Allow user to add custom layers

index.html

@@ -141,6 +141,23 @@
         </div>
     </div>
 
+    <!-- Layers modal window -->
+    <div class="modal fade" id="custom_layers" tabindex="-1" role="dialog" aria-labelledby="Layers window" aria-hidden="true">
+        <div class="modal-dialog modal-lg" role="document">
+                    <h4 class="modal-title">Customize layers</h4>
+                </div>
+                <div class="modal-body">
+                    <input class="form-control" type="text" id="layer_name" spellcheck="true" wrap="off" placeholder="Custom layer name. (ex: OpenStreetMap)"></input>
+                    <input class="form-control" type="text" id="layer_url" spellcheck="false" wrap="off" placeholder="Custom layer URL. (ex: https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png)"></input>
+
+                    <button type="button" id="custom_layers_add_base" class="btn btn-success">Add base layer</button>
+                    <button type="button" id="custom_layers_add_overlay" class="btn btn-success">Add overlay</button>
+                    <button type="button" id="custom_layers_remove" class="btn btn-danger">Remove selection</button>
+                    <table id="custom_layers_table"></table>
+                </div>
+            </div>
+        </div>
+    </div>
 
     <!-- About modal window -->
     <div class="modal fade" id="about" tabindex="-1" role="dialog" aria-labelledby="About window" aria-hidden="true">

js/Map.js

@@ -120,6 +120,8 @@ BR.Map = {
 
         L.control.scale().addTo(map);
 
+        new BR.Layers().init(map, layersControl, baseLayers, overlays);
+
         // expose map instance for console debugging
         BR.debug = BR.debug || {};
         BR.debug.map = map;

js/control/Layers.js

@@ -0,0 +1,134 @@
+BR.Layers = L.Class.extend({
+
+    _loadLayers: function() {
+        this._customLayers = {};
+
+        if (BR.Util.localStorageAvailable()) {
+            var layers = JSON.parse(localStorage.getItem("map/customLayers"));
+            for (a in layers) {
+                this._addLayer(a, layers[a].layer, layers[a].isOverlay);
+            }
+        }
+    },
+
+    _loadTable: function() {
+        var layersData = [];
+        for (layer in this._customLayers) {
+            layersData.push([layer, this._customLayers[layer].layer._url, this._customLayers[layer].isOverlay ? "Overlay" : "Layer"]);
+        }
+        if (this._layersTable != null) {
+            this._layersTable.destroy();
+        }
+
+        this._layersTable =  $('#custom_layers_table').DataTable({
+            data: layersData,
+            info: false,
+            searching: false,
+            paging: false,
+            columns: [
+            { title: "Name" },
+            { title: "URL" },
+            { title: "Type" }
+            ]
+        });
+    },
+
+    init: function(map, layersControl, baseLayers, overlays) {
+        this._layersControl = layersControl;
+        this._map = map;
+        this._layers = {}
+        for (var l in overlays)
+            this._layers[l] = [overlays[l], true];
+        for (var l in baseLayers)
+            this._layers[l] = [baseLayers[l], false];
+
+        L.DomUtil.get('custom_layers_add_base').onclick = L.bind(this._addBaseLayer, this);
+        L.DomUtil.get('custom_layers_add_overlay').onclick = L.bind(this._addOverlay, this);
+        L.DomUtil.get('custom_layers_remove').onclick = L.bind(this._remove, this);
+
+        this._loadLayers();
+        this._loadTable();
+
+        var table = this._layersTable;
+        $('#custom_layers_table tbody').on( 'click', 'tr', function () {
+            if ( $(this).hasClass('selected') ) {
+                $(this).removeClass('selected');
+            } else {
+                table.$('tr.selected').removeClass('selected');
+                $(this).addClass('selected');
+            }
+        });
+
+        addLayer = L.easyButton(
+            'fa-plus-square',
+            function () {
+                $('#custom_layers').modal();
+            },
+            'Add or remove custom layers',
+            {
+                position: 'topright'
+            }
+            ).addTo(map);
+    },
+
+    _remove: function(evt) {
+        var row = this._layersTable.row('.selected').data();
+        if (row != null) {
+            var name = row[0];
+            this._layersControl.removeLayer(this._customLayers[name].layer);
+            this._map.removeLayer(this._customLayers[name].layer);
+            delete this._customLayers[name];
+            this._layersTable.row('.selected').remove().draw( false );
+            this._sync();
+        }
+    },
+
+    _addFromInput: function(isOverlay) {
+        var layer_name = L.DomUtil.get('layer_name').value;
+        var layer_url = L.DomUtil.get('layer_url').value;
+        if (layer_name.length > 0 && layer_url.length > 0)
+            this._addLayer(layer_name, layer_url, isOverlay);
+    },
+
+    _addBaseLayer: function(evt) {
+        this._addFromInput(false);
+    },
+    _addOverlay: function(evt) {
+        this._addFromInput(true);
+    },
+
+    _addLayer: function(layerName, layerUrl, isOverlay) {
+        if (layerName in this._layers)
+            return
+
+        if (layerName in this._customLayers)
+            return
+
+        try {
+            var layer = L.tileLayer(layerUrl);
+
+            this._customLayers[layerName] = {layer: layer, isOverlay: isOverlay};
+
+            if (isOverlay) {
+                this._layersControl.addOverlay(layer, layerName);
+            } else {
+                this._layersControl.addBaseLayer(layer, layerName);
+            }
+            this._loadTable();
+            this._sync();
+            return layer;
+        } catch (e) {
+            console.warn("Oops:", e);
+            return
+        }
+    },
+
+    _sync: function() {
+        if (BR.Util.localStorageAvailable()) {
+            localStorage.setItem("map/customLayers", JSON.stringify(this._customLayers, function(k, v) {
+                // dont write Leaflet.Layer in localStorage; simply keep the URL
+                return v._url || v;
+            }));
+        }
+    }
+});