/*
    * Copyright (c) 2003-2008 by Cosylab d. d.
    *
    * This file is part of CosyBeans-Common.
    *
    * CosyBeans-Common is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
   *
   * CosyBeans-Common is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with CosyBeans-Common.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  package com.cosylab.gui.components.gauger;
  
  import java.awt.Font;
  import java.awt.FontMetrics;
  import java.awt.Graphics2D;
  import java.awt.Rectangle;
  
  import com.cosylab.gui.components.Gauger;
  import com.cosylab.util.PrintfFormat;
  
  
  /**
  /**
   * Value label displays value of gauger in textual form.
   *
   * @author <a href="mailto:ales.pucelj@cosylab.com">Ales Pucelj</a>
   * @version $id$
   */
  public class ValueLabel
  {
  	private boolean unitsVisible = true;
  
  	private Gauger gauger = null;
  
  	//	private Font font = new Font("dialog", Font.PLAIN, 12);
  	private String DEFAULT_FORMAT = "%0.2f";
  	private String DEFAULT_TEXT = "val";
  	private String text = DEFAULT_TEXT;
  //	private String oldText = DEFAULT_TEXT;
  	private String formatString = DEFAULT_FORMAT;
  	private String units = "";
  	private PrintfFormat formatter;
  	private double lastValue = 0.0;
  	private Rectangle bounds;
  	private boolean changeSignificant = true;
  	private int x;
  	private int y;
  
  	/**
  	 * Constructor for ValueLabel.
  	 *
  	 * @param gauger Gauger on which this value will display.
  	 */
  	public ValueLabel(Gauger gauger)
  	{
  		super();
  		this.gauger = gauger;
  		
  		/**
  		 * This is initial height for bounding box, since first time, text has
  		 * not been drawn yet and height is not properly set. It is initialized
  		 * to height of font as later in draw().
  		 */
  		bounds = new Rectangle(0, 0, 1, 16);
  	}
  
  	/**
  	 * Returns bounds of this label.
  	 *
  	 * @return Bounds of text.
  	 */
  	public Rectangle getBounds()
  	{
  		return bounds;
  	}
  
  	/**
  	 * Returns format used by this label.
  	 *
  	 * @return C-Style format.
  	 */
  	public String getFormat()
  	{
  		return formatString;
  	}
  
  	/**
  	 * Returns units symbol to append to text.
  	 *
  	 * @return Units.
 	 */
 	public String getUnits()
 	{
 		return units;
 	}
 
 	private PrintfFormat getFormatter()
 	{
 		if(formatter == null) {
 			formatter = new PrintfFormat(formatString + " " + (unitsVisible ? units : ""));
 		}
 
 		return formatter;
 	}
 
 	/**
 	 * Sets new value to display. Value will be formatted according to the
 	 * format specified and will have units symbol appended to it.
 	 *
 	 * @param value New value to display.
 	 */
 	public void setValue(double value)
 	{
 		String newText;
 		try {
 			newText = getFormatter().sprintf(value);
 		} catch (Exception e) {
 			newText = Double.toString(value);
 		}
 		lastValue = value;
 
 		if(!newText.equals(text)) {
 			text = newText;
 
 			changeSignificant = true;
 		} else {
 			changeSignificant = false;
 		}
 	}
 
 	/**
 	 * Returns whether the change is signifficant.
 	 *
 	 * @return True if text has changed.
 	 */
 	public boolean isChangeSignificant()
 	{
 		return changeSignificant;
 	}
 
 	/**
 	 * Renders this component.
 	 *
 	 * @param g Context to render to.
 	 */
 	public void draw(Graphics2D g)
 	{
 		Font f = gauger.getValueLabelFont();
 		g.setFont(f);
 		
 		
 		FontMetrics metrics = g.getFontMetrics();
 		
 		
 		//		metrics.getStringBounds(outText, g);
 		int width = metrics.stringWidth(text);
 		int height = metrics.getHeight(); //+metrics.getDescent();
 		bounds.setBounds((int)(x - width / 2),
 		    (int)(y - (metrics.getAscent() + metrics.getDescent()) / 2), width,
 		    height);
 		g.drawString(text, x - width/2, y + height/2 );
 	}
 
 	/**
 	 * Sets center position of this component. 
 	 *
 	 * @param x coordinate of label center.
 	 * @param y coordinate of label center.
 	 */
 	public void setPosition(int x, int y)
 	{
 		this.x = x;
 		this.y = y;
 	}
 
 	/**
 	 * Sets format for this label.
 	 *
 	 * @param newFormat C-Style format.
 	 * @see setValue()
 	 */
 	public void setFormat(String newFormat)
 	{
 		if(newFormat != formatString) {
 			formatString = newFormat;
 
 			formatter = null;
 			setValue(lastValue);
 		}
 	}
 
 	/**
 	 * Sets units to append to text.
 	 *
 	 * @param newUnits Units symbol.
 	 * @see setValue()
 	 */
 	public void setUnits(String newUnits)
 	{
 		units = newUnits;
 		formatter = null;
 		setValue(lastValue);
 	}
 
 	/**
 	 * Sets the units visibility.
 	 * 
 	 * @param b
 	 */
 	public void setUnitsVisible(boolean b) {
 		this.unitsVisible = b;
 		formatter = null;
 		setValue(lastValue);
 	}
 
 	/**
 	 * Returns true if units are visible.
 	 * 
 	 * @return
 	 */
 	public boolean isUnitsVisible() {
 		return unitsVisible;
 	}
 }
 
 /* __oOo__ */