/**
*		@author Kaushik Raj
*		@see	http://www.cis.syr.edu/~kraj/java/
*		@email	kraj@syr.edu
*	
*		(c) copyright-98 Kaushik Raj
*		All Rights Reserved.
*
*       This source code is free for all non-commercial purposes, as long as the name
*       and the url address given above is written with the modified program. The author does not gives
*       the permission to publish the source code in any book or any other publishing media.
*
*
*       The author doesnot takes any responsibility for the software/hardware damages
*       that may occur due to this program.
*/


/**
*	Part of this program has been taken from MazeGen.java
*
*	@see http://www.mazeworks.com/mazegen/mazegen.htm
*/

/**
*	File : MazeCanvas.java
*	Last update : 10 July,1998
*/
import java.awt.*;
import java.applet.*;
import java.util.*;

/**
*	draws the maze canvas using image buffering
*/   
 public class MazeCanvas extends Canvas {
   static final int BORDER=10, MAX_CELL_SIZE=20 ;
   private int width, height, mzWidth, mzHeight, cellSize,
               wOffset, hOffset, rows, cols, pathSize,
			   nwPathOffset, sePathOffset ;

   /** for double buffering */
   Image bufferImage ;
   Graphics buffer ;

   /** handle */
   MazeGame mg ;

   private Font font;

   /** intialisationm with height and lenght of the canvas */
   MazeCanvas(int mcw,int mch) { 
      width = mcw ; height = mch ;
   }

   /** initialises the maze and the canvas */
   private void drawInit(Maze mz) {
      cols = mz.getCols() ; rows = mz.getRows() ;
      cellSize = (int)Math.min(MAX_CELL_SIZE,
                  Math.min((width-BORDER)/cols,(height-BORDER)/rows)) ;
      mzWidth = cellSize * cols ;
      mzHeight = cellSize * rows ;
      wOffset = (int)((width-mzWidth)/2) ;
      hOffset = (int)((height-mzHeight)/2) ;
      pathSize = (int)(cellSize/2)-1 ;
      nwPathOffset = (int)((cellSize-pathSize)/2) ;
      sePathOffset = cellSize - pathSize - nwPathOffset ;

      if (buffer==null) {
         bufferImage = createImage(width,height) ;
         buffer = bufferImage.getGraphics() ;
      }
      // draw background
      buffer.setColor(mg.appletColor);
      buffer.fillRect(0,0,width,height) ;
      buffer.setColor(mg.bkgrndColor);
      buffer.fillRect(wOffset,hOffset,mzWidth,mzHeight) ;
      // draw outer maze frame
      buffer.setColor(mg.frameColor);
      buffer.draw3DRect(wOffset-2, hOffset-2, mzWidth+4, mzHeight+4, true) ;
      buffer.drawRect(wOffset-1, hOffset-1, mzWidth+2, mzHeight+2) ;
   }

   /** initialisation */
   public void init(){
      if (buffer==null) {
         bufferImage = createImage(width,height) ;
         buffer = bufferImage.getGraphics() ;
      }
   }

   // draw full generated maze with start and end points
   // called if Show Gen off
   public void drawMaze(Maze mz) {
      drawInit(mz) ;
      buffer.setColor(mg.wallColor);
      for (int i=0; i<cols; i++) {
         for (int j=0; j<rows; j++) {
            // only drawing North and West walls
            if ( (j!=0)&&((mz.getCell(i,j)&0x01)!=0) ) {
               buffer.drawLine((wOffset+(i*cellSize)), 
                               (hOffset+(j*cellSize)),
                               (wOffset+((i+1)*cellSize)),
                               (hOffset+(j*cellSize))) ;
            }
            if ( (i!=0)&&((mz.getCell(i,j)&0x08)!=0) ) {
               buffer.drawLine((wOffset+(i*cellSize)), 
                               (hOffset+(j*cellSize)),
                               (wOffset+(i*cellSize)),
                               (hOffset+((j+1)*cellSize))) ;
            }
         }
      }
      // draw inner frame
	  
      buffer.setColor(mg.frameColor);
      buffer.draw3DRect(wOffset, hOffset, mzWidth, mzHeight, false) ;
	  
   }

 
   // draw the colorful start and end squares
   void drawhome(Point endPt,Image endImage) {
	  
	   if (buffer==null) System.out.println("Buffer Null");
	   int x,y;
	   x=endPt.x*cellSize+wOffset+20;
	   y=endPt.y*cellSize+hOffset-10;
		buffer.drawImage(endImage,x,y,this);
   }

   public void paint(Graphics g) { update(g) ; }

   public void update(Graphics g) { 
      if (bufferImage!=null) g.drawImage(bufferImage,0,0,this) ;
   }

   /** returns the blocked clicked for food */
   public Dimension blockClicked(int x,int y){
	   int xbl=(int)((x-wOffset)/cellSize);
	   int ybl=(int)((y-hOffset)/cellSize);

	   return (new Dimension(xbl,ybl));
   }

   /** draws the stuff erasing earlier stuff */
   public void drawFresh(Maze mz,Image homeimage){
	   drawMaze(mz);
	   drawhome(mz.getEnd(),homeimage);
	   //repaint();
   }

   /** drwas all the stuff */
   synchronized public void drawAllRatAndFood(Maze mz,Image homeimage,Point ratPos,Image ratImage,int foodPos[][],Image foodImage){
	   int ratx=ratPos.x*cellSize+wOffset+(int)((cellSize-ratImage.getWidth(null))/2);
	   int raty=ratPos.y*cellSize+hOffset+(int)((cellSize-ratImage.getHeight(null))/2);

	   int foodx,foody;
	   boolean ratAndFood=false;

	   drawFresh(mz,homeimage);

	   for (int i=0;i<mz.getCols();i++){
		   for (int j=0;j<mz.getRows();j++){
				if (foodPos[i][j]==1){
					if ((i==ratPos.x)&&(j==ratPos.y)) ratAndFood=true;

					foodx=i*cellSize+wOffset+(int)((cellSize-foodImage.getWidth(null))/2);
					foody=j*cellSize+hOffset+(int)((cellSize-foodImage.getHeight(null))/2);
					// draw the food Image at that point
					//System.out.println("drawing food");
					buffer.drawImage(foodImage,foodx,foody,this);
				}
		   }
	   }//drawing of the food is over now

	   if (ratAndFood) {//clear the buffer of food
			buffer.setColor(mg.bkgrndColor);
			buffer.fillRect((wOffset+(ratPos.x*cellSize)+1),
				          (hOffset+(ratPos.y*cellSize)+1),
					      (cellSize-2),(cellSize-2));
	   }

	   buffer.drawImage(ratImage,ratx,raty,this);
	   repaint();
   }//drawAllRatAndFood()

   /** to display game has been won */
   public void gameWon(){
	  buffer.setColor(mg.appletColor);
      buffer.fillRect(0,0,width,height) ;
	  setFontData();
	  buffer.setColor(Color.red);
	  buffer.drawString("Game Won",135,50);
	  gameCopyRight();
	  repaint();
   }

   /** to display game has been lost */
   public void gameLost(){
      buffer.setColor(mg.appletColor);
      buffer.fillRect(0,0,width,height) ;
	  setFontData();
	  buffer.setColor(Color.red);
	  buffer.drawString("Game Lost",135,50);
      gameCopyRight();
	  repaint();

   }

   /** copy right stuff */
   private void gameCopyRight(){
	  buffer.setColor(Color.white);
	  buffer.drawString("(c) Copyright -98",110,140);
	  buffer.drawString("Kaushik Raj <kraj@syr.edu>",60,170);
	  buffer.setColor(Color.yellow);
	  buffer.drawString("http://web.syr.edu/~kraj/",70,250);
	  repaint();
   }

   private void setFontData(){
	   font=new Font("Times",Font.PLAIN,20);
	   buffer.setFont(font);
   }

   /** when the images are being downloaded */
   public void loadingImages(){
	  buffer.setColor(mg.appletColor);
      buffer.fillRect(0,0,width,height) ;
	  setFontData();
	  buffer.setColor(Color.red);
	  buffer.drawString("Loading Images",135,50);
	  gameCopyRight();
	  repaint();
   }
}