/*
* LabeledMarker Class
*
* Copyright 2007 Mike Purvis (http://uwmike.com)
* 
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* 
*       http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This class extends the Maps API's standard GMarker class with the ability
* to support markers with textual labels. Please see articles here:
*
*       http://googlemapsbook.com/2007/01/22/extending-gmarker/
*       http://googlemapsbook.com/2007/03/06/clickable-labeledmarker/
*/

/* Constructor */
function LabeledMarker(latlng, options){
	this.latlng = latlng;
	this.labelText = options.labelText || "";
	this.labelClass = options.labelClass || "markerLabel";
	this.labelOffset = options.labelOffset || new google.maps.Size(0, 0);
	this.labelColor = options.labelColor || "#FFFFFF";
	
	this.clickable = options.clickable || true;
	
	if (options.draggable) {
		// This version of LabeledMarker doesn't support dragging.
		options.draggable = false;
	}
	
	google.maps.Marker.apply(this, arguments);
}


/* It's a limitation of JavaScript inheritance that we can't conveniently
   extend GMarker without having to run its constructor. In order for the
   constructor to run, it requires some dummy GLatLng. */
function  initLabeledMarker(){
	LabeledMarker.prototype = new google.maps.Marker(new google.maps.LatLng(0, 0));
		
		// Creates the text div that goes over the marker.
	
	LabeledMarker.prototype.initialize = function(map) {
		// Do the GMarker constructor first.
		GMarker.prototype.initialize.apply(this, arguments);

		var div = document.createElement("div");
		div.className = this.labelClass;
		div.innerHTML = this.labelText;
		div.style.position = "absolute";
		div.style.backgroundColor = this.labelColor;
		map.getPane(G_MAP_MARKER_PANE).appendChild(div);

		if (this.clickable) {
			// Pass through events fired on the text div to the marker.
			var eventPassthrus = ['click', 'dblclick', 'mousedown', 'mouseup', 'mouseover', 'mouseout'];
			for(var i = 0; i < eventPassthrus.length; i++) {
				var name = eventPassthrus[i];
				google.maps.Event.addDomListener(div, name, newEventPassthru(this, name));
			}

			// Mouseover behaviour for the cursor.
			div.style.cursor = "pointer";
		}
			
			this.map = map;
			this.div = div;
	}

	// Redraw the rectangle based on the current projection and zoom level
	LabeledMarker.prototype.redraw = function(force) {
		google.maps.Marker.prototype.redraw.apply(this, arguments);
		
		// We only need to do anything if the coordinate system has changed
		if (!force) return;
		
		// Calculate the DIV coordinates of two opposite corners of our bounds to
		// get the size and position of our rectangle
		var p = this.map.fromLatLngToDivPixel(this.getLatLng());
		var z = google.maps.Overlay.getZIndex(this.getLatLng().lat());
		
		// Now position our DIV based on the DIV coordinates of our bounds
		//this.div.style.left = (p.x + this.labelOffset.width) + "px";
		this.div.style.top = (p.y + this.labelOffset.height) + "px";
		this.div.style.zIndex = z + 1; // in front of the marker
		this.div.setAttribute("class", "marker");
		this.div.setAttribute("className", "marker"); //for IE
		
		var centOffs = parseInt(this.div.offsetWidth) / 2;
		this.div.style.left = (p.x + this.labelOffset.width - centOffs) + "px";
	}

	// Remove the main DIV from the map pane, destroy event handlers
	LabeledMarker.prototype.remove = function() {
		google.maps.Event.clearInstanceListeners(this.div);
		this.div.parentNode.removeChild(this.div);
		this.div = null;
		google.maps.Marker.prototype.remove.apply(this, arguments);
	}
}

function newEventPassthru(obj, event) {
	return function() { 
		google.maps.Event.trigger(obj, event);
	};
}