/*
 * 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 <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "player.h"
#include "monster.h"
#include "util.h"
#include "gui.h"
#include "item.h"
#include "particle_engine.h"
#include "keyboard.h"
#include "mixer.h"
#include "random.h"
#include "projectile.h"
#include "texturecache.h"
#include "vector2d.h"
#include "actiontextbuilder.h"

#define ENGINEER_STATS	{ 12, 12, 5, 7, 2, 2, 1 }
#define MAGE_STATS	{ 12, 12, 5, 7, 1, 2, 1 }
#define PALADIN_STATS	{ 12, 12, 8, 9, 3, 1, 1 }
#define ROGUE_STATS	{ 12, 12, 5, 7, 1, 2, 1 }
#define WARRIOR_STATS	{ 12, 12, 8, 9, 3, 1, 1 }

static void
player_levelup(Player *player)
{
	mixer_play_effect(LEVEL_UP);

	player->stats.lvl += 1;
	player->stats.maxhp += 9;
	player->stats.dmg += 5;
	player->stats.atk += 1;

	// Limit health to 3 rows of hearts
	if (player->stats.maxhp > 72)
		player->stats.maxhp = 72;

	player->stats.hp = player->stats.maxhp;
}

static unsigned int
next_level_threshold(unsigned int current_level)
{
	unsigned int last_level = 0;
	unsigned int padding = 0;

	if (current_level > 0) {
		last_level = next_level_threshold(current_level - 1);
		padding = (current_level - 1) * 150;
	}

	return last_level + (current_level * 50) + padding;
}

static void
player_gain_xp(Player *player, unsigned int xp_gain)
{
	static SDL_Color c_green = { 0, 255, 0, 255 };
	char msg[10];
	m_sprintf(msg, 5, "+%dxp", xp_gain);
	actiontextbuilder_create_text(msg, c_green, &player->sprite->pos);

	player->xp += xp_gain;
	if (player->xp >= next_level_threshold(player->stats.lvl)) {
		player_levelup(player);
		gui_log("You have reached level %u", player->stats.lvl);
		gui_event_message("You reached level %u", player->stats.lvl);
		actiontextbuilder_create_text("Level up", c_green, &player->sprite->pos);
	}
}

static void
action_spent(Player *p)
{
	p->stat_data.steps++;
	p->stat_data.total_steps++;

	for (size_t i = 0; i < PLAYER_SKILL_COUNT; ++i) {
		if (p->skills[i] != NULL && p->skills[i]->resetCountdown > 0)
			p->skills[i]->resetCountdown--;
	}
}

static void
player_step(Player *p)
{
	action_spent(p);
}

static bool 
has_collided(Player *player, RoomMatrix *matrix, Vector2d direction)
{
	bool collided = false;

	Position roomCoord = position_to_room_coords(&player->sprite->pos);
	if (roomCoord.x != matrix->roomPos.x
	    || roomCoord.y != matrix->roomPos.y) {
		return collided;
	}

	Position matrixPos = position_to_matrix_coords(&player->sprite->pos);
	RoomSpace *space = &matrix->spaces[matrixPos.x][matrixPos.y];
	collided = space->occupied;

	if (space->monster != NULL) {
		unsigned int hit = stats_fight(&player->stats,
					       &space->monster->stats);

		mixer_play_effect(SWING0 + get_random(2));

		monster_hit(space->monster, hit);

		if (hit > 0) {
			gui_log("You hit %s for %u damage",
				space->monster->lclabel, hit);
			player->stat_data.hits += 1;
			mixer_play_effect(SWORD_HIT);
		} else {
			gui_log("You missed %s", space->monster->lclabel);
			player->stat_data.misses += 1;
		}

		player_monster_kill_check(player, space->monster);

		action_spent(player);

	} else if (collided) {
		mixer_play_effect(BONK);
		camera_shake(direction, 100);
		gui_log("Ouch! There is something in the way");
	}

	if (space->items != NULL && !collided) {
		LinkedList *items = space->items;
		while (items != NULL) {
			Item *item = items->data;
			items = items->next;
			item_collected(item, player);
		}
	}

	if (space->lethal && !collided) {
		mixer_play_effect(FALL);
		player->state = FALLING;
	}

	return collided;
}

static void
set_clip_for_direction(Player *player, Vector2d *direction)
{
	if (vector2d_equals(*direction, VECTOR2D_LEFT))
		player->sprite->clip.y = 16;
	else if (vector2d_equals(*direction, VECTOR2D_RIGHT))
		player->sprite->clip.y = 32;
	else if (vector2d_equals(*direction, VECTOR2D_UP))
		player->sprite->clip.y = 48;
	else if (vector2d_equals(*direction, VECTOR2D_DOWN))
		player->sprite->clip.y = 0;
}

static void
move(Player *player, RoomMatrix *matrix, Vector2d direction)
{
	set_clip_for_direction(player, &direction);
	player->sprite->pos.x += TILE_DIMENSION * (int) direction.x;
	player->sprite->pos.y += TILE_DIMENSION * (int) direction.y;
	if (has_collided(player, matrix, direction)) {
		player->sprite->pos.x -= TILE_DIMENSION * (int) direction.x;
		player->sprite->pos.y -= TILE_DIMENSION * (int) direction.y;
	} else {
		player_step(player);
	}
}

void
player_sip_health(Player *player)
{
	if (player->potion_sips > 0) {
		--player->potion_sips;
		++player->stats.hp;
		mixer_play_effect(BUBBLE0 + get_random(2));
		gui_log("You take a sip of health potion");
	} else {
		gui_log("You have nothing to sip");
	}
}

static void
handle_movement_input(Player *player, RoomMatrix *matrix, SDL_Event *event)
{
	static unsigned int step = 1;
	Vector2d direction = VECTOR2D_NODIR;

	if (keyboard_direction_press(LEFT, event))
		direction = VECTOR2D_LEFT;
	if (keyboard_direction_press(RIGHT, event))
		direction = VECTOR2D_RIGHT;
	if (keyboard_direction_press(UP, event))
		direction = VECTOR2D_UP;
	if (keyboard_direction_press(DOWN, event))
		direction = VECTOR2D_DOWN;

	if (!vector2d_equals(direction, VECTOR2D_NODIR))
		move(player, matrix, direction);

	map_room_modifier_player_effect(player, matrix, &direction, move);


#ifdef DEBUG
	if (keyboard_mod_press(SDLK_SPACE, KMOD_CTRL, event)) {
		Position pos = player->sprite->pos;
		pos.x += 8;
		pos.y += 8;
		particle_engine_bloodspray(pos, (Dimension) { 8, 8 }, 200);
		player->stats.hp = 0;
	}
#endif // DEBUG

	if (!vector2d_equals(VECTOR2D_NODIR, direction)) {
		player->sprite->clip.x = 16*step;
		++step;
		step = step % 4;
	}
}

static void
use_skill(Skill *skill, SkillData *skillData)
{
	skill->active = false;
	skill->use(skill, skillData);
	if (skill->actionRequired)
		player_step(skillData->player);
	skill->resetCountdown = skill->resetTime;
}

static void
check_skill_activation(Player *player, RoomMatrix *matrix, SDL_Event *event)
{
	// TODO(Linus): This could be "smarter"
	unsigned int selected = 0;
	if (keyboard_press(SDLK_1, event)) {
		selected = 1;
	} else if (keyboard_press(SDLK_2, event)) {
		selected = 2;
	} else if (keyboard_press(SDLK_3, event)) {
		selected = 3;
	} else if (keyboard_press(SDLK_4, event)) {
		selected = 4;
	} else if (keyboard_press(SDLK_5, event)) {
		selected = 5;
	}

	if (selected == 0)
		return;

	for (size_t i = 0; i < PLAYER_SKILL_COUNT; ++i) {
		if (!player->skills[i])
			continue;

		Skill *skill = player->skills[i];
		if (skill->levelcap > player->stats.lvl)
			continue;
		if (skill->available && !skill->available(player))
			continue;
		skill->active = (selected - 1) == i && !skill->active && skill->resetCountdown == 0;
		if (skill->active && skill->instantUse) {
			SkillData skillData = { player, matrix, VECTOR2D_NODIR };
			use_skill(skill, &skillData);
		}
	}
}

static bool
check_skill_trigger(Player *player, RoomMatrix *matrix, SDL_Event *event)
{
	int activeSkill = -1;
	for (int i = 0; i < PLAYER_SKILL_COUNT; ++i) {
		if (player->skills[i] && player->skills[i]->active) {
			activeSkill = i;
			break;
		}
	}

	if (activeSkill < 0)
		return false;

	Vector2d dir;
	if (keyboard_direction_press(UP, event))
		dir = VECTOR2D_UP;
	else if (keyboard_direction_press(DOWN, event))
		dir = VECTOR2D_DOWN;
	else if (keyboard_direction_press(LEFT, event))
		dir = VECTOR2D_LEFT;
	else if (keyboard_direction_press(RIGHT, event))
		dir = VECTOR2D_RIGHT;
	else
		return false;

	SkillData skillData = { player, matrix, dir };
	use_skill(player->skills[activeSkill], &skillData);

	return true;
}

static void
handle_player_input(Player *player, RoomMatrix *matrix, SDL_Event *event)
{
	if (player->state != ALIVE)
		return;

	if (event->type != SDL_KEYDOWN)
		return;

	if (player->projectiles)
		return;

	check_skill_activation(player, matrix, event);
	if (!check_skill_trigger(player, matrix, event))
		handle_movement_input(player, matrix, event);
}

Player* 
player_create(class_t class, SDL_Renderer *renderer)
{
	Player *player = malloc(sizeof(Player));
	player->sprite = sprite_create();
	player->daggers			= 0;
	player->stat_data.total_steps	= 0;
	player->stat_data.steps		= 0;
	player->stat_data.hits		= 0;
	player->stat_data.kills		= 0;
	player->stat_data.misses	= 0;
	player->xp			= 0;
	player->gold			= 0;
	player->potion_sips		= 0;
	player->class			= class;
	player->state			= ALIVE;
	player->projectiles		= linkedlist_create();
	player->animationTimer		= timer_create();

	for (size_t i = 0; i < PLAYER_SKILL_COUNT; ++i) {
		player->skills[i] = NULL;
	}

	char asset[100];
	switch (class) {
		case ENGINEER:
			m_strcpy(asset, 100, "Commissions/Engineer.png");
			player->stats = (Stats) ENGINEER_STATS;
			break;
		case MAGE:
			m_strcpy(asset, 100, "Commissions/Mage.png");
			player->stats = (Stats) MAGE_STATS;
			break;
		case PALADIN:
			m_strcpy(asset, 100, "Commissions/Paladin.png");
			player->stats = (Stats) PALADIN_STATS;
			break;
		case ROGUE:
			m_strcpy(asset, 100, "Commissions/Rogue.png");
			player->stats = (Stats) ROGUE_STATS;
			break;
		case WARRIOR:
			m_strcpy(asset, 100, "Commissions/Warrior.png");
			player->stats = (Stats) WARRIOR_STATS;
			player->skills[0] = skill_create(FLURRY);
			player->skills[1] = skill_create(CHARGE);
			player->skills[2] = skill_create(DAGGER_THROW);
			break;
	}

	player->skills[4] = skill_create(SIP_HEALTH);

	sprite_load_texture(player->sprite, asset, 0, renderer);
	player->sprite->pos = (Position) { TILE_DIMENSION, TILE_DIMENSION };
	player->sprite->dim = GAME_DIMENSION;
	player->sprite->clip = (SDL_Rect) { 0, 0, 16, 16 };
	player->handle_event = &handle_player_input;

	return player;
}

ExperienceData player_get_xp_data(Player *p)
{
	ExperienceData data;
	data.previousLevel = next_level_threshold(p->stats.lvl - 1);
	data.current = p->xp;
	data.nextLevel = next_level_threshold(p->stats.lvl);
	data.level = p->stats.lvl;
	return data;
}

void
player_monster_kill_check(Player *player, Monster *monster)
{
	if (!monster)
		return;

	if (monster->stats.hp <= 0) {
		unsigned int gained_xp = 5 * monster->stats.lvl;
		player->stat_data.kills += 1;
		mixer_play_effect(DEATH);
		gui_log("You killed %s and gained %d xp",
			monster->lclabel, gained_xp);
		player_gain_xp(player, gained_xp);
	}
}

void
player_hit(Player *p, unsigned int dmg)
{
	static SDL_Color c_red = { 255, 0, 0, 255 };
	static SDL_Color c_yellow = { 255, 255, 0, 255 };

	if (p->stats.hp <= 0) {
		dmg = 200;
	}
	if (dmg > 0) {
		Position pos = p->sprite->pos;
		pos.x += 8;
		pos.y += 8;
		particle_engine_bloodspray(pos, (Dimension) { 8, 8 }, dmg);
		mixer_play_effect(PLAYER_HIT0 + get_random(2));
		char msg[5];
		m_sprintf(msg, 5, "-%d", dmg);
		actiontextbuilder_create_text(msg,
					      c_red,
					      &p->sprite->pos);
	} else {
		actiontextbuilder_create_text("Dodged",
					      c_yellow,
					      &p->sprite->pos);
	}

}

void
player_render(Player *player, Camera *cam)
{
	sprite_render(player->sprite, cam);

	LinkedList *projectile = player->projectiles;
	while (projectile) {
		projectile_render(projectile->data, cam);
		projectile = projectile->next;
	}

}

void
player_reset_steps(Player *p)
{
	p->stat_data.steps = 0;
}

void player_update(UpdateData *data)
{
	Player *player = data->player;
	if (player->state == FALLING && player->stats.hp > 0) {
		if (!timer_started(player->animationTimer)) {
			timer_start(player->animationTimer);
			player->sprite->clip = CLIP16(0, 0);
		} else {
			if (timer_get_ticks(player->animationTimer) > 100) {
				timer_start(player->animationTimer);
				player->sprite->angle += 60;
				player->sprite->dim.width -= 4;
				player->sprite->dim.height -= 4;
				player->sprite->pos.x += 2;
				player->sprite->pos.y += 2;
				player->sprite->rotationPoint = (SDL_Point) {
					player->sprite->dim.width /2,
					player->sprite->dim.height /2
				};
				if (player->sprite->dim.width <= 4)
					player->stats.hp = 0;
			}
		}
	}

	LinkedList *remaining = linkedlist_create();
	while (player->projectiles) {
		Projectile *p = linkedlist_pop(&player->projectiles);
		projectile_update(p, data);
		if (p->alive) {
			linkedlist_push(&remaining, p);
		} else {
			projectile_destroy(p);
			action_spent(player);
		}
	}

	linkedlist_destroy(&player->projectiles);
	player->projectiles = remaining;
}

void
player_destroy(Player *player)
{
	if (player->sprite)
		sprite_destroy(player->sprite);

	timer_destroy(player->animationTimer);

	for (size_t i = 0; i < PLAYER_SKILL_COUNT; ++i) {
		if (player->skills[i])
			skill_destroy(player->skills[i]);
		player->skills[i] = NULL;
	}

	while (player->projectiles)
		projectile_destroy(linkedlist_pop(&player->projectiles));

	free(player);
}