/*
	Spacebar: A FOSS re-implementation and extension of the Discord.com backend.
	Copyright (C) 2023 Spacebar and Spacebar 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 { route } from "@spacebar/api";
import { Channel, ChannelRecipientAddEvent, DiscordApiErrors, DmChannelDTO, emitEvent, Recipient, User } from "@spacebar/util";
import { Request, Response, Router } from "express";
import { ChannelType, PublicUserProjection } from "@spacebar/schemas";

const router: Router = Router({ mergeParams: true });

router.put(
    "/:user_id",
    route({
        responses: {
            201: {},
            404: {},
        },
    }),
    async (req: Request, res: Response) => {
        const { channel_id, user_id } = req.params as { [key: string]: string };
        const channel = await Channel.findOneOrFail({
            where: { id: channel_id },
            relations: { recipients: true },
        });

        if (channel.type !== ChannelType.GROUP_DM) {
            const recipients = [...new Set([...(channel.recipients?.map((r) => r.user_id) || []), user_id])];

            const new_channel = await Channel.createDMChannel(recipients, req.user_id);
            return res.status(201).json(new_channel);
        } else {
            if (channel.recipients?.map((r) => r.user_id).includes(user_id)) {
                throw DiscordApiErrors.INVALID_RECIPIENT; //TODO is this the right error?
            }

            channel.recipients?.push(Recipient.create({ channel_id: channel_id, user_id: user_id }));
            await channel.save();

            await emitEvent({
                event: "CHANNEL_CREATE",
                data: await DmChannelDTO.from(channel, [user_id]),
                user_id: user_id,
            });

            await emitEvent({
                event: "CHANNEL_RECIPIENT_ADD",
                data: {
                    channel_id: channel_id,
                    user: (
                        await User.findOneOrFail({
                            where: { id: user_id },
                            select: PublicUserProjection,
                        })
                    ).toPublicUser(),
                },
                channel_id: channel_id,
            } satisfies ChannelRecipientAddEvent);
            return res.sendStatus(204);
        }
    },
);

router.delete(
    "/:user_id",
    route({
        responses: {
            204: {},
            404: {},
        },
    }),
    async (req: Request, res: Response) => {
        const { channel_id, user_id } = req.params as { [key: string]: string };
        const channel = await Channel.findOneOrFail({
            where: { id: channel_id },
            relations: { recipients: true },
        });
        if (!(channel.type === ChannelType.GROUP_DM && (channel.owner_id === req.user_id || user_id === req.user_id))) throw DiscordApiErrors.MISSING_PERMISSIONS;

        if (!channel.recipients?.map((r) => r.user_id).includes(user_id)) {
            throw DiscordApiErrors.INVALID_RECIPIENT; //TODO is this the right error?
        }

        await Channel.removeRecipientFromChannel(channel, user_id);

        return res.sendStatus(204);
    },
);

export default router;
