#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libgen.h>
#include "../lib/imageio.h"

void tackName(char* fileAndPath, char* ending, char* dest);

int main(int argc,char * argv[]){
	
	if (argc != 3) {
		printf("Usage: intensity <file path> <intensity>\n");
		return -1;
	}
	
	IMAGE org = image_open(argv[1]);
	if (org == NULL) {
		printf("Failed to open file: %s\n", argv[1]);
		return -1;
	}
	
	float intensity = (float) atof(argv[2]);
	
	IMAGE clone = image_clone(org);
	if (clone == NULL) {
		printf("Failed to clone image.\n");
		return -1;
	}
	
	image_close(org);

	int width = image_width(clone);
	int height = image_height(clone);
	int size = width * height;
	int* pixels = image_pixels(clone);
	unsigned char* pixelChannel; // = pixels[0] + 1;
	
	// 0xAABBGGRR
	for (int i = 0; i < size; i++) {
		//pixelChannel = (unsigned char*) (&pixels + i);
		for (int j = 0; j < 3; j++) { // BB, GG, RR...
			pixelChannel = (unsigned char*) (&pixels[i]) + j; 
			// Skip alpha channel.
			//char temp = *pixelChannel;
			//*pixelChannel = (char) (*pixelChannel * intensity);
			//printf("%d * %f = %f or %d -> 0x%x\n", *pixelChannel, intensity, *pixelChannel * intensity, (unsigned char) (*pixelChannel * intensity), (unsigned char) (*pixelChannel * intensity));
			if ( (float) *pixelChannel * intensity > 0xFF) {
				*pixelChannel = 0xFF; // Cap it.
			} else {
				*pixelChannel = (unsigned char) (*pixelChannel * intensity);
			}
			
			//printf("{%d/%d}[%p]: %d -> %d\n", i, size, pixelChannel, temp, *pixelChannel);
		}
	}

	char fileStr[strlen(argv[1]) + 8];
	tackName(argv[1], "_int.jpg", fileStr);
	if (image_save(clone, fileStr)) {
		printf("Failure while saving image.\n");
		return -1;
	}
	image_close(clone);

	return 0;
}

void tackName(char* fileAndPath, char* ending, char* dest) {
	int index;

	char* file = basename(fileAndPath);

	for (index = strlen(file) - 1; index > 0; index--) {
		if (file[index] == '.') {
			break;
		}
	}

	strncpy(dest, file, index);
	dest[index] = '\0';
	strcat(dest, ending);
}