package algs55; // section 5.5
import stdlib.*;
/* ***********************************************************************
 *  Compilation:  javac HexDump.java
 *  Execution:    java HexDump < file
 *  Dependencies: BinaryIn.java
 *  Data file:    http://introcs.cs.princeton.edu/stdlib/abra.txt
 *
 *  Reads in a binary file and writes out the bytes in hex, 16 per line.
 *
 *  % more abra.txt
 *  ABRACADABRA!
 *
 *  % java HexDump 16 < abra.txt
 *  41 42 52 41 43 41 44 41 42 52 41 21
 *  96 bits
 *
 *  % hexdump < abra.txt
 *
 *  % od -t x1 < abra.txt
 *  0000000 41 42 52 41 43 41 44 41 42 52 41 21
 *  0000014
 *
 *************************************************************************/

public class HexDump {
  private static BinaryIn binaryIn;

  public static void main(String[] args) {
    //binaryIn = new BinaryIn ("data/abra.txt");
    //binaryIn = new BinaryIn ("abra.bin");
    //binaryIn = new BinaryIn ("genomeTiny.bin");
    binaryIn = new BinaryIn ("4runsOut.bin");
    args = new String[] { "16" };

    int BYTES_PER_LINE = 16;
    if (args.length == 1) {
      BYTES_PER_LINE = Integer.parseInt(args[0]);
    }

    int i;
    for (i = 0; !binaryIn.isEmpty(); i++) {
      if (BYTES_PER_LINE == 0) { binaryIn.readChar(); continue; }
      if (i == 0) StdOut.format("");
      else if (i % BYTES_PER_LINE == 0) StdOut.format("\n", i);
      else StdOut.print(" ");
      char c = binaryIn.readChar();
      StdOut.format("%02x", c & 0xff);
    }
    if (BYTES_PER_LINE != 0) StdOut.println();
    StdOut.println((i*8) + " bits");
  }
}