/*
	Fosscord: A FOSS re-implementation and extension of the Discord.com backend.
	Copyright (C) 2023 Fosscord and Fosscord Contributors
	
	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published
	by the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.
	
	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.
	
	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

import { Router, Request, Response } from "express";
import { route } from "@fosscord/api";
import {
	ApiError,
	Application,
	ApplicationAuthorizeSchema,
	getPermission,
	DiscordApiErrors,
	Member,
	Permissions,
	User,
} from "@fosscord/util";
const router = Router();

// TODO: scopes, other oauth types

router.get("/", route({}), async (req: Request, res: Response) => {
	// const { client_id, scope, response_type, redirect_url } = req.query;
	const { client_id } = req.query;

	const app = await Application.findOne({
		where: {
			id: client_id as string,
		},
		relations: ["bot"],
	});

	// TODO: use DiscordApiErrors
	// findOneOrFail throws code 404
	if (!app) throw DiscordApiErrors.UNKNOWN_APPLICATION;
	if (!app.bot) throw DiscordApiErrors.OAUTH2_APPLICATION_BOT_ABSENT;

	const bot = app.bot;
	delete app.bot;

	const user = await User.findOneOrFail({
		where: {
			id: req.user_id,
			bot: false,
		},
		select: ["id", "username", "avatar", "discriminator", "public_flags"],
	});

	const guilds = await Member.find({
		where: {
			user: {
				id: req.user_id,
			},
		},
		relations: ["guild", "roles"],
		// eslint-disable-next-line @typescript-eslint/ban-ts-comment
		//@ts-ignore
		// prettier-ignore
		select: ["guild.id", "guild.name", "guild.icon", "guild.mfa_level", "guild.owner_id", "roles.id"],
	});

	const guildsWithPermissions = guilds.map((x) => {
		const perms =
			x.guild.owner_id === user.id
				? new Permissions(Permissions.FLAGS.ADMINISTRATOR)
				: Permissions.finalPermission({
						user: {
							id: user.id,
							roles: x.roles?.map((x) => x.id) || [],
						},
						guild: {
							roles: x?.roles || [],
						},
				  });

		return {
			id: x.guild.id,
			name: x.guild.name,
			icon: x.guild.icon,
			mfa_level: x.guild.mfa_level,
			permissions: perms.bitfield.toString(),
		};
	});

	return res.json({
		guilds: guildsWithPermissions,
		user: {
			id: user.id,
			username: user.username,
			avatar: user.avatar,
			avatar_decoration: null, // TODO
			discriminator: user.discriminator,
			public_flags: user.public_flags,
		},
		application: {
			id: app.id,
			name: app.name,
			icon: app.icon,
			description: app.description,
			summary: app.summary,
			type: app.type,
			hook: app.hook,
			guild_id: null, // TODO support guilds
			bot_public: app.bot_public,
			bot_require_code_grant: app.bot_require_code_grant,
			verify_key: app.verify_key,
			flags: app.flags,
		},
		bot: {
			id: bot.id,
			username: bot.username,
			avatar: bot.avatar,
			avatar_decoration: null, // TODO
			discriminator: bot.discriminator,
			public_flags: bot.public_flags,
			bot: true,
			approximated_guild_count: 0, // TODO
		},
		authorized: false,
	});
});

router.post(
	"/",
	route({ body: "ApplicationAuthorizeSchema" }),
	async (req: Request, res: Response) => {
		const body = req.body as ApplicationAuthorizeSchema;
		// const { client_id, scope, response_type, redirect_url } = req.query;
		const { client_id } = req.query;

		// TODO: captcha verification
		// TODO: MFA verification

		const perms = await getPermission(
			req.user_id,
			body.guild_id,
			undefined,
			{ member_relations: ["user"] },
		);
		// getPermission cache won't exist if we're owner
		if (
			Object.keys(perms.cache || {}).length > 0 &&
			perms.cache.member?.user.bot
		)
			throw DiscordApiErrors.UNAUTHORIZED;
		perms.hasThrow("MANAGE_GUILD");

		const app = await Application.findOne({
			where: {
				id: client_id as string,
			},
			relations: ["bot"],
		});

		// TODO: use DiscordApiErrors
		// findOneOrFail throws code 404
		if (!app) throw new ApiError("Unknown Application", 10002, 404);
		if (!app.bot)
			throw new ApiError(
				"OAuth2 application does not have a bot",
				50010,
				400,
			);

		await Member.addToGuild(app.id, body.guild_id);

		return res.json({
			location: "/oauth2/authorized", // redirect URL
		});
	},
);

export default router;