/* Zplet, a Z-Machine interpreter in Java */
/* Copyright 1996,2001 Matthew T. Russotto */
/* As of 23 February 2001, this code is open source and covered by the */
/* Artistic License, found within this package */

package org.zplet.zmachine.zmachine3;

import org.zplet.zmachine.ZHeader;

class ZHeader3 extends ZHeader {
	final static int FILE_LENGTH_FACTOR = 2;

	ZHeader3(byte[] memory_image) {
		this.memory_image = memory_image;
	}

	public boolean time_game() /* as opposed to score game */
	{
		return ((memory_image[FLAGS1] & 0x02) == 2);
	}

	public void set_status_unavailable(boolean unavail) {
		if (unavail) {
			memory_image[FLAGS1] |= 0x10;
		} else {
			memory_image[FLAGS1] &= 0xEF;
		}
	}

	public void set_splitting_available(boolean avail) {
		if (avail) {
			memory_image[FLAGS1] |= 0x20;
		} else {
			memory_image[FLAGS1] &= 0xDF;
		}
	}

	public void set_variable_default(boolean variable) {
		if (variable) {
			memory_image[FLAGS1] |= 0x40;
		} else {
			memory_image[FLAGS1] &= 0xBF;
		}
	}

	@Override
	public int file_length() {
		int packed_length;

		packed_length = (((memory_image[FILE_LENGTH] & 0xFF) << 8) | (memory_image[FILE_LENGTH + 1] & 0xFF));
		return packed_length * FILE_LENGTH_FACTOR;
	}
}