/*
    * The baseCode project
    * 
    * Copyright (c) 2011 University of British Columbia
    * 
    * 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 ubic.basecode.graphics;
  
  import java.awt.Color;
  import java.awt.Dimension;
  import java.awt.Graphics;
  import java.awt.Graphics2D;
  
  import javax.swing.JLabel;
  
  /**
   * Color gradient without any text
   * 
   * @author wbraynen
   * 
   */
  class JGradientLabel extends JLabel {
  
      private static final int MINHEIGHT = 10;
      private static final int MINWIDTH = 100;
      private static final long serialVersionUID = 348823467068723730L;
      private Color[] m_colorMap;
  
      /**
       * Creates a new instance of JGradientLabel
       * 
       * @param colorMap Color[]
       */
      public JGradientLabel( Color[] colorMap ) {
  
          if ( 0 == colorMap.length ) {
              // if there are no colors, default to grey for both colors
              colorMap = new Color[2];
              colorMap[0] = colorMap[1] = Color.LIGHT_GRAY;
          } else if ( 1 == colorMap.length ) {
              // if there is only one color, make the second color the same
              Color color = colorMap[0];
              colorMap = new Color[2];
              colorMap[0] = colorMap[1] = color;
          }
  
          m_colorMap = colorMap;
  
          Dimension d = new Dimension( MINWIDTH, MINHEIGHT );
          setSize( d );
          this.setText( "Scale bar should be here" ); // forces repaint.
          setMinimumSize( d );
      }
  
      /**
       * @param g
       * @param x
       * @param y
       * @return actual width
       */
      public int drawAtLocation( Graphics g, int x, int y ) {
          Graphics2D g2 = ( Graphics2D ) g;
          Color oldColor = g2.getColor();
          final int width = getWidth();
          final int height = getHeight();
  
          assert width > 0;
          assert height > 0;
  
          int numColors = m_colorMap.length;
  
          int intervalWidth = ( int ) Math.ceil( width / ( double ) numColors );
  
          int currentX = x;
          for ( int i = 0; i < numColors; i++ ) {
  
              Color color1 = m_colorMap[i];
  
              g2.setPaint( color1 );
              g2.fillRect( currentX, y, intervalWidth, height );
  
              currentX += ( double ) width / numColors;
          }
          g2.setColor( oldColor );
          return currentX - x;
      }
  
      public Color[] getColorMap() {
          return m_colorMap;
      }
  
     public void setColorMap( Color[] mColorMap ) {
         m_colorMap = mColorMap;
         this.repaint();
     }
 
     /*
      * (non-Javadoc)
      * 
      * @see javax.swing.JComponent#paintComponent(java.awt.Graphics)
      */
     @Override
     protected void paintComponent( Graphics g ) {
         super.paintComponent( g );
         drawAtLocation( g, 0, 0 );
     }
 }