#include <cmath>     // pow(-)</cmath>

#include <stdexcept> /* std::domain_error(-) */</stdexcept>

#include <limits>    // std::numeric_limits</limits>

#include <vector></vector>

#include "igs_level_auto.h"

#include "igs_ifx_common.h" /* igs::image::rgba */

//------------------------------------------------------------

namespace {

double level_value_(double value, double mul_max, bool act_sw, double in_min,

                    double in_max, double out_min, double out_max,

                    double gamma) {

  if (act_sw) {

    if (in_max == in_min) {

      value = in_max;

    } else {

      /* 制限(in_min〜in_max) */

      if (in_min < in_max) {

        if (value < in_min) {

          value = in_min;

        } else if (in_max < value) {

          value = in_max;

        }

      } else {

        if (value < in_max) {

          value = in_max;

        } else if (in_min < value) {

          value = in_min;

        }

      }

      /* 正規化(0〜1) */

      value = (value - in_min) / (in_max - in_min);

      /* Gamma変換 */

      if ((1.0 != gamma) && (0.0 != gamma)) {

        value = pow(value, 1.0 / gamma);

      }

    }

    /* Outputの範囲にスケール変換 */

    value = out_min + value * (out_max - out_min);

    /* 0...1の間で制限かける */

    if (value < 0.0) {

      value = 0.0;

    } else if (1.0 < value) {

      value = 1.0;

    }

  }

  /* 0〜1.0 --> 0〜mul_maxスケール変換し、整数値化 */

  return floor(value * mul_max);

}

//------------------------------------------------------------

void level_ctable_template_(const unsigned int channels,

                            const bool *act_sw,          // user setting

                            const int *in_min,           // image pixel value

                            const int *in_max,           // image pixel value

                            const double *in_min_shift,  // user settting

                            const double *in_max_shift,  // user settting

                            const double *out_min,       // user settting

                            const double *out_max,       // user settting

                            const double *gamma,         // user settting

                            const unsigned int div_num,

                            std::vector<std::vector<unsigned int="">> &table_array</std::vector<unsigned>

                            /*

                            std::vector< std::vector<t> > &table_array</t>

                     とするとvc2005mdで他プログラムとのリンク時、

                            allocatorの２重定義でエラーとなる。

                            std::vector< std::vector<unsigned int=""> >&table_array</unsigned>

                     ならOK

                     2009-01-27

                    */

                            ) {

  const double div_val = static_cast<double>(div_num);</double>

  const double mul_val = div_val + 0.999999;

#if defined _WIN32  // vc compile_type

  double in_min_[4], in_max_[4];

#else

  double in_min_[channels], in_max_[channels];

#endif

  for (unsigned int cc = 0; cc < channels; ++cc) {

    in_min_[cc] = in_min_shift[cc] + in_min[cc] / div_val;

    in_max_[cc] = in_max_shift[cc] + in_max[cc] / div_val;

  }

  table_array.resize(channels);

  for (unsigned int cc = 0; cc < channels; ++cc) {

    table_array[cc].resize(div_num + 1);

    for (unsigned int yy = 0; yy <= div_num; ++yy) {

      table_array[cc][yy] = static_cast<unsigned int="">(</unsigned>

          level_value_(yy / div_val, mul_val, act_sw[cc], in_min_[cc],

                       in_max_[cc], out_min[cc], out_max[cc], gamma[cc]));

    }

  }

}

//------------------------------------------------------------

template <class t=""></class>

void change_template_(T *image_array, const int height, const int width,

                      const int channels,

                      const bool *act_sw, const double *in_min_shift,

                      const double *in_max_shift, const double *out_min,

                      const double *out_max, const double *gamma) {

/* 1.まず最大値、最小値を求める */

#if defined _WIN32

  int in_min[4], in_max[4];

#else

  int in_min[channels], in_max[channels];

#endif

  for (int zz = 0; zz < channels; ++zz) {

    in_min[zz] = in_max[zz] = image_array[zz];

  }

  T *image_crnt = image_array;

  for (int yy = 0; yy < height; ++yy) {

    for (int xx = 0; xx < width; ++xx) {

      for (int zz = 0; zz < channels; ++zz) {

        if (image_crnt[zz] < in_min[zz]) {

          in_min[zz] = image_crnt[zz];

        } else if (in_max[zz] < image_crnt[zz]) {

          in_max[zz] = image_crnt[zz];

        }

      }

      image_crnt += channels;

    }

  }

  /* 2.最大値、最小値から変換テーブルを求める */

  std::vector<std::vector<unsigned int="">> table_array;</std::vector<unsigned>

  level_ctable_template_(channels, act_sw, in_min, in_max, in_min_shift,

                         in_max_shift, out_min, out_max, gamma,

                         std::numeric_limits<t>::max(), table_array);</t>

  /* 3.変換テーブルを使ってlevel変換する */

  image_crnt        = image_array;

  const int pixsize = height * width;

  if (igs::image::rgba::siz == channels) {

    using namespace igs::image::rgba;

    for (int ii = 0; ii < pixsize; ++ii, image_crnt += channels) {

      image_crnt[red] = static_cast<t>(table_array[0][image_crnt[red]]);</t>

      image_crnt[gre] = static_cast<t>(table_array[1][image_crnt[gre]]);</t>

      image_crnt[blu] = static_cast<t>(table_array[2][image_crnt[blu]]);</t>

      image_crnt[alp] = static_cast<t>(table_array[3][image_crnt[alp]]);</t>

    }

  } else if (igs::image::rgb::siz == channels) {

    using namespace igs::image::rgb;

    for (int ii = 0; ii < pixsize; ++ii, image_crnt += channels) {

      image_crnt[red] = static_cast<t>(table_array[0][image_crnt[red]]);</t>

      image_crnt[gre] = static_cast<t>(table_array[1][image_crnt[gre]]);</t>

      image_crnt[blu] = static_cast<t>(table_array[2][image_crnt[blu]]);</t>

    }

  } else if (1 == channels) { /* grayscale */

    for (int ii = 0; ii < pixsize; ++ii, ++image_crnt) {

      image_crnt[0] = static_cast<t>(table_array[0][image_crnt[0]]);</t>

    }

  }

  table_array.clear();

}

}

void igs::level_auto::change(unsigned char *image_array,

                             const int height, const int width,

                             const int channels, const int bits,

                             const bool *act_sw,          // channels array

                             const double *in_min_shift,  // channels array

                             const double *in_max_shift,  // channels array

                             const double *out_min,       // channels array

                             const double *out_max,       // channels array

                             const double *gamma          // channels array

                             ) {

  if ((igs::image::rgba::siz != channels) &&

      (igs::image::rgb::siz != channels) && (1 != channels) /* grayscale */

      ) {

    throw std::domain_error("Bad channels,Not rgba/rgb/grayscale");

  }

  if (std::numeric_limits<unsigned char="">::digits == bits) {</unsigned>

    change_template_(image_array, height, width, channels, act_sw, in_min_shift,

                     in_max_shift, out_min, out_max, gamma);

  } else if (std::numeric_limits<unsigned short="">::digits == bits) {</unsigned>

    change_template_(reinterpret_cast<unsigned *="" short="">(image_array), height,</unsigned>

                     width, channels, act_sw, in_min_shift, in_max_shift,

                     out_min, out_max, gamma);

  } else {

    throw std::domain_error("Bad bits,Not uchar/ushort");

  }

}