// Copyright 2012 Google Inc. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.google.collide.client.editor.input;

import org.waveprotocol.wave.client.common.util.SignalEvent;

import com.google.collide.json.shared.JsonArray;
import com.google.collide.shared.util.JsonCollections;

/**
 * Implementation of proxy that delegated execution to a list of executors.
 *
 */
public class RootActionExecutor implements ActionExecutor {

  /**
   * Object used to unregister delegate.
   */
  public class Remover {

    public Remover(ActionExecutor instance) {
      this.instance = instance;
    }

    private ActionExecutor instance;

    public void remove() {
      delegates.remove(instance);
    }
  }

  private final JsonArray<ActionExecutor> delegates = JsonCollections.createArray();

  public Remover addDelegate(ActionExecutor delegate) {
    delegates.add(delegate);
    return new Remover(delegate);
  }

  @Override
  public boolean execute(String actionName, InputScheme scheme, SignalEvent event) {
    for (int i = 0, l = delegates.size(); i < l; i++) {
      if (delegates.get(i).execute(actionName, scheme, event)) {
        return true;
      }
    }
    return false;
  }
}
