use crate::Textures;

use super::tile::*;
use raylib::prelude::*;

#[derive(Debug, Default, Clone, Copy, PartialEq)]
pub struct Pos {
	pub x: isize,
	pub y: isize,
}

impl Pos {
	pub const fn to_vec(self) -> Vector2 {
		Vector2 {
			x: self.x as f32,
			y: self.y as f32,
		}
	}
}

impl From<(usize, usize)> for Pos {
	fn from(value: (usize, usize)) -> Self {
		Self {
			x: value.0 as isize,
			y: value.1 as isize,
		}
	}
}

impl From<Vector2> for Pos {
	fn from(vec: Vector2) -> Self {
		Self {
			x: vec.x as isize,
			y: vec.y as isize,
		}
	}
}

#[derive(Debug, Clone)]
pub struct Board {
	rows: Vec<Vec<Tile>>,
	width: usize,
	height: usize,
	offset_x: isize,
	offset_y: isize,
}

impl Board {
	pub fn parse(source: &str) -> Self {
		let mut rows = Vec::new();

		let mut width = 0;
		for line in source.lines() {
			width = width.max(line.len());
			let mut tiles = Vec::new();
			for char in line.chars() {
				tiles.push(Tile::from_char(char));
			}
			rows.push(tiles);
		}
		for line in &mut rows {
			line.resize(width, Tile::Blank);
		}

		Board::new(rows)
	}

	pub fn to_string(&self) -> String {
		let mut out = String::new();
		for row in &self.rows {
			for tile in row {
				out.push(tile.to_char())
			}
			out.push('\n');
		}
		out
	}

	pub fn new_empty(width: usize, height: usize) -> Self {
		let rows = vec![vec![Tile::Blank; width]; height];
		Self {
			rows,
			width,
			height,
			offset_x: 0,
			offset_y: 0,
		}
	}

	pub fn new(rows: Vec<Vec<Tile>>) -> Self {
		Self {
			width: rows[0].len(),
			height: rows.len(),
			rows,
			offset_x: 0,
			offset_y: 0,
		}
	}

	pub fn count_tiles(&self) -> usize {
		let mut sum = 0;
		for row in &self.rows {
			for tile in row {
				match tile {
					Tile::Blank | Tile::Block => (),
					_ => sum += 1,
				}
			}
		}
		sum
	}

	fn transform(&self, p: Pos) -> Pos {
		Pos {
			x: p.x + self.offset_x,
			y: p.y + self.offset_y,
		}
	}

	pub fn pos_in_bounds(&self, p: Pos) -> bool {
		let p = self.transform(p);
		self.in_bounds(p)
	}

	fn in_bounds(&self, p: Pos) -> bool {
		p.x >= 0 && p.y >= 0 && p.x < self.width as isize && p.y < self.height as isize
	}

	pub fn get(&self, p: Pos) -> Option<Tile> {
		let p = self.transform(p);
		if self.in_bounds(p) {
			Some(self.rows[p.y as usize][p.x as usize])
		} else {
			None
		}
	}

	pub fn get_or_blank(&self, p: Pos) -> Tile {
		let p = self.transform(p);
		if self.in_bounds(p) {
			self.rows[p.y as usize][p.x as usize]
		} else {
			Tile::default()
		}
	}

	pub fn get_mut(&mut self, p: Pos) -> Option<&mut Tile> {
		let p = self.transform(p);
		if self.in_bounds(p) {
			Some(&mut self.rows[p.y as usize][p.x as usize])
		} else {
			None
		}
	}

	pub fn get_blank_mut(&mut self, p: Pos) -> Option<&mut Tile> {
		let p = self.transform(p);
		if self.in_bounds(p) {
			let tile = &mut self.rows[p.y as usize][p.x as usize];
			if tile == &Tile::Blank {
				return Some(tile);
			}
		}
		None
	}

	pub fn set(&mut self, p: Pos, tile: Tile) {
		let p = self.transform(p);
		if self.in_bounds(p) {
			self.rows[p.y as usize][p.x as usize] = tile;
		}
	}

	pub fn grow_to_include(&mut self, p: Pos) {
		let p = self.transform(p);
		if p.x < 0 {
			let len = p.x.unsigned_abs();
			for row in &mut self.rows {
				let mut new_row = vec![Tile::Blank; len];
				new_row.append(row);
				*row = new_row;
			}
			self.offset_x += len as isize;
			self.width += len;
		} else if p.x as usize >= self.width {
			let new_width = p.x as usize + 1;
			for row in &mut self.rows {
				row.resize(new_width, Tile::Blank);
			}
			self.width = new_width;
		}

		if p.y < 0 {
			let len = p.y.unsigned_abs();
			let mut new_rows = vec![vec![Tile::Blank; self.width]; len];
			new_rows.append(&mut self.rows);
			self.rows = new_rows;
			self.offset_y += len as isize;
			self.height += len;
		} else if p.y as usize > self.height {
			let new_height = p.y as usize + 1;
			self.rows.resize(new_height, vec![Tile::Blank; self.width]);
			self.height = new_height;
		}
	}

	pub fn width(&self) -> usize {
		self.width
	}

	pub fn height(&self) -> usize {
		self.height
	}

	pub fn draw(&self, d: &mut RaylibDrawHandle, textures: &Textures, offset: Vector2, zoom: i32) {
		let tile_size = 16 << zoom;

		let start_x = (-offset.x as i32) / tile_size - 1;
		let tile_width = d.get_screen_width() / tile_size + 2;
		let start_y = (-offset.y as i32) / tile_size - 1;
		let tile_height = d.get_screen_height() / tile_size + 2;

		for x in start_x..(start_x + tile_width) {
			for y in start_y..(start_y + tile_height) {
				let tx = (x as isize + self.offset_x) as usize;
				let ty = (y as isize + self.offset_y) as usize;
				if self.in_bounds((tx, ty).into()) {
					let tile = self.rows[ty][tx];
					let texname = tile.texture();
					if texname == "" {
						continue;
					}
					let texture = textures.get(&texname);
					let px = x * tile_size + offset.x as i32;
					let py = y * tile_size + offset.y as i32;
					d.draw_texture_ex(
						texture,
						Vector2::new(px as f32, py as f32),
						0.0,
						(1 << zoom) as f32,
						Color::WHITE,
					);
				}
			}
		}
	}
}