/*
 * COPYRIGHT NOTICE 
 * Copyright (C) 2015, Jhuster, All Rights Reserved
 * Author: Jhuster(lujun.hust@gmail.com)
 * 
 * https://github.com/Jhuster/TLV
 * 
 * This library 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 2.1 of the License, 
 * or (at your option) any later version.
 */
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.HashMap;
import java.util.Set;

public class TlvBox {

 private static final ByteOrder DEFAULT_BYTE_ORDER = ByteOrder.LITTLE_ENDIAN;
 
 private HashMap<Integer, byte[]> mObjects;
 private int mTotalBytes = 0;

 public TlvBox() {
 mObjects = new HashMap<Integer, byte[]>();
 }
 
 public static TlvBox parse(byte[] buffer, int offset, int length) {
 
 TlvBox box = new TlvBox();
 
 int parsed = 0;
 while (parsed < length) {
 int type = ByteBuffer.wrap(buffer,offset + parsed, 4).order(DEFAULT_BYTE_ORDER).getInt();
 parsed += 4;
 int size = ByteBuffer.wrap(buffer,offset + parsed, 4).order(DEFAULT_BYTE_ORDER).getInt();
 parsed += 4;
 byte[] value = new byte[size];
 System.arraycopy(buffer, offset+parsed, value, 0, size);
 box.putBytesValue(type, value);
 parsed += size;
 } 
 return box;
 }
 
 public byte[] serialize() {
 int offset = 0;
 byte[] result = new byte[mTotalBytes]; 
 Set<Integer> keys = mObjects.keySet(); 
 for (Integer key : keys) {
 byte[] bytes = mObjects.get(key);
 byte[] type = ByteBuffer.allocate(4).order(DEFAULT_BYTE_ORDER).putInt(key).array();
 byte[] length = ByteBuffer.allocate(4).order(DEFAULT_BYTE_ORDER).putInt(bytes.length).array();
 System.arraycopy(type, 0, result, offset, type.length);
 offset += 4;
 System.arraycopy(length, 0, result, offset, length.length);
 offset += 4;
 System.arraycopy(bytes, 0, result, offset, bytes.length);
 offset += bytes.length;
 }
 return result;
 }
 
 public void putByteValue(int type, byte value) {
 byte[] bytes = new byte[1]; 
 bytes[0] = value;
 putBytesValue(type, bytes);
 }
 
 public void putShortValue(int type, short value) {
 byte[] bytes = ByteBuffer.allocate(2).order(DEFAULT_BYTE_ORDER).putShort(value).array();
 putBytesValue(type, bytes);
 }
 
 public void putIntValue(int type, int value) {
 byte[] bytes = ByteBuffer.allocate(4).order(DEFAULT_BYTE_ORDER).putInt(value).array();
 putBytesValue(type, bytes);
 }
 
 public void putLongValue(int type, long value) {
 byte[] bytes = ByteBuffer.allocate(8).order(DEFAULT_BYTE_ORDER).putLong(value).array();
 putBytesValue(type, bytes);
 }
 
 public void putFloatValue(int type, float value) {
 byte[] bytes = ByteBuffer.allocate(4).order(DEFAULT_BYTE_ORDER).putFloat(value).array();
 putBytesValue(type, bytes);
 }
 
 public void putDoubleValue(int type, double value) {
 byte[] bytes = ByteBuffer.allocate(8).order(DEFAULT_BYTE_ORDER).putDouble(value).array();
 putBytesValue(type, bytes);
 }
 
 public void putStringValue(int type, String value) { 
 putBytesValue(type, value.getBytes()); 
 }

 public void putObjectValue(int type, TlvBox value) { 
 putBytesValue(type, value.serialize());
 }
 
 public void putBytesValue(int type, byte[] value) {
 mObjects.put(type, value);
 mTotalBytes += value.length + 8;
 }
 
 public Byte getByteValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return bytes[0];
 }
 
 public Short getShortValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return ByteBuffer.wrap(bytes).order(DEFAULT_BYTE_ORDER).getShort();
 }
 
 public Integer getIntValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return ByteBuffer.wrap(bytes).order(DEFAULT_BYTE_ORDER).getInt();
 }
 
 public Long getLongValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return ByteBuffer.wrap(bytes).order(DEFAULT_BYTE_ORDER).getLong();
 }
 
 public Float getFloatValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return ByteBuffer.wrap(bytes).order(DEFAULT_BYTE_ORDER).getFloat();
 }
 
 public Double getDoubleValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return ByteBuffer.wrap(bytes).order(DEFAULT_BYTE_ORDER).getDouble();
 }
 
 public TlvBox getObjectValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return TlvBox.parse(bytes, 0, bytes.length);
 }
 
 public String getStringValue(int type) {
 byte[] bytes = mObjects.get(type);
 if (bytes == null) {
 return null;
 }
 return new String(bytes).trim();
 }
 
 public byte[] getBytesValue(int type) {
 byte[] bytes = mObjects.get(type);
 return bytes;
 }
}