const models = require('../models');
import * as api from '../../client/src/api';
import { EndpointError, EndpointHandler, catchUnhandledErrors } from './types';
const { Op } = require("sequelize");

export const ModifySongEndpointHandler: EndpointHandler = async (req: any, res: any) => {
    if (!api.checkModifySongRequest(req)) {
        const e: EndpointError = {
            internalMessage: 'Invalid ModifySong request: ' + JSON.stringify(req.body),
            httpStatus: 400
        };
        throw e;
    }
    const reqObject: api.ModifySongRequest = req.body;

    // Start retrieving the artist instances to link the song to.
    var artistInstancesPromise = reqObject.artistIds && models.Artist.findAll({
        where: {
            id: {
                [Op.in]: reqObject.artistIds
            }
        }
    });

    // Start retrieving the album instances to link the song to.
    var albumInstancesPromise = reqObject.albumIds && models.Album.findAll({
        where: {
            id: {
                [Op.in]: reqObject.albumIds
            }
        }
    });

    // Start retrieving the tag instances to link the song to.
    var tagInstancesPromise = reqObject.tagIds && models.Tag.findAll({
        where: {
            id: {
                [Op.in]: reqObject.tagIds
            }
        }
    });

    // Start retrieving the song to modify.
    var songInstancePromise = models.Song.findAll({
        where: {
            id: req.params.id
        }
    });

    // Upon finish retrieving artists and albums, modify the song.
    await Promise.all([artistInstancesPromise, albumInstancesPromise, tagInstancesPromise, songInstancePromise])
        .then(async (values: any) => {
            var [artists, albums, tags, song] = values;
            if (reqObject.artistIds) { song.setArtists(artists) };
            if (reqObject.albumIds) { song.setAlbums(albums) };
            if (reqObject.tagIds) { song.setTags(tags) };
            if (reqObject.title) { song.setTitle(reqObject.title) };
            if (reqObject.storeLinks) { song.setStoreIds(reqObject.storeLinks) };
            await song.save();
        })
        .then(() => {
            res.status(200).send({});
        })
        .catch(catchUnhandledErrors);
}