/*******************************************************************************
 * Copyright (c) 2013 <Project SWG>
 * 
 * This File is part of NGECore2.
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 * 
 * Using NGEngine to work with NGECore2 is making a combined work based on NGEngine. 
 * Therefore all terms and conditions of the GNU Lesser General Public License cover the combination.
 ******************************************************************************/
package resources.common;

import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import org.apache.mina.core.buffer.IoBuffer;

import engine.resources.common.Utilities;

public class StringUtilities {
	
	final protected static char[] hexArray = {'0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'};
	
	public static String getAsciiString(ByteBuffer buffer) {
		return getString(buffer, "US-ASCII");
	}
	
	public static String getAsciiString(IoBuffer buffer) {
		return getString(buffer, "US-ASCII");
	}
	
	public static String getAsciiString(IoBuffer buffer, boolean integer) {
		return getString(buffer, "US-ASCII", integer);
	}
	
	public static String getUnicodeString(ByteBuffer buffer) {
		return getString(buffer, "UTF-16LE");
	}
	
	public static String getUnicodeString(IoBuffer buffer) {
		return getString(buffer, "UTF-16LE");
	}
	
	public static String getUnicodeString(IoBuffer buffer, boolean integer) {
		return getString(buffer, "UTF-16LE", integer);
	}
	
	public static byte[] getAsciiString(String string) {
		return getString(string, "US-ASCII");
	}
	
	public static byte[] getUnicodeString(String string) {
		return getString(string, "UTF-16LE");
	}
	
	private static String getString(ByteBuffer buffer, String charFormat) {
		String result;
		int length;
		
		if (charFormat == "UTF-16LE") {
			length = buffer.order(ByteOrder.LITTLE_ENDIAN).getInt();
		} else {
			length = buffer.order(ByteOrder.LITTLE_ENDIAN).getShort();
		}
		
		int bufferPosition = buffer.position();
		
		try {
			result = new String(buffer.array(), bufferPosition, length, charFormat);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
			return "";
		}
		
		buffer.position(bufferPosition + length);
		
		return result;
	}
	
	private static String getString(IoBuffer buffer, String charFormat) {
		String result;
		int length;
		
		if (charFormat == "UTF-16LE") {
			length = buffer.order(ByteOrder.LITTLE_ENDIAN).getInt();
		} else {
			length = buffer.order(ByteOrder.LITTLE_ENDIAN).getShort();
		}
		
		int bufferPosition = buffer.position();
		
		try {
			result = new String(buffer.array(), bufferPosition, length, charFormat);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
			return "";
		}
		
		buffer.position(bufferPosition + length);
		
		return result;
	}
	
	private static String getString(IoBuffer buffer, String charFormat, boolean integer) {
		String result;
		int length;
		
		if (charFormat == "UTF-16LE") {
			if (integer) {
				length = buffer.order(ByteOrder.LITTLE_ENDIAN).getInt() * 2;
			} else {
				length = buffer.order(ByteOrder.LITTLE_ENDIAN).getInt();
			}
		} else {
			if (integer) {
				length = buffer.order(ByteOrder.LITTLE_ENDIAN).getInt();
			} else {
				length = buffer.order(ByteOrder.LITTLE_ENDIAN).getShort();
			}
		}
		
		int bufferPosition = buffer.position();
		
		try {
			result = new String(buffer.array(), bufferPosition, length, charFormat);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
			return "";
		}
		
		buffer.position(bufferPosition + length);
		
		return result;
	}
	
	private static byte[] getString(String string, String charFormat) {
		ByteBuffer result;
		int length = 2 + string.length();
		
		if (charFormat == "UTF-16LE") {
			result = ByteBuffer.allocate(length * 2).order(ByteOrder.LITTLE_ENDIAN);
			result.putInt(string.length());
		} else {
			result = ByteBuffer.allocate(length).order(ByteOrder.LITTLE_ENDIAN);
			result.putShort((short)string.length());
		}
		
		try {
			result.put(string.getBytes(charFormat));
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
			return new byte[] { };
		}
		
		return result.array();		
	}
	
	public static String bytesToHex(byte[] bytes) {
		char[] hexChars = new char[bytes.length * 2];
		int v;
		
		for ( int j = 0; j < bytes.length; j++ ) {
			v = bytes[j] & 0xFF;
			hexChars[j * 2] = hexArray[v >>> 4];
			hexChars[j * 2 + 1] = hexArray[v & 0x0F];
		}
		
		return new String(hexChars);
	}
	
	public static void printBytes(byte[] bytes) {
		System.out.println(Utilities.getHexString(bytes));
	}
	
}