#include "Image_Exporter.h"


//extern int _options;	// Global options settings variable

int saveToPNG(RS_IMAGE *img, char *tex_path, char *hmt_fileName) {
	if (tex_path == NULL || img == NULL) return EXIT_FAILURE;
	char export_path[128];
	FILE *_png_f = NULL;
	png_structp png_ptr = NULL;
	png_infop info_ptr = NULL;
	size_t x,y;
	png_byte **row_ptrs = NULL;
	PIXEL_A *pixel = NULL;
	//int pixel_size = 3;
	//int depth = 8;		//bit par color channel (RGB)

	strcpy(export_path, hmt_fileName);
	#ifdef _WIN32
		strcat(export_path, "-out\\");
	#else
		strcat(export_path, "-out/");
	#endif
	strcat(export_path, tex_path);
	strcat(export_path, ".png");
	_png_f = fopen(export_path, "wb");
	if (_png_f == NULL) return EXIT_FAILURE;
	png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
	if (png_ptr == NULL) {
		fclose(_png_f);
		return EXIT_FAILURE;
	}
	info_ptr = png_create_info_struct(png_ptr);
	if (info_ptr == NULL) {
		fclose(_png_f);
		return EXIT_FAILURE;
	}

	// Set image attributes
	png_set_IHDR(png_ptr, info_ptr, img->width, img->height, 8, PNG_COLOR_TYPE_RGBA, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);

	// Init PNG datas
	row_ptrs = png_malloc(png_ptr, img->height * sizeof(png_byte *));
	for (y=0; y<img->height; y++) {
		png_byte *row = png_malloc(png_ptr, img->width*sizeof(PIXEL_A));
		row_ptrs[y] = row;
		for (x=0; x<img->width; x++) {
			pixel = pixelAt(img, x , y);
			if(pixel == NULL) return EXIT_FAILURE;

			*row++ = pixel->_red;
			*row++ = pixel->_green;
			*row++ = pixel->_blue;
			*row++ = pixel->_alpha;
		}
	}

	png_init_io(png_ptr, _png_f);
	png_set_rows(png_ptr, info_ptr, row_ptrs);
	png_write_png(png_ptr, info_ptr, PNG_TRANSFORM_IDENTITY, NULL);

	for (y=0; y<img->height; y++) {
		png_free(png_ptr, row_ptrs[y]);
	}
	png_free(png_ptr, row_ptrs);
	png_destroy_write_struct(&png_ptr, &info_ptr);
	fclose(_png_f);

	return EXIT_SUCCESS;
}