use common::Point2D;
use common::Radians;
use sdl2::HapticSubsystem;
use sdl2::JoystickSubsystem;
use sdl2::event::Event;
use sdl2::haptic::Haptic;
use sdl2::joystick::Joystick;
use std::cell::RefCell;
use std::collections::HashMap;
use std::rc::Rc;
use time::{Duration, prelude::*};

#[derive(Debug, Default)]
pub struct Button {
    pub time_pressed: Duration,
    pub time_released: Duration,
    pub is_pressed: bool,
    pub was_pressed: bool,
    pub toggle: bool,
}

impl Button {
    fn update(&mut self, device: &Joystick, dt: Duration, btn: u8) {
	self.was_pressed = self.is_pressed;
	self.is_pressed = match device.button(btn as u32) {
	    Ok(true) => {
		if !self.was_pressed {
		    self.time_pressed = 0.seconds();
		    self.toggle = !self.toggle;
		}
		self.time_pressed += dt;
		true
	    }
	    Ok(false) => {
		if self.was_pressed {
		    self.time_released = 0.seconds();
		}
		self.time_released += dt;
		false
	    }
	    Err(_) => { panic!("invalid button {}", btn) }
	}
    }
}

#[derive(Debug, Default)]
pub struct Axis {
    pub val: f32,
}

impl Axis {
    #[allow(dead_code)]
    fn update(&mut self, device: &Joystick, _dt: Duration, axis: u8) {
	self.val = match device.axis(axis as u32) {
	    Ok(val) => val as f32 / 32768.0,
	    Err(_) => panic!("invalid axis {}", axis),
	}
    }
}

#[derive(Debug, Default)]
pub struct Stick {
    pub x: f32,
    pub y: f32,
    pub a: Radians,
    pub len: f32,
}

impl Stick {
    fn update(&mut self, device: &Joystick, _dt: Duration, x_axis: u8, y_axis: u8) {
	self.x = match device.axis(x_axis as u32) {
	    Ok(val) => val as f32 / 32768.0,
	    Err(_) => panic!("invalid x axis {}", x_axis),
	};
	self.y = match device.axis(y_axis as u32) {
	    Ok(val) => val as f32 / 32768.0,
	    Err(_) => panic!("invalid y axis {}", y_axis),
	};
	self.a = Radians(self.y.atan2(self.x) as f64);
	self.len = {
	    let x = (self.x / self.y).abs().min(1.0);
	    let y = (self.y / self.x).abs().min(1.0);
	    (self.x.powi(2) + self.y.powi(2)).sqrt() / (x.powi(2) + y.powi(2)).sqrt()
	}
    }

    #[inline(always)] #[allow(dead_code)] fn up(&self) -> bool { self.y > 0.99 }
    #[inline(always)] #[allow(dead_code)] fn down(&self) -> bool { self.y < -0.99 }
    #[inline(always)] #[allow(dead_code)] fn left(&self) -> bool { self.x < -0.99 }
    #[inline(always)] #[allow(dead_code)] fn right(&self) -> bool { self.x > 0.99 }

    pub fn to_point(&self) -> Point2D<f64> {
	Point2D {
	    x: self.x as f64,
	    y: self.y as f64,
	}
    }

    pub fn to_adjusted_point(&self) -> Point2D<f64> {
	Point2D::from(self.a) * self.len as f64
    }
}

impl From<&Stick> for Point2D<f64> {
    fn from(item: &Stick) -> Self {
	Self {
	    x: item.x as f64,
	    y: item.y as f64,
	}
    }
}

impl From<&Stick> for (f64, f64) {
    fn from(item: &Stick) -> Self {
	(item.x as f64, item.y as f64)
    }
}

//#[derive(Debug)]
pub struct Controller {
    pub device: Joystick,
    haptic: Option<Rc<RefCell<Haptic>>>,

    pub mov: Stick,
    pub aim: Stick,
    pub jump: Button,
    pub start: Button,
    pub shoot: Button,
}

impl Controller {
    pub fn new(device: Joystick, haptic: Option<Rc<RefCell<Haptic>>>) -> Self {
	Controller {
	    device,
	    haptic,
	    mov: Default::default(),
	    aim: Default::default(),
	    jump: Default::default(),
	    start: Default::default(),
	    shoot: Default::default(),
	}
    }

    pub fn update(&mut self, dt: Duration) {
	self.mov.update(&self.device, dt, 0, 1); // left stick
	self.aim.update(&self.device, dt, 3, 4); // right stick
	self.jump.update(&self.device, dt, 4);	 // left shoulder
	self.shoot.update(&self.device, dt, 5); // right shoulder
	self.start.update(&self.device, dt, 9);	 // start
    }

    /// strength [0 - 1]
    pub fn rumble(&self, strength: f32, duration: Duration) {
	if let Some(h) = &self.haptic {
	    h.borrow_mut().rumble_play(strength, duration.whole_milliseconds() as u32);
	}
    }
}

//#[derive(Debug)]
pub struct ControllerManager {
    pub joystick: JoystickSubsystem,
    haptic: Rc<HapticSubsystem>,
    pub controllers: HashMap<u32, Rc<RefCell<Controller>>>,
}

impl ControllerManager {
    pub fn new(joystick: JoystickSubsystem, haptic: HapticSubsystem) -> Self {
	joystick.set_event_state(true);
	let mut c = ControllerManager {
	    joystick,
	    haptic: Rc::new(haptic),
	    controllers: HashMap::new(),
	};
	c.init();
	c
    }

    fn init(&mut self) {
	for i in 0..self.joystick.num_joysticks().unwrap() {
	    self.add_device(i);
	}
    }

    pub fn update(&mut self, dt: Duration) {
	self.controllers.iter().for_each(|(_, v)| v.borrow_mut().update(dt));
    }

    pub fn handle_event(&mut self, event: &Event) {
	match event {
	    Event::JoyDeviceAdded { which, .. } => { self.add_device(*which) }
	    Event::JoyDeviceRemoved { which, .. } => { self.remove_device(*which) }
	    Event::JoyButtonDown { which, button_idx, .. } => { println!("device {} button {} down!", which, button_idx) }
	    Event::JoyButtonUp { which, button_idx, .. } => { println!("device {} button {} up!", which, button_idx) }
	    Event::JoyAxisMotion { which, axis_idx, .. } => { println!("device {} axis motion {}!", which, axis_idx) }
	    _ => {}
	}
    }

    fn add_device(&mut self, id: u32) {
	println!("device added ({})!", id);
	let mut device = self.joystick.open(id).unwrap();
	println!("opened {}", device.name());

	/*
	note about set_rumble (for dualshock 3 at least):
	the active range for the low frequency is from 65536/4 to 65536 and escalates in large steps throughout the range
	the active range for the high frequency is from 256 to 65536 and effect is the same throughout the whole range
	 */
	let haptic = match device.set_rumble(0, 256, 100) {
	    Ok(_) => self.haptic.open_from_joystick_id(id).ok(),
	    Err(_) => None
	};

	if self.controllers.contains_key(&id) {
	    return;
	}

	let detached = self.controllers.values().find(|c| !c.borrow().device.attached());
	match detached {
	    Some(c) => {
		let mut c = c.borrow_mut();
		c.device = device;
		c.haptic = haptic.map(|h| Rc::new(RefCell::new(h)));
	    }
	    None => {
		let c = Rc::new(RefCell::new(Controller::new(device, haptic.map(|h| Rc::new(RefCell::new(h))))));
		self.controllers.insert(id, c);
	    }
	};
    }

    fn remove_device(&mut self, id: i32) {
	println!("device removed ({})!", id);
	// TODO
    }
}