package nl.tudelft.goal.ut2004.visualizer.timeline.map;
   
   import java.awt.Point;
   import java.awt.event.InputEvent;
   import java.awt.event.MouseEvent;
   import java.awt.event.MouseListener;
   import java.awt.event.MouseMotionListener;
   
   import javax.swing.event.MouseInputAdapter;
  
  import nl.tudelft.goal.ut2004.visualizer.map.MapGLPanel;
  
  
  import cz.cuni.amis.pogamut.base3d.worldview.object.Location;
  
  /**
   * Class for controling viewport in map.
   * <p>
   * The view of map is specified in {@link MapViewpoint}, it consists from
   * <ul>
   *  <li>center point - the point in worldspace at which the eye is looking at</li>
   *  <li>eye point - the worldspace point from which is player looking at the center point</li>
   *  <li>up vector - determines which direction is up, in worldspace</li>
   * </ul>
   * These three components are always orthogonal (the angle between them is 90 degrees).
   * <p>
   * The user is controlling the view by dragging the mouse while pressing the buttons:
   * <ul>
   *  <li>Left button - deltaX will move your view angle to left or right,
   *      deltaY will move you forward or backward (no change in height)</li>
   *  <li>Right button - freely change the direction at which you are looking. </li>
   *  <li>Left and right button - change position while maintaining the view vector.
   *      deltaX - left or right, deltaY up or down.</li>
   *  <li>Triple click anywhere will turn your view to the origin (0,0,0), where map usually is</li>
   * </ul>
   * X axis is green,
   * Y axis is red
   * Z axis is up/down (up direction is negative)
   *
   * @author Honza
   */
  public class MapController extends MouseInputAdapter implements MouseListener, MouseMotionListener {
  
      final private MapGLPanel panel;
      final private MapViewpoint viewpoint;
      private Point last;
  
      private Location center;
  
      /**
       * Robot for keeping cursor at one place during dragging (otherwise drag is limited by screen space)
       */
      java.awt.Robot robot;
  
      public MapController(MapGLPanel panel, MapViewpoint mapViewpoint, Location center) {
          this.panel = panel;
          this.viewpoint = mapViewpoint;
          this.center = new Location(center);
      }
  
      public void registerListeners() {
          panel.addMouseListener(this);
          panel.addMouseMotionListener(this);
          panel.addMouseWheelListener(this);
      }
  
      public void unregisterListeners() {
          panel.removeMouseListener(this);
          panel.removeMouseMotionListener(this);
          panel.removeMouseWheelListener(this);
      }
  
      @Override
      public void mouseClicked(MouseEvent e) {
          if (e.getClickCount() == 3) {
              viewpoint.lookAt(center, 2, false);
          }
      }
  
      
  
      @Override
      public void mousePressed(MouseEvent e) {
          updateMode(e);
          last = e.getLocationOnScreen();
      }
  
      @Override
      public void mouseReleased(MouseEvent e) {
          updateMode(e);
          last = e.getLocationOnScreen();
      }
  
      private ModificationStatus updateMode(MouseEvent e) {
          boolean leftDown = (e.getModifiersEx() & InputEvent.BUTTON1_DOWN_MASK) == InputEvent.BUTTON1_DOWN_MASK;
          boolean rightDown = (e.getModifiersEx() & InputEvent.BUTTON3_DOWN_MASK) == InputEvent.BUTTON3_DOWN_MASK;
  
          if (leftDown && rightDown) {
              operationMode = ModificationStatus.MOVE_CENTER;
         } else if (leftDown && !rightDown) {
             operationMode = ModificationStatus.MOVE_AHEAD;
         } else if (!leftDown && rightDown) {
             operationMode = ModificationStatus.ROTATE_EYE;
         } else {
             operationMode = ModificationStatus.NONE;
         }
         System.out.println("ModificationMode: " + operationMode);
         return operationMode;
     }
 
     private void changeViewpoint(double deltaX, double deltaY) {
         // how many pixels are necessary to move one degree
         double pixelsPerDegree = 5;
         // how many ut units is one pixel
         double unitsPerPixel = 10;
         switch (operationMode) {
             case ROTATE_EYE:
                 rotateEye((deltaX) / pixelsPerDegree, (deltaY) / pixelsPerDegree);
                 break;
             case MOVE_CENTER:
                 moveCenter(deltaX * unitsPerPixel, (deltaY) * unitsPerPixel);
                 break;
             case MOVE_AHEAD:
                 moveAhead(deltaY * unitsPerPixel, deltaX / pixelsPerDegree);
                 break;
         }
     }
 
     private void moveAhead(double distance, double angle) {
         Location forward = viewpoint.getEye2Center().getNormalized().scale(-distance);
         forward = forward.setZ(0);
         viewpoint.move(forward);
         viewpoint.rotateCenter(new Location(0, 0, 1), angle);
     }
 
     @Override
     public void mouseDragged(MouseEvent e) {
         Point current = e.getLocationOnScreen();
 
         int deltaX = current.x - last.x;
         int deltaY = current.y - last.y;
 
         changeViewpoint(deltaX, deltaY);
 
         unregisterListeners();
         //robot.mouseMove(last.x, last.y);
         registerListeners();
 
         last = current;
     }
 
     /**
      * Rotate eye according to the delta move by mouse or other pointer.
      * <p>
      * @param leftRightAngle how many degrees should I turn to left or right
      * @param upDownAngle how many degrees should I move my "viewangle" up or down
      */
     private void rotateEye(double leftRightAngle, double upDownAngle) {
         // rotate up/down
         viewpoint.rotateCenter(viewpoint.getRightVector(), upDownAngle);
 
         // rotate left/right
         viewpoint.rotateCenter(new Location(0, 0, 1), leftRightAngle);
     }
 
     private void moveCenter(double deltaX, double deltaY) {
         // horizontal movement
         Location right = viewpoint.getRightVector().getNormalized().scale(-deltaX);
         viewpoint.move(right);
 
         // vertical movement
         Location up = new Location(0, 0, deltaY);
         System.out.println("MoveCenter up " + up);
         viewpoint.move(up);
     }
 
     private enum ModificationStatus {
 
         NONE,
         /** look around, only 180 degrees */
         ROTATE_EYE,
         /** move center up/down and left/right     */
         MOVE_CENTER,
         /** move ahead and turn */
         MOVE_AHEAD,
     }
     private ModificationStatus operationMode = ModificationStatus.NONE;
 }