Dart - JS

ex.dart

import "dart:js" as js;
import "dart:mirrors" as mirrors;

class JsProxy {
  js.JsObject $js;

  /// Creates the underlying JavaScript object from the [ctorFqn] and a list of [args]
  JsProxy.proxy([String ctorFqn, List args = const []])
      : this.proxyJsObj(
          ctorFqn == null ?
            js.context['Object'] :
            ctorFqn.split('.').fold(js.context, (p, n) => p[n]),
          args);

  /// Creates the underlying Javascript object from a [jsObject] and a list of [args]
  JsProxy.proxyJsObj([js.JsObject jsObject, List args = const[]]) {
    if (jsObject == null) jsObject = js.context['Object'];
    var jsArgs = new js.JsObject.jsify(args.map(_toJs));
    $js = new js.JsObject(jsObject, jsArgs);
  }

  JsProxy._(this.$js);

  /// Initializes the instance from an existing [jsObject]
  factory JsProxy.fromJsObject(js.JsObject jsObject) =>
      jsObject == null ? null : new JsProxy._(jsObject);

  /// Recursively converts [JsProxy] to their underlying [JsObject]
  dynamic _toJs(dart) {
    if (dart is Iterable) {
      return (dart as Iterable).map(_toJs);
    }

    if (dart is Map) {
      (dart as Map).keys.forEach((k) => dart[k] = _toJs(dart[k]));
      return dart;
    }

    if (dart is JsProxy) {
      return (dart as JsProxy).$js;
    }

    return dart;
  }

  // Helper for generated getters, setters and methods
  void $set(String key, value) {
    $js[key] = _toJs(value);
  }

  dynamic $get(String key) {
    // todo fromJsObject() if returns a JsProxy
    return $js[key];
  }

  dynamic $call(String method, [List args = const[]]) {
    // todo fromJsObject() if returns a JsProxy
    var jsArgs = new js.JsObject.jsify(args.map(_toJs));
    return $js.callMethod(method, jsArgs);
  }

  noSuchMethod(Invocation invocation) {
    var pArgs = invocation.positionalArguments;
    var field = mirrors.MirrorSystem.getName(invocation.memberName);
    if (invocation.isGetter) {
      return $js[field];
    }
    if (invocation.isSetter) {
      field = field.substring(0, field.length - 1);
      return $js[field] = _toJs(pArgs[0]);
    }
    if (invocation.isMethod) {
      var returnType;
      mirrors.reflect(this).type.metadata.forEach((m) {
        if (m.type.isSubtypeOf(mirrors.reflectType(ProxyMethod)) &&
            m.reflectee.name == field) {
            print('match $field');
        }
      });

      print('--match $field');
      if (returnType is JsProxy) print('ret JsProxy');

      var ret = $call(field, pArgs);
      print('match $field');


    }
   throw new UnimplementedError(field);
  }
}

class ProxyMethod {
  final Type returnType;
  final String name;
  final List<Type> arguments;
  const ProxyMethod(this.returnType, this.name, this.arguments);
}


class OlMap extends JsProxy {
  OlMap(Map options): super.proxy('ol.Map', [options]);

  View2d getView() => jsMethod(View2d, 'getView', []);

  void setView(View view) => jsMethod(null, 'setView', [view]);

  jsMethod(List args) {
  }
}


class Tile extends JsProxy {
  Tile(Map options): super.proxy('ol.layer.Tile', [options]);
}

class MapQuest extends JsProxy {
  MapQuest(Map options): super.proxy('ol.source.MapQuest', [options]);
}

class View2d extends JsProxy {
  factory View2d.fromJsObject(jsObject) = JsProxy.fromJsObject;
  View2d(Map options): super.proxy('ol.View2D', [options]);


}


void main() {
  var center = [0, 0];
  var center2 = [4164462.1505763642, 985738.7965919955];

  var mq = new MapQuest({'layer': 'sat'});
  var tile = new Tile({'source': mq});
  var view = new View2d({'center': center, 'zoom': 4});

  var map = new OlMap({
      'target': 'map',
      'layers': [tile],
      'view': view
  });

  print('map view: ${map.getView()}');

  var view2 = new View2d.fromJsObject(map.$call('getView'));

  view2.$call('setCenter', [center2]);
}