// Class to define a tetris piece and its various movements.

import java.awt.*;

public class TetrisPiece
{
	private TetrisBlock[] blocks;
	private int[] initial_position;
	
	// Which rotation position the piece is in.
	private int rotation_sequence;
	
	// Changes in position for right rotations.
	private int[] rot3to0;
	private int[] rot0to1;
	private int[] rot1to2;
	private int[] rot2to3;
	
	// Changes in position for left rotations.
	private int[] rot0to3;
	private int[] rot1to0;
	private int[] rot2to1;
	private int[] rot3to2;
	
	public TetrisPiece (int tetroid_code, int[] initial_position, int[] rot3to0, int[] rot0to1, int[] rot1to2, int[] rot2to3, int[] rot0to3, int[] rot1to0, int[] rot2to1, int[] rot3to2)
	{
		this.initial_position = initial_position;
		this.rot3to0 = rot3to0;
		this.rot0to1 = rot0to1;
		this.rot1to2 = rot1to2;
		this.rot2to3 = rot2to3;
		this.rot0to3 = rot0to3;
		this.rot1to0 = rot1to0;
		this.rot2to1 = rot2to1;
		this.rot3to2 = rot3to2;
		
		blocks = new TetrisBlock[4];
		
		rotation_sequence = 0;
		
		blocks[0] = new TetrisBlock(tetroid_code, initial_position[0], initial_position[1]);
		blocks[1] = new TetrisBlock(tetroid_code, initial_position[2], initial_position[3]);
		blocks[2] = new TetrisBlock(tetroid_code, initial_position[4], initial_position[5]);
		blocks[3] = new TetrisBlock(tetroid_code, initial_position[6], initial_position[7]);
	}
	
	// Shift the tetris piece down.
	public void moveDown()
	{
		for (int i = 0; i < 4; i++)
			blocks[i].moveDown();
	}
	
	// Check to see if the current position of the tetris piece is a valid one in the array.
	public boolean checkPosition(TetrisMatrix tm)
	{
		for (int i = 0; i < 4; i++)
			if (blocks[i].checkPosition(tm) == false)
				return false;
		
		return true;
	}
	
	// Move the tetris piece left.
	public void moveLeft(TetrisMatrix tm)
	{
		if (checkLeft(tm))
			for (int i = 0; i < 4; i++)
				blocks[i].moveLeft();
	}
	
	// Check to see if the tetris piece can move left.
	public boolean checkLeft(TetrisMatrix tm)
	{
		for (int i = 0; i < 4; i++)
			if (blocks[i].checkLeft(tm) == false)
				return false;
		
		return true;
	}
	
	// Move the tetris piece to an arbitrary location.
	public void move(int x, int y)
	{
		for (int i = 0; i < 4; i++)
			blocks[i].modifyPosition(x, y);
	}	
	
	// Check to see if the tetris piece can move right.
	public boolean checkRight(TetrisMatrix tm)
	{
		for (int i = 0; i < 4; i++)
			if (blocks[i].checkRight(tm) == false)
				return false;
		
		return true;
	}
	
	// Move the tetris piece to the right.
	public void moveRight(TetrisMatrix tm)
	{
		if (checkRight(tm))
			for (int i = 0; i < 4; i++)
				blocks[i].moveRight();
	}
	
	// Check to see if the tetris piece can move down.
	public boolean checkDown(TetrisMatrix tm)
	{
		for (int i = 0; i < 4; i++)
			if (blocks[i].checkDown(tm) == false)
				return false;
		
		return true;
	}
	
	// Rotate the tetris piece left.
	public void rotateLeft(TetrisMatrix tm)
	{
		int[] p = new int[8];
		
		switch (rotation_sequence)
		{
			case 0:
				p = rot0to3;
				break;
			case 1:
				p = rot1to0;
				break;
			case 2:
				p = rot2to1;
				break;
			case 3:
				p = rot3to2;
				break;
		}
		
		blocks[0].modifyPosition(p[0], p[1]);
		blocks[1].modifyPosition(p[2], p[3]);
		blocks[2].modifyPosition(p[4], p[5]);
		blocks[3].modifyPosition(p[6], p[7]);
		
		if (rotation_sequence == 0)
			rotation_sequence = 3;
		else
			rotation_sequence--;
		
		// Check to see if valid rotation and try to correct
		for (int i = 0; i < 4; i++)
			if (blocks[i].checkRotatePosition(tm) == false)
				rotateRight(tm);
	}
	
	// Rotate the tetris piece right.
	public void rotateRight(TetrisMatrix tm)
	{
		int[] p = new int[8];
		
		switch (rotation_sequence)
		{
			case 0:
				p = rot0to1;
				break;
			case 1:
				p = rot1to2;
				break;
			case 2:
				p = rot2to3;
				break;
			case 3:
				p = rot3to0;
				break;
		}
		
		blocks[0].modifyPosition(p[0], p[1]);
		blocks[1].modifyPosition(p[2], p[3]);
		blocks[2].modifyPosition(p[4], p[5]);
		blocks[3].modifyPosition(p[6], p[7]);
		
		if (rotation_sequence == 3)
			rotation_sequence = 0;
		else
			rotation_sequence++;
		
		// Check to see if valid rotation and try to correct
		for (int i = 0; i < 4; i++)
			if (blocks[i].checkRotatePosition(tm) == false)
				rotateLeft(tm);
		
	}
	
	// Get the current x position of the tetris piece.
	public int getX()
	{
		return blocks[1].getX();
	}
	
	// Get the current y position of the tetris piece.
	public int getY()
	{
		return blocks[1].getY();
	}
	
	// Return the array of tetris blocks making up this piece.
	public TetrisBlock[] getBlocks ()
	{
		return blocks;
	}
	
	// Draw the tetris piece one block at a time.
	public void draw(Graphics g)
	{
		for (int i = 0; i < 4; i++)
			blocks[i].draw(g);
	}
}