app/views/browse/start.rjs

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