// CS1501 -- Summer 2006
// Intro to using binary files in Java for input and output.  This program will
// simply copy any file, whether it is text, executable or anything else.
// It will then output the 8 leftmost bits and the 8 rightmost bits of an
// integer to demonstrate some binary operations.  Finally, it will write
// some odd-length values to the file and read them back using buffers.

import java.io.*;
import javax.swing.*;

public class binaryio
{
	public static void main(String [] args)
	{
		FileInputStream infile = null;
		FileOutputStream outfile = null;

		String ifname = null;   // string for name of input file
		String ofname = null;   // string for name of output file

		int ch;

		while (true)
		{
			try
			{
				ifname = JOptionPane.showInputDialog(null, "File name?");
				infile = new FileInputStream(ifname);
				break;
			}
			catch (IOException e)
			{
				System.out.println("File " + ifname + " could not be opened");
			}
		}

		ofname = ifname + ".cop";
		try
		{
			outfile = new FileOutputStream(ofname);

			ch = infile.read();       // Read ahead because we must test for end of file
			while (ch != -1)
			{
				outfile.write(ch);
				ch = infile.read();  // get the next byte
			}
			infile.close();
			outfile.close();

		}
		catch (IOException e1)
		{
			System.out.println("Some bogusness with the file");
			System.exit(0);
		}

		FileOutputStream newFile = null;
		try
		{
			newFile = new FileOutputStream("wacky.out");
			int val = 1090519178;
			// 2^30 + 2^24 + 2^7 + 2^3 + 2^1
			int bits = 8;
			int leftout = 0;
			int rightout = 0;
			leftout = val >> (32-bits); // should be 01000001 = 65
			rightout = (val << (32 - bits)) >> (32 - bits);
			// should be 10001010 = 138
			newFile.write(leftout);	// write a byte
			newFile.write(rightout);	// write a byte
		  
			long buffer = 0L;
			long ander = (1L << 32) - 1;	// leftmost 32 bits are 0
											// rightmost 32 bits are 1
			int bitsUsed = 0;
			// The codes below require the number of bits shown afterward
			int [] codes = {8, 17, 3, 65, 63, 128};
			int [] numb = {4, 5, 2, 7, 6, 8};
			
			for (int i = 0; i < codes.length; i++)
			{
				// Trace this on paper to see what it does
				buffer = buffer | (codes[i] << (32 - bitsUsed - numb[i]));
				buffer = buffer & ander; // Zeroify left 32 bits -- this is
						// done because Java does not have the unsigned int
						// type
				bitsUsed += numb[i];
			}
			while (bitsUsed > 0)
			{
				newFile.write((int) (buffer >> 24));  // write bits 33-40
				// (leftmost bits of 32 bit int)
				buffer = buffer << 8;    // shift 8 bits left
				buffer = buffer & ander; // zeroify left 32 bits
				bitsUsed -= 8;
			}
		  
			newFile.close();

			FileInputStream reFile = new FileInputStream("wacky.out");
			int lval = reFile.read();
			int rval = reFile.read();
		 
			System.out.println("leftmost " + bits + " bits = " + lval);
			System.out.println("rightmost " + bits + " bits = " + rval);
			buffer = 0L;
			bitsUsed = 0;
			for (int i = 0; i < 4; i++)	// read next 4 bytes
			{
				rval = reFile.read();	// read a byte
				// Trace to see what code below does
				buffer = buffer | (rval << (32 - bitsUsed - 8));
				buffer = buffer & ander; // zeroify left 32 bits
				bitsUsed += 8;
			}
			for (int i = 0; i < numb.length; i++)
			{
				lval = (int) (buffer >> (32 - numb[i]));
				buffer = buffer << numb[i];
				buffer = buffer & ander;  // zeroify left 32 bits
				System.out.println("Next value is " + lval);
			}
			reFile.close();
		}
		catch (Exception e)
		{   System.out.println("Some exception " + e + " has occurred"); }

	}
}