/*
 * Copyright (C) 2003, Hyriand <hyriand@thegraveyard.org>
 * Copyright (C) 2014, Johannes Löthberg <johannes@kyriasis.com>
 *
 * This program is free software; 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#define _GNU_SOURCE
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <Imlib2.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <errno.h>
#include <argp.h>

#include "yawa.h"
#include "config.h"


/* Order of parameters: KEY, ARG, STATE. */
static error_t
parse_opt (int key, char *arg, struct argp_state *state)
{
	struct arguments *arguments = state->input;
	char *endptr;
	long val;
	errno = 0;

	switch (key) {
		case 'a':
			arguments->add = true;
			strncpy(arguments->add_color[num_add_colors], arg, sizeof(arguments->add_color[0]));
			num_add_colors += 1;
			break;
		case 'g':
			arguments->gradient = true;
			val = strtol(arg, &endptr, 10);
			arguments->angle = (int)val;

			if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
					|| (errno != 0 && val == 0)) {
				perror("strtol");
				exit(-2);
			}

			if (endptr == arg) {
				fprintf(stderr, "No digits were found\n");
				exit(-2);
			}
			break;
		case 'c':
			arguments->clear = true;
			break;
		case 's':
			arguments->solid = true;
			arguments->color = arg;
			break;
		case 'C':
			arguments->center = true;
			arguments->image = arg;
			break;
		case 't':
			arguments->tile = true;
			arguments->image = arg;
			break;
		case 'f':
			arguments->full = true;
			arguments->image = arg;
			break;
		case 'F':
			arguments->fill = true;
			arguments->image = arg;
			break;
		case 'T':
			arguments->tint = true;
			arguments->color = arg;
			break;
		case 'A':
			arguments->alpha = true;
			val = strtol(arg, &endptr, 10);
			arguments->alpha_amount = (int)val;

			if ((errno == ERANGE && (val == LONG_MAX || val == LONG_MIN))
					|| (errno != 0 && val == 0)) {
				perror("strtol");
				exit(-2);
			}

			if (endptr == arg) {
				fprintf(stderr, "No digits were found\n");
				exit(-2);
			}
			break;
		default:
			return ARGP_ERR_UNKNOWN;
	}
	return 0;
}

/* The ARGP structure itself. */
static struct argp argp = {options, parse_opt, "", doc, NULL, NULL, 0};

// Globals:
static Display *display;
static int screen;

// Adapted from fluxbox' bsetroot
int
setRootAtoms (Pixmap pixmap)
{
	Atom atom_root, atom_eroot, type;
	unsigned char *data_root, *data_eroot;
	int format;
	unsigned long length, after;

	atom_root = XInternAtom (display, "_XROOTMAP_ID", True);
	atom_eroot = XInternAtom (display, "ESETROOT_PMAP_ID", True);

	// doing this to clean up after old background
	if (atom_root != None && atom_eroot != None)
	{
		XGetWindowProperty (display, RootWindow (display, screen),
		                    atom_root, 0L, 1L, False, AnyPropertyType,
		                    &type, &format, &length, &after, &data_root);
		if (type == XA_PIXMAP)
		{
			XGetWindowProperty (display, RootWindow (display, screen),
			                    atom_eroot, 0L, 1L, False, AnyPropertyType,
			                    &type, &format, &length, &after, &data_eroot);
			if (data_root && data_eroot && type == XA_PIXMAP &&
			    *(data_root) == *(data_eroot))
			{
				XKillClient (display, *(data_root));
			}
		}
	}

	atom_root = XInternAtom (display, "_XROOTPMAP_ID", False);
	atom_eroot = XInternAtom (display, "ESETROOT_PMAP_ID", False);

	if (atom_root == None || atom_eroot == None)
		return 0;

	// setting new background atoms
	XChangeProperty (display, RootWindow (display, screen),
	                 atom_root, XA_PIXMAP, 32, PropModeReplace,
	                 (unsigned char *) &pixmap, 1);
	XChangeProperty (display, RootWindow (display, screen), atom_eroot,
	                 XA_PIXMAP, 32, PropModeReplace, (unsigned char *) &pixmap,
	                 1);

	return 1;
}

int
getHex (char c)
{
	switch (c)
	{
		case '0':
		case '1':
		case '2':
		case '3':
		case '4':
		case '5':
		case '6':
		case '7':
		case '8':
		case '9':
			return c - '0';
		case 'A':
		case 'B':
		case 'C':
		case 'D':
		case 'E':
		case 'F':
			return c - 'A' + 10;
		case 'a':
		case 'b':
		case 'c':
		case 'd':
		case 'e':
		case 'f':
			return c - 'a' + 10;
		default:
			return 0;
	}
}

int
parse_color (char *arg, PColor c, int a)
{
	if (arg[0] != '#')
		return 0;

	if ((strlen (arg) != 7) && (strlen (arg) != 9))
		return 0;

	c->r = getHex (arg[1]) * 16 + getHex (arg[2]);
	c->g = getHex (arg[3]) * 16 + getHex (arg[4]);
	c->b = getHex (arg[5]) * 16 + getHex (arg[6]);
	c->a = a;
	if (strlen (arg) == 9)
		c->a = getHex (arg[7]) * 16 + getHex (arg[8]);

	return 1;
}

int
load_image (ImageMode mode, const char *arg, int rootW, int rootH, int alpha,
            Imlib_Image rootimg)
{
	int imgW, imgH, o;
	Imlib_Image buffer = imlib_load_image (arg);

	if (!buffer)
		return 0;

	imlib_context_set_image (buffer);
	imgW = imlib_image_get_width (), imgH = imlib_image_get_height ();

	if (alpha < 255)
	{
		// Create alpha-override mask
		imlib_image_set_has_alpha (1);
		Imlib_Color_Modifier modifier = imlib_create_color_modifier ();
		imlib_context_set_color_modifier (modifier);

		DATA8 red[256], green[256], blue[256], alph[256];
		imlib_get_color_modifier_tables (red, green, blue, alph);
		for (o = 0; o < 256; o++)
			alph[o] = (DATA8) alpha;
		imlib_set_color_modifier_tables (red, green, blue, alph);

		imlib_apply_color_modifier ();
		imlib_free_color_modifier ();
	}

	imlib_context_set_image (rootimg);
	if (mode == Fill)
	{
		imlib_blend_image_onto_image (buffer, 0, 0, 0, imgW, imgH,
		                              0, 0, rootW, rootH);
	}
	else if (mode == Full)
	{
		double aspect = ((double) rootW) / imgW;
		int top, left;
		if ((int) (imgH * aspect) > rootH)
			aspect = (double) rootH / (double) imgH;
		top = (rootH - (int) (imgH * aspect)) / 2;
		left = (rootW - (int) (imgW * aspect)) / 2;
		imlib_blend_image_onto_image (buffer, 0, 0, 0, imgW, imgH,
		                              left, top, (int) (imgW * aspect),
		                              (int) (imgH * aspect));
	}
	else
	{
		int left = (rootW - imgW) / 2, top = (rootH - imgH) / 2;

		if (mode == Tile)
		{
			int x, y;
			for (; left > 0; left -= imgW);
			for (; top > 0; top -= imgH);

			for (x = left; x < rootW; x += imgW)
				for (y = top; y < rootH; y += imgH)
					imlib_blend_image_onto_image (buffer, 0, 0, 0, imgW, imgH,
					                              x, y, imgW, imgH);
		}
		else
		{
			imlib_blend_image_onto_image (buffer, 0, 0, 0, imgW, imgH,
			                              left, top, imgW, imgH);
		}
	}

	imlib_context_set_image (buffer);
	imlib_free_image ();

	imlib_context_set_image (rootimg);

	return 1;
}

int
main (int argc, char **argv)
{
	struct arguments arguments = {
	    "", "", 0, 0, false,
	    false, false, false, false, false, false, false, false, false,
	    false, false, false, false, false, false, false, false, false,
	    {{0}} // add_color array
	};

	/* Where the magic happens */
	argp_parse (&argp, argc, argv, 0, 0, &arguments);

	Visual *vis;
	Colormap cm;
	Display *_display;
	Imlib_Context *context;
	Imlib_Image image;
	int width, height, depth, alpha;
	int i = 0;
	Pixmap pixmap;
	Imlib_Color_Modifier modifier = NULL;
	_display = XOpenDisplay (NULL);

	for (screen = 0; screen < ScreenCount (_display); screen++)
	{
		display = XOpenDisplay (NULL);

		context = imlib_context_new ();
		imlib_context_push (context);

		imlib_context_set_display (display);
		vis = DefaultVisual (display, screen);
		cm = DefaultColormap (display, screen);
		width = DisplayWidth (display, screen);
		height = DisplayHeight (display, screen);
		depth = DefaultDepth (display, screen);

		pixmap =
			XCreatePixmap (display, RootWindow (display, screen), (unsigned int) width, (unsigned int) height,
			               (unsigned int) depth);

		imlib_context_set_visual (vis);
		imlib_context_set_colormap (cm);
		imlib_context_set_drawable (pixmap);
		imlib_context_set_color_range (imlib_create_color_range ());

		image = imlib_create_image (width, height);
		imlib_context_set_image (image);

		imlib_context_set_color (0, 0, 0, 255);
		imlib_image_fill_rectangle (0, 0, width, height);

		imlib_context_set_dither (1);
		imlib_context_set_blend (1);

		alpha = 255;

			if (modifier != NULL)
			{
				imlib_apply_color_modifier ();
				imlib_free_color_modifier ();
			}
			modifier = imlib_create_color_modifier ();
			imlib_context_set_color_modifier (modifier);

			if (arguments.alpha)
			{
				alpha = arguments.alpha;
			}
			if (arguments.solid)
			{
				Color c;
				if (parse_color (arguments.color, &c, alpha) == 0)
				{
					fprintf (stderr, "Bad color (%s)\n", arguments.color);
					continue;
				}
				imlib_context_set_color (c.r, c.g, c.b, c.a);
				imlib_image_fill_rectangle (0, 0, width, height);
			}
			if (arguments.clear)
			{
				imlib_free_color_range ();
				imlib_context_set_color_range (imlib_create_color_range ());
			}
			// TODO: Add back -add and -addd
			if (arguments.add)
			{
				for (i = 0; i < num_add_colors; i++)
				{
					Color c;
					if (parse_color (arguments.add_color[i], &c, alpha) == 0)
					{
						fprintf (stderr, "Bad color (%s)\n", arguments.add_color[i]);
						continue;
					}
					imlib_context_set_color (c.r, c.g, c.b, c.a);
					imlib_add_color_to_color_range (1);
				}
			}
			if (arguments.gradient)
			{
				imlib_image_fill_color_range_rectangle (0, 0, width, height,
				                                        arguments.angle);
			}
			if (arguments.fill)
			{
				if (load_image (Fill, arguments.image, width, height, alpha, image) ==
				                0)
				{
					fprintf (stderr, "Bad image (%s)\n", arguments.image);
					continue;
				}
			}
			if (arguments.full)
			{
				if (load_image (Full, arguments.image, width, height, alpha, image) ==
				                0)
				{
					fprintf (stderr, "Bad image (%s)\n", arguments.image);
					continue;
				}
			}
			if (arguments.tile)
			{
				if (load_image (Tile, arguments.image, width, height, alpha, image) ==
				                0)
				{
					fprintf (stderr, "Bad image (%s)\n", arguments.image);
					continue;
				}
			}
			if (arguments.center)
			{
				if (load_image (Center, arguments.image, width, height, alpha, image) ==
				                0)
				{
					fprintf (stderr, "Bad image (%s)\n", arguments.image);
					continue;
				}
			}
			if (arguments.tint)
			{
				Color c;
				DATA8 r[256], g[256], b[256], a[256];
				int j;

				if (parse_color (arguments.color, &c, 255) == 0)
				{
					fprintf (stderr, "Bad color\n");
					continue;
				}

				imlib_get_color_modifier_tables (r, g, b, a);

				for (j = 0; j < 256; j++)
				{
					r[j] = (DATA8) (((double) r[j] / 255.0) * (double) c.r);
					g[j] = (DATA8) (((double) g[j] / 255.0) * (double) c.g);
					b[j] = (DATA8) (((double) b[j] / 255.0) * (double) c.b);
				}

				imlib_set_color_modifier_tables (r, g, b, a);
			}
			if (arguments.blur)
			{
				int intval;
				if (sscanf (argv[i], "%i", &intval) == 0)
				{
					fprintf (stderr, "Bad value (%s)\n", argv[i]);
					continue;
				}
				imlib_image_blur (intval);
			}
			if (arguments.sharpen)
			{
				int intval;
				if ((++i) >= argc)
				{
					fprintf (stderr, "Missing value\n");
					continue;
				}
				if (sscanf (argv[i], "%i", &intval) == 0)
				{
					fprintf (stderr, "Bad value (%s)\n", argv[i]);
					continue;
				}
				imlib_image_sharpen (intval);
			}
			if (arguments.contrast)
			{
				double dblval;
				if ((++i) >= argc)
				{
					fprintf (stderr, "Missing value\n");
					continue;
				}
				if (sscanf (argv[i], "%lf", &dblval) == 0)
				{
					fprintf (stderr, "Bad value (%s)\n", argv[i]);
					continue;
				}
				imlib_modify_color_modifier_contrast (dblval);
			}
			if (arguments.brightness)
			{
				double dblval;
				if ((++i) >= argc)
				{
					fprintf (stderr, "Missing value\n");
					continue;
				}
				if (sscanf (argv[i], "%lf", &dblval) == 0)
				{
					fprintf (stderr, "Bad value (%s)\n", argv[i]);
					continue;
				}
				imlib_modify_color_modifier_brightness (dblval);
			}
			if (arguments.gamma)
			{
				double dblval;
				if ((++i) >= argc)
				{
					fprintf (stderr, "Missing value\n");
					continue;
				}
				if (sscanf (argv[i], "%lf", &dblval) == 0)
				{
					fprintf (stderr, "Bad value (%s)\n", argv[i]);
					continue;
				}
				imlib_modify_color_modifier_gamma (dblval);
			}
			if (arguments.flipv)
			{
				imlib_image_flip_vertical ();
			}
			if (arguments.fliph)
			{
				imlib_image_flip_horizontal ();
			}
			if (arguments.flipd)
			{
				imlib_image_flip_diagonal ();
			}
			if (arguments.write)
			{
				imlib_save_image (argv[i]);
			}

		if (modifier != NULL)
		{
			imlib_context_set_color_modifier (modifier);
			imlib_apply_color_modifier ();
			imlib_free_color_modifier ();
			modifier = NULL;
		}
		imlib_render_image_on_drawable (0, 0);
		imlib_free_image ();
		imlib_free_color_range ();

		if (setRootAtoms (pixmap) == 0)
			fprintf (stderr, "Couldn't create atoms...\n");

		XKillClient (display, AllTemporary);
		XSetCloseDownMode (display, RetainTemporary);

		XSetWindowBackgroundPixmap (display, RootWindow (display, screen),
		                            pixmap);
		XClearWindow (display, RootWindow (display, screen));

		XFlush (display);
		XSync (display, False);

		imlib_context_pop ();
		imlib_context_free (context);
	}

	return 0;
}