/*+********************************************************************* 
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

(C) 2008 Harald Kirsch (pifpafpuf at gmx dot de)
************************************************************************/
function updateScale(evt) {
  var scale = this.getScale();
  var size = this.getSize();
  var factor = 25.4/72.0*1e-6*scale;
  var xkm = (size.w*factor).toFixed(3)
  var ykm = (size.h*factor).toFixed(3)
  var e = document.getElementById('currentscale');
  e.innerHTML = scale.toFixed(0) 
    + ", "+xkm+"&times;"+ykm+" km<sup style='font-size:smaller'>2</sup>";
  updateLocation.call(this, evt);
}
function updateLocation(evt) {
  var lonlat = p2p(p900913, p4326, this.getCenter());
  var href = ""+location.protocol+"//"
    + location.hostname
    + (location.port ? ":"+location.port : "") 
    + location.pathname.replace(/\/upload/, "/map")
    + "?lon="+lonlat.lon.toFixed(4)
    + "&lat="+lonlat.lat.toFixed(4)
    + "&zoom="+this.getZoom()
    + "&maph="+parseInt(document.getElementById('map').style.height)
    + "&layer="+map.baseLayer.name
    ;
  document.getElementById('permalink').href = href;
  location.url = href;
}
var mouseposElem = {element: document.getElementById('mousepos')};
var options = {
  projection : "EPSG:900913",
  controls: [new OpenLayers.Control.MouseDefaults(),
	     new OpenLayers.Control.LayerSwitcher(),
	     new OpenLayers.Control.PanZoomBar(),
	     //new OpenLayers.Control.MousePosition(mouseposElem)
	     ],
};

var map = new OpenLayers.Map('map', options);

var layerTilesAtHome = new OpenLayers.Layer.OSM.Osmarender("Osmarender");
map.addLayer(layerTilesAtHome);

var layerMapnik = new 
  OpenLayers.Layer.OSM.Mapnik("Mapnik");
map.addLayer(layerMapnik);

var layerCycle = new 
  OpenLayers.Layer.OSM.CycleMap("Cycle");
map.addLayer(layerCycle);

var layerTrails = new
  OpenLayers.Layer.OSM("Tracks", "http://topo.geofabrik.de/trails/${z}/${x}/${y}.png", 
		       {numZoomLevels: 16, isBaseLayer:true});
map.addLayer(layerTrails);

/**
var layerGoogleStreet = new 
  OpenLayers.Layer.Google("Google Streets", 
 			  { type: G_NORMAL_MAP, 
			      'sphericalMercator': true, 
 			      numZoomLevels:19 } );
map.addLayer(layerGoogleStreet);
**/

// have to figure out how this can be done automatically
Proj4js.defs["EPSG:54004"] = 
"+proj=merc +lon_0=0 +k=1 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs ";
Proj4js.defs["EPSG:54004"] = "+proj=merc +lat_ts=0 +lon_0=0 +k=1.000000 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m  no_defs"
Proj4js.defs["EPSG:900913"] = "+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext  +no_defs";

p54004 = new Proj4js.Proj("EPSG:54004");
p4326 = new Proj4js.Proj("EPSG:4326");
p900913 = new Proj4js.Proj("EPSG:900913");

function sizeMap(deltaPx) { 
  var e = document.getElementById('map');
  var h = e.style.height;
  if( h=='' ) h = window.getComputedStyle(e, null).height;
  var height = parseInt(h)+deltaPx;
  if( height<100 ) return;
  e.style.height = ""+ height + 'px';
  map.updateSize();
};
/**
 * convert from one projection to other. 
 * @param Proj4js.Proj pFrom input projection
 * @param Proj4js.Proj pTo output projection
 * @param OpenLayers.LonLat lonlat value to convert
 */
function p2p(pFrom, pTo, lonlat) {
  var xy = {x: lonlat.lon, y:lonlat.lat};
  xy = Proj4js.transform(pFrom, pTo, xy);
  return new OpenLayers.LonLat(xy.x, xy.y);  
};
function mapFullsize() {
  var maph = window.innerHeight-100;
  document.getElementById('map').style.height = ""+maph+"px";

}
// parse URL parameters for lat, lon and zoom
var floatreString = "([-]?[0-9]+([.][0-9]+)?)($|&)";
var paramDef = {
  lat : [new RegExp("[?&]lat="+floatreString), null],
  lon : [new RegExp("[?&]lon="+floatreString),  null],
  zoom : [new RegExp("[?&]zoom=([0-9]|1[0-9])($|&)"), null],
  maph : [new RegExp("[?&]maph=([0-9][0-9][0-9][0-9]?)($|&)"), null],
  layer : [new RegExp("[?&]layer=([A-Za-z]+)($|&)"), "Mapnik"],
};
var params = {};
for(key in paramDef) {
  var m = location.search.match(paramDef[key][0]);
  eval("var "+key+" = (m==null) ? paramDef[key][1] : m[1]");
 };


// initialize the map coordinates, zoom, size and layer from the URL
// parameters or from defaults. For the coordinates we remember
// whether we used the default. If yes, a track just loaded is allowed
// to override the settings to zoom to its extend.
if( lat && lon ) {
  lonlatIsDefault = false;
  var lonlat = new OpenLayers.LonLat(lon, lat);
} else {
  lonlatIsDefault = true;
  var lonlat = new OpenLayers.LonLat(6.8518,51.2462);
}
lonlat = p2p(p4326, p900913, lonlat);

if( zoom ) {
  zoomIsDefault = false;
} else {
  zoomIsDefault = true;
  zoom = 6;
}

if( maph ) {
  document.getElementById('map').style.height = ""+maph+"px";
  map.updateSize();
} else {
  mapFullsize();
}
var l = map.getLayersByName(layer);
if( l && l.length>0 ) map.setBaseLayer(l[0]);

map.events.register("zoomend", map, updateScale);
map.events.register("moveend", map, updateLocation);

// called at the end of the generated tail of index.html, just before
// the track points are created.
function initMapCoords(lonlat, zoom, map) {
  map.setCenter(lonlat, zoom, false, false);
  updateScale.apply(map, null);
}

// TODO: Arrrgh, need to call map-center anyway so that GpxTrack, when
// initialized, can immediately register the popup with the map. Need
// to change this to lazy popup-initialization, but since Javascript
// does not have private members and compilation, this can become
// tedious.
//map.setCenter(lonlat, zoom, false, false);