/*
 *   Map - Easy to use OpenLayers map object
 * 
 *	by Smári McCarthy & Olle Jonsson
 *
 *	Freely distributable under the terms of the GNU General Public License v3.0
 */

function Map() {
	var map;
	var layers = {};
	var icon;
	
	return {
        
		getMap: function() {
			return map;
		},
	
		init: function(element, mlat, mlon, mzoom) {

			// Where to focus at first
			var lat=23;
			var lon=0;
			var zoom=2;
			if (mlat != undefined) {
				var lat = mlat;
			}
			if (mlon != undefined) {
				var lon = mlon;
			}
			if (mzoom != undefined) {
				var zoom = mzoom;
			}

			// Create the map itself...
			map = new OpenLayers.Map(element, {
				controls:[
					new OpenLayers.Control.Navigation(),
					new OpenLayers.Control.PanZoomBar(),
					new OpenLayers.Control.MousePosition(),
					new OpenLayers.Control.LayerSwitcher(),
				],
				maxExtent: new OpenLayers.Bounds(-20037508.34,-20037508.34,20037508.34,20037508.34),
				maxResolution: 156543.0399,
				numZoomLevels: 17,
				units: 'm',
				projection: new OpenLayers.Projection("EPSG:900913"),
				displayProjection: new OpenLayers.Projection("EPSG:4326"),
				// I don't know why we're registering all these event listeners? Can't we do this a smarter way?
				eventListeners: {
					"moveend": this.onMapEvent,
					"zoomend": this.onMapEvent,
					"changelayer": this.onMapLayerChanged,
					"changebaselayer": this.onMapBaseLayerChanged,
				}
			} );
 
			// FIXME: We want to be able to control arbitrary layers here. for more general purpose mapping
 
			// The TilesAtHome layer...
			layers["mapnik"] = new OpenLayers.Layer.OSM.Mapnik("Mapnik");
			layers["tilesathome"] = new OpenLayers.Layer.OSM.Osmarender("Tiles@Home");
			map.addLayers([layers["tilesathome"], layers["mapnik"]]);
			
			// The Sites layer...
			layers["sites"] = new OpenLayers.Layer.Markers("Sites");
			map.addLayer(layers["sites"]);
			
			layers["sites"].events.on({
				'featureselected': this.onFeatureSelect,
				'featureunselected': this.onFeatureUnselect
			});
	 
			// Zoom to the initial center
			if( ! map.getCenter() ){
				var lonLat = new OpenLayers.LonLat(lon, lat).transform(map.displayProjection, map.projection);
				map.setCenter (lonLat, zoom);
			}
			
			// Return the map object for handy direct manipulation.
			return map;
		},
		
		onMapEvent: function(evt) {
		
		},
		
		onMapLayerChanged: function(evt) {
		
		},
		
		onMapBaseLayerChanged: function(evt) {
		
		},
        
		onFeatureSelect: function(evt) {
			var feature = evt.feature;
			var popup = new OpenLayers.Popup.FramedCloud("featurePopup",
				feature.geometry.getBounds().getCenterLonLat(),
				new OpenLayers.Size(100,100),
				'Foo!',
				null, true, this.onPopupClose);
			feature.popup = popup;
			popup.feature = feature;
			map.addPopup(popup);
		},
		
		onFeatureUnselect: function (evt) {
			var feature = evt.feature;
			if (feature.popup) {
				popup.feature = null;
				map.removePopup(feature.popup);
				feature.popup.destroy();
				feature.popup = null;
			}
		},
        
		createMarker: function(lat, lon, name, locname, website) {
			// new OpenLayers.Marker(lonLat,icon),
			// Create a handy marker icon... (FIXME: this should be elsewhere)
			var size = new OpenLayers.Size(21,25);
			var offset = new OpenLayers.Pixel(-(size.w/2), -size.h);
			var icon = new OpenLayers.Icon('http://www.openstreetmap.org/openlayers/img/marker.png',size,offset);
			var point = new OpenLayers.LonLat(lon, lat).transform(map.displayProjection, map.projection);
			var marker = new OpenLayers.Marker(point, icon);
			// var m = marker.attributes;
			// m.lat = lat;
			// m.lon = lon;
			// m.name = name;
			// m.locname = locname;
			// m.website = website;
			return marker;
		},
		
		addMarker: function(layer, marker) {
			if (layers[layer] != undefined) {
				layers[layer].addMarker(marker);
			}
		},
		
		// FIXME: This needs generalizing
		quickMarker: function(layer, lat, lon, name, locname, website, icon) {
			this.addMarker(layer, this.createMarker(lat, lon, name, locname, website));
		},
	
		zoomLocation: function(lat, lon, zoom) {
			map.setCenter(new OpenLayers.LonLat(lon, lat).transform(map.displayProjection, map.projection), zoom);  
		},
        
		onPopupClose: function(evt) {
			// 'this' is the popup.
			selectControl.unselect(this.feature);
		}
	};
}