package lab06_test;

import java.util.*;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.text.*;

public class DisplayTree {
	
	int data;                        // Node data stored as an int value. 
	
	DisplayTree[] children = null;   // Children stored in an array.
	
	void preorderDisplayText( int cur_offset, boolean same_line )
	{
		/* Performs a preorder traversal to display the tree via text. 
		 * Inputs:
				cur_offset: gives the amount of space offset for the current node.
				same_line:  if true, the current node is on the same line as previous
				 			node, print ' - ' and then display the node value.
				            if false, the current node is on a separate line, 
				            print adequate space using print_space()
				            then print ' \\ ' and the node value. 
				            
		   Comments:
		        Use System.out.printf("%2d", data); to allocate two characters for 
		        each node value.
		*/
		
		if( same_line )
		{
			System.out.print(" - ");
			System.out.printf("%2d", data);
		}
		else
		{
			System.out.println();
			printSpace(cur_offset);
			System.out.print(" \\ ");
			System.out.printf("%2d", data);
		}
		cur_offset = cur_offset + 5;
		if( children.length > 0 )
		{
			children[0].preorderDisplayText( cur_offset, true );
			for(int i = 1; i < children.length; i++ )
			{
				children[i].preorderDisplayText( cur_offset, false );
			}
		}
	}
	
	void printSpace(int length)
	{
		for( int i = 0; i < length; i++ )
			System.out.print(" ");
	}
	
	int preorderDisplayGraphics(Graphics g, int x_offset, int y_offset )
	{
		int dia = 40, x_jump = 70, y_jump = 50;
		
		drawNumberCircle( g, x_offset, y_offset, dia );
		
		int new_x = x_offset + x_jump;
		int new_y = y_offset;
		
		if( children.length > 0 )
		{
			for(int i = 0; i < children.length; i++ )
			{
				drawLine(g, x_offset, y_offset, new_x, new_y, dia/2 );
				new_y = y_jump + children[i].preorderDisplayGraphics(g, new_x, new_y);
			}
			new_y -= y_jump;
		}
		return new_y;
	}
	
	void drawNumberCircle(Graphics g, int x, int y, int dia)
	{
		g.setColor(Color.ORANGE);
		g.fillOval( x, y, dia, dia );

		g.setColor(Color.RED);
		g.setFont(new Font("Verdana",Font.BOLD,15));
		g.drawString( ""+data, x + dia/2 - 12, y + dia/2 +5 );
	}
	
	void drawLine( Graphics g, int x1, int y1, int x2, int y2, int radius )
	{
		x1 = x1 + radius;
		y1 = y1 + radius;
		x2 = x2 + radius;
		y2 = y2 + radius;
		double dist = Math.sqrt(Math.pow((x1 - x2), 2)+Math.pow((y1 - y2), 2));
		double alpha1 = radius / dist;
		double alpha2 = (dist - radius) / dist;
		int xn1 = (int)(alpha1 * x1 + (1 - alpha1) * x2);
		int yn1 = (int)(alpha1 * y1 + (1 - alpha1) * y2);
		int xn2 = (int)(alpha2 * x1 + (1 - alpha2) * x2);
		int yn2 = (int)(alpha2 * y1 + (1 - alpha2) * y2);
		
		g.drawLine(xn1, yn1, xn2, yn2);
	}
	
	static Random rand = new Random(12345);

	DisplayTree( int height )
	{
		data = rand.nextInt(99);
		int numChildren = rand.nextInt(4);
		if( height > 0 && numChildren > 0 )
		{
			children = new DisplayTree[numChildren];
			for(int i = 0; i < numChildren; i++ )
				children[i] = new DisplayTree(height - 1);
		}
		else
			children = new DisplayTree[0];
	}
}