/*
 * Copyright (C) 2021  P. J. McDermott
 *
 * This file is part of Dodge Balls
 *
 * Dodge Balls 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.
 *
 * Dodge Balls 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 Dodge Balls.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <SDL.h>
#include <SDL_ttf.h>
#include <stdlib.h>
#include "collision.h"
#include "game.h"
#include "main-menu.h"
#include "main.h"
#include "output.h"
#include "util.h"

static int _db_main_menu_quit;

struct _db_main_menu_button {
	SDL_Texture                  *texture_text;
	SDL_Texture                  *texture_over;
	SDL_Rect                      rect;
	struct _db_main_menu_button  *u;
	struct _db_main_menu_button  *d;
	struct _db_main_menu_button  *l;
	struct _db_main_menu_button  *r;
	struct _db_main_menu_button  *p;
	struct _db_main_menu_button  *n;
	void                        (*action)(void *);
	void                         *user_data;
};

static SDL_Texture *
_db_main_menu_text(TTF_Font *font, const char *text, SDL_Color *color,
		int width, SDL_Renderer *renderer, SDL_Rect *rect)
{
	SDL_Surface *surface;
	SDL_Texture *texture;

	surface = TTF_RenderText_Blended_Wrapped(font, text, *color, width);
	if (surface == NULL) {
		db_err("Failed to create surface (%s)", TTF_GetError());
		return NULL;
	}

	texture = SDL_CreateTextureFromSurface(renderer, surface);
	if (texture == NULL) {
		db_err("Failed to create texture (%s)", SDL_GetError());
		return NULL;
	}

	rect->w = surface->w;
	rect->h = surface->h;

	SDL_FreeSurface(surface);

	return texture;
}

static void
_db_main_menu_action_help(void *user_data __attribute__((__unused__)))
{
}

static void
_db_main_menu_action_quit(void *user_data __attribute__((__unused__)))
{
	_db_main_menu_quit = 1;
}

static void
_db_main_menu_action_game(void *user_data)
{
	struct db_game *game;

	game = user_data;

	db_dbg("Loading game \"%s\"", db_game_get_name(game));
}

void
db_main_menu(void)
{
	const char                   *games_dir;
	char                         *font_path;
	SDL_Renderer                 *renderer;
	SDL_Color                     text_color;
	SDL_Color                     over_color;
	SDL_Rect                      dest_rect;
	TTF_Font                     *font;
	SDL_Texture                  *texture_title;
	struct db_game              **games;
	int                           n;
	struct _db_main_menu_button **buttons;
	char                         *name_desc;
	int                           i;
	struct _db_main_menu_button  *active;
	SDL_Event                     event;

	games_dir = db_get_games_dir();
	font_path = db_strcat(db_get_fonts_dir(), "/UbuntuTitling-Bold.ttf");

	renderer = db_get_renderer();

	/* Render background */
	SDL_SetRenderDrawColor(renderer, 0x7F, 0x7F, 0x7F, 0xFF);

	text_color.r = 0x00;
	text_color.g = 0x00;
	text_color.b = 0xFF;
	text_color.a = 0xFF;

	over_color.r = 0xFF;
	over_color.g = 0xFF;
	over_color.b = 0xFF;
	over_color.a = 0xFF;

	/* Render title text */
	font = TTF_OpenFont(font_path, 48);
	if (font == NULL) {
		db_err("Failed to open font (%s)", TTF_GetError());
		free(font_path);
		return;
	}
	texture_title = _db_main_menu_text(font, "Dodge Balls", &text_color, 0,
			renderer, &dest_rect);
	if (texture_title == NULL) {
		goto err;
	}
	dest_rect.x = 16;
	dest_rect.y = 16;

	TTF_CloseFont(font);
	font = TTF_OpenFont(font_path, 16);
	if (font == NULL) {
		db_err("Failed to open font (%s)", TTF_GetError());
		free(font_path);
		return;
	}

	/* Find games */
	games = NULL;
	n = db_games_find(games_dir, &games);
	buttons = calloc(n + 2, sizeof(*buttons));
	if (buttons == NULL) {
		db_err("Failed to allocate memory");
		goto err;
	}

	/* Render help button */
	buttons[0] = malloc(sizeof(**buttons));
	if (buttons[0] == NULL) {
		db_err("Failed to allocate memory");
		goto err;
	}
	buttons[0]->texture_text = _db_main_menu_text(font, "How to Play",
			&text_color, 0, renderer, &buttons[0]->rect);
	if (buttons[0]->texture_text == NULL) {
		goto err;
	}
	buttons[0]->texture_over = _db_main_menu_text(font, "How to Play",
			&over_color, 0, renderer, &buttons[0]->rect);
	if (buttons[0]->texture_over == NULL) {
		goto err;
	}
	buttons[0]->rect.x = 640 - 16 - buttons[0]->rect.w;
	buttons[0]->rect.y = 16;
	buttons[0]->action = &_db_main_menu_action_help;
	buttons[0]->user_data = NULL;

	/* Render quit button */
	buttons[1] = malloc(sizeof(**buttons));
	if (buttons[1] == NULL) {
		db_err("Failed to allocate memory");
		goto err;
	}
	buttons[1]->texture_text = _db_main_menu_text(font, "Quit",
			&text_color, 0, renderer, &buttons[1]->rect);
	if (buttons[1]->texture_text == NULL) {
		goto err;
	}
	buttons[1]->texture_over = _db_main_menu_text(font, "Quit",
			&over_color, 0, renderer, &buttons[1]->rect);
	if (buttons[1]->texture_over == NULL) {
		goto err;
	}
	buttons[1]->rect.x = 640 - 16 - buttons[1]->rect.w;
	buttons[1]->rect.y = 48;
	buttons[1]->action = &_db_main_menu_action_quit;
	buttons[1]->user_data = NULL;

	/* Render game buttons */
	buttons[1]->n = buttons[0];  /* Quit button link (may change below) */
	for (i = 0; i < n; ++i) {
		buttons[i + 2] = malloc(sizeof(**buttons));
		if (buttons[i + 2] == NULL) {
			db_err("Failed to allocate memory");
			goto err;
		}
		name_desc = malloc((strlen(db_game_get_name(games[i])) +
					strlen(db_game_get_desc(games[i])) + 2)
					* sizeof(*name_desc));
		if (name_desc == NULL) {
			db_err("Failed to allocate memory");
			goto err;
		}
		sprintf(name_desc, "%s\n%s", db_game_get_name(games[i]),
				db_game_get_desc(games[i]));
		buttons[i + 2]->rect.x = 16;
		buttons[i + 2]->rect.y = 80 + 48 * i + 2;
		buttons[i + 2]->texture_text = _db_main_menu_text(font,
				name_desc, &text_color, 608, renderer,
				&buttons[i + 2]->rect);
		if (buttons[i + 2]->texture_text == NULL) {
			free(name_desc);
			goto err;
		}
		buttons[i + 2]->texture_over = _db_main_menu_text(font,
				name_desc, &over_color, 608, renderer,
				&buttons[i + 2]->rect);
		free(name_desc);
		if (buttons[i + 2]->texture_over == NULL) {
			goto err;
		}
		if (i > 0) {
			buttons[i + 2]->u = buttons[i + 1];
			buttons[i + 1]->d = buttons[i + 2];
		}
		buttons[i + 2]->l = NULL;
		buttons[i + 2]->r = buttons[0];
		buttons[i + 2]->p = buttons[i + 1];
		buttons[i + 1]->n = buttons[i + 2];
		buttons[i + 2]->action = &_db_main_menu_action_game;
		buttons[i + 2]->user_data = games[i];
	}
	if (n > 0) {
		buttons[2]->u = NULL;
		buttons[n + 1]->d = NULL;
		buttons[i + 1]->n = buttons[0];
	}

	/* Help button links */
	buttons[0]->u = NULL;
	buttons[0]->d = buttons[1];
	if (n > 0) {
		buttons[0]->l = buttons[2];
	} else {
		buttons[0]->l = NULL;
	}
	buttons[0]->r = NULL;
	buttons[0]->p = buttons[1 + n];
	buttons[0]->n = buttons[1];

	/* Quit button links */
	buttons[1]->u = buttons[0];
	buttons[1]->d = NULL;
	if (n > 0) {
		buttons[1]->l = buttons[2];
	} else {
		buttons[1]->l = NULL;
	}
	buttons[1]->r = NULL;
	buttons[1]->p = buttons[0];

	if (n > 0) {
		active = buttons[2];
	} else {
		active = buttons[1];
	}

	_db_main_menu_quit = 0;
	while (SDL_WaitEvent(&event)) {
		switch (event.type) {
			case SDL_QUIT:
				_db_main_menu_quit = 1;
				break;
			case SDL_KEYDOWN:
				switch (event.key.keysym.sym) {
					case SDLK_UP:
						if (active->u != NULL) {
							active = active->u;
						}
						break;
					case SDLK_DOWN:
						if (active->d != NULL) {
							active = active->d;
						}
						break;
					case SDLK_LEFT:
						if (active->l != NULL) {
							active = active->l;
						}
						break;
					case SDLK_RIGHT:
						if (active->r != NULL) {
							active = active->r;
						}
						break;
					case SDLK_TAB:
						if (event.key.keysym.mod &
								KMOD_SHIFT) {
							if (active->p != NULL) {
								active =
								      active->p;
							}
						} else {
							if (active->n != NULL) {
								active =
								      active->n;
							}
						}
						break;
					case SDLK_RETURN:
						active->action(
							     active->user_data);
						break;
					default:
						break;
				}
				break;
			case SDL_MOUSEMOTION:
				if (event.motion.state != 0) {
					break;
				}
				for (i = 0; i < n + 2; ++i) {
					if (db_pt_in_rect(event.motion.x,
							     event.motion.y,
							     &buttons[i]->rect))
					{
						active = buttons[i];
						break;
					}
				}
				break;
			case SDL_MOUSEBUTTONUP:
				if (event.button.button != SDL_BUTTON_LEFT) {
					break;
				}
				if (db_pt_in_rect(event.button.x,
							event.button.y,
							&active->rect)) {
					active->action(active->user_data);
				}
				break;
			default:
				break;
		}
		SDL_RenderClear(renderer);
		SDL_RenderCopy(renderer, texture_title, NULL, &dest_rect);
		for (i = 0; i < n + 2; ++i) {
			if (buttons[i] == active) {
				SDL_RenderCopy(renderer,
						buttons[i]->texture_over, NULL,
						&buttons[i]->rect);
			} else {
				SDL_RenderCopy(renderer,
						buttons[i]->texture_text, NULL,
						&buttons[i]->rect);
			}
		}
		SDL_RenderPresent(renderer);
		if (_db_main_menu_quit == 1) {
			break;
		}
	}

 err:
	free(font_path);
	TTF_CloseFont(font);
	SDL_DestroyTexture(texture_title);
}