///                  _ _
/// __  ___ __  _ __(_) |_ ___
/// \ \/ / '_ \| '__| | __/ _ \
///  >  <| |_) | |  | | ||  __/
/// /_/\_\ .__/|_|  |_|\__\___|
///      |_|
///
/// Copyright (c) 1997 - Ognjen 'xolatile' Milan Robovic
///
/// xolatile@chud.cyou - xprite - Custom file format for semi-efficient and very fast encoding and decoding of simple images.
///
/// This program is free software, free as in freedom and as in free beer, 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 3 of the License, or any later version if you wish...
///
/// This program is distributed in the hope that it will be useful, but it is probably not, and without any warranty, without even the implied
/// warranty of merchantability or fitness for a particular purpose, because it is pointless. Please see the GNU (Geenoo) General Public License
/// for more details, if you dare, it is a lot of text that nobody wants to read...

static unsigned int sprite_colour [128] = {
	0x00000000,     0xff222222,     0xff444444,     0xff666666,     0xff888888,     0xffaaaaaa,     0xffcccccc,     0xffeeeeee,
	0x11000000,     0xff000022,     0xff000044,     0xff000066,     0xff000088,     0xff0000aa,     0xff0000cc,     0xff0000ee,
	0x22000000,     0xff002200,     0xff004400,     0xff006600,     0xff008800,     0xff00aa00,     0xff00cc00,     0xff00ee00,
	0x33000000,     0xff220000,     0xff440000,     0xff660000,     0xff880000,     0xffaa0000,     0xffcc0000,     0xffee0000,
	0x44000000,     0xff002222,     0xff004444,     0xff006666,     0xff008888,     0xff00aaaa,     0xff00cccc,     0xff00eeee,
	0x55000000,     0xff222200,     0xff444400,     0xff666600,     0xff888800,     0xffaaaa00,     0xffcccc00,     0xffeeee00,
	0x66000000,     0xff220022,     0xff440044,     0xff660066,     0xff880088,     0xffaa00aa,     0xffcc00cc,     0xffee00ee,
	0x77000000,     0xff001122,     0xff002244,     0xff003366,     0xff004488,     0xff0055aa,     0xff0066cc,     0xff0077ee,
	0x88000000,     0xff110022,     0xff220044,     0xff330066,     0xff440088,     0xff5500aa,     0xff6600cc,     0xff7700ee,
	0x99000000,     0xff002211,     0xff004422,     0xff006633,     0xff008844,     0xff00aa55,     0xff00cc66,     0xff00ee77,
	0xaa000000,     0xff112200,     0xff224400,     0xff336600,     0xff448800,     0xff55aa00,     0xff66cc00,     0xff77ee00,
	0xbb000000,     0xff220011,     0xff440022,     0xff660033,     0xff880044,     0xffaa0055,     0xffcc0066,     0xffee0077,
	0xcc000000,     0xff221100,     0xff442200,     0xff663300,     0xff884400,     0xffaa5500,     0xffcc6600,     0xffee7700,
	0xdd000000,     0xff112222,     0xff224444,     0xff336666,     0xff448888,     0xff55aaaa,     0xff66cccc,     0xff77eeee,
	0xee000000,     0xff222211,     0xff444422,     0xff666633,     0xff888844,     0xffaaaa55,     0xffcccc66,     0xffeeee77,
	0xff000000,     0xff221122,     0xff442244,     0xff663366,     0xff884488,     0xffaa55aa,     0xffcc66cc,     0xffee77ee
};

static void * sprite_import (char * path, int * width, int * height) {
	unsigned char check_width  = 0;
	unsigned char check_height = 0;

	int file, move;

	unsigned int * data = null;

	file = file_open (path, file_flag_read);

	file_read (file, & check_width,  (int) sizeof (check_width));
	file_read (file, & check_height, (int) sizeof (check_height));

	* width  = (int) check_width;
	* height = (int) check_height;

	fatal_failure ((* width)  == 0, "sprite_import: Invalid sprite width.");
	fatal_failure ((* height) == 0, "sprite_import: Invalid sprite height.");

	data = allocate ((* width) * (* height) * (int) sizeof (* data));

	for (move = 0; move < (* width) * (* height); ++move) {
		int colour = 0;
		int repeat = 0;

		file_read (file, & colour, 1);

		if ((colour & 0x80) == 0) {
			data [move] = sprite_colour [colour];
		} else {
			int offset;

			file_read (file, & repeat, 1);

			colour &= 0x7f;
			repeat += 1;

			for (offset = 0; offset < repeat; ++offset) {
				data [move + offset] = sprite_colour [colour];
			}

			move += repeat - 1;
		}
	}

	file = file_close (file);

	return (data);
}

static void sprite_export (char * path, int width, int height, unsigned int * data) {
	int file, move;

	file = file_open (path, file_flag_edit | file_flag_truncate | file_flag_create);

	fatal_failure ((width  <= 0) || (width  >= 256), "sprite_export: Invalid sprite width.");
	fatal_failure ((height <= 0) || (height >= 256), "sprite_export: Invalid sprite height.");

	file_write (file, & width,  1);
	file_write (file, & height, 1);

	for (move = 0; move < width * height; ++move) {
		int colour = 0;
		int repeat = 0;

		for (repeat = 1; (move + repeat < width * height) && (data [move] == data [move + repeat]) && (repeat < 256); ++repeat);

		for (colour = 0; (data [move] != sprite_colour [colour]) && (colour < 128); ++colour);

		if (colour == 128) colour = 127;

		if (repeat == 1) {
			file_write (file, & colour, 1);
		} else {
			colour |= 0x80;
			repeat -= 1;
			move   += repeat;

			file_write (file, & colour, 1);
			file_write (file, & repeat, 1);

		}
	}

	file = file_close (file);
}

static void sprite_swap_channels (unsigned int * data, int width, int height) {
	int move;

	for (move = 0; move < width * height; ++move) {
		data [move] = (data [move] & 0xff00ff00) | ((data [move] & 0xff0000) >> 16) | ((data [move] & 0xff) << 16);
	}
}