import { Request, Response, NextFunction } from "express";
import { z } from "zod";
import { db } from "@server/db";
import { userResources, userPolicies, resources } from "@server/db";
import response from "@server/lib/response";
import HttpCode from "@server/types/HttpCode";
import createHttpError from "http-errors";
import logger from "@server/logger";
import { fromError } from "zod-validation-error";
import { eq } from "drizzle-orm";
import { OpenAPITags, registry } from "@server/openApi";

const setUserResourcesBodySchema = z.strictObject({
    userIds: z.array(z.string())
});

const setUserResourcesParamsSchema = z.strictObject({
    resourceId: z.coerce.number().int().positive()
});

registry.registerPath({
    method: "post",
    path: "/resource/{resourceId}/users",
    description:
        "Set users for a resource. This will replace all existing users.",
    tags: [OpenAPITags.PublicResource, OpenAPITags.User],
    request: {
        params: setUserResourcesParamsSchema,
        body: {
            content: {
                "application/json": {
                    schema: setUserResourcesBodySchema
                }
            }
        }
    },
    responses: {
        200: {
            description: "Successful response",
            content: {
                "application/json": {
                    schema: z.object({
                        data: z.unknown().nullable(),
                        success: z.boolean(),
                        error: z.boolean(),
                        message: z.string(),
                        status: z.number()
                    })
                }
            }
        }
    }
});

export async function setResourceUsers(
    req: Request,
    res: Response,
    next: NextFunction
): Promise<any> {
    try {
        const parsedBody = setUserResourcesBodySchema.safeParse(req.body);
        if (!parsedBody.success) {
            return next(
                createHttpError(
                    HttpCode.BAD_REQUEST,
                    fromError(parsedBody.error).toString()
                )
            );
        }

        const { userIds } = parsedBody.data;

        const parsedParams = setUserResourcesParamsSchema.safeParse(req.params);
        if (!parsedParams.success) {
            return next(
                createHttpError(
                    HttpCode.BAD_REQUEST,
                    fromError(parsedParams.error).toString()
                )
            );
        }

        const { resourceId } = parsedParams.data;

        const [resource] = await db
            .select()
            .from(resources)
            .where(eq(resources.resourceId, resourceId))
            .limit(1);

        if (!resource) {
            return next(
                createHttpError(HttpCode.NOT_FOUND, "Resource not found")
            );
        }

        const isInlinePolicy =
            resource.resourcePolicyId === null &&
            resource.defaultResourcePolicyId !== null;

        await db.transaction(async (trx) => {
            if (isInlinePolicy) {
                const policyId = resource.defaultResourcePolicyId!;
                await trx
                    .delete(userPolicies)
                    .where(eq(userPolicies.resourcePolicyId, policyId));

                await Promise.all(
                    userIds.map((userId) =>
                        trx
                            .insert(userPolicies)
                            .values({ userId, resourcePolicyId: policyId })
                            .returning()
                    )
                );
            } else {
                await trx
                    .delete(userResources)
                    .where(eq(userResources.resourceId, resourceId));

                await Promise.all(
                    userIds.map((userId) =>
                        trx
                            .insert(userResources)
                            .values({ userId, resourceId })
                            .returning()
                    )
                );
            }

            return response(res, {
                data: {},
                success: true,
                error: false,
                message: "Users set for resource successfully",
                status: HttpCode.CREATED
            });
        });
    } catch (error) {
        logger.error(error);
        return next(
            createHttpError(HttpCode.INTERNAL_SERVER_ERROR, "An error occurred")
        );
    }
}