use dungeon::{
	Dungeon, UpdateResult, entity::PLAYER_INVENTORY_SIZE, player_input::PlayerInput,
	pos::Direction,
};
use graphics::{Key, Window};

pub struct Game {
	window: Window,
	dungeon: Dungeon,
	// to ensure the most recently-pressed direction key is used:
	current_dir: Option<(Direction, Key)>,
}

impl Game {
	pub fn new(window: Window, seed: Option<u64>) -> Self {
		let dungeon = match seed {
			Some(s) => Dungeon::new(s),
			None => Dungeon::random(),
		};

		Self {
			window,
			dungeon,
			current_dir: None,
		}
	}

	fn player_dir(&mut self) -> Option<Direction> {
		const MOVE_KEYS: [(Direction, [Key; 2]); 4] = [
			(Direction::North, [Key::Up, Key::W]),
			(Direction::West, [Key::Left, Key::A]),
			(Direction::South, [Key::Down, Key::S]),
			(Direction::East, [Key::Right, Key::D]),
		];

		// if a key was just pressed, use it for the new direction to move in
		for (dir, keys) in MOVE_KEYS {
			for key in keys {
				if self.window.is_key_pressed(key) {
					self.current_dir = Some((dir, key));
					return Some(dir);
				}
			}
		}
		// otherwise, use existing direction, so long as the key is still down
		match self.current_dir {
			Some((dir, key)) if self.window.is_key_down(key) => return Some(dir),
			_ => self.current_dir = None,
		}
		// otherwise, use any key that is already down
		for (dir, keys) in MOVE_KEYS {
			for key in keys {
				if self.window.is_key_down(key) {
					self.current_dir = Some((dir, key));
					return Some(dir);
				}
			}
		}
		// otherwise, no direction key is pressed, so return None
		None
	}

	fn get_player_input(&mut self) -> PlayerInput {
		let direction = self.player_dir();
		let interact = self.window.is_key_pressed(Key::Return);
		let use_item = self.window.is_key_pressed(Key::E);
		let attack = self.window.is_key_pressed(Key::F);
		let drop = self.window.is_key_pressed(Key::Q);
		let inv_slot = (0..PLAYER_INVENTORY_SIZE)
			.filter_map(|u16| u8::try_from(u16).ok())
			.find(|u8| self.window.is_key_pressed(Key::Number(*u8 + 1)))
			.map(|u8| u8 as usize);
		PlayerInput {
			direction,
			interact,
			use_item,
			attack,
			drop,
			inv_slot,
		}
	}

	pub fn run(&mut self) {
		// Main game loop
		while self.window.is_open() {
			// Handle debug keys
			if self.window.is_key_pressed(Key::F3) {
				self.window.toggle_debug();
			}
			if self.window.is_key_pressed(Key::F4) {
				self.dungeon.player.entity.health = 0;
			}

			// Update game state
			let inputs = self.get_player_input();
			let result = self
				.dungeon
				.update(inputs, self.window.delta_time().as_secs_f32());
			match result {
				UpdateResult::Default(_action) => {
					// TODO: make noises for player actions
				}
				UpdateResult::NextFloor => {
					// TODO: stairs audio
				}
				UpdateResult::MessageUpdated(changed) => {
					if changed {
						self.window.audio().speak.play();
					}
				}
				UpdateResult::GameOver => {
					// TODO: player game over music, very sad
				}
				UpdateResult::Nothing => {}
			}

			// Draw a single frame
			self.window.draw_frame(&self.dungeon);
		}
	}
}