/*
Copyright 2011-2016 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.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.states;

import com.google.common.base.Preconditions;
import com.google.security.zynamics.zylib.gui.zygraph.editmode.CStateChange;
import com.google.security.zynamics.zylib.gui.zygraph.editmode.IMouseState;
import com.google.security.zynamics.zylib.gui.zygraph.editmode.IMouseStateChange;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.AbstractZyGraph;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.edges.ZyGraphEdge;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.CStateFactory;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.helpers.CMousePressedHandler;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.transformations.CHitBendsTransformer;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.transformations.CHitEdgeLabelsTransformer;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.transformations.CHitEdgesTransformer;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.editmode.transformations.CHitNodesTransformer;
import com.google.security.zynamics.zylib.yfileswrap.gui.zygraph.nodes.ZyGraphNode;

import y.view.EdgeLabel;
import y.view.HitInfo;

import java.awt.event.MouseEvent;

public class CEdgeLabelExitState<NodeType extends ZyGraphNode<?>, EdgeType extends ZyGraphEdge<?, ?, ?>>
    implements IMouseState {
  /**
   * State factory that creates new state objects when necessary.
   */
  private final CStateFactory<NodeType, EdgeType> m_factory;

  /**
   * The graph the entered node belongs to.
   */
  private final AbstractZyGraph<NodeType, EdgeType> m_graph;

  /**
   * The entered label.
   */
  private final EdgeLabel m_label;

  /**
   * Creates a new state object.
   * 
   * @param factory a CStateFactory that creates new state objects when necessary.
   * @param graph the graph the entered node belongs to
   * @param label the associated egde label
   */
  public CEdgeLabelExitState(final CStateFactory<NodeType, EdgeType> factory,
      final AbstractZyGraph<NodeType, EdgeType> graph, final EdgeLabel label) {
    m_factory = Preconditions.checkNotNull(factory, "Error: factory argument can not be null");
    m_graph = Preconditions.checkNotNull(graph, "Error: graph argument can not be null");
    m_label = Preconditions.checkNotNull(label, "Error: label argument can not be null");
  }

  /**
   * Returns the graph the exited edge label belongs to.
   * 
   * @return The graph the exited edge label belongs to.
   */
  public AbstractZyGraph<NodeType, EdgeType> getGraph() {
    return m_graph;
  }

  public EdgeLabel getLabel() {
    return m_label;
  }

  @Override
  public CStateFactory<NodeType, EdgeType> getStateFactory() {
    return m_factory;
  }

  @Override
  public IMouseStateChange mouseDragged(final MouseEvent event, final AbstractZyGraph<?, ?> graph) {
    return new CStateChange(m_factory.createDefaultState(), true);
  }

  @Override
  public IMouseStateChange mouseMoved(final MouseEvent event, final AbstractZyGraph<?, ?> graph) {
    final double x = m_graph.getEditMode().translateX(event.getX());
    final double y = m_graph.getEditMode().translateY(event.getY());

    final HitInfo hitInfo = m_graph.getGraph().getHitInfo(x, y);

    if (hitInfo.hasHitNodes()) {
      return CHitNodesTransformer.enterNode(m_factory, event, hitInfo);
    } else if (hitInfo.hasHitNodeLabels()) {
      throw new IllegalStateException();
    } else if (hitInfo.hasHitEdges()) {
      return CHitEdgesTransformer.enterEdge(m_factory, event, hitInfo);
    } else if (hitInfo.hasHitEdgeLabels()) {
      return CHitEdgeLabelsTransformer.enterEdgeLabel(m_factory, event, hitInfo);
    } else if (hitInfo.hasHitBends()) {
      return CHitBendsTransformer.enterBend(m_factory, event, hitInfo);
    } else if (hitInfo.hasHitPorts()) {
      return new CStateChange(this, true);
    } else {
      // We are in the exit state. All GUI changes have been undone and once
      // again we are not hitting anything. That means we can now return to
      // the default state.

      return new CStateChange(m_factory.createDefaultState(), true);
    }
  }

  @Override
  public IMouseStateChange mousePressed(final MouseEvent event, final AbstractZyGraph<?, ?> graph) {
    return CMousePressedHandler.handleMousePressed(m_factory, this, graph, event);
  }

  @Override
  public IMouseStateChange mouseReleased(final MouseEvent event, final AbstractZyGraph<?, ?> graph) {
    return new CStateChange(m_factory.createDefaultState(), true);
  }

}
