/****************************************************************************************************************
 * CLASS DB:          contains all data about routes and linked pois                                            *
 *                                                                                                              *
 *   Events:          body.databaseLoaded(database:DB)                                                          *
 *                                                                                                              *
 *  Returns:          Array of routes in format                                                                 *
 *                    Object{                                                                                   *
 *                      id:Number,                                                                              *
 *                      name:String,                                                                            *
 *                      image:String,                                                                           *
 *                      languages:Array(String),                                                                *
 *                      pois:Array(Object{                                                                      *
 *                        lat:Number,                                                                           *
 *                        lon:Number,                                                                           *
 *                        desc:String,                                                                          *
 *                        range:Number,                                                                         *
 *                        audio:Number                                                                          *
 *                      }                                                                                       *
 *                    }                                                                                         *
 ****************************************************************************************************************/

function DB() {
	var that = this;
	this._routes = []; // format: {id:0, name:'', image:'', languages:[], pois:[{lat:0, lon:0, desc:'', range:0, audio:0}]}
	this._completeTracks = Array();
	
	this._init = function() {
		$('#database-loading').slideDown({duration: 500});
		console.debug('loading database');
		$.getJSON('database.php', {'get':'routes'}, function(data) {
			console.debug('database: routes received');
			data.forEach(function(track) {
				//console.debug(id, track);
				that._completeTracks[track.id] = false;
				$.getJSON('database.php', {'get':'pois','id':track.id}, function(pois) {
					console.debug(track.name, pois);
//					console.debug('database: '+pois.length+' pois for '+track.name+' received');
					track.pois = pois;
					that._routes[track.id] = (track);
					that._completeTracks[track.id] = true;
					
					//console.debug('track done:', track);
					
					if (that._completeTracks.reduce(function(prev, curr) { return (prev && curr); }, true)) {			//tracks complete ?
						$('#database-loading').slideUp({duration: 500});
						console.debug('database loaded');
						$('body').trigger('databaseLoaded', that);
					}
				});
			});
		});
	}
	
	this._init();
	
	return this._routes;
}