use std::{
    marker::PhantomData,
    ops::{Add, AddAssign, Index, IndexMut, Sub, SubAssign},
};

use bevy::{
    ecs::component::Component,
    math::{Dir3, IVec3, InvalidDirectionError},
};

use super::Region;

pub struct Pos<T> {
    pub x: i32,
    pub y: i32,
    pub z: i32,
    _marker: PhantomData<T>,
}

impl<T> Pos<T> {
    pub const ORIGIN: Self = Self::new(0, 0, 0);

    pub const fn new(x: i32, y: i32, z: i32) -> Self {
        Self {
            x,
            y,
            z,
            _marker: PhantomData,
        }
    }

    pub fn region(self) -> Region<T> {
        Region::new_unchecked(self.into(), self.into())
    }

    pub fn distance_to(self, other: Self) -> f32 {
        (self.distance_to_squared(other) as f32).sqrt()
    }

    pub fn distance_to_squared(self, other: Self) -> i32 {
        IVec3::distance_squared(self.into(), other.into())
    }

    pub fn direction_to(self, other: Self) -> Result<Dir3, InvalidDirectionError> {
        Dir3::new((other - self).as_vec3())
    }

    pub fn min(self, rhs: Self) -> Self {
        Self::new(self.x.min(rhs.x), self.y.min(rhs.y), self.z.min(rhs.z))
    }

    pub fn max(self, rhs: Self) -> Self {
        Self::new(self.x.max(rhs.x), self.y.max(rhs.y), self.z.max(rhs.z))
    }
}

impl<T> std::fmt::Display for Pos<T> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "[{}, {}, {}]", self.x, self.y, self.z)
    }
}

impl<T> std::fmt::Debug for Pos<T> {
    fn fmt(&self, fmt: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        fmt.debug_tuple(stringify!(Pos<T>))
            .field(&self.x)
            .field(&self.y)
            .field(&self.z)
            .finish()
    }
}

// Trait implementations that SHOULD be handled by #[derive]

use bevy::ecs::component::StorageType;
impl<T: Send + Sync + 'static> Component for Pos<T> {
    const STORAGE_TYPE: StorageType = StorageType::Table;
}

impl<T> Default for Pos<T> {
    fn default() -> Self {
        Self {
            x: 0,
            y: 0,
            z: 0,
            _marker: PhantomData,
        }
    }
}

impl<T> Clone for Pos<T> {
    fn clone(&self) -> Self {
        *self
    }
}

impl<T> Copy for Pos<T> {}

impl<T> PartialEq for Pos<T> {
    fn eq(&self, other: &Self) -> bool {
        (self.x, self.y, self.z).eq(&(other.x, other.y, other.z))
    }
}

impl<T> Eq for Pos<T> {}

impl<T> std::hash::Hash for Pos<T> {
    fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
        (self.x, self.y, self.z).hash(state)
    }
}

// Conversion

impl<T> From<(i32, i32, i32)> for Pos<T> {
    fn from((x, y, z): (i32, i32, i32)) -> Self {
        Self::new(x, y, z)
    }
}
impl<T> From<Pos<T>> for (i32, i32, i32) {
    fn from(Pos { x, y, z, .. }: Pos<T>) -> Self {
        (x, y, z)
    }
}

impl<T> From<[i32; 3]> for Pos<T> {
    fn from([x, y, z]: [i32; 3]) -> Self {
        Self::new(x, y, z)
    }
}
impl<T> From<Pos<T>> for [i32; 3] {
    fn from(Pos { x, y, z, .. }: Pos<T>) -> Self {
        [x, y, z]
    }
}

impl<T> From<IVec3> for Pos<T> {
    fn from(IVec3 { x, y, z }: IVec3) -> Self {
        Self::new(x, y, z)
    }
}
impl<T> From<Pos<T>> for IVec3 {
    fn from(Pos { x, y, z, .. }: Pos<T>) -> Self {
        Self::new(x, y, z)
    }
}

// Offsetting

impl<T> Add<IVec3> for Pos<T> {
    type Output = Pos<T>;
    fn add(self, rhs: IVec3) -> Self::Output {
        Self::new(self.x + rhs.x, self.y + rhs.y, self.z + rhs.z)
    }
}

impl<T> Sub<IVec3> for Pos<T> {
    type Output = Pos<T>;
    fn sub(self, rhs: IVec3) -> Self::Output {
        Self::new(self.x - rhs.x, self.y - rhs.y, self.z - rhs.z)
    }
}

impl<T> AddAssign<IVec3> for Pos<T> {
    fn add_assign(&mut self, rhs: IVec3) {
        self.x += rhs.x;
        self.y += rhs.y;
        self.z += rhs.z;
    }
}

impl<T> SubAssign<IVec3> for Pos<T> {
    fn sub_assign(&mut self, rhs: IVec3) {
        self.x -= rhs.x;
        self.y -= rhs.y;
        self.z -= rhs.z;
    }
}

// Difference

impl<T> Sub<Pos<T>> for Pos<T> {
    type Output = IVec3;
    fn sub(self, rhs: Self) -> IVec3 {
        IVec3::new(self.x - rhs.x, self.y - rhs.y, self.z - rhs.z)
    }
}

// Indexing

impl<T> Index<usize> for Pos<T> {
    type Output = i32;
    fn index(&self, index: usize) -> &Self::Output {
        match index {
            0 => &self.x,
            1 => &self.y,
            2 => &self.z,
            _ => panic!("index out of bounds"),
        }
    }
}

impl<T> IndexMut<usize> for Pos<T> {
    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
        match index {
            0 => &mut self.x,
            1 => &mut self.y,
            2 => &mut self.z,
            _ => panic!("index out of bounds"),
        }
    }
}