Fixing Geolocation on Firefox

tools/dom/templates/html/impl/impl_Geolocation.darttemplate

+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of $LIBRARYNAME;
+
+@DocsEditable
+$(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+
+  @DomName('Geolocation.getCurrentPosition')
+  Future<Geoposition> getCurrentPosition({bool enableHighAccuracy,
+      Duration timeout, Duration maximumAge}) {
+    var options = {};
+    if (enableHighAccuracy != null) {
+      options['enableHighAccuracy'] = enableHighAccuracy;
+    }
+    if (timeout != null) {
+      options['timeout'] = timeout.inMilliseconds;
+    }
+    if (maximumAge != null) {
+      options['maximumAge'] = maximumAge.inMilliseconds;
+    }
+    var completer = new Completer<Geoposition>();
+    try {
+      $dom_getCurrentPosition(
+          (position) {
+            completer.complete(_ensurePosition(position));
+          },
+          (error) {
+            completer.completeError(error);
+          },
+          options);
+    } catch (e, stacktrace) {
+      completer.completeError(e, stacktrace);
+    }
+    return completer.future;
+  }
+
+  @DomName('Geolocation.watchPosition')
+  Stream<Geoposition> watchPosition({bool enableHighAccuracy,
+      Duration timeout, Duration maximumAge}) {
+
+    var options = {};
+    if (enableHighAccuracy != null) {
+      options['enableHighAccuracy'] = enableHighAccuracy;
+    }
+    if (timeout != null) {
+      options['timeout'] = timeout.inMilliseconds;
+    }
+    if (maximumAge != null) {
+      options['maximumAge'] = maximumAge.inMilliseconds;
+    }
+
+    int watchId;
+    var controller;
+    controller = new StreamController<Geoposition>(
+      onSubscriptionStateChange: () {
+        if (controller.hasSubscribers) {
+          assert(watchId == null);
+          watchId = $dom_watchPosition(
+              (position) {
+                controller.add(_ensurePosition(position));
+              },
+              (error) {
+                controller.signalError(error);
+              },
+              options);
+        } else {
+          assert(watchId != null);
+          $dom_clearWatch(watchId);
+        }
+      });
+
+    return controller.stream;
+  }
+
+  Geoposition _ensurePosition(domPosition) {
+    try {
+      // Firefox may throw on this.
+      if (domPosition is Geoposition) {
+        return domPosition;
+      }
+    } catch(e) {}
+    return new _GeopositionWrapper(domPosition);
+  }
+$!MEMBERS}
+
+$if DART2JS
+/**
+ * Wrapper for FireFox- it returns an object which we cannot map correctly.

[Emily Fortuna, 2013/02/19 19:53:00]

nit: "Firefox"

+ * Basically FireFox was returning a [xpconnect wrapped nsIDOMGeoPosition] but
+ * which has further oddities.
+ */
+class _GeopositionWrapper implements Geoposition {
+  var _ptr;
+  _GeopositionWrapper(this._ptr);
+
+  Coordinates get coords => JS('Coordinates', '#.coords', _ptr);
+  int get timestamp => JS('int', '#.timestamp', _ptr);
+}
+$endif
+
+