DiffEditorSeparator.java

package jetbrains.mps.vcs.diff.ui.common;

/*Generated by MPS */

import javax.swing.JComponent;
import jetbrains.mps.ide.tooltips.TooltipComponent;
import java.util.Map;
import jetbrains.mps.baseLanguage.tuples.runtime.Tuples;
import javax.swing.event.ChangeListener;
import javax.swing.event.ChangeEvent;
import java.awt.Dimension;
import jetbrains.mps.ide.tooltips.MPSToolTipManager;
import jetbrains.mps.internal.collections.runtime.MapSequence;
import java.util.LinkedHashMap;
import jetbrains.mps.internal.collections.runtime.ListSequence;
import jetbrains.mps.baseLanguage.tuples.runtime.MultiTuple;
import jetbrains.mps.smodel.ModelAccess;
import java.util.HashMap;
import jetbrains.mps.internal.collections.runtime.IterableUtils;
import jetbrains.mps.internal.collections.runtime.ISelector;
import jetbrains.mps.vcs.diff.changes.ModelChange;
import java.awt.Graphics;
import jetbrains.mps.internal.collections.runtime.IMapping;
import javax.swing.JViewport;
import java.awt.event.MouseEvent;
import java.awt.Point;
import jetbrains.mps.internal.collections.runtime.IWhereFilter;

public class DiffEditorSeparator extends JComponent implements TooltipComponent {
  private static final int WIDTH = 30;
  private ChangeGroupLayout myChangeGroupLayout;
  private Map<ChangeGroup, Tuples._2<Bounds, Bounds>> myGroupsWithBounds;
  private Map<ChangeGroup, String> myChangeGroupDescriptions;
  public DiffEditorSeparator(ChangeGroupLayout changeGroupLayout) {
    myChangeGroupLayout = changeGroupLayout;
    ChangeListener viewportListener = new ChangeListener() {
      public void stateChanged(ChangeEvent e) {
        invalidateAndRepaint();
      }
    };
    getLeftViewport().addChangeListener(viewportListener);
    getRightViewport().addChangeListener(viewportListener);
    setMinimumSize(new Dimension(WIDTH, 1));
    setPreferredSize(new Dimension(WIDTH, 1));
    myChangeGroupLayout.addInvalidateListener(new ChangeGroupInvalidateListener() {
      public void changeGroupsInvalidated() {
        invalidateAndRepaint();
      }
    });
    MPSToolTipManager.getInstance().registerComponent(this);
  }
  private void ensureBoundsCalculated() {
    if (myGroupsWithBounds != null) {
      return;
    }
    myGroupsWithBounds = MapSequence.fromMap(new LinkedHashMap<ChangeGroup, Tuples._2<Bounds, Bounds>>(16, (float) 0.75, false));
    int leftOffset = getOffset(getLeftViewport());
    int rightOffset = getOffset(getRightViewport());

    for (ChangeGroup group : ListSequence.fromList(myChangeGroupLayout.getChangeGroups())) {
      int leftStart = (int) group.getLeftBounds().start() + leftOffset;
      int leftEnd = (int) group.getLeftBounds().end() + leftOffset;
      int rightStart = (int) group.getRightBounds().start() + rightOffset;
      int rightEnd = (int) group.getRightBounds().end() + rightOffset;
      MapSequence.fromMap(myGroupsWithBounds).put(group, MultiTuple.<Bounds,Bounds>from(new Bounds(leftStart, leftEnd), new Bounds(rightStart, rightEnd)));
    }

    ModelAccess.instance().runReadAction(new Runnable() {
      public void run() {
        myChangeGroupDescriptions = MapSequence.fromMap(new HashMap<ChangeGroup, String>());
        for (ChangeGroup group : ListSequence.fromList(myChangeGroupLayout.getChangeGroups())) {
          MapSequence.fromMap(myChangeGroupDescriptions).put(group, IterableUtils.join(ListSequence.fromList(group.getChanges()).select(new ISelector<ModelChange, String>() {
            public String select(ModelChange ch) {
              return ch.getDescription();
            }
          }), "\n\n"));
        }
      }
    });
  }
  @Override
  protected void paintComponent(Graphics g) {
    synchronized (this) {
      ensureBoundsCalculated();

      for (IMapping<ChangeGroup, Tuples._2<Bounds, Bounds>> groupWithBounds : MapSequence.fromMap(myGroupsWithBounds)) {
        Bounds left = groupWithBounds.value()._0();
        Bounds right = groupWithBounds.value()._1();
        int[] xx = new int[]{0, getWidth(), getWidth(), 0};
        int[] yy = new int[]{(int) left.start(), (int) right.start(), (int) right.end(), (int) left.end()};

        g.setColor(ChangeColors.get(groupWithBounds.key().getChangeType()));
        g.fillPolygon(xx, yy, 4);
        g.setColor(ChangeColors.get(groupWithBounds.key().getChangeType()).darker());
        g.drawLine(0, (int) left.start(), getWidth() - 1, (int) right.start());
        g.drawLine(0, (int) left.end(), getWidth() - 1, (int) right.end());
      }
    }
  }
  private void invalidateAndRepaint() {
    synchronized (this) {
      myGroupsWithBounds = null;
      myChangeGroupDescriptions = null;
    }
    repaint();
  }
  private JViewport getLeftViewport() {
    return myChangeGroupLayout.getLeftComponent().getViewport();
  }
  private JViewport getRightViewport() {
    return myChangeGroupLayout.getRightComponent().getViewport();
  }
  private int getOffset(JViewport viewport) {
    return -viewport.getViewPosition().y + myChangeGroupLayout.getEditorVerticalOffset();
  }
  @Override
  public String getMPSTooltipText(MouseEvent mouseEvent) {
    synchronized (this) {
      ensureBoundsCalculated();
      final Point p = mouseEvent.getPoint();
      IMapping<ChangeGroup, Tuples._2<Bounds, Bounds>> group = MapSequence.fromMap(myGroupsWithBounds).findFirst(new IWhereFilter<IMapping<ChangeGroup, Tuples._2<Bounds, Bounds>>>() {
        public boolean accept(IMapping<ChangeGroup, Tuples._2<Bounds, Bounds>> g) {
          Bounds left = g.value()._0();
          Bounds right = g.value()._1();
          int v1 = vectorProduct((int) left.start(), (int) right.start(), p.x, p.y);
          int v2 = vectorProduct((int) left.end(), (int) right.end(), p.x, p.y);
          return v1 > 0 && v2 < 0;
        }
      });
      if (group == null) {
        return null;
      } else {
        return MapSequence.fromMap(myChangeGroupDescriptions).get(group.key());
      }
    }
  }
  public void dispose() {
    MPSToolTipManager.getInstance().unregisterComponent(this);
  }
  private int vectorProduct(int left, int right, int x, int y) {
    int x1 = getWidth();
    int y1 = right - left;
    int x2 = x;
    int y2 = y - left;
    int z = x1 * y2 - x2 * y1;
    return z;
  }
}