#include <cstdio>
#include <ctime>
#include <algorithm>

#include "ImageIO.h"

using namespace std;

#define ITERATION_COUNT 100

// ugyanaz a számítás csak a CPU-n.
void smoothOnCPU(float* dst, float* src, int w, int h);

//------------------------------------------------------------------------------
// main
int main()
{
    int i, j;
    unsigned int time;

    unsigned char* image;
    int h, w;

    readRGBImageFromFile("Lena.png", image, w, h);

    time = clock();

    float* temp_src = new float[w * h * 4 * sizeof(float)];
    float* temp_dst = new float[w * h * 4 * sizeof(float)];

    printf("Kep beolvasva: %d s\n", clock()-time);

    for(i=0; i<w*h*4; i++) {
        temp_src[i] = image[i];
    }

    printf("Kep konvertalva es elokeszitese: %d s\n", clock()-time);

    for(i=0; i<1000; i++) {
        if(i%2) {
            smoothOnCPU(temp_src, temp_dst, w, h);
        } else {
            smoothOnCPU(temp_dst, temp_src, w, h);
        }
    }

    printf("Iterativ simitas kesz: %d s\n", clock()-time);

    printf("Kep visszalakitva: %d s\n", clock()-time);

    for(i=0; i<w*h*4; i++) {
        image[i] = temp_src[i];
    }

    writeRGBImageToFile("out.png", image, w, h);

    return 0;
}

void smoothOnCPU(float* dst, float* src, int w, int h) {
    int x, y, i, j;

    float temp_r;
    float temp_g;
    float temp_b;
    int counter;

    for(y=0; y<h; y++) {
        for(x=0; x<w; x++) {
            temp_r = 0;
            temp_g = 0;
            temp_b = 0;
            counter = 0;
            for(i=-1; i<2; i++) {
                for(j=-1; j<2; j++) {
                    if(y+i>=0 && y+i<h && x+j>=0 && x+j<w) {
                        temp_r += src[4*((y+i)*w + x+j) + 0];
                        temp_g += src[4*((y+i)*w + x+j) + 1];
                        temp_b += src[4*((y+i)*w + x+j) + 2];
                        counter++;
                    }
                }
            }
            dst[4*(y*w+x) + 0] = temp_r / counter;
            dst[4*(y*w+x) + 1] = temp_g / counter;
            dst[4*(y*w+x) + 2] = temp_b / counter;
        }
    }

    return;
}