platform/platform-impl/src/com/intellij/openapi/diff/ex/DiffStatusBar.java

/*
 * Copyright 2000-2012 JetBrains s.r.o.
 *
 * 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.intellij.openapi.diff.ex;

import com.intellij.openapi.editor.colors.EditorColorsManager;
import com.intellij.openapi.editor.colors.EditorColorsScheme;
import com.intellij.util.ui.GraphicsUtil;
import com.intellij.util.ui.UIUtil;
import org.jetbrains.annotations.Nullable;

import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

/**
 * @author Yura Cangea
 */
public class DiffStatusBar extends JPanel {
  private final Collection<JComponent> myLabels = new ArrayList<JComponent>();

  private final JLabel myTextLabel = new JLabel("");
  private static final int COMP_HEIGHT = 30;
  private EditorColorsScheme myColorScheme = null;

  public <T extends LegendTypeDescriptor> DiffStatusBar(List<T> types) {
    for (T differenceType : types) {
      addDiffType(differenceType);
    }
    initGui();
  }

  private void addDiffType(final LegendTypeDescriptor diffType){
    addComponent(diffType);
  }

  private void addComponent(final LegendTypeDescriptor diffType) {
    JComponent component = new SingleDiffLegendComponent(diffType);
    myLabels.add(component);
  }

  public Dimension getMinimumSize() {
    Dimension p = super.getPreferredSize();
    Dimension m = super.getMinimumSize();
    return new Dimension(m.width, p.height);
  }

  public Dimension getMaximumSize() {
    Dimension p = super.getPreferredSize();
    Dimension m = super.getMaximumSize();
    return new Dimension(m.width, p.height);
  }

  public void setText(String text) {
    myTextLabel.setText(text);
  }

  private void initGui() {
    JComponent filler = new JComponent() {
      @Override
      public Dimension getPreferredSize() {
        return myTextLabel.getPreferredSize();
      }
    };
    setLayout(new BorderLayout());
    setBorder(BorderFactory.createEmptyBorder(3, 20, 3, 20));

    add(myTextLabel, BorderLayout.WEST);
    Box box = Box.createHorizontalBox();
    box.add(Box.createHorizontalGlue());
    JPanel panel = new JPanel(new GridLayout(1, myLabels.size(), 0, 0));
    for (final JComponent myLabel : myLabels) {
      panel.add(myLabel);
    }
    panel.setMaximumSize(panel.getPreferredSize());
    box.add(panel);
    box.add(Box.createHorizontalGlue());
    add(box, BorderLayout.CENTER);

    add(filler, BorderLayout.EAST);
  }

  public void setColorScheme(EditorColorsScheme colorScheme) {
    EditorColorsScheme oldScheme = myColorScheme;
    myColorScheme = colorScheme;
    if (oldScheme != colorScheme) repaint();
  }

  public interface LegendTypeDescriptor {
    String getDisplayName();
    @Nullable
    Color getLegendColor(EditorColorsScheme colorScheme);
  }

  private class SingleDiffLegendComponent extends JPanel {
    private static final int HORIZONTAL_PADDING = 70;
    private final LegendTypeDescriptor myDiffType;

    public SingleDiffLegendComponent(LegendTypeDescriptor diffType) {
      myDiffType = diffType;
    }

    public void paint(Graphics g) {
      setBackground(UIUtil.getPanelBackground());
      super.paint(g);
      GraphicsUtil.setupAntialiasing(g);
      FontMetrics metrics = getFontMetrics(getFont());

      EditorColorsScheme colorScheme = myColorScheme != null
                                       ? myColorScheme
                                       : EditorColorsManager.getInstance().getGlobalScheme();
      g.setColor(myDiffType.getLegendColor(colorScheme));
      final int RECT_WIDTH = 35;
      g.fill3DRect(0, (getHeight() - 10) / 2, RECT_WIDTH, 10, true);

      Font font = g.getFont();
      if (font.getStyle() != Font.PLAIN) {
        font = font.deriveFont(Font.PLAIN);
      }
      g.setFont(font);
      g.setColor(UIUtil.getLabelForeground());
      int textBaseline = (getHeight() - metrics.getHeight()) / 2 + metrics.getAscent();
      g.drawString(myDiffType.getDisplayName(), RECT_WIDTH + UIUtil.DEFAULT_HGAP, textBaseline);
    }

    @Override
    public Dimension getPreferredSize() {
      FontMetrics metrics = getFontMetrics(getFont());
      int stringWidth = (int)metrics.getStringBounds(myDiffType.getDisplayName(), getGraphics()).getWidth();
      return new Dimension(HORIZONTAL_PADDING + stringWidth, COMP_HEIGHT);
    }

    @Override
    public Dimension getMinimumSize() {
      return getPreferredSize();
    }
  }
}