breakout collision

[lambs4]

I'm writing collision code for my breakout clone. Thanks to the people at allegro.cc I have gotten this far. Now I need more help with collision detection. I can find out if the ball is within the block and have it bounce off the left side, but that's all. anymore help?

   for(x =0; x < MAX_ROW; x++)
   {
      for(y = 0; y < MAX_COL; y++)
     {
        if (ball.x >  blocks[x][y].x && 
            ball.x <= blocks[x][y].width &&
            ball.y >  blocks[x][y].y && 
            ball.y <= blocks[x][y].height) 
       {
            if(blocks[x][y].color > 0)
                {
                    paddle.score += blocks[x][y].color*10;
                    blocks[x][y].color = 0;
                   if(ball.x > blocks[x][y].x)	
                      ball.dx = -BALL_DELTA; // bounce left
                   else if(ball.x <= blocks[x][y].width)
                           ball.dx = BALL_DELTA; // bounce right
                   else if(ball.y > blocks[x][y].y)
                           ball.dy = -BALL_DELTA; // bounce up
                   else if(ball.y <= blocks[x][y].height)
                           ball.dy = BALL_DELTA; // bounce down
                   numOfBlocks--;
                }
			}
		}
	}