package pad.prac1;

import java.util.Observable;
import java.util.Observer;
import java.util.Scanner;
import java.util.regex.Pattern;

public class Console implements Observer 
{
	private Coordinate currentXY;
	//private int numRows;
	private int numCols;
	
	public Console()
	{
		currentXY = new Coordinate(0,0);
	}
	
	public void moveCursorTo(int pos, int currentPos, int length)
	{
		updateTermSize();
		updateCurrentPos();
		if(pos > currentPos)
		{
			while((pos-currentPos) >= numCols)
			{
				currentPos += numCols - currentXY.x()+1;
				System.out.print((char)EditableBufferedReader.ESC);
				System.out.print((char)EditableBufferedReader.ESC_SEQ);
				System.out.print((char)EditableBufferedReader.DOWN);
				currentXY.setY(currentXY.y()+1);
				System.out.print((char)EditableBufferedReader.ESC);
				System.out.print((char)EditableBufferedReader.ESC_SEQ);
				System.out.print(numCols-1);
				System.out.print((char)EditableBufferedReader.BACKWARD);
				currentXY.setX(1);
			}
			if(pos > currentPos)
			{
				System.out.print((char)EditableBufferedReader.ESC);
				System.out.print((char)EditableBufferedReader.ESC_SEQ);
				System.out.print(pos - currentPos);
				System.out.print((char)EditableBufferedReader.FORWARD);
			}
		}
		else if(pos < currentPos)
		{
			System.err.println(currentPos);
			System.err.println(pos);
			System.err.println(currentXY);
			while((currentPos-pos) >= currentXY.x())
			{
				currentPos -= currentXY.x();
				System.out.print((char)EditableBufferedReader.ESC);
				System.out.print((char)EditableBufferedReader.ESC_SEQ);
				System.out.print((char)EditableBufferedReader.UP);
				currentXY.setY(currentXY.y()-1);
				System.out.print((char)EditableBufferedReader.ESC);
				System.out.print((char)EditableBufferedReader.ESC_SEQ);
				System.out.print(numCols);
				System.out.print((char)EditableBufferedReader.FORWARD);
				currentXY.setX(numCols);
			}
			if(pos < currentPos)
			{
				System.out.print((char)EditableBufferedReader.ESC);
				System.out.print((char)EditableBufferedReader.ESC_SEQ);
				System.out.print(currentPos-pos);
				System.out.print((char)EditableBufferedReader.BACKWARD);
			}
		}
	}
	
	public void updateCurrentPos()
    {
        Coordinate pos = getCurrentPos();
        currentXY.setY(pos.y());
        currentXY.setX(pos.x());
	}
	
	public void updateTermSize()
	{
        System.out.print((char)EditableBufferedReader.ESC);
        System.out.print((char)EditableBufferedReader.ESC_SEQ);
        System.out.print("18t");
        Pattern pattern = Pattern.compile("8;(\\d+);(\\d+)");
        Scanner scanner = new Scanner(System.in);
		scanner.findWithinHorizon(pattern,0);
		numCols = Integer.parseInt(scanner.match().group(2));
		//numRows = Integer.parseInt(scanner.match().group(1));
	}
	
	public Coordinate getCurrentPos()
	{
        System.out.print((char)EditableBufferedReader.ESC);
        System.out.print((char)EditableBufferedReader.ESC_SEQ);
        System.out.print("6n");
        Pattern pattern = Pattern.compile("(\\d+);(\\d+)");
        Scanner scanner = new Scanner(System.in);
		scanner.findWithinHorizon(pattern,0);
		int x = Integer.parseInt(scanner.match().group(2));
		int y = Integer.parseInt(scanner.match().group(1));
        return new Coordinate(x,y);
	}

	
	
	
	private void insertSpace()
	{
		System.out.print((char)EditableBufferedReader.ESC);
		System.out.print((char)EditableBufferedReader.ESC_SEQ);
		System.out.print((char)EditableBufferedReader.INS_SPACE);
	}
	
	private void delChar()
	{
		System.out.print((char)EditableBufferedReader.ESC);
		System.out.print((char)EditableBufferedReader.ESC_SEQ);
		System.out.print((char)EditableBufferedReader.DEL_CHAR);
	}
	
	public void addChar(char c, Line line)
	{
		if(line.getCursorPosition() != line.length()+1)
		{
			insertSpace();
		}
		System.out.print(c);
	}
	
	public void update(Observable obs, Object arg)
	{
		Line line = (Line)obs;
		Command cmd = (Command)arg;		
		switch(cmd.getType())
		{
			case Command.INSERT_CHAR:
				addChar((char)cmd.getValue(),line);
			break;
			
			case Command.DELETE_CHAR:
				delChar();
			break;
			
			case Command.MOVE_CURSOR:
				moveCursorTo(cmd.getValue(),line.getCursorPosition(),line.length());
			break;
		}
	}
}