// Clusterer.js - marker clustering routines for Google Maps apps
//
// Using these routines is very easy.
//
// 1) Load the routines into your code:
//
//        <script src="http://www.acme.com/javascript/Clusterer.js" type="text/javascript"></script>
//
// 2) Create a Clusterer object, passing it your map object:
//
//        var clusterer = new Clusterer( map );
//
// 3) Wherever you now do map.addOverlay( marker ), instead call
//    clusterer.AddMarker( marker, title ).  The title is just a
//    short descriptive string to use in the cluster info-boxes.
//
// 4) If you are doing any map.removeOverlay( marker ) calls, change those
//    to clusterer.RemoveMarker( marker ).
//
// That's it!  Everything else happens automatically.
//
//
// The current version of this code is always available at:
// http://www.acme.com/javascript/
//
//
// Copyright © 2005,2006 by Jef Poskanzer <jef@mail.acme.com>.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE.
//
// For commentary on this license please see http://www.acme.com/license.html


// Constructor.
Clusterer = function ( map )
    {
    this.map = map;
    this.markers = [];
    this.clusters = [];
    this.timeout = null;
    this.currentZoomLevel = map.getZoom();

    this.maxVisibleMarkers = Clusterer.defaultMaxVisibleMarkers;
    this.gridSize = Clusterer.defaultGridSize;
    this.minMarkersPerCluster = Clusterer.defaultMinMarkersPerCluster;
    this.maxLinesPerInfoBox = Clusterer.defaultMaxLinesPerInfoBox;
    this.icon = Clusterer.defaultIcon;

    GEvent.addListener( map, 'zoomend', Clusterer.MakeCaller( Clusterer.Display, this ) );
    GEvent.addListener( map, 'moveend', Clusterer.MakeCaller( Clusterer.Display, this ) );
    GEvent.addListener( map, 'infowindowclose', Clusterer.MakeCaller( Clusterer.PopDown, this ) );
    };


Clusterer.defaultMaxVisibleMarkers = 150;
Clusterer.defaultGridSize = 5;
Clusterer.defaultMinMarkersPerCluster = 5;
Clusterer.defaultMaxLinesPerInfoBox = 10;

Clusterer.defaultIcon = new GIcon();
Clusterer.defaultIcon.image 	= 'http://www.acme.com/resources/images/markers/blue_large.PNG';
Clusterer.defaultIcon.shadow 	= 'http://www.acme.com/resources/images/markers/shadow_large.PNG';
Clusterer.defaultIcon.iconSize 		= new GSize( 30, 51 );
Clusterer.defaultIcon.shadowSize 	= new GSize( 56, 51 );
Clusterer.defaultIcon.iconAnchor 	= new GPoint( 13, 34 );
Clusterer.defaultIcon.infoWindowAnchor = new GPoint( 13, 3 );
Clusterer.defaultIcon.infoShadowAnchor = new GPoint( 27, 37 );


// Call this to change the cluster icon.
Clusterer.prototype.SetIcon = function ( icon ){
    this.icon = icon;
};


// Changes the maximum number of visible markers before clustering kicks in.
Clusterer.prototype.SetMaxVisibleMarkers = function ( n ){
    this.maxVisibleMarkers = n;
};


// Sets the minumum number of markers for a cluster.
Clusterer.prototype.SetMinMarkersPerCluster = function ( n ) {
	this.minMarkersPerCluster = n;
};


// Sets the maximum number of lines in an info box.
Clusterer.prototype.SetMaxLinesPerInfoBox = function ( n ){
	this.maxLinesPerInfoBox = n;
};


// Call this to add a marker.
Clusterer.prototype.AddMarker = function ( marker, title ){
	if ( marker.setMap != null )
	marker.setMap( this.map );
	marker.title = title;
	marker.onMap = false;
	this.markers.push( marker );
	this.DisplayLater();
};


// Call this to remove a marker.
Clusterer.prototype.RemoveMarker = function ( marker ){
    for ( var i = 0; i < this.markers.length; ++i )
	if ( this.markers[i] == marker )
	    {
	    if ( marker.onMap )
		this.map.removeOverlay( marker );
	    for ( var j = 0; j < this.clusters.length; ++j )
		{
		var cluster = this.clusters[j];
		if ( cluster != null )
		    {
		    for ( var k = 0; k < cluster.markers.length; ++k )
			if ( cluster.markers[k] == marker )
			    {
			    cluster.markers[k] = null;
			    --cluster.markerCount;
			    break;
			    }
		    if ( cluster.markerCount == 0 )
			{
			this.ClearCluster( cluster );
			this.clusters[j] = null;
			}
		    else if ( cluster == this.poppedUpCluster )
			Clusterer.RePop( this );
		    }
		}
	    this.markers[i] = null;
	    break;
	    }
    this.DisplayLater();
};


Clusterer.prototype.DisplayLater = function () {
	if ( this.timeout != null )
	clearTimeout( this.timeout );
	this.timeout = setTimeout( Clusterer.MakeCaller( Clusterer.Display, this ), 50 );
};


Clusterer.Display = function ( clusterer ) {
	var i, j, marker, cluster;
	
	clearTimeout( clusterer.timeout );
	
	var newZoomLevel = clusterer.map.getZoom();
	if ( newZoomLevel != clusterer.currentZoomLevel ) {
		// When the zoom level changes, we have to remove all the clusters.
		for ( i = 0; i < clusterer.clusters.length; ++i )
			if ( clusterer.clusters[i] != null ) {
				clusterer.ClearCluster( clusterer.clusters[i] );
				clusterer.clusters[i] = null;
			}
		clusterer.clusters.length = 0;
		clusterer.currentZoomLevel = newZoomLevel;
	}
	
	// Get the current bounds of the visible area.
	var bounds = clusterer.map.getBounds();
	
	// Expand the bounds a little, so things look smoother when scrolling
	// by small amounts.
	var sw = bounds.getSouthWest();
	var ne = bounds.getNorthEast();
	var dx = ne.lng() - sw.lng();
	var dy = ne.lat() - sw.lat();
	if ( dx < 300 && dy < 150 ) {
		dx *= 0.10;
		dy *= 0.10;
		bounds = new GLatLngBounds(
			new GLatLng( sw.lat() - dy, sw.lng() - dx ),
			new GLatLng( ne.lat() + dy, ne.lng() + dx ) 
		);
	}
	
	// Partition the markers into visible and non-visible lists.
	var visibleMarkers 		= []; // Count of all markers
	var nonvisibleMarkers 	= [];
	for ( i = 0; i < clusterer.markers.length; ++i ) {
		marker = clusterer.markers[i];
		if ( marker != null )
			if ( bounds.contains( marker.getPoint() ) )
				visibleMarkers.push( marker );
			else
				nonvisibleMarkers.push( marker );
	}
	
	// Take down the non-visible markers.
	for ( i = 0; i < nonvisibleMarkers.length; ++i ){
		marker = nonvisibleMarkers[i];
		if ( marker.onMap ){
			clusterer.map.removeOverlay( marker );
			marker.onMap = false;
		}
	}
	
	// Take down the non-visible clusters.
	for ( i = 0; i < clusterer.clusters.length; ++i ) {
	cluster = clusterer.clusters[i];
	if ( cluster != null && ! bounds.contains( cluster.marker.getPoint() ) && cluster.onMap ) {
		clusterer.map.removeOverlay( cluster.marker );
		cluster.onMap = false;
		}
	}
	
	// Clustering!  This is some complicated stuff.  We have three goals
	// here.  One, limit the number of markers & clusters displayed, so the
	// maps code doesn't slow to a crawl.  Two, when possible keep existing
	// clusters instead of replacing them with new ones, so that the app pans
	// better.  And three, of course, be CPU and memory efficient.
	if ( visibleMarkers.length > clusterer.maxVisibleMarkers ){
		// Add to the list of clusters by splitting up the current bounds
		// into a grid.
		var latRange = bounds.getNorthEast().lat() - bounds.getSouthWest().lat();
		var latInc = latRange / clusterer.gridSize;
		var lngInc = latInc / Math.cos( ( bounds.getNorthEast().lat() + bounds.getSouthWest().lat() ) / 2.0 * Math.PI / 180.0 );
		for ( var lat = bounds.getSouthWest().lat(); lat <= bounds.getNorthEast().lat(); lat += latInc )
			for ( var lng = bounds.getSouthWest().lng(); lng <= bounds.getNorthEast().lng(); lng += lngInc ) {
				cluster = new Object();
				cluster.clusterer = clusterer;
				cluster.bounds = new GLatLngBounds( new GLatLng( lat, lng ), new GLatLng( lat + latInc, lng + lngInc ) );
				cluster.markers = [];
				cluster.markerCount = 0;
				cluster.onMap = false;
				cluster.marker = null;
				clusterer.clusters.push( cluster );
			}
		
		// Put all the unclustered visible markers into a cluster - the first
		// one it fits in, which favors pre-existing clusters.
		for ( i = 0; i < visibleMarkers.length; ++i ) {
			marker = visibleMarkers[i];
			if ( marker != null && ! marker.inCluster ) {
				for ( j = 0; j < clusterer.clusters.length; ++j ) {
					cluster = clusterer.clusters[j];
					if ( cluster != null && cluster.bounds.contains( marker.getPoint() ) ) {
						cluster.markers.push( marker );
						++cluster.markerCount;
						marker.inCluster = true;
					}
				}
			}
		}
		
		// Get rid of any clusters containing only a few markers.
		for ( i = 0; i < clusterer.clusters.length; ++i )
			if ( clusterer.clusters[i] != null && clusterer.clusters[i].markerCount < clusterer.minMarkersPerCluster ) {
			clusterer.ClearCluster( clusterer.clusters[i] );
			clusterer.clusters[i] = null;
		}
		
		// Shrink the clusters list.
		for ( i = clusterer.clusters.length - 1; i >= 0; --i )
			if ( clusterer.clusters[i] != null )
				break;
			else
				--clusterer.clusters.length;
		
		// Ok, we have our clusters.  Go through the markers in each
		// cluster and remove them from the map if they are currently up.
		for ( i = 0; i < clusterer.clusters.length; ++i ) {
			cluster = clusterer.clusters[i];
			if ( cluster != null ) {
				for ( j = 0; j < cluster.markers.length; ++j ) {
					marker = cluster.markers[j];
					if ( marker != null && marker.onMap ) {
						clusterer.map.removeOverlay( marker );
						marker.onMap = false;
					}
				}
			}
		}
		
		// Now make cluster-markers for any clusters that need one.
		for ( i = 0; i < clusterer.clusters.length; ++i ) {
			cluster = clusterer.clusters[i];
			if ( cluster != null && cluster.marker == null ) {
				// Figure out the average coordinates of the markers in this
				// cluster.
				var xTotal = 0.0, yTotal = 0.0;
				for ( j = 0; j < cluster.markers.length; ++j ) {
					marker = cluster.markers[j];
					if ( marker != null ) {
						xTotal += ( + marker.getPoint().lng() );
						yTotal += ( + marker.getPoint().lat() );
					}
				}
				
				var location = new GLatLng( yTotal / cluster.markerCount, xTotal / cluster.markerCount );
				var marker = new GMarker( location, { icon: clusterer.icon } );
				cluster.marker = marker;
				cluster.marker.icon = clusterer.icon;
				GEvent.addListener( marker, 'click', Clusterer.MakeCaller( Clusterer.PopUp, cluster ) );
			}
		}
	}
	
	// Display the visible markers not already up and not in clusters.
	for ( i = 0; i < visibleMarkers.length; ++i ) {
	marker = visibleMarkers[i];
	if ( marker != null && ! marker.onMap && ! marker.inCluster )
		{
		clusterer.map.addOverlay( marker );
		if ( marker.addedToMap != null )
		marker.addedToMap();
		marker.onMap = true;
		}
	}
	
	// Display the visible clusters not already up.
	for ( i = 0; i < clusterer.clusters.length; ++i ) {
		cluster = clusterer.clusters[i];
		if ( cluster != null && ! cluster.onMap && bounds.contains( cluster.marker.getPoint() ) ) {

			var image = 	'img/map/marker_count_%count.png';		
			defaultIcon = cluster.marker.icon;
			defaultIcon.image 	=  image.replace(/%count/gi, cluster.markerCount);

			clusterer.map.addOverlay( cluster.marker );
			cluster.onMap = true;
			}
		}
	
	// In case a cluster is currently popped-up, re-pop to get any new
	// markers into the infobox.
	Clusterer.RePop( clusterer );
};

Clusterer.aaa = function ( cluster ) {
	alert("");
};


Clusterer.PopUp = function ( cluster ) {
    var clusterer = cluster.clusterer;
    var html = '<div style="width:270px; height:140px; overflow:auto"><table width="250">';
    var n = 0;
    for ( var i = 0; i < cluster.markers.length; ++i ) {
		var marker = cluster.markers[i];
		if ( marker != null ){
			++n;
			html += '<tr><td>';
			if ( marker.getIcon().smallImage != null )
			html += '<img src="' + marker.getIcon().smallImage + '">';
			else
			html += '<img src="' + marker.getIcon().image + '" width="' + ( marker.getIcon().iconSize.width / 2 ) + '" height="' + ( marker.getIcon().iconSize.height / 2 ) + '">';
			html += '</td><td>' + marker.title + '</td></tr>';
			if ( n == clusterer.maxLinesPerInfoBox - 1 && cluster.markerCount > clusterer.maxLinesPerInfoBox  )
			{
			html += '<tr><td colspan="2">...and ' + ( cluster.markerCount - n ) + ' more</td></tr>';
			break;
			}
	    }
	}
    html += '</table></div>';
    clusterer.map.closeInfoWindow();
    cluster.marker.openInfoWindowHtml( html );
    clusterer.poppedUpCluster = cluster;
};


Clusterer.RePop = function ( clusterer )
    {
    if ( clusterer.poppedUpCluster != null )
	Clusterer.PopUp( clusterer.poppedUpCluster );
    };


Clusterer.PopDown = function ( clusterer )
    {
    clusterer.poppedUpCluster = null;
    };


Clusterer.prototype.ClearCluster = function ( cluster )
    {
    var i, marker;

    for ( i = 0; i < cluster.markers.length; ++i )
	if ( cluster.markers[i] != null )
	    {
	    cluster.markers[i].inCluster = false;
	    cluster.markers[i] = null;
	    }
    cluster.markers.length = 0;
    cluster.markerCount = 0;
    if ( cluster == this.poppedUpCluster )
	this.map.closeInfoWindow();
    if ( cluster.onMap )
	{
	this.map.removeOverlay( cluster.marker );
	cluster.onMap = false;
	}
    };


// This returns a function closure that calls the given routine with the
// specified arg.
Clusterer.MakeCaller = function ( func, arg )
    {
    return function () { func( arg ); };
    };


// Augment GMarker so it handles markers that have been created but
// not yet addOverlayed.

GMarker.prototype.setMap = function ( map )
    {
    this.map = map;
    };

GMarker.prototype.addedToMap = function ()
    {
    this.map = null;
    };

GMarker.prototype.origOpenInfoWindow = GMarker.prototype.openInfoWindow;
GMarker.prototype.openInfoWindow = function ( node, opts )
    {
    if ( this.map != null )
	return this.map.openInfoWindow( this.getPoint(), node, opts );
    else
	return this.origOpenInfoWindow( node, opts );
    };

GMarker.prototype.origOpenInfoWindowHtml = GMarker.prototype.openInfoWindowHtml;
GMarker.prototype.openInfoWindowHtml = function ( html, opts )
    {
    if ( this.map != null )
	return this.map.openInfoWindowHtml( this.getPoint(), html, opts );
    else
	return this.origOpenInfoWindowHtml( html, opts );
    };

GMarker.prototype.origOpenInfoWindowTabs = GMarker.prototype.openInfoWindowTabs;
GMarker.prototype.openInfoWindowTabs = function ( tabNodes, opts )
    {
    if ( this.map != null )
	return this.map.openInfoWindowTabs( this.getPoint(), tabNodes, opts );
    else
	return this.origOpenInfoWindowTabs( tabNodes, opts );
    };

GMarker.prototype.origOpenInfoWindowTabsHtml = GMarker.prototype.openInfoWindowTabsHtml;
GMarker.prototype.openInfoWindowTabsHtml = function ( tabHtmls, opts )
    {
    if ( this.map != null )
	return this.map.openInfoWindowTabsHtml( this.getPoint(), tabHtmls, opts );
    else
	return this.origOpenInfoWindowTabsHtml( tabHtmls, opts );
    };

GMarker.prototype.origShowMapBlowup = GMarker.prototype.showMapBlowup;
GMarker.prototype.showMapBlowup = function ( opts )
    {
    if ( this.map != null )

	return this.map.showMapBlowup( this.getPoint(), opts );
    else
	return this.origShowMapBlowup( opts );
    };