// Copyright (c) 1996-98 The Regents of the University of California. All
// Rights Reserved. Permission to use, copy, modify, and distribute this
// software and its documentation for educational, research and non-profit
// purposes, without fee, and without a written agreement is hereby granted,
// provided that the above copyright notice and this paragraph appear in all
// copies. Permission to incorporate this software into commercial products may
// be obtained by contacting the University of California. David F. Redmiles
// Department of Information and Computer Science (ICS) University of
// California Irvine, California 92697-3425 Phone: 714-824-3823. This software
// program and documentation are copyrighted by The Regents of the University
// of California. The software program and documentation are supplied "as is",
// without any accompanying services from The Regents. The Regents do not
// warrant that the operation of the program will be uninterrupted or
// error-free. The end-user understands that the program was developed for
// research purposes and is advised not to rely exclusively on the program for
// any reason. IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY
// PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
// INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
// DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY
// DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
// SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
// CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
// ENHANCEMENTS, OR MODIFICATIONS.

// File: ModeCreateFigPoly.java
// Classes: ModeCreateFigPoly
// Original Author: jrobbins@ics.uci.edu
// $Id: ModeCreateFigPoly.java,v 1.10 1997/06/10 23:43:08 jrobbins Exp $

package uci.graphedit;

import java.awt.*;

/** A Mode to interpert user input while creating a FigPoly. All of
 *  the actual event handling is inherited from ModeCreate. This class
 *  just implements the differences needed to make it specific to
 *  Polys.
 *  <A HREF="../features.html#basic_shapes_polygon">
 *  <TT>FEATURE: basic_shapes_polygon</TT></A>
 */

public class ModeCreateFigPoly extends ModeCreate {
  ////////////////////////////////////////////////////////////////
  // instance variables
  public static final int GRIP_SIZE = 4;

  protected int _npoints = 0;
  protected int _lastX, _lastY, _startX, _startY;
  protected Handle _handle = new Handle(-1);

  ////////////////////////////////////////////////////////////////
  // Mode API
  public String instructions() {
    return "Click to add a point; Double-click to finish";
  }

  ////////////////////////////////////////////////////////////////
  // ModeCreate API

  /** Create a new FigRect instance based on the given mouse down
   * event and the state of the parent Editor. */
  public DiagramElement createNewItem(Event e, int snapX, int snapY) {
    FigPoly p = new FigPoly(snapX, snapY, parent.graphAttrs());
    p.addPoint(snapX, snapY); // add the first point twice
    _startX = _lastX = snapX; _startY = _lastY = snapY;
    _npoints = 2;
    return p;
  }

  ////////////////////////////////////////////////////////////////
  // Event handlers

  public boolean mouseDown(Event e, int x, int y) {
    if (_npoints == 0) return super.mouseDown(e, x, y);
    if (!nearLast(x, y)) {
      parent.damaged(newItem);
      Point snapPt = new Point(x, y);
      parent.snap(snapPt);
      ((FigPoly)newItem).addPoint(snapPt.x, snapPt.y);
      _npoints++;
      parent.damaged(newItem);
    }
    return true;
  }

  public boolean mouseUp(Event e, int x, int y) {
    if (_npoints > 2 && nearLast(x, y)) {
      FigPoly p = (FigPoly) newItem;
      parent.damaged(newItem);
      _handle.index = p.npoints() - 1;
      p.moveVertex(_handle, _startX, _startY, true);
      _npoints = 0;
      parent.damaged(p);
      parent.add(p);
      parent.selectItem(p);
      newItem = null;
      done();
      return true;
    }
    _lastX = x; _lastY = y;
    return true;
  }

  public boolean mouseMove(Event e, int x, int y) {
    return mouseDrag(e, x, y);
  }

  public boolean mouseDrag(Event e, int x, int y) {
    if (_npoints == 0) return false;
    FigPoly p = (FigPoly)newItem;
    parent.damaged(newItem); // startTrans?
    Point snapPt = new Point(x, y);
    parent.snap(snapPt);
    _handle.index = p.npoints() - 1;
    p.moveVertex(_handle, snapPt.x, snapPt.y, true);
    parent.damaged(newItem); // endTrans?
    return true;
  }

  /** Internal function to see if the user clicked twice on the same spot. */
  protected boolean nearLast(int x, int y) {
    return x > _lastX - GRIP_SIZE &&
      x < _lastX + GRIP_SIZE &&
      y > _lastY - GRIP_SIZE &&
      y < _lastY + GRIP_SIZE;
  }

} /* end class ModeCreateFigPoly */