// 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


var defaultMaxVisibleMarkers = 150;
var defaultGridSize = 5;
var defaultMinMarkersPerCluster = 5;
var defaultMaxLinesPerInfoBox = 10;
var defaultIcon = G_DEFAULT_ICON;

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

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

    GEvent.addListener( map, 'zoomend', ClustererMakeCaller( ClustererDisplay, this ) );
    GEvent.addListener( map, 'moveend', ClustererMakeCaller( ClustererDisplay, this ) );
    GEvent.addListener( map, 'infowindowclose', ClustererMakeCaller( ClustererPopDown, this ) );
    }


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


// Call this to add a marker.
Clusterer.prototype.AddMarker = function ( marker, title )
    {
    // Putting the map into a marker property is not mentioned in the API,
    // but it lets up pop up an infobox for markers which have not yet been
    // added to the map.
    //marker.map = this.map;
    // Unfortunately that no longer works as of v2.44.  The code below
    // works but is much slower.  No good solution for now.
    //this.map.addOverlay( marker );
    //this.map.removeOverlay( marker );

    marker.title = title;
    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 ( j = 0; j < this.clusters.length; ++j )
		{
		cluster = clusterer.clusters[j];
		if ( cluster != null )
		    {
		    for ( 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 );
			clusterer.clusters[j] = null;
			}
		    else if ( cluster == this.poppedUpCluster )
			ClustererRePop( this );
		    }
		}
	    this.markers[i] = null;
	    break;
	    }
    this.DisplayLater();
    }

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


function ClustererDisplay( 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();
    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 = [];
    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 );
		marker = new GMarker( location, clusterer.icon );
		cluster.marker = marker;
		GEvent.addListener( marker, 'click', ClustererMakeCaller( ClustererPopUp, 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 );
	    var title = marker.title;
	    if ( title != null )
		ClustererSetTooltip( marker, title );
	    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() ) )
	    {
	    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.
    ClustererRePop( clusterer );
    }

function ClustererPopUp( cluster ) {
    var clusterer = cluster.clusterer;
    var html = '';
    html += '<center><b>Nodes in dieser Umgebung:</b></center><br />';
    html += '<div class="marker">';
    html += '<table>';
    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>' + getZoomLink(marker) + '</td></tr>';
	}
    }
    html += '</table></div>';
    clusterer.map.closeInfoWindow();
    cluster.marker.openInfoWindowHtml( html );
    clusterer.poppedUpCluster = cluster;
}

function getZoomLink(marker) {
	//var lat = marker.getPoint().lat();
	//var lon = marker.getPoint().lng();
	return '<a href="javascript:zoomToNode(\'' + marker.title + '\', -1)">' + marker.title + '</a>'
	//return '<a href="javascript:zoomToNode(\'' + marker.title + '\', ' + lat + ', ' + lon + ')">' + marker.title + '</a>';
}

function ClustererRePop( clusterer )
    {
    if ( clusterer.poppedUpCluster != null )
	ClustererPopUp( poppedUpCluster );
    }


function ClustererPopDown( 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.
function ClustererMakeCaller( func, arg )
    {
    return function () { func( arg ); };
    }


function ClustererSetTooltip( marker, title )
    {
    var topElement = null;
    if ( marker.transparentIcon != null )
	topElement = marker.transparentIcon;
    else if ( marker.imageMap != null )
	topElement = marker.imageMap;
    else if ( marker.iconImage != null )
	topElement = marker.iconImage;
    else if ( marker.images != null && marker.images[0] != null )
	topElement = marker.images[0];
    if ( topElement != null )
	topElement.title = ClustererDeHtmlize( title );
    }


function ClustererEntityToIso8859( inStr )
    {
    var outStr = '';
    for ( var i = 0; i < inStr.length; ++i )
	{
	var c = inStr.charAt( i );
	if ( c != '&' )
	    outStr += c;
	else
	    {
	    var semi = inStr.indexOf( ';', i );
	    if ( semi == -1 )
		outStr += c;
	    else
		{
		var entity = inStr.substring( i + 1, semi );
		if ( entity == 'iexcl' ) outStr += '¡';
		else if ( entity == 'copy' ) outStr += '©';
		else if ( entity == 'laquo' ) outStr += '«';
		else if ( entity == 'reg' ) outStr += '®';
		else if ( entity == 'deg' ) outStr += '°';
		else if ( entity == 'raquo' ) outStr += '»';
		else if ( entity == 'iquest' ) outStr += '¿';
		else if ( entity == 'Agrave' ) outStr += 'À';
		else if ( entity == 'Aacute' ) outStr += 'Á';
		else if ( entity == 'Acirc' ) outStr += 'Â';
		else if ( entity == 'Atilde' ) outStr += 'Ã';
		else if ( entity == 'Auml' ) outStr += 'Ä';
		else if ( entity == 'Aring' ) outStr += 'Å';
		else if ( entity == 'AElig' ) outStr += 'Æ';
		else if ( entity == 'Ccedil' ) outStr += 'Ç';
		else if ( entity == 'Egrave' ) outStr += 'È';
		else if ( entity == 'Eacute' ) outStr += 'É';
		else if ( entity == 'Ecirc' ) outStr += 'Ê';
		else if ( entity == 'Euml' ) outStr += 'Ë';
		else if ( entity == 'Igrave' ) outStr += 'Ì';
		else if ( entity == 'Iacute' ) outStr += 'Í';
		else if ( entity == 'Icirc' ) outStr += 'Î';
		else if ( entity == 'Iuml' ) outStr += 'Ï';
		else if ( entity == 'Ntilde' ) outStr += 'Ñ';
		else if ( entity == 'Ograve' ) outStr += 'Ò';
		else if ( entity == 'Oacute' ) outStr += 'Ó';
		else if ( entity == 'Ocirc' ) outStr += 'Ô';
		else if ( entity == 'Otilde' ) outStr += 'Õ';
		else if ( entity == 'Ouml' ) outStr += 'Ö';
		else if ( entity == 'Oslash' ) outStr += 'Ø';
		else if ( entity == 'Ugrave' ) outStr += 'Ù';
		else if ( entity == 'Uacute' ) outStr += 'Ú';
		else if ( entity == 'Ucirc' ) outStr += 'Û';
		else if ( entity == 'Uuml' ) outStr += 'Ü';
		else if ( entity == 'Yacute' ) outStr += 'Ý';
		else if ( entity == 'szlig' ) outStr += 'ß';
		else if ( entity == 'agrave' ) outStr += 'à';
		else if ( entity == 'aacute' ) outStr += 'á';
		else if ( entity == 'acirc' ) outStr += 'â';
		else if ( entity == 'atilde' ) outStr += 'ã';
		else if ( entity == 'auml' ) outStr += 'ä';
		else if ( entity == 'aring' ) outStr += 'å';
		else if ( entity == 'aelig' ) outStr += 'æ';
		else if ( entity == 'ccedil' ) outStr += 'ç';
		else if ( entity == 'egrave' ) outStr += 'è';
		else if ( entity == 'eacute' ) outStr += 'é';
		else if ( entity == 'ecirc' ) outStr += 'ê';
		else if ( entity == 'euml' ) outStr += 'ë';
		else if ( entity == 'igrave' ) outStr += 'ì';
		else if ( entity == 'iacute' ) outStr += 'í';
		else if ( entity == 'icirc' ) outStr += 'î';
		else if ( entity == 'iuml' ) outStr += 'ï';
		else if ( entity == 'ntilde' ) outStr += 'ñ';
		else if ( entity == 'ograve' ) outStr += 'ò';
		else if ( entity == 'oacute' ) outStr += 'ó';
		else if ( entity == 'ocirc' ) outStr += 'ô';
		else if ( entity == 'otilde' ) outStr += 'õ';
		else if ( entity == 'ouml' ) outStr += 'ö';
		else if ( entity == 'oslash' ) outStr += 'ø';
		else if ( entity == 'ugrave' ) outStr += 'ù';
		else if ( entity == 'uacute' ) outStr += 'ú';
		else if ( entity == 'ucirc' ) outStr += 'û';
		else if ( entity == 'uuml' ) outStr += 'ü';
		else if ( entity == 'yacute' ) outStr += 'ý';
		else if ( entity == 'yuml' ) outStr += 'ÿ';
		else if ( entity == 'nbsp' ) outStr += ' ';
		else if ( entity == 'lt' ) outStr += '<';
		else if ( entity == 'gt' ) outStr += '>';
		else if ( entity == 'amp' ) outStr += '&';
		else outStr += '&' + entity + ';';
		i += entity.length + 1;
		}
	    }
	}
    return outStr;
    }


function ClustererDeEntityize( inStr )
    {
    var outStr = '';
    for ( var i = 0; i < inStr.length; ++i )
	{
	var c = inStr.charAt( i );
	if ( c != '&' )
	    outStr += c;
	else
	    {
	    var semi = inStr.indexOf( ';', i );
	    if ( semi != -1 )
		i = semi;
	    }
	}
    return outStr;
    }


function ClustererDeElementize( inStr )
    {
    var outStr = '';
    for ( var i = 0; i < inStr.length; ++i )
	{
	var c = inStr.charAt( i );
	if ( c != '<' )
	    outStr += c;
	else
	    {
	    var gt = inStr.indexOf( '>', i );
	    if ( gt != -1 )
		i = gt;
	    }
	}
    return outStr;
    }


function ClustererDeHtmlize( str )
    {
    return ClustererDeEntityize( ClustererEntityToIso8859( ClustererDeElementize( str ) ) );
    }