import * as api from '../../client/src/api';
import { EndpointError, EndpointHandler, catchUnhandledErrors } from './types';
import Knex from 'knex';
import asJson from '../lib/asJson';

export const AlbumDetailsEndpointHandler: EndpointHandler = async (req: any, res: any, knex: Knex) => {
    if (!api.checkAlbumDetailsRequest(req)) {
        const e: EndpointError = {
            internalMessage: 'Invalid AlbumDetails request: ' + JSON.stringify(req.body),
            httpStatus: 400
        };
        throw e;
    }

    const { id: userId } = req.user;

    try {
        // Start transfers for songs, tags and artists.
        // Also request the album itself.
        const tagIdsPromise = knex.select('tagId')
            .from('albums_tags')
            .where({ 'albumId': req.params.id })
            .then((tags: any) => {
                return tags.map((tag: any) => tag['tagId'])
            });
        const songIdsPromise = knex.select('songId')
            .from('songs_albums')
            .where({ 'albumId': req.params.id })
            .then((songs: any) => {
                return songs.map((song: any) => song['songId'])
            });
        const artistIdsPromise = knex.select('artistId')
            .from('artists_albums')
            .where({ 'albumId': req.params.id })
            .then((artists: any) => {
                return artists.map((artist: any) => artist['artistId'])
            });
        const albumPromise = knex.select('name', 'storeLinks')
            .from('albums')
            .where({ 'user': userId })
            .where({ id: req.params.id })
            .then((albums: any) => albums[0]);

        // Wait for the requests to finish.
        const [album, tags, songs, artists] =
            await Promise.all([albumPromise, tagIdsPromise, songIdsPromise, artistIdsPromise]);

        // Respond to the request.
        const response: api.AlbumDetailsResponse = {
            name: album['name'],
            artistIds: artists,
            tagIds: tags,
            songIds: songs,
            storeLinks: asJson(album['storeLinks']),
        };

        await res.send(response);
    } catch (e) {
        catchUnhandledErrors(e);
    }
}