// Copyright 2014 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
// Original code is licensed as follows:
/*
 * Copyright 2012 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "xfa/fxbarcode/pdf417/BC_PDF417Common.h"
#include "xfa/fxbarcode/pdf417/BC_PDF417ECModulusGF.h"
#include "xfa/fxbarcode/pdf417/BC_PDF417ECModulusPoly.h"
#include "xfa/fxbarcode/utils.h"

CBC_PDF417ECModulusGF* CBC_PDF417ECModulusGF::PDF417_GF = NULL;
void CBC_PDF417ECModulusGF::Initialize(int32_t& e) {
  PDF417_GF =
      new CBC_PDF417ECModulusGF(CBC_PDF417Common::NUMBER_OF_CODEWORDS, 3, e);
}
void CBC_PDF417ECModulusGF::Finalize() {
  delete PDF417_GF;
}
CBC_PDF417ECModulusGF::CBC_PDF417ECModulusGF(int32_t modulus,
                                             int32_t generator,
                                             int32_t& e) {
  m_modulus = modulus;
  m_expTable.SetSize(modulus);
  m_logTable.SetSize(modulus);
  int32_t x = 1;
  for (int32_t i = 0; i < modulus; i++) {
    m_expTable[i] = x;
    x = (x * generator) % modulus;
  }
  for (int32_t j = 0; j < modulus - 1; j++) {
    m_logTable[m_expTable[j]] = j;
  }
  CFX_Int32Array zero;
  zero.Add(0);
  m_zero = new CBC_PDF417ECModulusPoly(this, zero, e);
  CFX_Int32Array one;
  one.Add(1);
  m_one = new CBC_PDF417ECModulusPoly(this, one, e);
}
CBC_PDF417ECModulusGF::~CBC_PDF417ECModulusGF() {
  delete m_zero;
  delete m_one;
}
CBC_PDF417ECModulusPoly* CBC_PDF417ECModulusGF::getZero() {
  return m_zero;
}
CBC_PDF417ECModulusPoly* CBC_PDF417ECModulusGF::getOne() {
  return m_one;
}
CBC_PDF417ECModulusPoly* CBC_PDF417ECModulusGF::buildMonomial(
    int32_t degree,
    int32_t coefficient,
    int32_t& e) {
  if (degree < 0) {
    e = BCExceptionIllegalArgument;
    return NULL;
  }
  CBC_PDF417ECModulusPoly* modulusPoly = NULL;
  if (coefficient == 0) {
    modulusPoly = new CBC_PDF417ECModulusPoly(m_zero->getField(),
                                              m_zero->getCoefficients(), e);
    BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
    return modulusPoly;
  }
  CFX_Int32Array coefficients;
  coefficients.SetSize(degree + 1);
  coefficients[0] = coefficient;
  modulusPoly = new CBC_PDF417ECModulusPoly(this, coefficients, e);
  BC_EXCEPTION_CHECK_ReturnValue(e, NULL);
  return modulusPoly;
}
int32_t CBC_PDF417ECModulusGF::add(int32_t a, int32_t b) {
  return (a + b) % m_modulus;
}
int32_t CBC_PDF417ECModulusGF::subtract(int32_t a, int32_t b) {
  return (m_modulus + a - b) % m_modulus;
}
int32_t CBC_PDF417ECModulusGF::exp(int32_t a) {
  return m_expTable[a];
}
int32_t CBC_PDF417ECModulusGF::log(int32_t a, int32_t& e) {
  if (a == 0) {
    e = BCExceptionIllegalArgument;
    return -1;
  }
  return m_logTable[a];
}
int32_t CBC_PDF417ECModulusGF::inverse(int32_t a, int32_t& e) {
  if (a == 0) {
    e = BCExceptionIllegalArgument;
    return -1;
  }
  return m_expTable[m_modulus - m_logTable[a] - 1];
}
int32_t CBC_PDF417ECModulusGF::multiply(int32_t a, int32_t b) {
  if (a == 0 || b == 0) {
    return 0;
  }
  return m_expTable[(m_logTable[a] + m_logTable[b]) % (m_modulus - 1)];
}
int32_t CBC_PDF417ECModulusGF::getSize() {
  return m_modulus;
}