/*
 * 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 <SDL_ttf.h>
#include "../tk.h"
#include "style.h"
#include "widget.h"

struct mftk_label {
	struct mftk_widget  parent;
	SDL_Texture        *texture;
	int                 y;
	int                 h;
};

static SDL_Color _mftk_label_color = {
	.r = MFTK_COLOR_FORE_R, .g = MFTK_COLOR_FORE_G,
	.b = MFTK_COLOR_FORE_B, .a = MFTK_COLOR_FORE_A
};

static void
_mftk_label_layout(struct mftk_widget *w __attribute__((__unused__)))
{
	/* Size set in constructor */
}

static int
_mftk_label_mouse_event(struct mftk_widget *w __attribute__((__unused__)),
		SDL_Event *e __attribute__((__unused__)),
		int x __attribute__((__unused__)),
		int y __attribute__((__unused__)))
{
	/* No events */
	return 0;
}

static int
_mftk_label_render(struct mftk_widget *w, SDL_Renderer *renderer, int x, int y)
{
	struct mftk_label *l = (struct mftk_label *) w;
	SDL_Rect           rect;

	rect.x =        x;
	rect.y = l->y + y;
	rect.w = w->w;
	rect.h = l->h;

	if (SDL_RenderCopy(renderer, l->texture, NULL, &rect) < 0) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't render widget: %s",
				SDL_GetError());
		return -1;
	}

	return 0;
}

static void
_mftk_label_destroy(struct mftk_widget *w)
{
	struct mftk_label *l = (struct mftk_label *) w;

	SDL_DestroyTexture(l->texture);
}

struct mftk_widget *
mftk_label_new(TTF_Font *font, const char *text, SDL_Renderer *renderer)
{
	struct mftk_widget *w;
	struct mftk_label  *l;
	SDL_Surface        *surface;
	int                 line_skip;
	int                 ascent;
	int                 max_y;
	const char         *c;
	int                 glyph_max_y;

	mftk_widget_init(w, l, label);

	surface = TTF_RenderUTF8_Blended(font, text, _mftk_label_color);
	if (surface == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create surface: %s",
				TTF_GetError());
		free(l);
		return NULL;
	}

	l->texture = SDL_CreateTextureFromSurface(renderer, surface);
	if (l->texture == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create texture: %s",
				SDL_GetError());
		SDL_FreeSurface(surface);
		free(l);
		return NULL;
	}

	line_skip = TTF_FontLineSkip(font);
	ascent    = TTF_FontAscent  (font);
	max_y = 0;
	for (c = text; *c != '\0'; ++c) {
		if (TTF_GlyphMetrics(font, *c, NULL, NULL, NULL, &glyph_max_y,
					NULL) < 0) {
			SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
					"Couldn't get glyph metrics: %s",
					TTF_GetError());
			continue;
		}
		if (glyph_max_y > max_y) {
			max_y = glyph_max_y;
		}
	}
	w->w = surface->w;
	w->h = line_skip;
	l->y = (line_skip - ascent) / 2 + (ascent - max_y);
	l->h = surface->h;

	SDL_FreeSurface(surface);

	return w;
}