use std::{collections::HashMap, fs::read_dir, path::PathBuf};

use raylib::prelude::*;

#[derive(Default)]
pub struct Textures {
	map: HashMap<String, Texture2D>,
}

impl Textures {
	pub fn load_dir(&mut self, folder: &str, rl: &mut RaylibHandle, thread: &RaylibThread) {
		for d in read_dir(folder).unwrap().flatten() {
			let path = d.path();
			if path.is_file() {
				let name = path.file_stem().unwrap().to_string_lossy();
				let texture = rl
					.load_texture(thread, &format!("{folder}/{name}.png"))
					.unwrap();
				self.map.insert(name.to_string(), texture);
			}
		}
	}

	pub fn get(&self, name: &str) -> &Texture2D {
		self.map
			.get(name)
			.unwrap_or_else(|| self.map.get("missing").unwrap())
	}
}

pub fn simple_button(d: &mut RaylibDrawHandle, x: i32, y: i32, width: i32, height: i32) -> bool {
	let mouse_pos = d.get_mouse_position();
	let bounds = Rectangle {
		x: x as f32,
		y: y as f32,
		width: width as f32,
		height: height as f32,
	};
	let mut pressed = false;
	let color = if bounds.check_collision_point_rec(mouse_pos) {
		if d.is_mouse_button_pressed(MouseButton::MOUSE_BUTTON_LEFT) {
			pressed = true;
		}
		Color::DARKCYAN
	} else {
		Color::GRAY
	};
	d.draw_rectangle(x, y, width, height, color);
	pressed
}

pub fn simple_option_button<T>(
	d: &mut RaylibDrawHandle,
	x: i32,
	y: i32,
	width: i32,
	height: i32,
	option: T,
	current: &mut T,
) -> bool
where
	T: PartialEq,
{
	let color = if &option == current {
		Color::DARKCYAN
	} else {
		Color::GRAY
	};
	let bounds = Rectangle {
		x: x as f32,
		y: y as f32,
		width: width as f32,
		height: height as f32,
	};
	let mouse_pos = d.get_mouse_position();
	let mut changed = false;
	if d.is_mouse_button_pressed(MouseButton::MOUSE_BUTTON_LEFT)
		&& bounds.check_collision_point_rec(mouse_pos)
		&& current != &option
	{
		*current = option;
		changed = true;
	}
	d.draw_rectangle_rec(bounds, color);
	changed
}

pub fn text_input(
	d: &mut RaylibDrawHandle,
	bounds: Rectangle,
	text: &mut String,
	is_selected: &mut bool,
	max_len: usize,
	editable: bool,
) -> bool {
	let mut changed = false;
	let (bg, underline) = if *is_selected {
		(Color::DARKCYAN, Color::CYAN)
	} else {
		(Color::GRAY, Color::DIMGRAY)
	};
	d.draw_rectangle_rec(bounds, bg);
	d.draw_rectangle_rec(
		Rectangle::new(
			bounds.x + 2.,
			bounds.y + bounds.height - 5.,
			bounds.width - 4.,
			3.,
		),
		underline,
	);
	let drawn_text = if *is_selected {
		&format!("{text}_")
	} else {
		text.as_str()
	};
	d.draw_text(
		drawn_text,
		bounds.x as i32 + 4,
		bounds.y as i32 + 4,
		20,
		Color::WHITE,
	);
	let mouse_pos = d.get_mouse_position();
	if editable
		&& d.is_mouse_button_pressed(MouseButton::MOUSE_BUTTON_LEFT)
		&& (bounds.check_collision_point_rec(mouse_pos) || *is_selected)
	{
		*is_selected = !*is_selected;
	}

	if *is_selected {
		if d.is_key_pressed(KeyboardKey::KEY_ESCAPE) {
			*is_selected = false;
		}
		if d.is_key_pressed(KeyboardKey::KEY_BACKSPACE) && !text.is_empty() {
			changed = true;
			text.pop();
		}
		if text.len() < max_len {
			let char_code = unsafe { ffi::GetCharPressed() };
			let c = if char_code > 0 {
				char::from_u32(char_code as u32)
			} else {
				None
			};
			if let Some(c) = c {
				changed = true;
				text.push(c);
			}
		}
	}
	changed
}

pub fn texture_option_button<T>(
	d: &mut RaylibDrawHandle,
	pos: Vector2,
	texture: &Texture2D,
	option: T,
	current: &mut T,
	tex_size: f32,
	border: f32,
	// tooltip
) where
	T: PartialEq,
{
	let color = if &option == current {
		Color::DARKCYAN
	} else {
		Color::GRAY
	};
	let bounds = Rectangle {
		x: pos.x,
		y: pos.y,
		width: tex_size + border * 2.,
		height: tex_size + border * 2.,
	};
	d.draw_rectangle_rec(bounds, color);
	d.draw_texture_ex(
		texture,
		pos + Vector2::new(border, border),
		0.,
		tex_size / texture.width as f32,
		Color::WHITE,
	);

	let mouse_pos = d.get_mouse_position();
	if d.is_mouse_button_pressed(MouseButton::MOUSE_BUTTON_LEFT)
		&& bounds.check_collision_point_rec(mouse_pos)
	{
		*current = option;
	}
}

pub fn draw_usize(
	d: &mut RaylibDrawHandle,
	textures: &Textures,
	number: usize,
	x: i32,
	y: i32,
	digits: u8,
	scale: u8,
) {
	let digits = digits as i32;
	let scale = scale as i32;
	for i in 0..digits {
		d.draw_rectangle(x + 10 * i * scale, y, 8 * scale, 16 * scale, Color::DIMGRAY);
	}
	let mut num = number;
	let mut i = 0;
	while (num != 0 || i == 0) && i < digits {
		let texture = textures.get(&format!("digit_{}", num % 10));
		let x = x + (digits - i - 1) * 10 * scale;
		draw_scaled_texture(d, texture, x, y, scale as f32);
		num /= 10;
		i += 1;
	}
}

pub fn draw_usize_small(
	d: &mut RaylibDrawHandle,
	textures: &Textures,
	mut num: usize,
	mut x: i32,
	y: i32,
	scale: f32,
) {
	const MAX_DIGITS: usize = 8;
	let mut digits = [0; MAX_DIGITS];
	let mut i = 0;
	while (num != 0 || i == 0) && i < MAX_DIGITS {
		digits[MAX_DIGITS - i - 1] = num % 10;
		num /= 10;
		i += 1;
	}
	let texture = textures.get("digits_small");
	for &digit in &digits[(MAX_DIGITS - i)..] {
		let source = Rectangle::new(4. * digit as f32, 0., 4., 6.);
		let dest = Rectangle::new(x as f32, y as f32, 4. * scale, 6. * scale);
		d.draw_texture_pro(texture, source, dest, Vector2::zero(), 0., Color::RED);
		x += 4 * scale as i32;
	}
}

pub fn slider(
	d: &mut RaylibDrawHandle,
	value: &mut u8,
	min: u8,
	max: u8,
	x: i32,
	y: i32,
	width: i32,
	height: i32,
) -> bool {
	// the +1 makes the lowest state look slightly filled and the max state fully filled
	let percent = (*value - min + 1) as f32 / (max - min + 1) as f32;
	d.draw_rectangle(x, y, width, height, Color::DIMGRAY);
	d.draw_rectangle(x, y, (width as f32 * percent) as i32, height, Color::CYAN);
	let mouse_pos = d.get_mouse_position();
	let bounds = Rectangle::new(x as f32, y as f32, width as f32, height as f32);
	if bounds.check_collision_point_rec(mouse_pos) {
		if d.is_mouse_button_down(MouseButton::MOUSE_BUTTON_LEFT) {
			let percent = (mouse_pos.x - bounds.x) / bounds.width;
			let new_value = min + (percent * (max - min + 1) as f32) as u8;
			if *value != new_value {
				*value = new_value
			}
		} else if d.get_mouse_wheel_move() > 0.5 && *value < max {
			*value += 1;
		} else if d.get_mouse_wheel_move() < -0.5 && *value > min {
			*value -= 1;
		}
	}
	false
}

pub fn userdata_dir() -> PathBuf {
	PathBuf::from("user")
}

pub fn draw_scaled_texture(
	d: &mut RaylibDrawHandle,
	texture: &Texture2D,
	x: i32,
	y: i32,
	scale: f32,
) {
	let pos = Vector2::new(x as f32, y as f32);
	d.draw_texture_ex(texture, pos, 0., scale, Color::WHITE);
}