Initial commit

lib/assets/javascripts/dashboard/data/layers-collection.js

@@ -0,0 +1,70 @@
+const Backbone = require('backbone');
+const MapLayer = require('dashboard/data/map-layer-model');
+const checkAndBuildOpts = require('builder/helpers/required-opts');
+
+const TILED_LAYER_TYPE = 'Tiled';
+const CARTODB_LAYER_TYPE = 'CartoDB';
+const TORQUE_LAYER_TYPE = 'torque';
+
+const REQUIRED_OPTS = [
+  'configModel'
+];
+
+const LayersCollection = Backbone.Collection.extend({
+  model: MapLayer,
+
+  initialize: function (models, options) {
+    checkAndBuildOpts(options, REQUIRED_OPTS, this);
+
+    this.comparator = function (m) {
+      return parseInt(m.get('order'), 10);
+    };
+    this.bind('add', this._assignIndexes);
+    this.bind('remove', this._assignIndexes);
+  },
+
+  url: function (method) {
+    var version = this._configModel.urlVersion('layer', method);
+    return `/api/${version}/maps/${this.map.id}/layers`;
+  },
+
+  parse: function (data) {
+    return data.layers;
+  },
+
+  /**
+   * each time a layer is added or removed
+   * the index should be recalculated
+   */
+  _assignIndexes: function (model, col, options) {
+    if (this.size() > 0) {
+      // Assign an order of 0 to the first layer
+      this.at(0).set({ order: 0 });
+
+      if (this.size() > 1) {
+        var layersByType = {};
+        for (var i = 1; i < this.size(); ++i) {
+          var layer = this.at(i);
+          var layerType = layer.get('type');
+          layersByType[layerType] = layersByType[layerType] || [];
+          layersByType[layerType].push(layer);
+        }
+
+        var lastOrder = 0;
+        var sortedTypes = [CARTODB_LAYER_TYPE, TORQUE_LAYER_TYPE, TILED_LAYER_TYPE];
+        for (var index = 0; index < sortedTypes.length; ++index) {
+          var type = sortedTypes[index];
+          var layers = layersByType[type] || [];
+          for (var j = 0; j < layers.length; ++j) {
+            var layerModel = layers[j];
+            layerModel.set({
+              order: ++lastOrder
+            });
+          }
+        }
+      }
+    }
+  }
+});
+
+module.exports = LayersCollection;