.Abs(TotalKiloBytes) >= 1)
+                return TotalKiloBytes;
+
+            return TotalBytes;
+        }
+
+        private string GetLargestWholeNumberSymbol()
+        {
+            if (Math.Abs(TotalGigaBytes) >= 1)
+                return "GB";
+
+            if (Math.Abs(TotalMegaBytes) >= 1)
+                return "MB";
+
+            if (Math.Abs(TotalKiloBytes) >= 1)
+                return "KB";
+
+            return "bytes";
+        }
+
+        public override string ToString() => $"{GetLargestWholeNumberValue():0.##} {GetLargestWholeNumberSymbol()}";
+    }
+
+    public partial struct FileSize
+    {
+        public static FileSize FromBytes(long bytes) => new(bytes);
+    }
+}

DiscordChatExporter.Core/Discord/Data/Common/IHasId.cs

@@ -0,0 +1,7 @@
+namespace DiscordChatExporter.Core.Discord.Data.Common
+{
+    public interface IHasId
+    {
+        Snowflake Id { get; }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Common/IdBasedEqualityComparer.cs

@@ -0,0 +1,16 @@
+using System.Collections.Generic;
+
+namespace DiscordChatExporter.Core.Discord.Data.Common
+{
+    public partial class IdBasedEqualityComparer : IEqualityComparer<IHasId>
+    {
+        public bool Equals(IHasId? x, IHasId? y) => x?.Id == y?.Id;
+
+        public int GetHashCode(IHasId obj) => obj.Id.GetHashCode();
+    }
+
+    public partial class IdBasedEqualityComparer
+    {
+        public static IdBasedEqualityComparer Instance { get; } = new();
+    }
+}

DiscordChatExporter.Core/Discord/Data/Embed.cs

@@ -0,0 +1,96 @@
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.Linq;
+using System.Text.Json;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#embed-object
+    public partial class Embed
+    {
+        public string? Title { get; }
+
+        public string? Url { get; }
+
+        public DateTimeOffset? Timestamp { get; }
+
+        public Color? Color { get; }
+
+        public EmbedAuthor? Author { get; }
+
+        public string? Description { get; }
+
+        public IReadOnlyList<EmbedField> Fields { get; }
+
+        public EmbedImage? Thumbnail { get; }
+
+        public EmbedImage? Image { get; }
+
+        public EmbedFooter? Footer { get; }
+
+        public Embed(
+            string? title,
+            string? url,
+            DateTimeOffset? timestamp,
+            Color? color,
+            EmbedAuthor? author,
+            string? description,
+            IReadOnlyList<EmbedField> fields,
+            EmbedImage? thumbnail,
+            EmbedImage? image,
+            EmbedFooter? footer)
+        {
+            Title = title;
+            Url = url;
+            Timestamp = timestamp;
+            Color = color;
+            Author = author;
+            Description = description;
+            Fields = fields;
+            Thumbnail = thumbnail;
+            Image = image;
+            Footer = footer;
+        }
+
+        public YouTubeVideoEmbedProjection? TryGetYouTubeVideo() => YouTubeVideoEmbedProjection.TryResolve(this);
+
+        public override string ToString() => Title ?? "<untitled embed>";
+    }
+
+    public partial class Embed
+    {
+        public static Embed Parse(JsonElement json)
+        {
+            var title = json.GetPropertyOrNull("title")?.GetString();
+            var url = json.GetPropertyOrNull("url")?.GetString();
+            var timestamp = json.GetPropertyOrNull("timestamp")?.GetDateTimeOffset();
+            var color = json.GetPropertyOrNull("color")?.GetInt32().Pipe(System.Drawing.Color.FromArgb).ResetAlpha();
+            var description = json.GetPropertyOrNull("description")?.GetString();
+
+            var author = json.GetPropertyOrNull("author")?.Pipe(EmbedAuthor.Parse);
+            var thumbnail = json.GetPropertyOrNull("thumbnail")?.Pipe(EmbedImage.Parse);
+            var image = json.GetPropertyOrNull("image")?.Pipe(EmbedImage.Parse);
+            var footer = json.GetPropertyOrNull("footer")?.Pipe(EmbedFooter.Parse);
+
+            var fields =
+                json.GetPropertyOrNull("fields")?.EnumerateArray().Select(EmbedField.Parse).ToArray() ??
+                Array.Empty<EmbedField>();
+
+            return new Embed(
+                title,
+                url,
+                timestamp,
+                color,
+                author,
+                description,
+                fields,
+                thumbnail,
+                image,
+                footer
+            );
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/EmbedAuthor.cs

@@ -0,0 +1,40 @@
+using System.Text.Json;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#embed-object-embed-author-structure
+    public partial class EmbedAuthor
+    {
+        public string? Name { get; }
+
+        public string? Url { get; }
+
+        public string? IconUrl { get; }
+
+        public string? IconProxyUrl { get; }
+
+        public EmbedAuthor(string? name, string? url, string? iconUrl, string? iconProxyUrl)
+        {
+            Name = name;
+            Url = url;
+            IconUrl = iconUrl;
+            IconProxyUrl = iconProxyUrl;
+        }
+
+        public override string ToString() => Name ?? "<unnamed author>";
+    }
+
+    public partial class EmbedAuthor
+    {
+        public static EmbedAuthor Parse(JsonElement json)
+        {
+            var name = json.GetPropertyOrNull("name")?.GetString();
+            var url = json.GetPropertyOrNull("url")?.GetString();
+            var iconUrl = json.GetPropertyOrNull("icon_url")?.GetString();
+            var iconProxyUrl = json.GetPropertyOrNull("proxy_icon_url")?.GetString();
+
+            return new EmbedAuthor(name, url, iconUrl, iconProxyUrl);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/EmbedField.cs

@@ -0,0 +1,36 @@
+using System.Text.Json;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#embed-object-embed-field-structure
+    public partial class EmbedField
+    {
+        public string Name { get; }
+
+        public string Value { get; }
+
+        public bool IsInline { get; }
+
+        public EmbedField(string name, string value, bool isInline)
+        {
+            Name = name;
+            Value = value;
+            IsInline = isInline;
+        }
+
+        public override string ToString() => $"{Name} | {Value}";
+    }
+
+    public partial class EmbedField
+    {
+        public static EmbedField Parse(JsonElement json)
+        {
+            var name = json.GetProperty("name").GetString();
+            var value = json.GetProperty("value").GetString();
+            var isInline = json.GetPropertyOrNull("inline")?.GetBoolean() ?? false;
+
+            return new EmbedField(name, value, isInline);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/EmbedFooter.cs

@@ -0,0 +1,36 @@
+using System.Text.Json;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#embed-object-embed-footer-structure
+    public partial class EmbedFooter
+    {
+        public string Text { get; }
+
+        public string? IconUrl { get; }
+
+        public string? IconProxyUrl { get; }
+
+        public EmbedFooter(string text, string? iconUrl, string? iconProxyUrl)
+        {
+            Text = text;
+            IconUrl = iconUrl;
+            IconProxyUrl = iconProxyUrl;
+        }
+
+        public override string ToString() => Text;
+    }
+
+    public partial class EmbedFooter
+    {
+        public static EmbedFooter Parse(JsonElement json)
+        {
+            var text = json.GetProperty("text").GetString();
+            var iconUrl = json.GetPropertyOrNull("icon_url")?.GetString();
+            var iconProxyUrl = json.GetPropertyOrNull("proxy_icon_url")?.GetString();
+
+            return new EmbedFooter(text, iconUrl, iconProxyUrl);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/EmbedImage.cs

@@ -0,0 +1,38 @@
+using System.Text.Json;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#embed-object-embed-image-structure
+    public partial class EmbedImage
+    {
+        public string? Url { get; }
+
+        public string? ProxyUrl { get; }
+
+        public int? Width { get; }
+
+        public int? Height { get; }
+
+        public EmbedImage(string? url, string? proxyUrl, int? width, int? height)
+        {
+            Url = url;
+            ProxyUrl = proxyUrl;
+            Height = height;
+            Width = width;
+        }
+    }
+
+    public partial class EmbedImage
+    {
+        public static EmbedImage Parse(JsonElement json)
+        {
+            var url = json.GetPropertyOrNull("url")?.GetString();
+            var proxyUrl = json.GetPropertyOrNull("proxy_url")?.GetString();
+            var width = json.GetPropertyOrNull("width")?.GetInt32();
+            var height = json.GetPropertyOrNull("height")?.GetInt32();
+
+            return new EmbedImage(url, proxyUrl, width, height);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Emoji.cs

@@ -0,0 +1,74 @@
+using System.Linq;
+using System.Text.Json;
+using DiscordChatExporter.Core.Utils;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+using Tyrrrz.Extensions;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/emoji#emoji-object
+    public partial class Emoji
+    {
+        // Only present on custom emoji
+        public string? Id { get; }
+
+        // Name of custom emoji (e.g. LUL) or actual representation of standard emoji (e.g. 🙂)
+        public string Name { get; }
+
+        // Name of custom emoji (e.g. LUL) or name of standard emoji (e.g. slight_smile)
+        public string Code => !string.IsNullOrWhiteSpace(Id)
+            ? Name
+            : EmojiIndex.TryGetCode(Name) ?? Name;
+
+        public bool IsAnimated { get; }
+
+        public string ImageUrl { get; }
+
+        public Emoji(string? id, string name, bool isAnimated, string imageUrl)
+        {
+            Id = id;
+            Name = name;
+            IsAnimated = isAnimated;
+            ImageUrl = imageUrl;
+        }
+
+        public override string ToString() => Name;
+    }
+
+    public partial class Emoji
+    {
+        private static string GetTwemojiName(string name) => name
+            .GetRunes()
+            // Variant selector rune is skipped in Twemoji names
+            .Where(r => r.Value != 0xfe0f)
+            .Select(r => r.Value.ToString("x"))
+            .JoinToString("-");
+
+        public static string GetImageUrl(string? id, string name, bool isAnimated)
+        {
+            // Custom emoji
+            if (!string.IsNullOrWhiteSpace(id))
+            {
+                return isAnimated
+                    ? $"https://cdn.discordapp.com/emojis/{id}.gif"
+                    : $"https://cdn.discordapp.com/emojis/{id}.png";
+            }
+
+            // Standard emoji
+            var twemojiName = GetTwemojiName(name);
+            return $"https://twemoji.maxcdn.com/2/svg/{twemojiName}.svg";
+        }
+
+        public static Emoji Parse(JsonElement json)
+        {
+            var id = json.GetPropertyOrNull("id")?.GetString();
+            var name = json.GetProperty("name").GetString();
+            var isAnimated = json.GetPropertyOrNull("animated")?.GetBoolean() ?? false;
+
+            var imageUrl = GetImageUrl(id, name, isAnimated);
+
+            return new Emoji(id, name, isAnimated, imageUrl);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Guild.cs

@@ -0,0 +1,53 @@
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/guild#guild-object
+    public partial class Guild : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public string Name { get; }
+
+        public string IconUrl { get; }
+
+        public Guild(Snowflake id, string name, string iconUrl)
+        {
+            Id = id;
+            Name = name;
+            IconUrl = iconUrl;
+        }
+
+        public override string ToString() => Name;
+    }
+
+    public partial class Guild
+    {
+        public static Guild DirectMessages { get; } = new(
+            Snowflake.Zero,
+            "Direct Messages",
+            GetDefaultIconUrl()
+        );
+
+        private static string GetDefaultIconUrl() =>
+            "https://cdn.discordapp.com/embed/avatars/0.png";
+
+        private static string GetIconUrl(Snowflake id, string iconHash) =>
+            $"https://cdn.discordapp.com/icons/{id}/{iconHash}.png";
+
+        public static Guild Parse(JsonElement json)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+            var name = json.GetProperty("name").GetString();
+            var iconHash = json.GetProperty("icon").GetString();
+
+            var iconUrl = !string.IsNullOrWhiteSpace(iconHash)
+                ? GetIconUrl(id, iconHash)
+                : GetDefaultIconUrl();
+
+            return new Guild(id, name, iconUrl);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Member.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/guild#guild-member-object
+    public partial class Member : IHasId
+    {
+        public Snowflake Id => User.Id;
+
+        public User User { get; }
+
+        public string Nick { get; }
+
+        public IReadOnlyList<Snowflake> RoleIds { get; }
+
+        public Member(User user, string nick, IReadOnlyList<Snowflake> roleIds)
+        {
+            User = user;
+            Nick = nick;
+            RoleIds = roleIds;
+        }
+
+        public override string ToString() => Nick;
+    }
+
+    public partial class Member
+    {
+        public static Member CreateForUser(User user) => new(
+            user,
+            user.Name,
+            Array.Empty<Snowflake>()
+        );
+
+        public static Member Parse(JsonElement json)
+        {
+            var user = json.GetProperty("user").Pipe(User.Parse);
+            var nick = json.GetPropertyOrNull("nick")?.GetString();
+
+            var roleIds =
+                json.GetPropertyOrNull("roles")?.EnumerateArray().Select(j => j.GetString()).Select(Snowflake.Parse).ToArray() ??
+                Array.Empty<Snowflake>();
+
+            return new Member(
+                user,
+                nick ?? user.Name,
+                roleIds
+            );
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Message.cs

@@ -0,0 +1,152 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#message-object-message-types
+    public enum MessageType
+    {
+        Default = 0,
+        RecipientAdd = 1,
+        RecipientRemove = 2,
+        Call = 3,
+        ChannelNameChange = 4,
+        ChannelIconChange = 5,
+        ChannelPinnedMessage = 6,
+        GuildMemberJoin = 7,
+        Reply = 19
+    }
+
+    // https://discord.com/developers/docs/resources/channel#message-object
+    public partial class Message : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public MessageType Type { get; }
+
+        public User Author { get; }
+
+        public DateTimeOffset Timestamp { get; }
+
+        public DateTimeOffset? EditedTimestamp { get; }
+
+        public DateTimeOffset? CallEndedTimestamp { get; }
+
+        public bool IsPinned { get; }
+
+        public string Content { get; }
+
+        public IReadOnlyList<Attachment> Attachments { get; }
+
+        public IReadOnlyList<Embed> Embeds { get; }
+
+        public IReadOnlyList<Reaction> Reactions { get; }
+
+        public IReadOnlyList<User> MentionedUsers { get; }
+
+        public MessageReference? Reference { get; }
+
+        public Message? ReferencedMessage { get; }
+
+        public Message(
+            Snowflake id,
+            MessageType type,
+            User author,
+            DateTimeOffset timestamp,
+            DateTimeOffset? editedTimestamp,
+            DateTimeOffset? callEndedTimestamp,
+            bool isPinned,
+            string content,
+            IReadOnlyList<Attachment> attachments,
+            IReadOnlyList<Embed> embeds,
+            IReadOnlyList<Reaction> reactions,
+            IReadOnlyList<User> mentionedUsers,
+            MessageReference? messageReference,
+            Message? referencedMessage)
+        {
+            Id = id;
+            Type = type;
+            Author = author;
+            Timestamp = timestamp;
+            EditedTimestamp = editedTimestamp;
+            CallEndedTimestamp = callEndedTimestamp;
+            IsPinned = isPinned;
+            Content = content;
+            Attachments = attachments;
+            Embeds = embeds;
+            Reactions = reactions;
+            MentionedUsers = mentionedUsers;
+            Reference = messageReference;
+            ReferencedMessage = referencedMessage;
+        }
+
+        public override string ToString() => Content;
+    }
+
+    public partial class Message
+    {
+        public static Message Parse(JsonElement json)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+            var author = json.GetProperty("author").Pipe(User.Parse);
+            var timestamp = json.GetProperty("timestamp").GetDateTimeOffset();
+            var editedTimestamp = json.GetPropertyOrNull("edited_timestamp")?.GetDateTimeOffset();
+            var callEndedTimestamp = json.GetPropertyOrNull("call")?.GetPropertyOrNull("ended_timestamp")?.GetDateTimeOffset();
+            var type = (MessageType) json.GetProperty("type").GetInt32();
+            var isPinned = json.GetPropertyOrNull("pinned")?.GetBoolean() ?? false;
+            var messageReference = json.GetPropertyOrNull("message_reference")?.Pipe(MessageReference.Parse);
+            var referencedMessage = json.GetPropertyOrNull("referenced_message")?.Pipe(Parse);
+
+            var content = type switch
+            {
+                MessageType.RecipientAdd => "Added a recipient.",
+                MessageType.RecipientRemove => "Removed a recipient.",
+                MessageType.Call =>
+                    $"Started a call that lasted {callEndedTimestamp?.Pipe(t => t - timestamp).Pipe(t => (int) t.TotalMinutes) ?? 0} minutes.",
+                MessageType.ChannelNameChange => "Changed the channel name.",
+                MessageType.ChannelIconChange => "Changed the channel icon.",
+                MessageType.ChannelPinnedMessage => "Pinned a message.",
+                MessageType.GuildMemberJoin => "Joined the server.",
+                _ => json.GetPropertyOrNull("content")?.GetString() ?? ""
+            };
+
+            var attachments =
+                json.GetPropertyOrNull("attachments")?.EnumerateArray().Select(Attachment.Parse).ToArray() ??
+                Array.Empty<Attachment>();
+
+            var embeds =
+                json.GetPropertyOrNull("embeds")?.EnumerateArray().Select(Embed.Parse).ToArray() ??
+                Array.Empty<Embed>();
+
+            var reactions =
+                json.GetPropertyOrNull("reactions")?.EnumerateArray().Select(Reaction.Parse).ToArray() ??
+                Array.Empty<Reaction>();
+
+            var mentionedUsers =
+                json.GetPropertyOrNull("mentions")?.EnumerateArray().Select(User.Parse).ToArray() ??
+                Array.Empty<User>();
+
+            return new Message(
+                id,
+                type,
+                author,
+                timestamp,
+                editedTimestamp,
+                callEndedTimestamp,
+                isPinned,
+                content,
+                attachments,
+                embeds,
+                reactions,
+                mentionedUsers,
+                messageReference,
+                referencedMessage
+            );
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/MessageReference.cs

@@ -0,0 +1,37 @@
+using System.Text.Json;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#message-object-message-reference-structure
+    public partial class MessageReference
+    {
+        public Snowflake? MessageId { get; }
+
+        public Snowflake? ChannelId { get; }
+
+        public Snowflake? GuildId { get; }
+
+        public MessageReference(Snowflake? messageId, Snowflake? channelId, Snowflake? guildId)
+        {
+            MessageId = messageId;
+            ChannelId = channelId;
+            GuildId = guildId;
+        }
+
+        public override string ToString() => MessageId?.ToString() ?? "<unknown reference>";
+    }
+
+    public partial class MessageReference
+    {
+        public static MessageReference Parse(JsonElement json)
+        {
+            var messageId = json.GetPropertyOrNull("message_id")?.GetString().Pipe(Snowflake.Parse);
+            var channelId = json.GetPropertyOrNull("channel_id")?.GetString().Pipe(Snowflake.Parse);
+            var guildId = json.GetPropertyOrNull("guild_id")?.GetString().Pipe(Snowflake.Parse);
+
+            return new MessageReference(messageId, channelId, guildId);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Reaction.cs

@@ -0,0 +1,32 @@
+using System.Text.Json;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/channel#reaction-object
+    public partial class Reaction
+    {
+        public Emoji Emoji { get; }
+
+        public int Count { get; }
+
+        public Reaction(Emoji emoji, int count)
+        {
+            Emoji = emoji;
+            Count = count;
+        }
+
+        public override string ToString() => $"{Emoji} ({Count})";
+    }
+
+    public partial class Reaction
+    {
+        public static Reaction Parse(JsonElement json)
+        {
+            var emoji = json.GetProperty("emoji").Pipe(Emoji.Parse);
+            var count = json.GetProperty("count").GetInt32();
+
+            return new Reaction(emoji, count);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/Role.cs

@@ -0,0 +1,53 @@
+using System.Drawing;
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/topics/permissions#role-object
+    public partial class Role : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public string Name { get; }
+
+        public int Position { get; }
+
+        public Color? Color { get; }
+
+        public Role(
+            Snowflake id,
+            string name,
+            int position,
+            Color? color)
+        {
+            Id = id;
+            Name = name;
+            Position = position;
+            Color = color;
+        }
+
+        public override string ToString() => Name;
+    }
+
+    public partial class Role
+    {
+        public static Role Parse(JsonElement json)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+            var name = json.GetProperty("name").GetString();
+            var position = json.GetProperty("position").GetInt32();
+
+            var color = json
+                .GetPropertyOrNull("color")?
+                .GetInt32()
+                .Pipe(System.Drawing.Color.FromArgb)
+                .ResetAlpha()
+                .NullIf(c => c.ToRgb() <= 0);
+
+            return new Role(id, name, position, color);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/User.cs

@@ -0,0 +1,73 @@
+using System;
+using System.Text.Json;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    // https://discord.com/developers/docs/resources/user#user-object
+    public partial class User : IHasId
+    {
+        public Snowflake Id { get; }
+
+        public bool IsBot { get; }
+
+        public int Discriminator { get; }
+
+        public string DiscriminatorFormatted => $"{Discriminator:0000}";
+
+        public string Name { get; }
+
+        public string FullName => $"{Name}#{DiscriminatorFormatted}";
+
+        public string AvatarUrl { get; }
+
+        public User(
+            Snowflake id,
+            bool isBot,
+            int discriminator,
+            string name,
+            string avatarUrl)
+        {
+            Id = id;
+            IsBot = isBot;
+            Discriminator = discriminator;
+            Name = name;
+            AvatarUrl = avatarUrl;
+        }
+
+        public override string ToString() => FullName;
+    }
+
+    public partial class User
+    {
+        private static string GetDefaultAvatarUrl(int discriminator) =>
+            $"https://cdn.discordapp.com/embed/avatars/{discriminator % 5}.png";
+
+        private static string GetAvatarUrl(Snowflake id, string avatarHash)
+        {
+            // Animated
+            if (avatarHash.StartsWith("a_", StringComparison.Ordinal))
+                return $"https://cdn.discordapp.com/avatars/{id}/{avatarHash}.gif?size=40";
+
+            // Non-animated
+            return $"https://cdn.discordapp.com/avatars/{id}/{avatarHash}.png?size=40";
+        }
+
+        public static User Parse(JsonElement json)
+        {
+            var id = json.GetProperty("id").GetString().Pipe(Snowflake.Parse);
+            var isBot = json.GetPropertyOrNull("bot")?.GetBoolean() ?? false;
+            var discriminator = json.GetProperty("discriminator").GetString().Pipe(int.Parse);
+            var name = json.GetProperty("username").GetString();
+            var avatarHash = json.GetProperty("avatar").GetString();
+
+            var avatarUrl = !string.IsNullOrWhiteSpace(avatarHash)
+                ? GetAvatarUrl(id, avatarHash)
+                : GetDefaultAvatarUrl(discriminator);
+
+            return new User(id, isBot, discriminator, name, avatarUrl);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Data/YouTubeVideoEmbedProjection.cs

@@ -0,0 +1,61 @@
+using System.Text.RegularExpressions;
+
+namespace DiscordChatExporter.Core.Discord.Data
+{
+    public partial class YouTubeVideoEmbedProjection
+    {
+        public string VideoId { get; }
+
+        public string Url { get; }
+
+        public YouTubeVideoEmbedProjection(string videoId, string url)
+        {
+            VideoId = videoId;
+            Url = url;
+        }
+
+        public override string ToString() => Url;
+    }
+
+    public partial class YouTubeVideoEmbedProjection
+    {
+        // Adapted from YoutubeExplode
+        // https://github.com/Tyrrrz/YoutubeExplode/blob/5be164be20019783913f76fcc98f18c65aebe9f0/YoutubeExplode/Videos/VideoId.cs#L34-L64
+        private static string? TryParseVideoId(string embedUrl)
+        {
+            // Regular URL
+            // https://www.youtube.com/watch?v=yIVRs6YSbOM
+            var regularMatch = Regex.Match(embedUrl, @"youtube\..+?/watch.*?v=(.*?)(?:&|/|$)").Groups[1].Value;
+            if (!string.IsNullOrWhiteSpace(regularMatch))
+                return regularMatch;
+
+            // Short URL
+            // https://youtu.be/yIVRs6YSbOM
+            var shortMatch = Regex.Match(embedUrl, @"youtu\.be/(.*?)(?:\?|&|/|$)").Groups[1].Value;
+            if (!string.IsNullOrWhiteSpace(shortMatch))
+                return shortMatch;
+
+            // Embed URL
+            // https://www.youtube.com/embed/yIVRs6YSbOM
+            var embedMatch = Regex.Match(embedUrl, @"youtube\..+?/embed/(.*?)(?:\?|&|/|$)").Groups[1].Value;
+            if (!string.IsNullOrWhiteSpace(embedMatch))
+                return embedMatch;
+
+            return null;
+        }
+
+        public static YouTubeVideoEmbedProjection? TryResolve(Embed embed)
+        {
+            if (string.IsNullOrWhiteSpace(embed.Url))
+                return null;
+
+            var videoId = TryParseVideoId(embed.Url);
+            if (string.IsNullOrWhiteSpace(videoId))
+                return null;
+
+            var url = $"https://www.youtube.com/embed/{videoId}";
+
+            return new YouTubeVideoEmbedProjection(videoId, url);
+        }
+    }
+}

DiscordChatExporter.Core/Discord/DiscordClient.cs

@@ -0,0 +1,282 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Net.Http;
+using System.Text.Json;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Exceptions;
+using DiscordChatExporter.Core.Utils;
+using DiscordChatExporter.Core.Utils.Extensions;
+using JsonExtensions.Http;
+using JsonExtensions.Reading;
+
+namespace DiscordChatExporter.Core.Discord
+{
+    public class DiscordClient
+    {
+        private readonly HttpClient _httpClient;
+        private readonly AuthToken _token;
+
+        private readonly Uri _baseUri = new("https://discord.com/api/v8/", UriKind.Absolute);
+
+        public DiscordClient(HttpClient httpClient, AuthToken token)
+        {
+            _httpClient = httpClient;
+            _token = token;
+        }
+
+        public DiscordClient(AuthToken token)
+            : this(Http.Client, token)
+        {
+        }
+
+        private async ValueTask<HttpResponseMessage> GetResponseAsync(string url) =>
+            await Http.ResponsePolicy.ExecuteAsync(async () =>
+            {
+                using var request = new HttpRequestMessage(HttpMethod.Get, new Uri(_baseUri, url));
+                request.Headers.Authorization = _token.GetAuthenticationHeader();
+
+                return await _httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead);
+            });
+
+        private async ValueTask<JsonElement> GetJsonResponseAsync(string url)
+        {
+            using var response = await GetResponseAsync(url);
+
+            if (!response.IsSuccessStatusCode)
+            {
+                throw response.StatusCode switch
+                {
+                    HttpStatusCode.Unauthorized => DiscordChatExporterException.Unauthorized(),
+                    HttpStatusCode.Forbidden => DiscordChatExporterException.Forbidden(),
+                    HttpStatusCode.NotFound => DiscordChatExporterException.NotFound(url),
+                    _ => DiscordChatExporterException.FailedHttpRequest(response)
+                };
+            }
+
+            return await response.Content.ReadAsJsonAsync();
+        }
+
+        private async ValueTask<JsonElement?> TryGetJsonResponseAsync(string url)
+        {
+            using var response = await GetResponseAsync(url);
+
+            return response.IsSuccessStatusCode
+                ? await response.Content.ReadAsJsonAsync()
+                : null;
+        }
+
+        public async IAsyncEnumerable<Guild> GetUserGuildsAsync()
+        {
+            yield return Guild.DirectMessages;
+
+            var currentAfter = Snowflake.Zero;
+
+            while (true)
+            {
+                var url = new UrlBuilder()
+                    .SetPath("users/@me/guilds")
+                    .SetQueryParameter("limit", "100")
+                    .SetQueryParameter("after", currentAfter.ToString())
+                    .Build();
+
+                var response = await GetJsonResponseAsync(url);
+
+                var isEmpty = true;
+                foreach (var guild in response.EnumerateArray().Select(Guild.Parse))
+                {
+                    yield return guild;
+
+                    currentAfter = guild.Id;
+                    isEmpty = false;
+                }
+
+                if (isEmpty)
+                    yield break;
+            }
+        }
+
+        public async ValueTask<Guild> GetGuildAsync(Snowflake guildId)
+        {
+            if (guildId == Guild.DirectMessages.Id)
+                return Guild.DirectMessages;
+
+            var response = await GetJsonResponseAsync($"guilds/{guildId}");
+            return Guild.Parse(response);
+        }
+
+        public async IAsyncEnumerable<Channel> GetGuildChannelsAsync(Snowflake guildId)
+        {
+            if (guildId == Guild.DirectMessages.Id)
+            {
+                var response = await GetJsonResponseAsync("users/@me/channels");
+                foreach (var channelJson in response.EnumerateArray())
+                    yield return Channel.Parse(channelJson);
+            }
+            else
+            {
+                var response = await GetJsonResponseAsync($"guilds/{guildId}/channels");
+
+                var responseOrdered = response
+                    .EnumerateArray()
+                    .OrderBy(j => j.GetProperty("position").GetInt32())
+                    .ThenBy(j => Snowflake.Parse(j.GetProperty("id").GetString()))
+                    .ToArray();
+
+                var categories = responseOrdered
+                    .Where(j => j.GetProperty("type").GetInt32() == (int) ChannelType.GuildCategory)
+                    .Select((j, index) => ChannelCategory.Parse(j, index + 1))
+                    .ToDictionary(j => j.Id.ToString(), StringComparer.Ordinal);
+
+                var position = 0;
+
+                foreach (var channelJson in responseOrdered)
+                {
+                    var parentId = channelJson.GetPropertyOrNull("parent_id")?.GetString();
+
+                    var category = !string.IsNullOrWhiteSpace(parentId)
+                        ? categories.GetValueOrDefault(parentId)
+                        : null;
+
+                    var channel = Channel.Parse(channelJson, category, position);
+
+                    position++;
+
+                    yield return channel;
+                }
+            }
+        }
+
+        public async IAsyncEnumerable<Role> GetGuildRolesAsync(Snowflake guildId)
+        {
+            if (guildId == Guild.DirectMessages.Id)
+                yield break;
+
+            var response = await GetJsonResponseAsync($"guilds/{guildId}/roles");
+
+            foreach (var roleJson in response.EnumerateArray())
+                yield return Role.Parse(roleJson);
+        }
+
+        public async ValueTask<Member?> TryGetGuildMemberAsync(Snowflake guildId, User user)
+        {
+            if (guildId == Guild.DirectMessages.Id)
+                return Member.CreateForUser(user);
+
+            var response = await TryGetJsonResponseAsync($"guilds/{guildId}/members/{user.Id}");
+            return response?.Pipe(Member.Parse);
+        }
+
+        public async ValueTask<ChannelCategory> GetChannelCategoryAsync(Snowflake channelId)
+        {
+            try
+            {
+                var response = await GetJsonResponseAsync($"channels/{channelId}");
+                return ChannelCategory.Parse(response);
+            }
+            // In some cases, the Discord API returns an empty body when requesting channel category.
+            // Instead, we use an empty channel category as a fallback.
+            catch (DiscordChatExporterException)
+            {
+                return ChannelCategory.Empty;
+            }
+        }
+
+        public async ValueTask<Channel> GetChannelAsync(Snowflake channelId)
+        {
+            var response = await GetJsonResponseAsync($"channels/{channelId}");
+
+            var parentId = response.GetPropertyOrNull("parent_id")?.GetString().Pipe(Snowflake.Parse);
+
+            var category = parentId is not null
+                ? await GetChannelCategoryAsync(parentId.Value)
+                : null;
+
+            return Channel.Parse(response, category);
+        }
+
+        private async ValueTask<Message?> TryGetLastMessageAsync(Snowflake channelId, Snowflake? before = null)
+        {
+            var url = new UrlBuilder()
+                .SetPath($"channels/{channelId}/messages")
+                .SetQueryParameter("limit", "1")
+                .SetQueryParameter("before", before?.ToString())
+                .Build();
+
+            var response = await GetJsonResponseAsync(url);
+            return response.EnumerateArray().Select(Message.Parse).LastOrDefault();
+        }
+
+        public async IAsyncEnumerable<Message> GetMessagesAsync(
+            Snowflake channelId,
+            Snowflake? after = null,
+            Snowflake? before = null,
+            IProgress<double>? progress = null)
+        {
+            // Get the last message in the specified range.
+            // This snapshots the boundaries, which means that messages posted after the export started
+            // will not appear in the output.
+            // Additionally, it provides the date of the last message, which is used to calculate progress.
+            var lastMessage = await TryGetLastMessageAsync(channelId, before);
+            if (lastMessage is null || lastMessage.Timestamp < after?.ToDate())
+                yield break;
+
+            // Keep track of first message in range in order to calculate progress
+            var firstMessage = default(Message);
+            var currentAfter = after ?? Snowflake.Zero;
+
+            while (true)
+            {
+                var url = new UrlBuilder()
+                    .SetPath($"channels/{channelId}/messages")
+                    .SetQueryParameter("limit", "100")
+                    .SetQueryParameter("after", currentAfter.ToString())
+                    .Build();
+
+                var response = await GetJsonResponseAsync(url);
+
+                var messages = response
+                    .EnumerateArray()
+                    .Select(Message.Parse)
+                    .Reverse() // reverse because messages appear newest first
+                    .ToArray();
+
+                // Break if there are no messages (can happen if messages are deleted during execution)
+                if (!messages.Any())
+                    yield break;
+
+                foreach (var message in messages)
+                {
+                    firstMessage ??= message;
+
+                    // Ensure messages are in range (take into account that last message could have been deleted)
+                    if (message.Timestamp > lastMessage.Timestamp)
+                        yield break;
+
+                    // Report progress based on the duration of exported messages divided by total
+                    if (progress is not null)
+                    {
+                        var exportedDuration = (message.Timestamp - firstMessage.Timestamp).Duration();
+                        var totalDuration = (lastMessage.Timestamp - firstMessage.Timestamp).Duration();
+
+                        if (totalDuration > TimeSpan.Zero)
+                        {
+                            progress.Report(exportedDuration / totalDuration);
+                        }
+                        // Avoid division by zero if all messages have the exact same timestamp
+                        // (which may be the case if there's only one message in the channel)
+                        else
+                        {
+                            progress.Report(1);
+                        }
+                    }
+
+                    yield return message;
+                    currentAfter = message.Id;
+                }
+            }
+        }
+    }
+}

DiscordChatExporter.Core/Discord/Snowflake.cs

@@ -0,0 +1,71 @@
+using System;
+using System.Globalization;
+using System.Text.RegularExpressions;
+
+namespace DiscordChatExporter.Core.Discord
+{
+    public readonly partial struct Snowflake
+    {
+        public ulong Value { get; }
+
+        public Snowflake(ulong value) => Value = value;
+
+        public DateTimeOffset ToDate() => DateTimeOffset.FromUnixTimeMilliseconds(
+            (long) ((Value >> 22) + 1420070400000UL)
+        ).ToLocalTime();
+
+        public override string ToString() => Value.ToString(CultureInfo.InvariantCulture);
+    }
+
+    public partial struct Snowflake
+    {
+        public static Snowflake Zero { get; } = new(0);
+
+        public static Snowflake FromDate(DateTimeOffset date)
+        {
+            var value = ((ulong) date.ToUnixTimeMilliseconds() - 1420070400000UL) << 22;
+            return new Snowflake(value);
+        }
+
+        public static Snowflake? TryParse(string? str, IFormatProvider? formatProvider = null)
+        {
+            if (string.IsNullOrWhiteSpace(str))
+                return null;
+
+            // As number
+            if (Regex.IsMatch(str, @"^\d+$") &&
+                ulong.TryParse(str, NumberStyles.Number, formatProvider, out var value))
+            {
+                return new Snowflake(value);
+            }
+
+            // As date
+            if (DateTimeOffset.TryParse(str, formatProvider, DateTimeStyles.None, out var date))
+            {
+                return FromDate(date);
+            }
+
+            return null;
+        }
+
+        public static Snowflake Parse(string str, IFormatProvider? formatProvider) =>
+            TryParse(str, formatProvider) ?? throw new FormatException($"Invalid snowflake '{str}'.");
+
+        public static Snowflake Parse(string str) => Parse(str, null);
+    }
+
+    public partial struct Snowflake : IComparable<Snowflake>, IEquatable<Snowflake>
+    {
+        public int CompareTo(Snowflake other) => Value.CompareTo(other.Value);
+
+        public bool Equals(Snowflake other) => CompareTo(other) == 0;
+
+        public override bool Equals(object? obj) => obj is Snowflake other && Equals(other);
+
+        public override int GetHashCode() => Value.GetHashCode();
+
+        public static bool operator ==(Snowflake left, Snowflake right) => left.Equals(right);
+
+        public static bool operator !=(Snowflake left, Snowflake right) => !(left == right);
+    }
+}

DiscordChatExporter.Core/DiscordChatExporter.Core.csproj

@@ -1,36 +1,19 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
-    <PropertyGroup>
-        <TargetFramework>net461</TargetFramework>
-    </PropertyGroup>
+  <PropertyGroup>
+    <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
+  </PropertyGroup>
 
-    <ItemGroup>
-        <EmbeddedResource Include="Resources\ExportTemplates\PlainText\Template.txt" />
-        <EmbeddedResource Include="Resources\ExportTemplates\HtmlDark\Template.html" />
-        <EmbeddedResource Include="Resources\ExportTemplates\HtmlLight\Template.html" />
-        <EmbeddedResource Include="Resources\ExportTemplates\HtmlShared\Main.html" />
-        <EmbeddedResource Include="Resources\ExportTemplates\HtmlShared\Main.css" />
-        <EmbeddedResource Include="Resources\ExportTemplates\HtmlDark\Theme.css" />
-        <EmbeddedResource Include="Resources\ExportTemplates\HtmlLight\Theme.css" />
-        <EmbeddedResource Include="Resources\ExportTemplates\Csv\Template.csv" />
-    </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="JsonExtensions" Version="1.1.0" />
+    <PackageReference Include="MiniRazor.CodeGen" Version="2.1.2" />
+    <PackageReference Include="Polly" Version="7.2.2" />
+    <PackageReference Include="Superpower" Version="2.3.0" />
+    <PackageReference Include="Tyrrrz.Extensions" Version="1.6.5" />
+  </ItemGroup>
 
-    <ItemGroup>
-        <Reference Include="mscorlib" />
-    </ItemGroup>
-
-    <ItemGroup>
-        <PackageReference Include="ByteSize" Version="1.3.0" />
-        <PackageReference Include="Failsafe" Version="1.1.0" />
-        <PackageReference Include="Newtonsoft.Json" Version="12.0.1" />
-        <PackageReference Include="Onova" Version="2.2.0" />
-        <PackageReference Include="Scriban" Version="1.2.9" />
-        <PackageReference Include="Tyrrrz.Extensions" Version="1.5.1" />
-        <PackageReference Include="Tyrrrz.Settings" Version="1.3.3" />
-    </ItemGroup>
-
-    <ItemGroup>
-      <ProjectReference Include="..\DiscordChatExporter.Core.Markdown\DiscordChatExporter.Core.Markdown.csproj" />
-    </ItemGroup>
+  <ItemGroup>
+    <AdditionalFiles Include="Exporting\Writers\Html\*.cshtml" IsRazorTemplate="true" />
+  </ItemGroup>
 
 </Project>

DiscordChatExporter.Core/Exceptions/DiscordChatExporterException.cs

@@ -0,0 +1,45 @@
+using System;
+using System.Net.Http;
+
+namespace DiscordChatExporter.Core.Exceptions
+{
+    public partial class DiscordChatExporterException : Exception
+    {
+        public bool IsCritical { get; }
+
+        public DiscordChatExporterException(string message, bool isCritical = false)
+            : base(message)
+        {
+            IsCritical = isCritical;
+        }
+    }
+
+    public partial class DiscordChatExporterException
+    {
+        internal static DiscordChatExporterException FailedHttpRequest(HttpResponseMessage response)
+        {
+            var message = $@"
+Failed to perform an HTTP request.
+
+[Request]
+{response.RequestMessage}
+
+[Response]
+{response}";
+
+            return new DiscordChatExporterException(message.Trim(), true);
+        }
+
+        internal static DiscordChatExporterException Unauthorized() =>
+            new("Authentication token is invalid.");
+
+        internal static DiscordChatExporterException Forbidden() =>
+            new("Access is forbidden.");
+
+        internal static DiscordChatExporterException NotFound(string resourceId) =>
+            new($"Requested resource ({resourceId}) does not exist.");
+
+        internal static DiscordChatExporterException ChannelIsEmpty() =>
+            new("No messages found for the specified period.");
+    }
+}

DiscordChatExporter.Core/Exceptions/HttpErrorStatusCodeException.cs

@@ -1,19 +0,0 @@
-using System;
-using System.Net;
-
-namespace DiscordChatExporter.Core.Exceptions
-{
-    public class HttpErrorStatusCodeException : Exception
-    {
-        public HttpStatusCode StatusCode { get; }
-
-        public string ReasonPhrase { get; }
-
-        public HttpErrorStatusCodeException(HttpStatusCode statusCode, string reasonPhrase)
-            : base($"Error HTTP status code: {statusCode} - {reasonPhrase}")
-        {
-            StatusCode = statusCode;
-            ReasonPhrase = reasonPhrase;
-        }
-    }
-}

DiscordChatExporter.Core/Exporting/ChannelExporter.cs

@@ -0,0 +1,69 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Discord.Data.Common;
+using DiscordChatExporter.Core.Exceptions;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Core.Exporting
+{
+    public class ChannelExporter
+    {
+        private readonly DiscordClient _discord;
+
+        public ChannelExporter(DiscordClient discord) => _discord = discord;
+
+        public ChannelExporter(AuthToken token) : this(new DiscordClient(token)) {}
+
+        public async ValueTask ExportChannelAsync(ExportRequest request, IProgress<double>? progress = null)
+        {
+            // Build context
+            var contextMembers = new HashSet<Member>(IdBasedEqualityComparer.Instance);
+            var contextChannels = await _discord.GetGuildChannelsAsync(request.Guild.Id);
+            var contextRoles = await _discord.GetGuildRolesAsync(request.Guild.Id);
+
+            var context = new ExportContext(
+                request,
+                contextMembers,
+                contextChannels,
+                contextRoles
+            );
+
+            // Export messages
+            await using var messageExporter = new MessageExporter(context);
+
+            var exportedAnything = false;
+            var encounteredUsers = new HashSet<User>(IdBasedEqualityComparer.Instance);
+            await foreach (var message in _discord.GetMessagesAsync(request.Channel.Id, request.After, request.Before, progress))
+            {
+                // Skips any messages that fail to pass the supplied filter
+                if (!request.MessageFilter.Filter(message))
+                    continue;
+
+                // Resolve members for referenced users
+                foreach (var referencedUser in message.MentionedUsers.Prepend(message.Author))
+                {
+                    if (!encounteredUsers.Add(referencedUser))
+                        continue;
+
+                    var member =
+                        await _discord.TryGetGuildMemberAsync(request.Guild.Id, referencedUser) ??
+                        Member.CreateForUser(referencedUser);
+
+                    contextMembers.Add(member);
+                }
+
+                // Export message
+                await messageExporter.ExportMessageAsync(message);
+                exportedAnything = true;
+            }
+
+            // Throw if no messages were exported
+            if (!exportedAnything)
+                throw DiscordChatExporterException.ChannelIsEmpty();
+        }
+    }
+}

DiscordChatExporter.Core/Exporting/ExportContext.cs

@@ -0,0 +1,104 @@
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+using System.IO;
+using System.Linq;
+using System.Net.Http;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Utils.Extensions;
+using Tyrrrz.Extensions;
+
+namespace DiscordChatExporter.Core.Exporting
+{
+    internal class ExportContext
+    {
+        private readonly MediaDownloader _mediaDownloader;
+
+        public ExportRequest Request { get; }
+
+        public IReadOnlyCollection<Member> Members { get; }
+
+        public IReadOnlyCollection<Channel> Channels { get; }
+
+        public IReadOnlyCollection<Role> Roles { get; }
+
+        public ExportContext(
+            ExportRequest request,
+            IReadOnlyCollection<Member> members,
+            IReadOnlyCollection<Channel> channels,
+            IReadOnlyCollection<Role> roles)
+        {
+            Request = request;
+            Members = members;
+            Channels = channels;
+            Roles = roles;
+
+            _mediaDownloader = new MediaDownloader(request.OutputMediaDirPath, request.ShouldReuseMedia);
+        }
+
+        public string FormatDate(DateTimeOffset date) => Request.DateFormat switch
+        {
+            "unix" => date.ToUnixTimeSeconds().ToString(),
+            "unixms" => date.ToUnixTimeMilliseconds().ToString(),
+            var dateFormat => date.ToLocalString(dateFormat)
+        };
+
+        public Member? TryGetMember(Snowflake id) => Members.FirstOrDefault(m => m.Id == id);
+
+        public Channel? TryGetChannel(Snowflake id) => Channels.FirstOrDefault(c => c.Id == id);
+
+        public Role? TryGetRole(Snowflake id) => Roles.FirstOrDefault(r => r.Id == id);
+
+        public Color? TryGetUserColor(Snowflake id)
+        {
+            var member = TryGetMember(id);
+            var roles = member?.RoleIds.Join(Roles, i => i, r => r.Id, (_, role) => role);
+
+            return roles?
+                .Where(r => r.Color is not null)
+                .OrderByDescending(r => r.Position)
+                .Select(r => r.Color)
+                .FirstOrDefault();
+        }
+
+        public async ValueTask<string> ResolveMediaUrlAsync(string url)
+        {
+            if (!Request.ShouldDownloadMedia)
+                return url;
+
+            try
+            {
+                var filePath = await _mediaDownloader.DownloadAsync(url);
+
+                // We want relative path so that the output files can be copied around without breaking.
+                // Base directory path may be null if the file is stored at the root or relative to working directory.
+                var relativeFilePath = !string.IsNullOrWhiteSpace(Request.OutputBaseDirPath)
+                    ? Path.GetRelativePath(Request.OutputBaseDirPath, filePath)
+                    : filePath;
+
+                // HACK: for HTML, we need to format the URL properly
+                if (Request.Format is ExportFormat.HtmlDark or ExportFormat.HtmlLight)
+                {
+                    // Need to escape each path segment while keeping the directory separators intact
+                    return relativeFilePath
+                        .Split(Path.DirectorySeparatorChar, Path.AltDirectorySeparatorChar)
+                        .Select(Uri.EscapeDataString)
+                        .JoinToString(Path.AltDirectorySeparatorChar.ToString());
+                }
+
+                return relativeFilePath;
+            }
+            // Try to catch only exceptions related to failed HTTP requests
+            // https://github.com/Tyrrrz/DiscordChatExporter/issues/332
+            // https://github.com/Tyrrrz/DiscordChatExporter/issues/372
+            catch (Exception ex) when (ex is HttpRequestException or OperationCanceledException)
+            {
+                // TODO: add logging so we can be more liberal with catching exceptions
+                // We don't want this to crash the exporting process in case of failure
+                return url;
+            }
+        }
+    }
+}

DiscordChatExporter.Core/Exporting/ExportFormat.cs

@@ -0,0 +1,36 @@
+using System;
+
+namespace DiscordChatExporter.Core.Exporting
+{
+    public enum ExportFormat
+    {
+        PlainText,
+        HtmlDark,
+        HtmlLight,
+        Csv,
+        Json
+    }
+
+    public static class ExportFormatExtensions
+    {
+        public static string GetFileExtension(this ExportFormat format) => format switch
+        {
+            ExportFormat.PlainText => "txt",
+            ExportFormat.HtmlDark => "html",
+            ExportFormat.HtmlLight => "html",
+            ExportFormat.Csv => "csv",
+            ExportFormat.Json => "json",
+            _ => throw new ArgumentOutOfRangeException(nameof(format))
+        };
+
+        public static string GetDisplayName(this ExportFormat format) => format switch
+        {
+            ExportFormat.PlainText => "TXT",
+            ExportFormat.HtmlDark => "HTML (Dark)",
+            ExportFormat.HtmlLight => "HTML (Light)",
+            ExportFormat.Csv => "CSV",
+            ExportFormat.Json => "JSON",
+            _ => throw new ArgumentOutOfRangeException(nameof(format))
+        };
+    }
+}

DiscordChatExporter.Core/Exporting/ExportRequest.cs

@@ -0,0 +1,168 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Text.RegularExpressions;
+using DiscordChatExporter.Core.Discord;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Exporting.Filtering;
+using DiscordChatExporter.Core.Exporting.Partitioning;
+using DiscordChatExporter.Core.Utils;
+
+namespace DiscordChatExporter.Core.Exporting
+{
+    public partial class ExportRequest
+    {
+        public Guild Guild { get; }
+
+        public Channel Channel { get; }
+
+        public string OutputPath { get; }
+
+        public string OutputBaseFilePath { get; }
+
+        public string OutputBaseDirPath { get; }
+
+        public string OutputMediaDirPath { get; }
+
+        public ExportFormat Format { get; }
+
+        public Snowflake? After { get; }
+
+        public Snowflake? Before { get; }
+
+        public PartitionLimit PartitionLimit { get; }
+
+        public MessageFilter MessageFilter { get; }
+
+        public bool ShouldDownloadMedia { get; }
+
+        public bool ShouldReuseMedia { get; }
+
+        public string DateFormat { get; }
+
+        public ExportRequest(
+            Guild guild,
+            Channel channel,
+            string outputPath,
+            ExportFormat format,
+            Snowflake? after,
+            Snowflake? before,
+            PartitionLimit partitionLimit,
+            MessageFilter messageFilter,
+            bool shouldDownloadMedia,
+            bool shouldReuseMedia,
+            string dateFormat)
+        {
+            Guild = guild;
+            Channel = channel;
+            OutputPath = outputPath;
+            Format = format;
+            After = after;
+            Before = before;
+            PartitionLimit = partitionLimit;
+            MessageFilter = messageFilter;
+            ShouldDownloadMedia = shouldDownloadMedia;
+            ShouldReuseMedia = shouldReuseMedia;
+            DateFormat = dateFormat;
+
+            OutputBaseFilePath = GetOutputBaseFilePath(
+                guild,
+                channel,
+                outputPath,
+                format,
+                after,
+                before
+            );
+
+            OutputBaseDirPath = Path.GetDirectoryName(OutputBaseFilePath) ?? OutputPath;
+            OutputMediaDirPath = $"{OutputBaseFilePath}_Files{Path.DirectorySeparatorChar}";
+        }
+    }
+
+    public partial class ExportRequest
+    {
+        private static string GetOutputBaseFilePath(
+            Guild guild,
+            Channel channel,
+            string outputPath,
+            ExportFormat format,
+            Snowflake? after = null,
+            Snowflake? before = null)
+        {
+
+            // Formats path
+            outputPath = Regex.Replace(outputPath, "%.", m =>
+                PathEx.EscapePath(m.Value switch
+                {
+                    "%g" => guild.Id.ToString(),
+                    "%G" => guild.Name,
+                    "%t" => channel.Category.Id.ToString(),
+                    "%T" => channel.Category.Name,
+                    "%c" => channel.Id.ToString(),
+                    "%C" => channel.Name,
+                    "%p" => channel.Position?.ToString() ?? "0",
+                    "%P" => channel.Category.Position?.ToString() ?? "0",
+                    "%a" => (after ?? Snowflake.Zero).ToDate().ToString("yyyy-MM-dd"),
+                    "%b" => (before?.ToDate() ?? DateTime.Now).ToString("yyyy-MM-dd"),
+                    "%%" => "%",
+                    _ => m.Value
+                })
+            );
+
+            // Output is a directory
+            if (Directory.Exists(outputPath) || string.IsNullOrWhiteSpace(Path.GetExtension(outputPath)))
+            {
+                var fileName = GetDefaultOutputFileName(guild, channel, format, after, before);
+                return Path.Combine(outputPath, fileName);
+            }
+
+            // Output is a file
+            return outputPath;
+        }
+
+        public static string GetDefaultOutputFileName(
+            Guild guild,
+            Channel channel,
+            ExportFormat format,
+            Snowflake? after = null,
+            Snowflake? before = null)
+        {
+            var buffer = new StringBuilder();
+
+            // Guild and channel names
+            buffer.Append($"{guild.Name} - {channel.Category.Name} - {channel.Name} [{channel.Id}]");
+
+            // Date range
+            if (after is not null || before is not null)
+            {
+                buffer.Append(" (");
+
+                // Both 'after' and 'before' are set
+                if (after is not null && before is not null)
+                {
+                    buffer.Append($"{after?.ToDate():yyyy-MM-dd} to {before?.ToDate():yyyy-MM-dd}");
+                }
+                // Only 'after' is set
+                else if (after is not null)
+                {
+                    buffer.Append($"after {after?.ToDate():yyyy-MM-dd}");
+                }
+                // Only 'before' is set
+                else
+                {
+                    buffer.Append($"before {before?.ToDate():yyyy-MM-dd}");
+                }
+
+                buffer.Append(")");
+            }
+
+            // File extension
+            buffer.Append($".{format.GetFileExtension()}");
+
+            // Replace invalid chars
+            PathEx.EscapePath(buffer);
+
+            return buffer.ToString();
+        }
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/BinaryExpressionKind.cs

@@ -0,0 +1,8 @@
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal enum BinaryExpressionKind
+    {
+        Or,
+        And
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/BinaryExpressionMessageFilter.cs

@@ -0,0 +1,26 @@
+using System;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class BinaryExpressionMessageFilter : MessageFilter
+    {
+        private readonly MessageFilter _first;
+        private readonly MessageFilter _second;
+        private readonly BinaryExpressionKind _kind;
+
+        public BinaryExpressionMessageFilter(MessageFilter first, MessageFilter second, BinaryExpressionKind kind)
+        {
+            _first = first;
+            _second = second;
+            _kind = kind;
+        }
+
+        public override bool Filter(Message message) => _kind switch
+        {
+            BinaryExpressionKind.Or => _first.Filter(message) || _second.Filter(message),
+            BinaryExpressionKind.And => _first.Filter(message) && _second.Filter(message),
+            _ => throw new InvalidOperationException($"Unknown binary expression kind '{_kind}'.")
+        };
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/ContainsMessageFilter.cs

@@ -0,0 +1,18 @@
+using System.Text.RegularExpressions;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class ContainsMessageFilter : MessageFilter
+    {
+        private readonly string _text;
+
+        public ContainsMessageFilter(string text) => _text = text;
+
+        public override bool Filter(Message message) => Regex.IsMatch(
+            message.Content,
+            "\\b" + _text + "\\b",
+            RegexOptions.IgnoreCase | RegexOptions.CultureInvariant
+        );
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/FromMessageFilter.cs

@@ -0,0 +1,17 @@
+using System;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class FromMessageFilter : MessageFilter
+    {
+        private readonly string _value;
+
+        public FromMessageFilter(string value) => _value = value;
+
+        public override bool Filter(Message message) =>
+            string.Equals(_value, message.Author.Name, StringComparison.OrdinalIgnoreCase) ||
+            string.Equals(_value, message.Author.FullName, StringComparison.OrdinalIgnoreCase) ||
+            string.Equals(_value, message.Author.Id.ToString(), StringComparison.OrdinalIgnoreCase);
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/HasMessageFilter.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Linq;
+using System.Text.RegularExpressions;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class HasMessageFilter : MessageFilter
+    {
+        private readonly MessageContentMatchKind _kind;
+
+        public HasMessageFilter(MessageContentMatchKind kind) => _kind = kind;
+
+        public override bool Filter(Message message) => _kind switch
+        {
+            MessageContentMatchKind.Link => Regex.IsMatch(message.Content, "https?://\\S*[^\\.,:;\"\'\\s]"),
+            MessageContentMatchKind.Embed => message.Embeds.Any(),
+            MessageContentMatchKind.File => message.Attachments.Any(),
+            MessageContentMatchKind.Video => message.Attachments.Any(file => file.IsVideo),
+            MessageContentMatchKind.Image => message.Attachments.Any(file => file.IsImage),
+            MessageContentMatchKind.Sound => message.Attachments.Any(file => file.IsAudio),
+            _ => throw new InvalidOperationException($"Unknown message content match kind '{_kind}'.")
+        };
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/MentionsMessageFilter.cs

@@ -0,0 +1,19 @@
+using System;
+using System.Linq;
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class MentionsMessageFilter : MessageFilter
+    {
+        private readonly string _value;
+
+        public MentionsMessageFilter(string value) => _value = value;
+
+        public override bool Filter(Message message) => message.MentionedUsers.Any(user =>
+            string.Equals(_value, user.Name, StringComparison.OrdinalIgnoreCase) ||
+            string.Equals(_value, user.FullName, StringComparison.OrdinalIgnoreCase) ||
+            string.Equals(_value, user.Id.ToString(), StringComparison.OrdinalIgnoreCase)
+        );
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/MessageContentMatchKind.cs

@@ -0,0 +1,12 @@
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal enum MessageContentMatchKind
+    {
+        Link,
+        Embed,
+        File,
+        Video,
+        Image,
+        Sound
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/MessageFilter.cs

@@ -0,0 +1,18 @@
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Exporting.Filtering.Parsing;
+using Superpower;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    public abstract partial class MessageFilter
+    {
+        public abstract bool Filter(Message message);
+    }
+
+    public partial class MessageFilter
+    {
+        public static MessageFilter Null { get; } = new NullMessageFilter();
+
+        public static MessageFilter Parse(string value) => FilterGrammar.Filter.Parse(value);
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/NegatedMessageFilter.cs

@@ -0,0 +1,13 @@
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class NegatedMessageFilter : MessageFilter
+    {
+        private readonly MessageFilter _filter;
+
+        public NegatedMessageFilter(MessageFilter filter) => _filter = filter;
+
+        public override bool Filter(Message message) => !_filter.Filter(message);
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/NullMessageFilter.cs

@@ -0,0 +1,9 @@
+using DiscordChatExporter.Core.Discord.Data;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering
+{
+    internal class NullMessageFilter : MessageFilter
+    {
+        public override bool Filter(Message message) => true;
+    }
+}

DiscordChatExporter.Core/Exporting/Filtering/Parsing/FilterGrammar.cs

@@ -0,0 +1,106 @@
+using System.Linq;
+using DiscordChatExporter.Core.Utils.Extensions;
+using Superpower;
+using Superpower.Parsers;
+
+namespace DiscordChatExporter.Core.Exporting.Filtering.Parsing
+{
+    internal static class FilterGrammar
+    {
+        // Choice(a, b) looks cleaner than a.Or(b)
+        private static TextParser<T> Choice<T>(params TextParser<T>[] parsers) =>
+            parsers.Aggregate((current, next) => current.Or(next));
+
+        private static readonly TextParser<char> EscapedCharacter =
+            Character.EqualTo('\\').IgnoreThen(Character.AnyChar);
+
+        private static readonly TextParser<string> QuotedString =
+            from open in Character.In('"', '\'')
+            from value in Choice(EscapedCharacter, Character.Except(open)).Many().Text()
+            from close in Character.EqualTo(open)
+            select value;
+
+        private static readonly TextParser<char> FreeCharacter =
+            Character.Matching(c =>
+                    !char.IsWhiteSpace(c) &&
+                    // Avoid all special tokens used by the grammar
+                    c is not ('(' or ')' or '"' or '\'' or '-' or '|' or '&'),
+                "any character except whitespace or `(`, `)`, `\"`, `'`, `-`, `|`, `&`"
+            );
+
+        private static readonly TextParser<string> UnquotedString =
+            Choice(EscapedCharacter, FreeCharacter).AtLeastOnce().Text();
+
+        private static readonly TextParser<string> String =
+            Choice(QuotedString, UnquotedString).Named("text string");
+
+        private static readonly TextParser<MessageFilter> ContainsFilter =
+            String.Select(v => (MessageFilter) new ContainsMessageFilter(v));
+
+        private static readonly TextParser<MessageFilter> FromFilter = Span
+            .EqualToIgnoreCase("from:")
+            .IgnoreThen(String)
+            .Select(v => (MessageFilter) new FromMessageFilter(v))
+            .Named("from:<value>");
+
+        private static readonly TextParser<MessageFilter> MentionsFilter = Span
+            .EqualToIgnoreCase("mentions:")
+            .IgnoreThen(String)
+            .Select(v => (MessageFilter) new MentionsMessageFilter(v))
+            .Named("mentions:<value>");
+
+        private static readonly TextParser<MessageFilter> HasFilter = Span
+            .EqualToIgnoreCase("has:")
+            .IgnoreThen(Choice(
+                Span.EqualToIgnoreCase("link").IgnoreThen(Parse.Return(MessageContentMatchKind.Link)),
+                Span.EqualToIgnoreCase("embed").IgnoreThen(Parse.Return(MessageContentMatchKind.Embed)),
+                Span.EqualToIgnoreCase("video").IgnoreThen(Parse.Return(MessageContentMatchKind.Video)),
+                Span.EqualToIgnoreCase("image").IgnoreThen(Parse.Return(MessageContentMatchKind.Image)),
+                Span.EqualToIgnoreCase("sound").IgnoreThen(Parse.Return(MessageContentMatchKind.Sound))
+            ))
+            .Select(k => (MessageFilter) new HasMessageFilter(k))
+            .Named("has:<value>");
+
+        private static readonly TextParser<MessageFilter> NegatedFilter = Character
+            .EqualTo('-')
+            .IgnoreThen(Parse.Ref(() => StandaloneFilter))
+            .Select(f => (MessageFilter) new NegatedMessageFilter(f));
+
+        private static readonly TextParser<MessageFilter> GroupedFilter =
+            from open in Character.EqualTo('(')
+            from content in Parse.Ref(() => BinaryExpressionFilter).Token()
+            from close in Character.EqualTo(')')
+            select content;
+
+        private static readonly TextParser<MessageFilter> StandaloneFilter = Choice(
+            GroupedFilter,
+            FromFilter,
+            MentionsFilter,
+            HasFilter,
+            ContainsFilter
+        );
+
+        private static readonly TextParser<MessageFilter> UnaryExpressionFilter = Choice(
+            NegatedFilter,
+            StandaloneFilter
+        );
+
+        private static readonly TextParser<MessageFilter> BinaryExpressionFilter = Parse.Chain(
+            Choice(
+                // Explicit operator
+                Character.In('|', '&').Token().Try(),
+                // Implicit operator (resolves to 'and')
+                Character.WhiteSpace.AtLeastOnce().IgnoreThen(Parse.Return(' '))
+            ),
+            UnaryExpressionFilter,
+            (op, left, right) => op switch
+            {
+                '|' => new BinaryExpressionMessageFilter(left, right, BinaryExpressionKind.Or),
+                _ => new BinaryExpressionMessageFilter(left, right, BinaryExpressionKind.And)
+            }
+        );
+
+        public static readonly TextParser<MessageFilter> Filter =
+            BinaryExpressionFilter.Token().AtEnd();
+    }
+}

DiscordChatExporter.Core/Exporting/MediaDownloader.cs

@@ -0,0 +1,115 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.IO;
+using System.Net.Http;
+using System.Security.Cryptography;
+using System.Text;
+using System.Text.RegularExpressions;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Utils;
+using DiscordChatExporter.Core.Utils.Extensions;
+
+namespace DiscordChatExporter.Core.Exporting
+{
+    internal partial class MediaDownloader
+    {
+        private readonly HttpClient _httpClient;
+        private readonly string _workingDirPath;
+        private readonly bool _reuseMedia;
+
+        // URL -> Local file path
+        private readonly Dictionary<string, string> _pathCache = new(StringComparer.Ordinal);
+
+        public MediaDownloader(HttpClient httpClient, string workingDirPath, bool reuseMedia)
+        {
+            _httpClient = httpClient;
+            _workingDirPath = workingDirPath;
+            _reuseMedia = reuseMedia;
+        }
+
+        public MediaDownloader(string workingDirPath, bool reuseMedia)
+            : this(Http.Client, workingDirPath, reuseMedia) {}
+
+        public async ValueTask<string> DownloadAsync(string url)
+        {
+            if (_pathCache.TryGetValue(url, out var cachedFilePath))
+                return cachedFilePath;
+
+            var fileName = GetFileNameFromUrl(url);
+            var filePath = Path.Combine(_workingDirPath, fileName);
+
+            // Reuse existing files if we're allowed to
+            if (_reuseMedia && File.Exists(filePath))
+                return _pathCache[url] = filePath;
+
+            Directory.CreateDirectory(_workingDirPath);
+
+            // This retries on IOExceptions which is dangerous as we're also working with files
+            await Http.ExceptionPolicy.ExecuteAsync(async () =>
+            {
+                // Download the file
+                using var response = await _httpClient.GetAsync(url);
+                await using (var output = File.Create(filePath))
+                {
+                    await response.Content.CopyToAsync(output);
+                }
+
+                // Try to set the file date according to the last-modified header
+                try
+                {
+                    var lastModified = response.Content.Headers.TryGetValue("Last-Modified")?.Pipe(s =>
+                        DateTimeOffset.TryParse(s, CultureInfo.InvariantCulture, DateTimeStyles.None, out var date)
+                            ? date
+                            : (DateTimeOffset?) null
+                    );
+
+                    if (lastModified is not null)
+                    {
+                        File.SetCreationTimeUtc(filePath, lastModified.Value.UtcDateTime);
+                        File.SetLastWriteTimeUtc(filePath, lastModified.Value.UtcDateTime);
+                        File.SetLastAccessTimeUtc(filePath, lastModified.Value.UtcDateTime);
+                    }
+                }
+                catch
+                {
+                    // This can apparently fail for some reason.
+                    // https://github.com/Tyrrrz/DiscordChatExporter/issues/585
+                    // Updating file dates is not a critical task, so we'll just
+                    // ignore exceptions thrown here.
+                }
+            });
+
+            return _pathCache[url] = filePath;
+        }
+    }
+
+    internal partial class MediaDownloader
+    {
+        private static string GetUrlHash(string url)
+        {
+            using var hash = SHA256.Create();
+
+            var data = hash.ComputeHash(Encoding.UTF8.GetBytes(url));
+            return data.ToHex().Truncate(5); // 5 chars ought to be enough for anybody
+        }
+
+        private static string GetFileNameFromUrl(string url)
+        {
+            var urlHash = GetUrlHash(url);
+
+            // Try to extract file name from URL
+            var fileName = Regex.Match(url, @".+/([^?]*)").Groups[1].Value;
+
+            // If it's not there, just use the URL hash as the file name
+            if (string.IsNullOrWhiteSpace(fileName))
+                return urlHash;
+
+            // Otherwise, use the original file name but inject the hash in the middle
+            var fileNameWithoutExtension = Path.GetFileNameWithoutExtension(fileName);
+            var fileExtension = Path.GetExtension(fileName);
+
+            return PathEx.EscapePath(fileNameWithoutExtension.Truncate(42) + '-' + urlHash + fileExtension);
+        }
+    }
+}

DiscordChatExporter.Core/Exporting/MessageExporter.cs

@@ -0,0 +1,104 @@
+using System;
+using System.IO;
+using System.Threading.Tasks;
+using DiscordChatExporter.Core.Discord.Data;
+using DiscordChatExporter.Core.Exporting.Writers;
+
+namespace DiscordChatExporter.Core.Exporting
+{
+    internal partial class MessageExporter : IAsyncDisposable
+    {
+        private readonly ExportContext _context;
+
+        private int _partitionIndex;
+        private MessageWriter? _writer;
+
+        public MessageExporter(ExportContext context)
+        {
+            _context = context;
+        }
+
+        private async ValueTask ResetWriterAsync()
+        {
+            if (_writer is not null)
+            {
+                await _writer.WritePostambleAsync();
+                await _writer.DisposeAsync();
+                _writer = null;
+            }
+        }
+
+        private async ValueTask<MessageWriter> GetWriterAsync()
+        {
+            // Ensure partition limit has not been exceeded
+            if (_writer is not null &&
+                _context.Request.PartitionLimit.IsReached(_writer.MessagesWritten, _writer.BytesWritten))
+            {
+                await ResetWriterAsync();
+                _partitionIndex++;
+            }
+
+            // Writer is still valid - return
+            if (_writer is not null)
+                return _writer;
+
+            var filePath = GetPartitionFilePath(_context.Request.OutputBaseFilePath, _partitionIndex);
+
+            var dirPath = Path.GetDirectoryName(_context.Request.OutputBaseFilePath);
+            if (!string.IsNullOrWhiteSpace(dirPath))
+                Directory.CreateDirectory(dirPath);
+
+            var writer = CreateMessageWriter(filePath, _context.Request.Format, _context);
+            await writer.WritePreambleAsync();
+
+            return _writer = writer;
+        }
+
+        public async ValueTask ExportMessageAsync(Message message)
+        {
+            var writer = await GetWriterAsync();
+            await writer.WriteMessageAsync(message);
+        }
+
+        public async ValueTask DisposeAsync() => await ResetWriterAsync();
+    }
+
+    internal partial class MessageExporter
+    {
+        private static string GetPartitionFilePath(string baseFilePath, int partitionIndex)
+        {
+            // First partition - don't change file name
+            if (partitionIndex <= 0)
+                return baseFilePath;
+
+            // Inject partition index into file name
+            var fileNameWithoutExt = Path.GetFileNameWithoutExtension(baseFilePath);
+            var fileExt = Path.GetExtension(baseFilePath);
+            var fileName = $"{fileNameWithoutExt} [part {partitionIndex + 1}]{fileExt}";
+            var dirPath = Path.GetDirectoryName(baseFilePath);
+
+            return !string.IsNullOrWhiteSpace(dirPath)
+                ? Path.Combine(dirPath, fileName)
+                : fileName;
+        }
+
+        private static MessageWriter CreateMessageWriter(
+            string filePath,
+            ExportFormat format,
+            ExportContext context)
+        {
+            // Stream will be disposed by the underlying writer
+            var stream = File.Create(filePath);
+
+            return format switch
+            {
+                ExportFormat.PlainText => new PlainTextMessageWriter(stream, context),
+                ExportFormat.Csv => new CsvMessageWriter(stream, context),
+                ExportFormat.HtmlDark => new HtmlMessageWriter(stream, context, "Dark"),
+                ExportFormat.HtmlLight => new HtmlMessageWriter(stream, context, "Light"),
+                ExportFormat.Json => new JsonMessageWriter(stream, context),
+                _ => throw new ArgumentOutOfRangeException(nameof(format), $"Unknown export format '{format}'.")
+            };
+        }
+    }
+}

DiscordChatExporter.Core/Exporting/Partitioning/FileSizePartitionLimit.cs

@@ -0,0 +1,12 @@
+namespace DiscordChatExporter.Core.Exporting.Partitioning
+{
+    internal class FileSizePartitionLimit : PartitionLimit
+    {
+        private readonly long _limit;
+
+        public FileSizePartitionLimit(long limit) => _limit = limit;
+
+        public override bool IsReached(long messagesWritten, long bytesWritten) =>
+            bytesWritten >= _limit;
+    }
+}