local.js

var map;

var located = false;
function onLocationError(e) {
    if(!located){
	var map = L.map('map').setView([55.950, -3.203], 16);
	located = true;
    }
    alert(e.message);
}

function resetMap(map){
    document.getElementById('map').innerHTML = "";
    if (typeof map === 'undefined')return;
    try{
	map.off();
	map.remove();
	map = undefined;
    }catch(e){
	console.log("Tried to remove a defined map, but failed: "+JSON.stringify(e));
    }
}


// === Some cookie parameters === 
var cookiename = "mapinfo"; // name for this cookie 
var expiredays = 7; // number of days before cookie expiry 

function setCookie(){
    if (typeof map === 'undefined')return;

    var mapcenter = map.getCenter();
    var cookietext = cookiename+"="+mapcenter.lat+"|"+mapcenter.lng+"|"+map.getZoom(); 
    if (expiredays) { 
	var exdate=new Date(); 
	exdate.setDate(exdate.getDate()+expiredays); 
	cookietext += ";expires="+exdate.toGMTString(); 
    } 
    // == write the cookie == 
    document.cookie=cookietext; 
}
function getParam(val) {
      var paramData = location.hash.substr(1);
      if(typeof paramData === 'undefined' || paramData === ''){
	paramData = location.search.substr(1);
      }
      var params = paramData.split("&");
      for(param of params){
	var kv = param.split("=");
	if(kv[0] === val) return kv[1];
      }
}
function mapstartFromParams(){
   var paramLat = getParam("lat");
    if(typeof paramLat  === 'undefined'){
        return undefined;
    }else{
        // We're using the URL to override
        paramLon = getParam("lon");
        paramZoom = getParam("zoom");
        return [paramLat,paramLon,paramZoom];
    }
}
function mapstartFromCookie(){
    if (document.cookie.length>0) { 
    	cookieStart = document.cookie.indexOf(cookiename + "="); 
	if (cookieStart!=-1) { 
    	    cookieStart += cookiename.length+1; 
	    cookieEnd=document.cookie.indexOf(";",cookieStart); 
	    if (cookieEnd==-1) { 
    		cookieEnd=document.cookie.length; 
	    } 
	    cookietext = document.cookie.substring(cookieStart,cookieEnd); 
                    
	    // == split the cookie text and create the variables == 
	    bits = cookietext.split("|"); 
	    lat = parseFloat(bits[0]); 
	    lon = parseFloat(bits[1]); 
	    zoom = parseInt(bits[2]); 
	    return [lat, lon, zoom];

	} 
    } 
    return null;
}

function initMaps(){
    map =  L.map('map');

    var cookieStart = mapstartFromCookie();
    var paramStart = mapstartFromParams();

    try{
	map.setView([paramStart[0],  paramStart[1]],  paramStart[2]);
	console.log("Initialised map location from query parameters");
    }catch(e){
	console.log("Couldn't set map from params.  Falling back to cookie");
	try{
	    map.setView([cookieStart[0],  cookieStart[1]],  cookieStart[2]);
	}catch(e){
	    console.log("Couldn't set map from cookie.  Falling back to defaults");
	    map.setView([55.951,-3.200],15);
	}
    }


    var osm = L.tileLayer('/osm/{z}/{x}/{y}.png', {
	maxZoom: 17,
	minZoom: 5,
	attribution: 'Map data &copy; <a href="http://openstreetmap.org">OpenStreetMap</a> contributors, ' +
		'<a href="http://creativecommons.org/licenses/by-sa/2.0/">CC-BY-SA</a>, ',
	id: 'bear.mapnik'
    });

    var contours = L.tileLayer('/tiles/contours/{z}/{x}/{y}.png', {
	maxZoom: 16,
	minZoom: 8,
	id: 'bear.contours',
	opacity: 0.3
    });

    var osgb = L.tileLayer('/tiles/grid/{z}/{x}/{y}.png', {
	maxZoom: 16,
	minZoom: 12,
	id: 'bear.osgb'
    });

    var dykes = L.tileLayer('/tiles/dykes/{z}/{x}/{y}.png', {
	maxZoom: 16,
	id: 'bear.dykes',
	opacity: 0.5,
	attribution: '| Geology layers: Based upon DiGMapGB-625, with the permission of the British Geological Survey'
    });

    var faults = L.tileLayer('/tiles/faults/{z}/{x}/{y}.png', {
	maxZoom: 16,
	id: 'bear.faults',
	opacity: 0.5,
	attribution: '| Geology layers: Based upon DiGMapGB-625, with the permission of the British Geological Survey'
    });

    var solid = L.tileLayer('/tiles/solid/{z}/{x}/{y}.png', {
	maxZoom: 16,
	id: 'bear.solid',
	opacity: 1.0,
	attribution: '| Geology layers: Based upon DiGMapGB-625, with the permission of the British Geological Survey'
    });

    var constituencies = L.tileLayer('/tiles/constituencies/{z}/{x}/{y}.png', {
	maxZoom: 17,
	id: 'bear.constituencies',
	opacity: 1.0,
	attribution: '| '
    });

    var ukconstituencies = L.tileLayer('/tiles/ukconstituencies/{z}/{x}/{y}.png', {
	maxZoom: 17,
	id: 'bear.ukconstituencies',
	opacity: 1.0,
	attribution: '| OS OpenData'
    });

    var councilwards = L.tileLayer('/tiles/council_wards/{z}/{x}/{y}.png', {
	maxZoom: 17,
	id: 'bear.councilwards',
	opacity: 1.0,
	attribution: '| OS OpenData'
    });

    var regions = L.tileLayer('/tiles/regions/{z}/{x}/{y}.png', {
	maxZoom: 17,
	id: 'bear.regions',
	opacity: 1.0,
	attribution: '| '
    });

    var newMarilynLayer = new L.MarkerClusterGroup({
    	iconCreateFunction: function(cluster) {
    	    var n = '<b>' + cluster.getChildCount() + '</b>';
	    return new L.DivIcon({ 
		html: n,
		className: 'mycluster',
		iconSize: L.point(40, 40)
	    });
	}
    });

    for(i=0;i<marilynsArray.length;i++){
	var m = L.marker([marilynsArray[i].lat, marilynsArray[i].lng]).bindPopup(marilynsArray[i].hill_name);
	newMarilynLayer.addLayer(m);
    }

    L.control.search({
      	url: 'http://www.rasilon.net/find_postcode.php?q={s}',
	textPlaceholder: 'Postcode...',
	collapsed: false,
	//markerIcon: new L.Icon({iconUrl:'data/custom-icon.png', iconSize: [20,20]}),
	markerLocation: true
	}).addTo(map);


    osm.addTo(map);
    //contours.addTo(map);
    //osgb.addTo(map);

    if(getParam("marilyns")){
	newMarilynLayer.addTo(map);
    }

    if(getParam("solid")){
	solid.addTo(map);
    }

    if(getParam("dykes")){
	dykes.addTo(map);
    }

    if(getParam("faults")){
	faults.addTo(map);
    }

    if(getParam("constituencies")){
	constituencies.addTo(map);
    }

    if(getParam("ukconstituencies")){
	ukconstituencies.addTo(map);
    }

    if(getParam("councilwards")){
	councilwards.addTo(map);
    }


    var baseMaps = {
	"Mapnik": osm
    };
    var overlayMaps = {
	"Contours": contours,
	"OS Grid": osgb,
	"Solid": solid,
	"Dykes": dykes,
	"Faults": faults,
	"Marilyn Markers": newMarilynLayer,
	"Scottish Constituencies": constituencies,
	"Scottish Regions": regions,
	"UK Constituencies": ukconstituencies,
	"UK Council Wards": councilwards
    };

    var layers = L.control.layers(baseMaps, overlayMaps);

    layers.addTo(map);

    map.addControl(new L.Control.Permalink({text: 'Permalink', layers: layers}));


    var solidExplanationMarker = L.marker([0.0,0.0]).bindPopup("No popup content yet!");

    map.on('click', function(e) {
	if(map.hasLayer(solid)){
	    var popupData = "Not Implemented Yet.<br>At "+e.latlng.lng+" "+e.latlng.lat;

	    var xmlhttp = new XMLHttpRequest();
	    xmlhttp.onreadystatechange = function() {
		if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
		    var r = JSON.parse(xmlhttp.responseText);

		    var groupName = decodeURI(r.lex_d);
		    var descr = decodeURI(r.rcs_d);
		    var minMY = decodeURI(r.min_my);
		    var maxMY = decodeURI(r.max_my);
		    var maxPeriod = decodeURI(r.max_period);
		    var minPeriod = decodeURI(r.min_period);

		    var popupData = "";
		    if(typeof groupName == "undefined" || groupName === ""){
			popupData = "Unknown bedrock.";
		    }else{
			popupData = "<table class=\"descrTable\">"+
				    "<tr><td>Name</td><td> "+groupName+"</td></tr>"+
				    "<tr><td>Description</td><td>"+descr+"</td></tr>"+
				    "<tr><td>Deposited between</td><td>"+
					maxMY+
					" million years ago ("+
					maxPeriod+
					"),<br>and<br>"+
					minMY+
					" million years ago ("+
					minPeriod+
					").</td></tr>\n</table>"
				    ;
		    }
		    solidExplanationMarker
			.setLatLng(e.latlng)
			.addTo(map)
			.setPopupContent(popupData)
			.openPopup();
		}
	    }
	    xmlhttp.open("GET", "http://www.rasilon.net/descr_for_location.cgi?lat="+e.latlng.lat+"&lng="+e.latlng.lng, true);
	    xmlhttp.send();

	}else{
	    //alert("No solid");
	}
    });

}