/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsBidiUtils.h"

#define ARABIC_TO_HINDI_DIGIT_INCREMENT \
  (START_HINDI_DIGITS - START_ARABIC_DIGITS)
#define PERSIAN_TO_HINDI_DIGIT_INCREMENT \
  (START_HINDI_DIGITS - START_FARSI_DIGITS)
#define ARABIC_TO_PERSIAN_DIGIT_INCREMENT \
  (START_FARSI_DIGITS - START_ARABIC_DIGITS)
#define NUM_TO_ARABIC(c)                                             \
  ((((c) >= START_HINDI_DIGITS) && ((c) <= END_HINDI_DIGITS))        \
       ? ((c) - (uint16_t)ARABIC_TO_HINDI_DIGIT_INCREMENT)           \
       : ((((c) >= START_FARSI_DIGITS) && ((c) <= END_FARSI_DIGITS)) \
              ? ((c) - (uint16_t)ARABIC_TO_PERSIAN_DIGIT_INCREMENT)  \
              : (c)))
#define NUM_TO_HINDI(c)                                              \
  ((((c) >= START_ARABIC_DIGITS) && ((c) <= END_ARABIC_DIGITS))      \
       ? ((c) + (uint16_t)ARABIC_TO_HINDI_DIGIT_INCREMENT)           \
       : ((((c) >= START_FARSI_DIGITS) && ((c) <= END_FARSI_DIGITS)) \
              ? ((c) + (uint16_t)PERSIAN_TO_HINDI_DIGIT_INCREMENT)   \
              : (c)))
#define NUM_TO_PERSIAN(c)                                              \
  ((((c) >= START_HINDI_DIGITS) && ((c) <= END_HINDI_DIGITS))          \
       ? ((c) - (uint16_t)PERSIAN_TO_HINDI_DIGIT_INCREMENT)            \
       : ((((c) >= START_ARABIC_DIGITS) && ((c) <= END_ARABIC_DIGITS)) \
              ? ((c) + (uint16_t)ARABIC_TO_PERSIAN_DIGIT_INCREMENT)    \
              : (c)))

char16_t HandleNumberInChar(char16_t aChar, bool aPrevCharArabic,
                            uint32_t aNumFlag) {
  // IBMBIDI_NUMERAL_NOMINAL *
  // IBMBIDI_NUMERAL_REGULAR
  // IBMBIDI_NUMERAL_HINDICONTEXT
  // IBMBIDI_NUMERAL_ARABIC
  // IBMBIDI_NUMERAL_HINDI

  switch (aNumFlag) {
    case IBMBIDI_NUMERAL_HINDI:
      return NUM_TO_HINDI(aChar);
    case IBMBIDI_NUMERAL_ARABIC:
      return NUM_TO_ARABIC(aChar);
    case IBMBIDI_NUMERAL_PERSIAN:
      return NUM_TO_PERSIAN(aChar);
    case IBMBIDI_NUMERAL_REGULAR:
    case IBMBIDI_NUMERAL_HINDICONTEXT:
    case IBMBIDI_NUMERAL_PERSIANCONTEXT:
      // for clipboard handling
      // XXX do we really want to convert numerals when copying text?
      if (aPrevCharArabic) {
        return aNumFlag == IBMBIDI_NUMERAL_PERSIANCONTEXT
                   ? NUM_TO_PERSIAN(aChar)
                   : NUM_TO_HINDI(aChar);
      }
      return NUM_TO_ARABIC(aChar);
    case IBMBIDI_NUMERAL_NOMINAL:
    default:
      return aChar;
  }
}

nsresult HandleNumbers(char16_t* aBuffer, uint32_t aSize, uint32_t aNumFlag) {
  uint32_t i;

  switch (aNumFlag) {
    case IBMBIDI_NUMERAL_HINDI:
    case IBMBIDI_NUMERAL_ARABIC:
    case IBMBIDI_NUMERAL_PERSIAN:
    case IBMBIDI_NUMERAL_REGULAR:
    case IBMBIDI_NUMERAL_HINDICONTEXT:
    case IBMBIDI_NUMERAL_PERSIANCONTEXT:
      for (i = 0; i < aSize; i++)
        aBuffer[i] = HandleNumberInChar(
            aBuffer[i], !!(i > 0 ? aBuffer[i - 1] : 0), aNumFlag);
      break;
    case IBMBIDI_NUMERAL_NOMINAL:
    default:
      break;
  }
  return NS_OK;
}