/*
 * Copyright (C) 2021  P. J. McDermott
 *
 * This file is part of Maze Fight
 *
 * Maze Fight 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 3 of the License, or
 * (at your option) any later version.
 *
 * Maze Fight 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 Maze Fight.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <SDL.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "../tk.h"
#include "widget.h"

struct _mftk_radio_state {
	struct mftk_radio *r;
	int                state;
};

struct mftk_radio {
	struct mftk_widget         parent;
	struct mftk_widget       **children;
	struct mftk_widget        *grid;
	struct _mftk_radio_state  *states;
	int                        state;
	int                        options;
	int                      (*action)(void *, int);
	int                      (*submit)(void *);
	void                      *user_data;
};

static int
_mftk_radio_state_change(void *user_data, int state)
{
	struct _mftk_radio_state *rs = (struct _mftk_radio_state *) user_data;

	if (state == SDL_FALSE) {
		/* Radio buttons can't be deselected */
		mftk_check_set_state(rs->r->children[rs->r->state], SDL_TRUE);
		return 0;
	} else {
		/* Deselect previous check button */
		mftk_check_set_state(rs->r->children[rs->r->state], SDL_FALSE);
		/* Set and announce new state */
		rs->r->state = rs->state;
		if (rs->r->action == NULL) {
			return 0;
		}
		return rs->r->action(rs->r->user_data, rs->r->state);
	}
}

static void
_mftk_radio_layout(struct mftk_widget *w)
{
	struct mftk_radio *r = (struct mftk_radio *) w;

	mftk_widget_layout(r->grid);
	w->w = r->grid->w;
	w->h = r->grid->h;
}

static void
_mftk_radio_focus(struct mftk_widget *w __attribute__((__unused__)))
{
	/* Nothing to do */
}

static void
_mftk_radio_defocus(struct mftk_widget *w __attribute__((__unused__)))
{
	/* Nothing to do */
}

static int
_mftk_radio_key_event(struct mftk_widget *w, SDL_Event *e)
{
	struct mftk_radio *r = (struct mftk_radio *) w;

	switch (e->type) {
		case SDL_KEYDOWN:
			switch (e->key.keysym.sym) {
				case SDLK_UP:
					mftk_check_set_state(r->children[
							r->state], SDL_FALSE);
					--r->state;
					if (r->state < 0) {
						r->state = r->options - 1;
					}
					mftk_check_set_state(r->children[
							r->state], SDL_TRUE);
					if (r->action == NULL) {
						return 0;
					}
					return r->action(r->user_data,r->state);
				case SDLK_DOWN:
					mftk_check_set_state(r->children[
							r->state], SDL_FALSE);
					++r->state;
					if (r->state >= r->options) {
						r->state = 0;
					}
					mftk_check_set_state(r->children[
							r->state], SDL_TRUE);
					if (r->action == NULL) {
						return 0;
					}
					return r->action(r->user_data,r->state);
				case SDLK_RETURN:
				case SDLK_KP_ENTER:
					return r->submit(r->user_data);
				default:
					break;
			}
		default:
			break;
	}

	return 0;
}

static int
_mftk_radio_mouse_event(struct mftk_widget *w, SDL_Event *e, int x, int y)
{
	struct mftk_radio *r = (struct mftk_radio *) w;

	switch (e->type) {
		case SDL_MOUSEBUTTONUP:
			if (e->button.button == SDL_BUTTON_LEFT) {
				mftk_window_focus(w->window, w);
				return mftk_widget_mouse_event(r->grid, e,
						x, y);
			}
			break;
		default:
			break;
	}

	return 0;
}

static int
_mftk_radio_render(struct mftk_widget *w, SDL_Renderer *renderer, int x, int y)
{
	struct mftk_radio *r = (struct mftk_radio *) w;

	return mftk_widget_render(r->grid, renderer, x, y);
}

static void
_mftk_radio_destroy(struct mftk_widget *w)
{
	struct mftk_radio *r = (struct mftk_radio *) w;

	mftk_widget_destroy(&r->grid);
	free(r->states);
}

struct mftk_widget *
mftk_radio_new(int butn_width, int butn_padding, int label_padding,
		int item_padding, TTF_Font *font, int (*action)(void *, int),
		int (*submit)(void *), void *user_data, SDL_Renderer *renderer,
		int state, int options, ...)
{
	struct mftk_widget *w;
	struct mftk_radio  *r;
	va_list             ap;
	int                 i;

	mftk_widget_init_focusable(w, r, radio);

	r->children = calloc(options, sizeof(*r->children));
	if (r->children == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create widget: %s",
				strerror(errno));
		free(r);
		return NULL;
	}
	r->states = calloc(options, sizeof(*r->states));
	if (r->states == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create widget: %s",
				strerror(errno));
		free(r->children);
		free(r);
		return NULL;
	}

	va_start(ap, options);
	for (i = 0; i < options; ++i) {
		r->children[i] = mftk_check_new(butn_width, butn_padding,
				(i == state), label_padding, font,
				va_arg(ap, const char *),
				&_mftk_radio_state_change, submit,
				&r->states[i], renderer);
		if (r->children[i] == NULL) {
			for (; i >= 0; --i) {
				mftk_widget_destroy(&r->children[i]);
			}
			free(r->children);
			free(r->states);
			free(r);
			va_end(ap);
			return NULL;
		}
		mftk_check_set_shape(r->children[i], MFTK_CHECK_SHAPE_CIR);
		mftk_check_set_steals_focus(r->children[i], SDL_FALSE);
		r->states[i].r     = r;
		r->states[i].state = i;
	}
	va_end(ap);

	r->grid = mftk_grid_new_a(options, 1, item_padding, 0, r->children,
			NULL);
	if (r->grid == NULL) {
		for (i = 0; i < options; ++i) {
			mftk_widget_destroy(&r->children[i]);
		}
		free(r->children);
		free(r->states);
		free(r);
	}

	r->state     = state;
	r->options   = options;
	r->action    = action;
	r->submit    = submit;
	r->user_data = user_data;

	return w;
}