/*
   render/image.cc
   This file is part of the Osirion project and is distributed under
   the terms of the GNU General Public License version 2
*/

#include <string>

#include <cstdlib>
#include <cstring>

#include "sys/sys.h"

#include "render/image.h"
#include "render/tgafile.h"
#include "render/pngfile.h"
#include "render/jpgfile.h"

namespace render
{

Image::Image(unsigned int width, unsigned int height, unsigned int channels)
{
	image_width = width;
	image_height = height;
	image_channels = channels;

	image_data = (unsigned char *) malloc(size());
	clear();
}

Image::~Image()
{
	free(image_data);
}

void Image::clear()
{
	memset(image_data, 0, size());
}

void Image::swap_channels()
{
	for (size_t y = 0; y < image_height; y++) {
		for (size_t x = 0; x < image_width; x++) {
			size_t offset = y * image_width * image_channels + x * image_channels;
			unsigned char tmp = image_data[offset];
			image_data[offset] = image_data[offset + 2];
			image_data[offset + 2] = tmp;
		}
	}
}

void Image::pad()
{
	unsigned int w = width();
	unsigned int h = height();

	if ((w % 8) != 0) {
		image_width = w + (8 - (w % 8));
	}

	if ((w % 8) != 0) {
		image_height = h + (8 - (h % 8));
	}

	unsigned char *image_new = (unsigned char *) malloc(size());
	memset(image_new, 0, size());

	for (size_t y = 0; y < h; y++) {
		memcpy((void *)&image_new[y * image_width * image_channels],
		       (void *)&image_data[y * w * image_channels], (size_t) w);
	}

	free(image_data);
	image_data = image_new;
}

void Image::flip_vertical()
{
	unsigned char line[image_width*image_channels];
	for (size_t y = 0; y < image_height / 2; y++) {
		memcpy(line,
		       &image_data[y*image_width*image_channels],
		       image_width*image_channels);
		memcpy(&image_data[y*image_width*image_channels],
		       &image_data[(image_height-1-y)*image_width*image_channels],
		       image_width*image_channels);
		memcpy(&image_data[(image_height-1-y)*image_width*image_channels],
		       line,
		       image_width*image_channels);
	}
}

void Image::flip_horizontal()
{
	unsigned char pixel_data[image_channels];
	for (size_t y = 0; y < image_height; y++) {
		for (size_t x = 0; x < image_width / 2; x++) {
			void *src = pixel(x,y); // &image_data[(y * image_width + x) * image_channels];
			void *dst = pixel(image_width - x - 1, y); // (&image_data[((y+1) * image_width - x - 1) * image_channels];
			memcpy(pixel_data, dst, image_channels);
			memcpy(dst, src, image_channels);
			memcpy(src, pixel_data, image_channels);
		}
	}
}

Image *Image::load(const std::string & name)
{	
	std::string filename;
	Image *image = 0;

	if (!image) {
		// try the png version
		filename.assign(name);
		filename.append(".png");
		image = PNG::load(filename.c_str());
	}

	if (!image) {
		// try the tga version
		filename.assign(name);
		filename.append(".tga");
		image = TGA::load(filename.c_str());
	}

	if (!image) {
		// try the jpg version
		filename.assign(name);
		filename.append(".jpg");
		image = JPG::load(filename.c_str());
	}

	if (!image) {
		con_warn << "Could not open image " << name << std::endl;
		return 0;
	}
	
	return image;
}

}