/*
 * BreakHack - A dungeone crawler RPG
 * Copyright (C) 2018  Linus Probert <linus.probert@gmail.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 3 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/>.
 */

#include <stdlib.h>
#include <assert.h>

#include "monster.h"
#include "util.h"
#include "player.h"
#include "monster.h"
#include "random.h"
#include "gui.h"
#include "item.h"
#include "item_builder.h"
#include "map.h"
#include "particle_engine.h"

static void
monster_load_texts(Monster *m, SDL_Renderer *renderer)
{
	ActionText *t = actiontext_create();
	actiontext_load_font(t, "assets/GUI/SDS_6x6.ttf", 14);
	t->color = (SDL_Color) { 255, 100, 0, 255 };
	actiontext_set_text(t, "HIT", renderer);
	t->pos = m->sprite->pos;
	m->hitText = t;

	t = actiontext_create();
	actiontext_load_font(t, "assets/GUI/SDS_6x6.ttf", 14);
	t->color = (SDL_Color) { 255, 255, 0, 255 };
	actiontext_set_text(t, "MISS", renderer);
	t->pos = m->sprite->pos;
	m->missText = t;
}

Monster*
monster_create(SDL_Renderer *renderer)
{
	Monster *m = ec_malloc(sizeof(Monster));
	m->sprite = sprite_create();
	m->sprite->clip = (SDL_Rect) { 0, 0, 16, 16 };
	m->stats = (Stats) { 12, 12, 1, 0, 0, 1, 1 };
	m->state.normal = PASSIVE;
	m->state.challenge = AGRESSIVE;
	m->state.current = m->state.normal;
	m->label = NULL;
	m->lclabel = NULL;

	monster_load_texts(m, renderer);

	return m;
}

void
monster_update_pos(Monster *m, Position pos)
{
	m->sprite->pos = pos;

	Position textPos = pos;
	textPos.y += 10;
	m->hitText->pos = textPos;
	m->missText->pos = textPos;
}

static bool
has_collided(Monster *monster, RoomMatrix *matrix)
{
	if (!position_in_room(&monster->sprite->pos, &matrix->roomPos))
		return true;

	Position roomPos = position_to_matrix_coords(&monster->sprite->pos);
	RoomSpace *space = &matrix->spaces[roomPos.x][roomPos.y];

	if (space->player && monster->state.current == AGRESSIVE) {
		unsigned int dmg = stats_fight(&monster->stats,
					       &space->player->stats);

		player_hit(space->player, dmg);

		if (dmg > 0)
			gui_log("%s hit you for %u damage", monster->label, dmg);
		else
			gui_log("%s missed you", monster->label);
	}

	return space->occupied;
}

static bool
move_left(Monster *m, RoomMatrix *rm)
{
	m->sprite->pos.x -= TILE_DIMENSION;
	if (has_collided(m, rm)) {
	    m->sprite->pos.x += TILE_DIMENSION;
	    return false;
	}
	return true;
}

static bool
move_right(Monster *m, RoomMatrix *rm)
{
	m->sprite->pos.x += TILE_DIMENSION;
	if (has_collided(m, rm)) {
	    m->sprite->pos.x -= TILE_DIMENSION;
	    return false;
	}
	return true;
}

static bool
move_up(Monster *m, RoomMatrix *rm)
{
	m->sprite->pos.y -= TILE_DIMENSION;
	if (has_collided(m, rm)) {
	    m->sprite->pos.y += TILE_DIMENSION;
	    return false;
	}
	return true;
}

static bool
move_down(Monster *m, RoomMatrix *rm)
{
	m->sprite->pos.y += TILE_DIMENSION;
	if (has_collided(m, rm)) {
	    m->sprite->pos.y -= TILE_DIMENSION;
	    return false;
	}
	return true;
}

static void
monster_drunk_walk(Monster *m, RoomMatrix *rm)
{
	unsigned int i, maxMoveAttempts = 6;

	if (get_random(5) >= 2)
		return;

	for (i = 0; i < maxMoveAttempts; ++i) {
		int move = get_random(3);
		if (move == 0 && move_left(m, rm))
			break;
		else if (move == 1 && move_right(m, rm))
			break;
		else if (move == 2 && move_up(m, rm))
			break;
		else if (move == 3 && move_down(m, rm))
			break;
	}
}

static void
monster_agressive_walk(Monster *m, RoomMatrix *rm)
{
	int x_dist, y_dist;
	Position mPos;

	mPos = position_to_matrix_coords(&m->sprite->pos);

	x_dist = mPos.x - rm->playerRoomPos.x;
	y_dist = mPos.y - rm->playerRoomPos.y;


	if (abs(x_dist) > abs(y_dist)) {
		if (x_dist > 0)
			move_left(m, rm);
		else
			move_right(m, rm);
	} else {
		if (y_dist > 0)
			move_up(m, rm);
		else
			move_down(m, rm);
	}
}

static void
monster_coward_walk(Monster *m, RoomMatrix *rm)
{
	int x_dist, y_dist;
	Position mPos;

	mPos = position_to_matrix_coords(&m->sprite->pos);

	x_dist = mPos.x - rm->playerRoomPos.x;
	y_dist = mPos.y - rm->playerRoomPos.y;


	if (abs(x_dist) > abs(y_dist)) {
		if (x_dist > 0)
			move_right(m, rm);
		else
			move_left(m, rm);
	} else {
		if (y_dist > 0)
			move_down(m, rm);
		else
			move_up(m, rm);
	}
}

void
monster_move(Monster *m, RoomMatrix *rm)
{
	Position monsterRoomPos;

	monsterRoomPos = position_to_matrix_coords(&m->sprite->pos);
	rm->spaces[monsterRoomPos.x][monsterRoomPos.y].occupied = false;
	rm->spaces[monsterRoomPos.x][monsterRoomPos.y].monster = NULL;

	switch (m->state.current) {
		case PASSIVE:
			monster_drunk_walk(m, rm);
			break;
		case AGRESSIVE:
			monster_agressive_walk(m, rm);
			break;
		case SCARED:
			monster_coward_walk(m, rm);
			break;
	};

	monster_update_pos(m, m->sprite->pos);

	monsterRoomPos = position_to_matrix_coords(&m->sprite->pos);
	rm->spaces[monsterRoomPos.x][monsterRoomPos.y].occupied = true;
	rm->spaces[monsterRoomPos.x][monsterRoomPos.y].monster = m;
}

void
monster_hit(Monster *monster, unsigned int dmg)
{
	if (dmg > 0) {
		monster->hitText->active = true;
		monster->missText->active = false;
		Position p = monster->sprite->pos;
		p.x += 8;
		p.y += 8;
		Dimension d = { 8, 8 };
		particle_engine_bloodspray(p, d, dmg);
	} else {
		monster->missText->active = true;
		monster->hitText->active = false;
	}

	monster->state.current = monster->state.challenge;
}

void
monster_update_stats_for_level(Monster *m, unsigned int level)
{
	m->stats.lvl = level;
	m->stats.maxhp *= level;
	m->stats.hp = m->stats.maxhp;
	m->stats.dmg *= level;
	m->stats.atk *= level;
	m->stats.def *= level;
}

void
monster_drop_loot(Monster *monster, Map *map)
{
	static unsigned int item_drop_chance = 1;
	static unsigned int treasure_drop_chance = 1;
	Item *item;
	Item *items[2];
	unsigned int item_count = 0;

	if (get_random(treasure_drop_chance) == 0) {
		item = item_builder_build_item(TREASURE, map->level);
		item->sprite->pos = monster->sprite->pos;
		items[item_count++] = item;
	}
	if (get_random(item_drop_chance) == 0) {
		item = item_builder_build_item(get_random(TREASURE - 1), map->level);
		item->sprite->pos = monster->sprite->pos;
		items[item_count++] = item;
	}

	if (item_count == 0)
		return;

	gui_log("%s dropped something", monster->label);

	if (item_count == 1) {
		linkedlist_append(&map->items, items[0]);
	} else {
		Item *container = item_builder_build_sack();
		container->sprite->pos = monster->sprite->pos;
		unsigned int i;
		for (i = 0; i < item_count; ++i) {
			linkedlist_append(&container->items, items[i]);
		}
		linkedlist_append(&map->items, container);
	}
}

void
monster_render(Monster *m, Camera *cam)
{
	sprite_render(m->sprite, cam);
	if (m->hitText)
		actiontext_render(m->hitText, cam);
	if (m->missText)
		actiontext_render(m->missText, cam);
}

void
monster_destroy(Monster *m)
{
	sprite_destroy(m->sprite);
	if (m->label)
		free(m->label);
	if (m->lclabel)
		free(m->lclabel);
	if (m->hitText)
		actiontext_destroy(m->hitText);
	if (m->missText)
		actiontext_destroy(m->missText);
	free(m);
}