/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Copyright 2011, Blender Foundation.
 */

#include "COM_GaussianBokehBlurOperation.h"
#include "BLI_math.h"
#include "MEM_guardedalloc.h"

#include "RE_pipeline.h"

GaussianBokehBlurOperation::GaussianBokehBlurOperation() : BlurBaseOperation(COM_DT_COLOR)
{
  this->m_gausstab = nullptr;
}

void *GaussianBokehBlurOperation::initializeTileData(rcti * /*rect*/)
{
  lockMutex();
  if (!this->m_sizeavailable) {
    updateGauss();
  }
  void *buffer = getInputOperation(0)->initializeTileData(nullptr);
  unlockMutex();
  return buffer;
}

void GaussianBokehBlurOperation::initExecution()
{
  BlurBaseOperation::initExecution();

  initMutex();

  if (this->m_sizeavailable) {
    updateGauss();
  }
}

void GaussianBokehBlurOperation::updateGauss()
{
  if (this->m_gausstab == nullptr) {
    float radxf;
    float radyf;
    int n;
    float *dgauss;
    float *ddgauss;
    int j, i;
    const float width = this->getWidth();
    const float height = this->getHeight();
    if (!this->m_sizeavailable) {
      updateSize();
    }
    radxf = this->m_size * (float)this->m_data.sizex;
    CLAMP(radxf, 0.0f, width / 2.0f);

    /* vertical */
    radyf = this->m_size * (float)this->m_data.sizey;
    CLAMP(radyf, 0.0f, height / 2.0f);

    this->m_radx = ceil(radxf);
    this->m_rady = ceil(radyf);

    int ddwidth = 2 * this->m_radx + 1;
    int ddheight = 2 * this->m_rady + 1;
    n = ddwidth * ddheight;

    /* create a full filter image */
    ddgauss = (float *)MEM_mallocN(sizeof(float) * n, __func__);
    dgauss = ddgauss;
    float sum = 0.0f;
    float facx = (radxf > 0.0f ? 1.0f / radxf : 0.0f);
    float facy = (radyf > 0.0f ? 1.0f / radyf : 0.0f);
    for (j = -this->m_rady; j <= this->m_rady; j++) {
      for (i = -this->m_radx; i <= this->m_radx; i++, dgauss++) {
        float fj = (float)j * facy;
        float fi = (float)i * facx;
        float dist = sqrt(fj * fj + fi * fi);
        *dgauss = RE_filter_value(this->m_data.filtertype, dist);

        sum += *dgauss;
      }
    }

    if (sum > 0.0f) {
      /* normalize */
      float norm = 1.0f / sum;
      for (j = n - 1; j >= 0; j--) {
        ddgauss[j] *= norm;
      }
    }
    else {
      int center = m_rady * ddwidth + m_radx;
      ddgauss[center] = 1.0f;
    }

    this->m_gausstab = ddgauss;
  }
}

void GaussianBokehBlurOperation::executePixel(float output[4], int x, int y, void *data)
{
  float tempColor[4];
  tempColor[0] = 0;
  tempColor[1] = 0;
  tempColor[2] = 0;
  tempColor[3] = 0;
  float multiplier_accum = 0;
  MemoryBuffer *inputBuffer = (MemoryBuffer *)data;
  float *buffer = inputBuffer->getBuffer();
  int bufferwidth = inputBuffer->getWidth();
  int bufferstartx = inputBuffer->getRect()->xmin;
  int bufferstarty = inputBuffer->getRect()->ymin;

  rcti &rect = *inputBuffer->getRect();
  int ymin = max_ii(y - this->m_rady, rect.ymin);
  int ymax = min_ii(y + this->m_rady + 1, rect.ymax);
  int xmin = max_ii(x - this->m_radx, rect.xmin);
  int xmax = min_ii(x + this->m_radx + 1, rect.xmax);

  int index;
  int step = QualityStepHelper::getStep();
  int offsetadd = QualityStepHelper::getOffsetAdd();
  const int addConst = (xmin - x + this->m_radx);
  const int mulConst = (this->m_radx * 2 + 1);
  for (int ny = ymin; ny < ymax; ny += step) {
    index = ((ny - y) + this->m_rady) * mulConst + addConst;
    int bufferindex = ((xmin - bufferstartx) * 4) + ((ny - bufferstarty) * 4 * bufferwidth);
    for (int nx = xmin; nx < xmax; nx += step) {
      const float multiplier = this->m_gausstab[index];
      madd_v4_v4fl(tempColor, &buffer[bufferindex], multiplier);
      multiplier_accum += multiplier;
      index += step;
      bufferindex += offsetadd;
    }
  }

  mul_v4_v4fl(output, tempColor, 1.0f / multiplier_accum);
}

void GaussianBokehBlurOperation::deinitExecution()
{
  BlurBaseOperation::deinitExecution();

  if (this->m_gausstab) {
    MEM_freeN(this->m_gausstab);
    this->m_gausstab = nullptr;
  }

  deinitMutex();
}

bool GaussianBokehBlurOperation::determineDependingAreaOfInterest(
    rcti *input, ReadBufferOperation *readOperation, rcti *output)
{
  rcti newInput;
  rcti sizeInput;
  sizeInput.xmin = 0;
  sizeInput.ymin = 0;
  sizeInput.xmax = 5;
  sizeInput.ymax = 5;
  NodeOperation *operation = this->getInputOperation(1);

  if (operation->determineDependingAreaOfInterest(&sizeInput, readOperation, output)) {
    return true;
  }

  if (this->m_sizeavailable && this->m_gausstab != nullptr) {
    newInput.xmin = 0;
    newInput.ymin = 0;
    newInput.xmax = this->getWidth();
    newInput.ymax = this->getHeight();
  }
  else {
    int addx = this->m_radx;
    int addy = this->m_rady;
    newInput.xmax = input->xmax + addx;
    newInput.xmin = input->xmin - addx;
    newInput.ymax = input->ymax + addy;
    newInput.ymin = input->ymin - addy;
  }
  return BlurBaseOperation::determineDependingAreaOfInterest(&newInput, readOperation, output);
}

// reference image
GaussianBlurReferenceOperation::GaussianBlurReferenceOperation() : BlurBaseOperation(COM_DT_COLOR)
{
  this->m_maintabs = nullptr;
}

void *GaussianBlurReferenceOperation::initializeTileData(rcti * /*rect*/)
{
  void *buffer = getInputOperation(0)->initializeTileData(nullptr);
  return buffer;
}

void GaussianBlurReferenceOperation::initExecution()
{
  BlurBaseOperation::initExecution();
  // setup gaustab
  this->m_data.image_in_width = this->getWidth();
  this->m_data.image_in_height = this->getHeight();
  if (this->m_data.relative) {
    switch (this->m_data.aspect) {
      case CMP_NODE_BLUR_ASPECT_NONE:
        this->m_data.sizex = (int)(this->m_data.percentx * 0.01f * this->m_data.image_in_width);
        this->m_data.sizey = (int)(this->m_data.percenty * 0.01f * this->m_data.image_in_height);
        break;
      case CMP_NODE_BLUR_ASPECT_Y:
        this->m_data.sizex = (int)(this->m_data.percentx * 0.01f * this->m_data.image_in_width);
        this->m_data.sizey = (int)(this->m_data.percenty * 0.01f * this->m_data.image_in_width);
        break;
      case CMP_NODE_BLUR_ASPECT_X:
        this->m_data.sizex = (int)(this->m_data.percentx * 0.01f * this->m_data.image_in_height);
        this->m_data.sizey = (int)(this->m_data.percenty * 0.01f * this->m_data.image_in_height);
        break;
    }
  }

  /* horizontal */
  m_filtersizex = (float)this->m_data.sizex;
  int imgx = getWidth() / 2;
  if (m_filtersizex > imgx) {
    m_filtersizex = imgx;
  }
  else if (m_filtersizex < 1) {
    m_filtersizex = 1;
  }
  m_radx = (float)m_filtersizex;

  /* vertical */
  m_filtersizey = (float)this->m_data.sizey;
  int imgy = getHeight() / 2;
  if (m_filtersizey > imgy) {
    m_filtersizey = imgy;
  }
  else if (m_filtersizey < 1) {
    m_filtersizey = 1;
  }
  m_rady = (float)m_filtersizey;
  updateGauss();
}

void GaussianBlurReferenceOperation::updateGauss()
{
  int i;
  int x = max(m_filtersizex, m_filtersizey);
  m_maintabs = (float **)MEM_mallocN(x * sizeof(float *), "gauss array");
  for (i = 0; i < x; i++) {
    m_maintabs[i] = make_gausstab(i + 1, i + 1);
  }
}

void GaussianBlurReferenceOperation::executePixel(float output[4], int x, int y, void *data)
{
  MemoryBuffer *memorybuffer = (MemoryBuffer *)data;
  float *buffer = memorybuffer->getBuffer();
  float *gausstabx, *gausstabcenty;
  float *gausstaby, *gausstabcentx;
  int i, j;
  float *src;
  float sum, val;
  float rval, gval, bval, aval;
  int imgx = getWidth();
  int imgy = getHeight();
  float tempSize[4];
  this->m_inputSize->read(tempSize, x, y, data);
  float refSize = tempSize[0];
  int refradx = (int)(refSize * m_radx);
  int refrady = (int)(refSize * m_rady);
  if (refradx > m_filtersizex) {
    refradx = m_filtersizex;
  }
  else if (refradx < 1) {
    refradx = 1;
  }
  if (refrady > m_filtersizey) {
    refrady = m_filtersizey;
  }
  else if (refrady < 1) {
    refrady = 1;
  }

  if (refradx == 1 && refrady == 1) {
    memorybuffer->readNoCheck(output, x, y);
  }
  else {
    int minxr = x - refradx < 0 ? -x : -refradx;
    int maxxr = x + refradx > imgx ? imgx - x : refradx;
    int minyr = y - refrady < 0 ? -y : -refrady;
    int maxyr = y + refrady > imgy ? imgy - y : refrady;

    float *srcd = buffer + COM_NUM_CHANNELS_COLOR * ((y + minyr) * imgx + x + minxr);

    gausstabx = m_maintabs[refradx - 1];
    gausstabcentx = gausstabx + refradx;
    gausstaby = m_maintabs[refrady - 1];
    gausstabcenty = gausstaby + refrady;

    sum = gval = rval = bval = aval = 0.0f;
    for (i = minyr; i < maxyr; i++, srcd += COM_NUM_CHANNELS_COLOR * imgx) {
      src = srcd;
      for (j = minxr; j < maxxr; j++, src += COM_NUM_CHANNELS_COLOR) {

        val = gausstabcenty[i] * gausstabcentx[j];
        sum += val;
        rval += val * src[0];
        gval += val * src[1];
        bval += val * src[2];
        aval += val * src[3];
      }
    }
    sum = 1.0f / sum;
    output[0] = rval * sum;
    output[1] = gval * sum;
    output[2] = bval * sum;
    output[3] = aval * sum;
  }
}

void GaussianBlurReferenceOperation::deinitExecution()
{
  int x, i;
  x = max(this->m_filtersizex, this->m_filtersizey);
  for (i = 0; i < x; i++) {
    MEM_freeN(this->m_maintabs[i]);
  }
  MEM_freeN(this->m_maintabs);
  BlurBaseOperation::deinitExecution();
}

bool GaussianBlurReferenceOperation::determineDependingAreaOfInterest(
    rcti *input, ReadBufferOperation *readOperation, rcti *output)
{
  rcti newInput;
  NodeOperation *operation = this->getInputOperation(1);

  if (operation->determineDependingAreaOfInterest(input, readOperation, output)) {
    return true;
  }

  int addx = this->m_data.sizex + 2;
  int addy = this->m_data.sizey + 2;
  newInput.xmax = input->xmax + addx;
  newInput.xmin = input->xmin - addx;
  newInput.ymax = input->ymax + addy;
  newInput.ymin = input->ymin - addy;
  return NodeOperation::determineDependingAreaOfInterest(&newInput, readOperation, output);
}
