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     browseActive = true;
  19
  20     openSidebar({ onclose: stopBrowse });
  21
  22     var vectors = new OpenLayers.Layer.Vector();
  23
  24     browseBoxControl = new OpenLayers.Control.DrawFeature(vectors, OpenLayers.Handler.RegularPolygon, {
  25       handlerOptions: {
  26         sides: 4,
  27         snapAngle: 90,
  28         irregular: true,
  29         persist: true,
  30         callbacks: { done: endDrag }
  31       }
  32     });
  33     map.addControl(browseBoxControl);
  34
  35     map.events.register("moveend", map, showData);
  36     map.events.triggerEvent("moveend");
  37   }
  38
  39   function showData() {
  40     if (browseMode == "auto") {
  41       if (map.getZoom() >= 15) {
  42           useMap();
  43       } else {
  44           setStatus("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 (browseSelectControl) {
  54         browseSelectControl.destroy();
  55         browseSelectControl = null;
  56       }
  57
  58       if (browseBoxControl) {
  59         browseBoxControl.destroy();
  60         browseBoxControl = null;
  61       }
  62
  63       if (browseActiveFeature) {
  64         browseActiveFeature.destroy();
  65         browseActiveFeature = null;
  66       }
  67
  68       if (browseDataLayer) {
  69         browseDataLayer.destroy();
  70         browseDataLayer = 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     clearStatus();
 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_content").innerHTML = "";
 144     $("browse_content").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       setStatus("Unable to load: Bounding box size of " + size + " is too large (must be smaller than 0.25)");
 191     } else {
 192       loadGML("/api/#{API_VERSION}/map?bbox=" + projected.toBBOX());
 193     }
 194   }
 195
 196   function loadGML(url) {
 197     setStatus("Loading...");
 198     $("browse_content").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: {
 214           checkTags: true,
 215           interestingTagsExclude: ['source','source_ref','source:ref','history','attribution','created_by','tiger:county','tiger:tlid','tiger:upload_uuid']
 216         },
 217         maxFeatures: 100,
 218         requestSuccess: customDataLoader,
 219         displayInLayerSwitcher: false,
 220         styleMap: new OpenLayers.StyleMap({
 221           'default': style,
 222           'select': { strokeColor: '#0000ff', strokeWidth: 8 }
 223         })
 224       });
 225       browseDataLayer.events.register("loadend", browseDataLayer, dataLoaded );
 226       map.addLayer(browseDataLayer);
 227
 228       browseSelectControl = new OpenLayers.Control.SelectFeature(browseDataLayer, { onSelect: onFeatureSelect });
 229       browseSelectControl.handlers.feature.stopDown = false;
 230       browseSelectControl.handlers.feature.stopUp = false;
 231       map.addControl(browseSelectControl);
 232       browseSelectControl.activate();
 233     } else {
 234       browseDataLayer.setUrl(url);
 235     }
 236
 237     browseActiveFeature = null;
 238   }
 239
 240   function dataLoaded() {
 241     if (browseActive) {
 242       clearStatus();
 243
 244       browseObjectList = document.createElement("div")
 245
 246       var heading = document.createElement("p");
 247       heading.className = "browse_heading";
 248       heading.appendChild(document.createTextNode("Object list"));
 249       browseObjectList.appendChild(heading);
 250
 251       var list = document.createElement("ul");
 252
 253       for (var i = 0; i < this.features.length; i++) {
 254         var feature = this.features[i];
 255
 256         // Type, for linking
 257         var type = featureType(feature);
 258         var typeName = ucFirst(type);
 259         var li = document.createElement("li");
 260         li.appendChild(document.createTextNode(typeName + " "));
 261
 262         // Link, for viewing in the tab
 263         var link = document.createElement("a");
 264         link.href =  "/browse/" + type + "/" + feature.osm_id;
 265         var name = feature.attributes.name || feature.osm_id;
 266         link.appendChild(document.createTextNode(name));
 267         link.feature = feature;
 268         link.onclick = OpenLayers.Function.bind(viewFeatureLink, link);
 269         li.appendChild(link);
 270
 271         list.appendChild(li);
 272       }
 273
 274       browseObjectList.appendChild(list)
 275
 276       var link = document.createElement("a");
 277       link.href = this.url;
 278       link.appendChild(document.createTextNode("API"));
 279       browseObjectList.appendChild(link);
 280
 281       $("browse_content").innerHTML = "";
 282       $("browse_content").appendChild(browseObjectList);
 283     }
 284   }
 285
 286   function viewFeatureLink() {
 287     var layer = this.feature.layer;
 288
 289     for (var i = 0; i < layer.selectedFeatures.length; i++) {
 290       var f = layer.selectedFeatures[i];
 291       layer.drawFeature(f, layer.styleMap.createSymbolizer(f, "default"));
 292     }
 293
 294     onFeatureSelect(this.feature);
 295
 296     if (browseMode != "auto") {
 297       map.setCenter(this.feature.geometry.getBounds().getCenterLonLat());
 298     }
 299
 300     return false;
 301   }
 302
 303   function loadObjectList() {
 304     $("browse_content").innerHTML="";
 305     $("browse_content").appendChild(browseObjectList);
 306
 307     return false;
 308   }
 309
 310   function onFeatureSelect(feature) {
 311     // Unselect previously selected feature
 312     if (browseActiveFeature) {
 313       browseActiveFeature.layer.drawFeature(
 314         browseActiveFeature,
 315         browseActiveFeature.layer.styleMap.createSymbolizer(browseActiveFeature, "default")
 316       );
 317     }
 318
 319     // Redraw in selected style
 320     feature.layer.drawFeature(
 321       feature, feature.layer.styleMap.createSymbolizer(feature, "select")
 322     );
 323
 324     // If the current object is the list, don't innerHTML="", since that could clear it.
 325     if ($("browse_content").firstChild == browseObjectList) {
 326       $("browse_content").removeChild(browseObjectList);
 327     } else {
 328       $("browse_content").innerHTML = "";
 329     }
 330
 331     // Create a link back to the object list
 332     var div = document.createElement("div");
 333     div.style.textAlign = "center";
 334     div.style.marginBottom = "20px";
 335     $("browse_content").appendChild(div);
 336     var link = document.createElement("a");
 337     link.href = "#";
 338     link.onclick = loadObjectList;
 339     link.appendChild(document.createTextNode("Display object list"));
 340     div.appendChild(link);
 341
 342     var table = document.createElement("table");
 343     table.width = "100%";
 344     table.className = "browse_heading";
 345     $("browse_content").appendChild(table);
 346
 347     var tr = document.createElement("tr");
 348     table.appendChild(tr);
 349
 350     var heading = document.createElement("td");
 351     heading.appendChild(document.createTextNode(featureName(feature)));
 352     tr.appendChild(heading);
 353
 354     var td = document.createElement("td");
 355     td.align = "right";
 356     tr.appendChild(td);
 357
 358     var type = featureType(feature);
 359     var link = document.createElement("a");
 360     link.href = "/browse/" + type + "/" + feature.osm_id;
 361     link.appendChild(document.createTextNode("Details"));
 362     td.appendChild(link);
 363
 364     var div = document.createElement("div");
 365     div.className = "browse_details";
 366
 367     $("browse_content").appendChild(div);
 368
 369     // Now the list of attributes
 370     var ul = document.createElement("ul");
 371     for (var key in feature.attributes) {
 372       var li = document.createElement("li");
 373       var b = document.createElement("b");
 374       b.appendChild(document.createTextNode(key));
 375       li.appendChild(b);
 376       li.appendChild(document.createTextNode(": " + feature.attributes[key]));
 377       ul.appendChild(li);
 378     }
 379
 380     div.appendChild(ul);
 381
 382     var link = document.createElement("a");
 383     link.href =  "/browse/" + type + "/" + feature.osm_id + "/history";
 384     link.appendChild(document.createTextNode("Show history"));
 385     link.onclick = OpenLayers.Function.bind(loadHistory, {
 386       type: type, feature: feature, link: link
 387     });
 388
 389     div.appendChild(link);
 390
 391     // Stash the currently drawn feature
 392     browseActiveFeature = feature;
 393   }
 394
 395   function loadHistory() {
 396     this.link.href = "";
 397     this.link.innerHTML = "Wait...";
 398
 399     new Ajax.Request("/api/#{API_VERSION}/" + this.type + "/" + this.feature.osm_id + "/history", {
 400       onComplete: OpenLayers.Function.bind(displayHistory, this)
 401     });
 402
 403     return false;
 404   }
 405
 406   function displayHistory(request) {
 407     if (browseActiveFeature.osm_id != this.feature.osm_id || $("browse_content").firstChild == browseObjectList)  {
 408         return false;
 409     }
 410
 411     this.link.parentNode.removeChild(this.link);
 412
 413     var doc = request.responseXML;
 414
 415     var table = document.createElement("table");
 416     table.width = "100%";
 417     table.className = "browse_heading";
 418     $("browse_content").appendChild(table);
 419
 420     var tr = document.createElement("tr");
 421     table.appendChild(tr);
 422
 423     var heading = document.createElement("td");
 424     heading.appendChild(document.createTextNode("History for " + featureName(this.feature)));
 425     tr.appendChild(heading);
 426
 427     var td = document.createElement("td");
 428     td.align = "right";
 429     tr.appendChild(td);
 430
 431     var link = document.createElement("a");
 432     link.href = "/browse/" + this.type + "/" + this.feature.osm_id + "/history";
 433     link.appendChild(document.createTextNode("Details"));
 434     td.appendChild(link);
 435
 436     var div = document.createElement("div");
 437     div.className = "browse_details";
 438
 439     var nodes = doc.getElementsByTagName(this.type);
 440     var history = document.createElement("ul");
 441     for (var i = nodes.length - 1; i >= 0; i--) {
 442       var user = nodes[i].getAttribute("user") || "private user";
 443       var timestamp = nodes[i].getAttribute("timestamp");
 444       var item = document.createElement("li");
 445       item.appendChild(document.createTextNode("Edited by " + user + " at " + timestamp));
 446       history.appendChild(item);
 447     }
 448     div.appendChild(history);
 449
 450     $("browse_content").appendChild(div);
 451   }
 452
 453   function featureType(feature) {
 454     if (feature.geometry.CLASS_NAME == "OpenLayers.Geometry.Point") {
 455       return "node";
 456     } else {
 457       return "way";
 458     }
 459   }
 460
 461   function featureName(feature) {
 462     if (feature.attributes.name) {
 463       return feature.attributes.name;
 464     } else {
 465       return ucFirst(featureType(feature)) + " " + feature.osm_id;
 466     }
 467   }
 468
 469   function setStatus(status) {
 470     $("browse_status").innerHTML = status;
 471     $("browse_status").style.display = "block";
 472   }
 473
 474   function clearStatus() {
 475     $("browse_status").innerHTML = "";
 476     $("browse_status").style.display = "none";
 477   }
 478
 479   function ucFirst(str) {
 480     return str.substr(0,1).toUpperCase() + str.substr(1,str.length);
 481   }
 482
 483   startBrowse();
 484 EOJ