#include <xolatile/xyntax.h>

#include <png.h>

#include "language/ada.h"
#include "language/assembly.h"
#include "language/c.h"
#include "language/c++.h"
#include "language/eaxhla.h"
#include "language/flat.h"
#include "language/fortran.h"
#include "language/xofya.h"

static struct {
	void (* highlighter) (void);
	char  * option_short;
	char  * option_long;
} const language [] = {
	{ highlight_ada,      "-A", "--ada"      },
	{ highlight_assembly, "-S", "--assembly" },
	{ highlight_c,        "-C", "--c"        },
	{ highlight_cpp,      "-P", "--c++"      },
	{ highlight_eaxhla,   "-E", "--eaxhla"   },
	{ highlight_flat,     "-T", "--flat"     },
	{ highlight_fortran,  "-F", "--fortran"  },
	{ highlight_xofya,    "-X", "--xofya"    }
};

static int   background    = 0xff181818;
static int   tab_width     = 8;
static int   render_border = 10;
static int * render_image  = null;
static int   render_width  = 0;
static int   render_height = 0;
static int * font_source   = null;
static int   font_width    = 0;
static int   font_height   = 0;
static int   line_number   = 0;
static int   line_digits   = 0;

static void import_png_as_glyphmap (const char * path) {
	png_image image = { 0 };

	image.version = PNG_IMAGE_VERSION;

	png_image_begin_read_from_file (& image, path);

	image.format = PNG_FORMAT_RGBA;

	font_width  = image.width  / 16;
	font_height = image.height /  6;

	font_source = allocate (image.width * image.height * (int) sizeof (* font_source));

	png_image_finish_read (& image, null, font_source, 0, null);

	png_image_free (& image);
}

static void export_render_as_png (const char * path) {
	png_image image = { 0 };

	image.version = PNG_IMAGE_VERSION;
	image.format  = PNG_FORMAT_RGBA;
	image.width   = (unsigned int) render_width;
	image.height  = (unsigned int) render_height;

	png_image_write_to_file (& image, path, 0, render_image, 0, null);

	png_image_free (& image);
}

static int fetch_width (const char * data) {
	int image_width = 0;
	int count       = 0;

	do {
		if (* data == '\t') {
			count += tab_width;
		} else if (* data == '\n') {
			image_width = (++count > image_width) ? count : image_width;
			count = 0;
		} else {
			++count;
		}
	} while (* (++data) != '\0');

	return (image_width - 1);
}

static int fetch_height (const char * data) {
	int image_height = 0;
	int count        = 0;

	do {
		if (* data == '\n') {
			++image_height;
		}
	} while (* (++data) != '\0');

	count = image_height + 1;

	do {
		++line_digits;

		count /= 10;
	} while (count > 0);

	return (image_height + 1);
}

static int interpolate_pixel (int pixel, int colour) {
	int r, g, b, a;

	a = (pixel >> 24) & 0xff;

	if (a == 0x00) {
		return (background);
	} else if (a == 0xff) {
		return (colour);
	} else {
		r = (((background >>  0) & 0xff) * (0xff - a) + ((colour >>  0) & 0xff) * a) / 0xff;
		g = (((background >>  8) & 0xff) * (0xff - a) + ((colour >>  8) & 0xff) * a) / 0xff;
		b = (((background >> 16) & 0xff) * (0xff - a) + ((colour >> 16) & 0xff) * a) / 0xff;

		return ((r << 0) | (g << 8) | (b << 16) | 0xff000000);
	}
}

static void render_character (char character, int * x, int * y, int colour) {
	int offset_x = 0;
	int offset_y = 0;
	int offset_u = (character - ' ') % 16;
	int offset_v = (character - ' ') / 16;

	for (offset_y = 0; offset_y < font_height; ++offset_y) {
		for (offset_x = 0; offset_x < font_width; ++offset_x) {
			int destination = (* y + offset_y) * render_width + (* x + offset_x);
			int source      = (offset_v * font_height + offset_y) * font_width * 16 + (offset_u * font_width + offset_x);

			render_image [destination] = interpolate_pixel (font_source [source], colour);
		}
	}

	* x += font_width;
}

static void render_string (char * string, int length, int * x, int * y, int colour) {
	int offset;

	for (offset = 0; offset < length; ++offset) {
		if (string [offset] == '\t') {
			* x += font_width * tab_width;
		} else if (string [offset] == '\n') {
			* y += font_height;
			* x  = render_border;

			render_string (format_to_string (++line_number, false, 10, line_digits, ' '), line_digits, x, y, (int) 0xffeeeeee);

			* x += font_width;
		} else {
			render_character (string [offset], x, y, colour);
		}
	}
}

int main (int argc, char * * argv) {
	int    offset = 0;
	int    select = 0;
	int    length = 0;
	int    x      = render_border;
	int    y      = render_border;
	char * buffer = null;

	if (argc != 1) {
		if (string_compare (argv [1], "-v") || string_compare (argv [1], "--version")) {
			echo ("xarbon: Source code renderer (version 144)\n");
			exit (log_success);
		} else if (string_compare (argv [1], "-l") || string_compare (argv [1], "--license")) {
			echo ("xarbon: Source code renderer (GNU/GPLv3)\n");
			exit (log_success);
		} else if (string_compare (argv [1], "-a") || string_compare (argv [1], "--author")) {
			echo ("xarbon: Source code renderer (Ognjen 'xolatile' Milan Robovic)\n");
			exit (log_success);
		} else if (string_compare (argv [1], "-h") || string_compare (argv [1], "--help")) {
			echo ("xarbon: Source code renderer:\n");
			echo ("Example usage:\n");
			echo ("\t$ cat file.ext | xarbon [flag] -- You need to pass language flag in this case.\n");
			echo ("\t$ xarbon [flag] < file.ext     -- You need to pass language flag in this case.\n");
			echo ("\t$ xarbon file.ext              -- Language is automatically detected in this case.\n");
			echo ("Supported languages:\n");
			echo ("\t -C --c        -- C syntax\n");
			echo ("\t -A --ada      -- Ada syntax\n");
			echo ("\t -P --cpp      -- C++ syntax \n");
			echo ("\t -S --assembly -- General assembly syntax\n");
			echo ("\t -T --flat     -- Flat assembly syntax\n");
			echo ("\t -F --fortran  -- Fortran syntax\n");
			echo ("\t -X --xofya    -- Xofya syntax\n");
			exit (log_success);
		} else {
			int index;

			for (index = 0; index < (int) (sizeof (language) / sizeof (* language)); ++index) {
				if ((string_compare (argv [1], language [index].option_short) == true)
				||  (string_compare (argv [1], language [index].option_long)  == true)) {
					language [index].highlighter ();
					break;
				}
			}

			if (syntax_active == false) {
				select = file_type   (argv [1]);
				buffer = file_import (argv [1]);
			}
		}
	}

	if (buffer == null) {
		buffer = record ();
	}

	if (syntax_active == false) {
		if ((select == file_type_c_source) || (select == file_type_c_header)) {
			highlight_c ();
		} else if ((select == file_type_ada_body) || (select == file_type_ada_specification)) {
			highlight_ada ();
		} else if ((select == file_type_cpp_source) || (select == file_type_cpp_header)) {
			highlight_cpp ();
		} else if (select == file_type_common_assembly) {
			highlight_assembly ();
		} else if (select == file_type_flat_assembly) {
			highlight_flat ();
		} else if (select == file_type_fortran_90) {
			highlight_fortran ();
		/*} else if (select == file_type_xofya) {
			highlight_xofya ();*/
		}
	}

	import_png_as_glyphmap ("/usr/local/bin/xarbon_font.png");

	render_width  = fetch_width  (buffer) * font_width  + 2 * render_border;
	render_height = fetch_height (buffer) * font_height + 2 * render_border;

	render_width += (line_digits + 1) * font_width;

	render_image = allocate (render_width * render_height * (int) sizeof (* render_image));

	for (offset = 0; offset < render_width * render_height; ++offset) {
		render_image [offset] = background;
	}

	render_string (format_to_string (++line_number, false, 10, line_digits, ' '), line_digits, & x, & y, (int) 0xffeeeeee);

	x += font_width;

	for (offset = 0; buffer [offset] != '\0'; offset += length) {
		select = syntax_select (& buffer [offset], & length);

		render_string (& buffer [offset], length, & x, & y, (select >= syntax_count) ? (int) background : syntax_colour [select]);
	}

	export_render_as_png ("./xarbon.png");

	render_image = deallocate (render_image);
	font_source  = deallocate (font_source);
	buffer       = deallocate (buffer);

	return (log_success);
}