/*
 * Copyright 2011, Blender Foundation.
 *
 * 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.
 *
 * Contributor: 
 *		Jeroen Bakker 
 *		Monique Dewanchand
 */

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

extern "C" {
	#include "RE_pipeline.h"
}

GaussianBokehBlurOperation::GaussianBokehBlurOperation(): BlurBaseOperation() {
	this->gausstab = NULL;
}

void* GaussianBokehBlurOperation::initializeTileData(rcti *rect, MemoryBuffer **memoryBuffers) {
	updateGauss(memoryBuffers);
	void* buffer = getInputOperation(0)->initializeTileData(NULL, memoryBuffers);
	return buffer;
}

void GaussianBokehBlurOperation::updateGauss(MemoryBuffer **memoryBuffers) {
	if (this->gausstab == NULL) {
		float radxf;
		float radyf;
		int n;
		float* dgauss;
		float* ddgauss;
		float val;
		int j, i;
		const float width = this->getWidth();
		const float height = this->getHeight();
		updateSize(memoryBuffers);
		
		radxf = size*(float)this->data->sizex;
		if (radxf>width/2.0f)
			radxf= width/2.0f;
		else if (radxf<1.0f)
			radxf= 1.0f;
	
		/* vertical */
		radyf = size*(float)this->data->sizey;
		if (radyf>height/2.0f)
			radyf= height/2.0f;
		else if (radyf<1.0f)
			radyf= 1.0f;
	
		radx= ceil(radxf);
		rady= ceil(radyf);
	
		n = (2*radx+1)*(2*rady+1);
	
		/* create a full filter image */
		ddgauss= new float[n];
		dgauss= ddgauss;
		val= 0.0f;
		for (j=-rady; j<=rady; j++) {
			for (i=-radx; i<=radx; i++, dgauss++) {
				float fj= (float)j/radyf;
				float fi= (float)i/radxf;
				float dist= sqrt(fj*fj + fi*fi);
				*dgauss= RE_filter_value(this->data->filtertype, dist);
				
				val+= *dgauss;
			}
		}
		if (val!=0.0f) {
			val= 1.0f/val;
			for (j= n -1; j>=0; j--)
				ddgauss[j]*= val;
		}
		else ddgauss[4]= 1.0f;
		
		gausstab = ddgauss;
	}
}

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

	int miny = y - this->rady;
	int maxy = y + this->rady;
	int minx = x - this->radx;
	int maxx = x + this->radx;
	miny = max(miny, inputBuffer->getRect()->ymin);
	minx = max(minx, inputBuffer->getRect()->xmin);
	maxy = min(maxy, inputBuffer->getRect()->ymax);
	maxx = min(maxx, inputBuffer->getRect()->xmax);

	int index = 0;
	int step = QualityStepHelper::getStep();
	int offsetadd = QualityStepHelper::getOffsetAdd();
	for (int ny = miny ; ny < maxy ; ny +=step) {
		int bufferindex = ((minx - bufferstartx)*4)+((ny-bufferstarty)*4*bufferwidth);
		for (int nx = minx ; nx < maxx ; nx +=step) {
			float multiplyer = gausstab[index];
			tempColor[0] += multiplyer * buffer[bufferindex];
			tempColor[1] += multiplyer * buffer[bufferindex+1];
			tempColor[2] += multiplyer * buffer[bufferindex+2];
			tempColor[3] += multiplyer * buffer[bufferindex+3];
			overallmultiplyer += multiplyer;
			index += step;
			bufferindex +=offsetadd;
		}
	}
	float divider = 1.0/overallmultiplyer;
	color[0] = tempColor[0]*divider;
	color[1] = tempColor[1]*divider;
	color[2] = tempColor[2]*divider;
	color[3] = tempColor[3]*divider;
}

void GaussianBokehBlurOperation::deinitExecution() {
	BlurBaseOperation::deinitExecution();
	delete this->gausstab;
	this->gausstab = NULL;
}

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;
	}
	else {
		if (this->gausstab) {
			int addx = radx;
			int addy = rady;
			newInput.xmax = input->xmax + addx;
			newInput.xmin = input->xmin - addx;
			newInput.ymax = input->ymax + addy;
			newInput.ymin = input->ymin - addy;
		}
		else {
			newInput.xmin = 0;
			newInput.ymin = 0;
			newInput.xmax = this->getWidth();
			newInput.ymax = this->getHeight();
		}
		return BlurBaseOperation::determineDependingAreaOfInterest(&newInput, readOperation, output);
	}
}