Darep/Beatstream

//= require lib/api
//= require lib/mediator
//= require lib/mediator_events

var App = window.App || {};

(function (undefined) {

    var scrobble_time = 240,
        song_scrobbled = false,
        song_scrobbling = false;

    var lastfm = {
        song: undefined,

        newSong: function (song) {
            if (!song) {
                return;
            }

            this.song = song;

            scrobble_time = Math.floor(song.length/2, 10);

            // don't scrobble songs that are under 30 secs (last.fm rule)
            if (scrobble_time <= 15) {
                song_scrobbled = true;
                return;
            }

            // Always scrobble at 4 min mark if song is e.g. 60 minutes long
            if (scrobble_time > 240) {
                scrobble_time = 240;
            }

            App.API.updateNowPlaying(song.artist, song.title).then(function () {
                song_scrobbled = false;
                song_scrobbling = false;
                App.Mediator.subscribe(MediatorEvents.AUDIO_TIME, lastfm.checkScrobble);
            }, function () {
                song_scrobbled = false;
                song_scrobbling = false;
            });
        },

        checkScrobble: function (elaps) {
            if (song_scrobbling || song_scrobbled || elaps < scrobble_time || !lastfm.song) {
                return;
            }

            lastfm.scrobble().bind(lastfm);
        },

        scrobble: function () {
            if (song_scrobbling) {
                return;
            }

            song_scrobbling = true;

            App.API.scrobble(this.song.artist, this.song.title).then(function () {
                song_scrobbled = true;
                song_scrobbling = false;
                App.Mediator.unsubscribe(MediatorEvents.AUDIO_TIME, lastfm.checkScrobble);
            }, function () {
                song_scrobbled = true;
                song_scrobbling = false;
                App.Mediator.unsubscribe(MediatorEvents.AUDIO_TIME, lastfm.checkScrobble);
            });
        }
    };

    App.lastfm = lastfm;

})();