app/views/browse/start.rjs

   1 page.replace_html :sidebar_title, 'Data'
   2 page.replace_html :sidebar_content, :partial => 'start'
   3 page << <<EOJ
   4   var browseBoxControl;
   5   var browseActive;
   6   var browseMode = "auto";
   7   var browseBounds;
   8   var browseFeatureList;
   9   var browseActiveFeature;
  10   var browseDataLayer;
  11   var browseSelectControl;
  12   var browseObjectList;
  13
  14   OpenLayers.Feature.Vector.style['default'].strokeWidth = 3;
  15   OpenLayers.Feature.Vector.style['default'].cursor = "pointer";
  16
  17   function startBrowse() {
  18     openSidebar({ onclose: stopBrowse });
  19
  20     var vectors = new OpenLayers.Layer.Vector();
  21
  22     browseBoxControl = new OpenLayers.Control.DrawFeature(vectors, OpenLayers.Handler.RegularPolygon, {
  23       handlerOptions: {
  24         sides: 4,
  25         snapAngle: 90,
  26         irregular: true,
  27         persist: true,
  28         callbacks: { done: endDrag }
  29       }
  30     });
  31     map.addControl(browseBoxControl);
  32
  33     map.events.register("moveend", map, showData);
  34     map.events.triggerEvent("moveend");
  35
  36     browseActive = true;
  37   }
  38
  39   function showData() {
  40     if (browseMode == "auto") {
  41       if (map.getZoom() >= 15) {
  42           useMap();
  43       } else {
  44           $("browse_status").innerHTML = "Zoom in or Select an area of the map to view.";
  45       }
  46     }
  47   }
  48
  49   function stopBrowse() {
  50     if (browseActive) {
  51       browseActive = false;
  52
  53       if (browseDataLayer) {
  54         browseDataLayer.destroy();
  55         browseDataLayer = null;
  56       }
  57
  58       if (browseSelectControl) {
  59         browseSelectControl.destroy();
  60         browseSelectControl = null;
  61       }
  62
  63       if (browseBoxControl) {
  64         browseBoxControl.destroy();
  65         browseBoxControl = null;
  66       }
  67
  68       if (browseActiveFeature) {
  69         browseActiveFeature.destroy();
  70         browseActiveFeature = null;
  71       }
  72
  73       map.dataLayer.setVisibility(false);
  74       map.events.unregister("moveend", map, showData);
  75     }
  76   }
  77
  78   function startDrag() {
  79     $("browse_select_box").innerHTML='Drag a box on the map to select an area';
  80
  81     browseBoxControl.activate();
  82
  83     return false;
  84   };
  85
  86   $("browse_select_box").onclick = startDrag;
  87
  88   function useMap() {
  89     var bounds = map.getExtent();
  90     var projected = bounds.clone().transform(map.getProjectionObject(), epsg4326);
  91
  92     if (!browseBounds || !browseBounds.containsBounds(projected)) {
  93       var center = bounds.getCenterLonLat();
  94       var tileWidth = bounds.getWidth() * 1.2;
  95       var tileHeight = bounds.getHeight() * 1.2;
  96       var tileBounds = new OpenLayers.Bounds(center.lon - (tileWidth / 2),
  97                                              center.lat - (tileHeight / 2),
  98                                              center.lon + (tileWidth / 2),
  99                                              center.lat + (tileHeight / 2));
 100
 101       browseBounds = tileBounds;
 102       getData(tileBounds);
 103
 104       browseMode = "auto";
 105
 106       $("browse_select_view").style.display = "none";
 107     }
 108
 109     return false;
 110   }
 111
 112   $("browse_select_view").onclick = useMap;
 113
 114   function endDrag(bbox) {
 115     var bounds = bbox.getBounds();
 116     var projected = bounds.clone().transform(map.getProjectionObject(), epsg4326);
 117
 118     browseBoxControl.deactivate();
 119     browseBounds = projected;
 120     getData(bounds);
 121
 122     browseMode = "manual";
 123
 124     $("browse_select_box").innerHTML = "Manually select a different area";
 125     $("browse_select_view").style.display = "inline";
 126   }
 127
 128   function displayFeatureWarning() {
 129     $("browse_status").innerHTML = "";
 130
 131     var div = document.createElement("div");
 132
 133     var p = document.createElement("p");
 134     p.appendChild(document.createTextNode("You have loaded an area which contains " + browseFeatureList.length + " features. In general, some browsers may not cope well with displaying this quantity of data. Generally, browsers work best at displaying less than 100 features at a time: doing anything else may make your browser slow/unresponsive. If you are sure you want to display this data, you may do so by clicking the button below."));
 135     div.appendChild(p);
 136
 137     var input = document.createElement("input");
 138     input.type = "submit";
 139     input.value = "Load Data";
 140     input.onclick = loadFeatureList;
 141     div.appendChild(input);
 142
 143     $("browse_object_list").innerHTML = "";
 144     $("browse_object_list").appendChild(div);
 145   }
 146
 147   function loadFeatureList() {
 148     browseDataLayer.addFeatures(browseFeatureList);
 149     browseDataLayer.events.triggerEvent("loadend");
 150
 151     browseFeatureList = [];
 152
 153     return false;
 154   }
 155
 156   function customDataLoader(request) {
 157     if (browseActive) {
 158       var doc = request.responseXML;
 159
 160       if (!doc || !doc.documentElement) {
 161         doc = request.responseText;
 162       }
 163
 164       var options = {};
 165
 166       OpenLayers.Util.extend(options, this.formatOptions);
 167
 168       if (this.map && !this.projection.equals(this.map.getProjectionObject())) {
 169         options.externalProjection = this.projection;
 170         options.internalProjection = this.map.getProjectionObject();
 171       }
 172
 173       var gml = this.format ? new this.format(options) : new OpenLayers.Format.GML(options);
 174
 175       browseFeatureList = gml.read(doc);
 176
 177       if (!this.maxFeatures || browseFeatureList.length <= this.maxFeatures) {
 178         loadFeatureList();
 179       } else {
 180         displayFeatureWarning();
 181       }
 182     }
 183   }
 184
 185   function getData(bounds) {
 186     var projected = bounds.clone().transform(new OpenLayers.Projection("EPSG:900913"), new OpenLayers.Projection("EPSG:4326"));
 187     var size = projected.getWidth() * projected.getHeight();
 188
 189     if (size > 0.25) {
 190       $("browse_status").innerHTML = "Unable to load: Bounding box size of " + size + " is too large. (Must be smaller than 0.25)<br />";
 191     } else {
 192       loadGML("/api/0.5/map?bbox=" + projected.toBBOX());
 193     }
 194   }
 195
 196   function loadGML(url) {
 197     $("browse_status").innerHTML = "Loading...";
 198     $("browse_object_list").innerHTML = "";
 199
 200     if (!browseDataLayer) {
 201       var style = new OpenLayers.Style();
 202
 203       style.addRules([new OpenLayers.Rule({
 204         symbolizer: {
 205           Polygon: { fillColor: '#ff0000', strokeColor: '#ff0000' },
 206           Line: { fillColor: '#ffff00', strokeColor: '#000000', strokeOpacity: '0.4' },
 207           Point: { fillColor: '#00ff00', strokeColor: '#00ff00' }
 208         }
 209       })]);
 210
 211       browseDataLayer = new OpenLayers.Layer.GML("Data", url, {
 212         format: OpenLayers.Format.OSM,
 213         formatOptions: { checkTags: true },
 214         maxFeatures: 100,
 215         requestSuccess: customDataLoader,
 216         displayInLayerSwitcher: false,
 217         styleMap: new OpenLayers.StyleMap({
 218           default: style,
 219           select: { strokeColor: '#0000ff', strokeWidth: 8 }
 220         })
 221       });
 222       browseDataLayer.events.register("loadend", browseDataLayer, dataLoaded );
 223       map.addLayer(browseDataLayer);
 224
 225       browseSelectControl = new OpenLayers.Control.SelectFeature(browseDataLayer, { onSelect: onFeatureSelect });
 226       browseSelectControl.handler.stopDown = false;
 227       browseSelectControl.handler.stopUp = false;
 228       map.addControl(browseSelectControl);
 229       browseSelectControl.activate();
 230     } else {
 231       browseDataLayer.setUrl(url);
 232     }
 233
 234     browseActiveFeature = null;
 235   }
 236
 237   function dataLoaded() {
 238     if (browseActive) {
 239       $("browse_status").innerHTML = "Loaded."
 240
 241       var list = document.createElement("ul");
 242
 243       for (var i = 0; i < this.features.length; i++) {
 244         var feature = this.features[i];
 245
 246         // Type, for linking
 247         var type = "way";
 248         if (feature.geometry.CLASS_NAME == "OpenLayers.Geometry.Point") {
 249           type = "node";
 250         }
 251         var typeName = type.substr(0,1).toUpperCase() + type.substr(1,type.length);
 252         var li = document.createElement("li");
 253         li.appendChild(document.createTextNode(typeName + " "));
 254
 255         // Link, for viewing in the tab
 256         var link = document.createElement("a");
 257         link.href =  "/browse/" + type + "/" + feature.osm_id;
 258         var name = feature.attributes.name || feature.osm_id;
 259         link.appendChild(document.createTextNode(name));
 260         link.feature = feature;
 261         link.onclick = OpenLayers.Function.bind(viewFeatureLink, link);
 262         li.appendChild(link);
 263
 264         list.appendChild(li);
 265       }
 266
 267       browseObjectList = document.createElement("div")
 268       browseObjectList.appendChild(list)
 269
 270       var link = document.createElement("a");
 271       link.href = this.url;
 272       link.appendChild(document.createTextNode("API"));
 273       browseObjectList.appendChild(link);
 274
 275       $("browse_object_list").innerHTML = "";
 276       $("browse_object_list").appendChild(browseObjectList);
 277     }
 278   }
 279
 280   function viewFeatureLink() {
 281     var layer = this.feature.layer;
 282
 283     for (var i = 0; i < layer.selectedFeatures.length; i++) {
 284       var f = layer.selectedFeatures[i];
 285       layer.drawFeature(f, layer.styleMap.createSymbolizer(f, "default"));
 286     }
 287
 288     onFeatureSelect(this.feature);
 289
 290     if (browseMode != "auto") {
 291       map.setCenter(this.feature.geometry.getBounds().getCenterLonLat());
 292     }
 293
 294     return false;
 295   }
 296
 297   function loadObjectList() {
 298     $("browse_object_list").innerHTML="";
 299     $("browse_object_list").appendChild(browseObjectList);
 300
 301     return false;
 302   }
 303
 304   function onFeatureSelect(feature) {
 305     // Unselect previously selected feature
 306     if (browseActiveFeature) {
 307       browseActiveFeature.layer.drawFeature(
 308         browseActiveFeature,
 309         browseActiveFeature.layer.styleMap.createSymbolizer(browseActiveFeature, "default")
 310       );
 311     }
 312
 313     // Redraw in selected style
 314     feature.layer.drawFeature(
 315       feature, feature.layer.styleMap.createSymbolizer(feature, "select")
 316     );
 317
 318     // If the current object is the list, don't innerHTML="", since that could clear it.
 319     if ($("browse_object_list").firstChild == browseObjectList) {
 320       $("browse_object_list").removeChild(browseObjectList);
 321     } else {
 322       $("browse_object_list").innerHTML = "";
 323     }
 324
 325     // Create a link back to the object list
 326     var link = document.createElement("a");
 327     link.href = "#";
 328     link.onclick = loadObjectList;
 329     link.appendChild(document.createTextNode("Back to Object List"));
 330
 331     var div = document.createElement("div");
 332     div.appendChild(link)
 333
 334     $("browse_object_list").appendChild(div);
 335
 336     var type = "way";
 337     if (feature.geometry.CLASS_NAME == "OpenLayers.Geometry.Point") {
 338         type = "node";
 339     }
 340
 341     var link = document.createElement("a");
 342     link.href = "/browse/" + type + "/" + feature.osm_id;
 343     link.appendChild(document.createTextNode("Database entry for " + feature.osm_id));
 344
 345     var div = document.createElement("div");
 346     div.style.marginTop = "20px"
 347     div.appendChild(link);
 348
 349     $("browse_object_list").appendChild(div);
 350
 351     // Now the list of attributes
 352     var ul = document.createElement("ul");
 353     for (var key in feature.attributes) {
 354       var li = document.createElement("li");
 355       var b = document.createElement("b");
 356       b.appendChild(document.createTextNode(key));
 357       li.appendChild(b);
 358       li.appendChild(document.createTextNode(": " + feature.attributes[key]));
 359       ul.appendChild(li);
 360     }
 361
 362     $("browse_object_list").appendChild(ul);
 363
 364     var link = document.createElement("a");
 365     link.href =  "/browse/"+type+"/"+feature.osm_id+"/history";
 366     link.appendChild(document.createTextNode("History"));
 367     link.onclick = OpenLayers.Function.bind(loadHistory, {
 368       type: type, feature: feature, link: link
 369     });
 370
 371     $("browse_object_list").appendChild(link);
 372
 373     // Stash the currently drawn feature
 374     browseActiveFeature = feature;
 375   }
 376
 377   function loadHistory() {
 378     this.link.href = "";
 379     this.link.innerHTML = "Wait...";
 380
 381     new Ajax.Request("/api/0.5/" + this.type + "/" + this.feature.osm_id + "/history", {
 382       onComplete: OpenLayers.Function.bind(displayHistory, this)
 383     });
 384
 385     return false;
 386   }
 387
 388   function displayHistory(request) {
 389     if (browseActiveFeature.osm_id != this.feature.osm_id || $("browse_object_list").firstChild == browseObjectList)  {
 390         return false;
 391     }
 392
 393     this.link.parentNode.removeChild(this.link);
 394
 395     var doc = request.responseXML;
 396     var div = document.createElement("div");
 397     var h3 = document.createElement("h3");
 398     h3.appendChild(document.createTextNode("History"));
 399     div.appendChild(h3);
 400
 401     var nodes = doc.getElementsByTagName(this.type);
 402     var history = document.createElement("ul");
 403     for (var i = nodes.length - 1; i >= 0; i--) {
 404       var user = nodes[i].getAttribute("user") || "private user";
 405       var timestamp = nodes[i].getAttribute("timestamp");
 406       var item = document.createElement("li");
 407       item.appendChild(document.createTextNode("Edited by " + user + " at " + timestamp));
 408       history.appendChild(item);
 409     }
 410     div.appendChild(history);
 411
 412     var link = document.createElement("a");
 413     link.appendChild(document.createTextNode("History entry for " + this.feature.osm_id));
 414     link.href = "/browse/"+this.type+"/"+this.feature.osm_id+"/history";
 415     div.appendChild(link);
 416
 417     $("browse_object_list").appendChild(div);
 418   }
 419
 420   startBrowse();
 421 EOJ