package org.jcodec.algo;

import org.jcodec.api.NotSupportedException;

public class DataConvert {
  public static int[] from16BE(byte[] b) {
    int[] result = new int[b.length >> 1];
    int off = 0;
    for (int i = 0; i < result.length; i++)
      result[i] = (b[off++] & 0xFF) << 8 | b[off++] & 0xFF; 
    return result;
  }
  
  public static int[] from24BE(byte[] b) {
    int[] result = new int[b.length / 3];
    int off = 0;
    for (int i = 0; i < result.length; i++)
      result[i] = (b[off++] & 0xFF) << 16 | (b[off++] & 0xFF) << 8 | b[off++] & 0xFF; 
    return result;
  }
  
  public static int[] from16LE(byte[] b) {
    int[] result = new int[b.length >> 1];
    int off = 0;
    for (int i = 0; i < result.length; i++)
      result[i] = b[off++] & 0xFF | (b[off++] & 0xFF) << 8; 
    return result;
  }
  
  public static int[] from24LE(byte[] b) {
    int[] result = new int[b.length / 3];
    int off = 0;
    for (int i = 0; i < result.length; i++)
      result[i] = b[off++] & 0xFF | (b[off++] & 0xFF) << 8 | (b[off++] & 0xFF) << 16; 
    return result;
  }
  
  public static byte[] to16BE(int[] ia) {
    byte[] result = new byte[ia.length << 1];
    int off = 0;
    for (int i = 0; i < ia.length; i++) {
      result[off++] = (byte)(ia[i] >> 8 & 0xFF);
      result[off++] = (byte)(ia[i] & 0xFF);
    } 
    return result;
  }
  
  public static byte[] to24BE(int[] ia) {
    byte[] result = new byte[ia.length * 3];
    int off = 0;
    for (int i = 0; i < ia.length; i++) {
      result[off++] = (byte)(ia[i] >> 16 & 0xFF);
      result[off++] = (byte)(ia[i] >> 8 & 0xFF);
      result[off++] = (byte)(ia[i] & 0xFF);
    } 
    return result;
  }
  
  public static byte[] to16LE(int[] ia) {
    byte[] result = new byte[ia.length << 1];
    int off = 0;
    for (int i = 0; i < ia.length; i++) {
      result[off++] = (byte)(ia[i] & 0xFF);
      result[off++] = (byte)(ia[i] >> 8 & 0xFF);
    } 
    return result;
  }
  
  public static byte[] to24LE(int[] ia) {
    byte[] result = new byte[ia.length * 3];
    int off = 0;
    for (int i = 0; i < ia.length; i++) {
      result[off++] = (byte)(ia[i] & 0xFF);
      result[off++] = (byte)(ia[i] >> 8 & 0xFF);
      result[off++] = (byte)(ia[i] >> 16 & 0xFF);
    } 
    return result;
  }
  
  public static int[] fromByte(byte[] b, int depth, boolean isBe) {
    if (depth == 24) {
      if (isBe)
        return from24BE(b); 
      return from24LE(b);
    } 
    if (depth == 16) {
      if (isBe)
        return from16BE(b); 
      return from16LE(b);
    } 
    throw new NotSupportedException("Conversion from " + depth + "bit " + (
        isBe ? "big endian" : "little endian") + " is not supported.");
  }
  
  public static byte[] toByte(int[] ia, int depth, boolean isBe) {
    if (depth == 24) {
      if (isBe)
        return to24BE(ia); 
      return to24LE(ia);
    } 
    if (depth == 16) {
      if (isBe)
        return to16BE(ia); 
      return to16LE(ia);
    } 
    throw new NotSupportedException("Conversion to " + depth + "bit " + (isBe ? "big endian" : "little endian") + " is not supported.");
  }
}