use std::{
    cmp::{max, min},
    f32::consts::PI,
    fmt::Display,
    marker::PhantomData,
    ops::Sub,
    sync::RwLock,
};

use bevy::{ecs::query::WorldQuery, prelude::*, utils::FloatOrd};
use bevy_rapier2d::{
    parry::query::{closest_points, distance, ClosestPoints},
    prelude::*,
    rapier::{math::Isometry, prelude::AABB},
};
use once_cell::sync::Lazy;
use rand::prelude::*;
use serde::{Deserialize, Serialize};

#[derive(Clone, Copy, Debug, Reflect)]
pub enum Angle {
    Degrees(f32),
    Radians(f32),
}

impl Default for Angle {
    fn default() -> Self {
        Self::Radians(0.)
    }
}

impl Angle {
    pub fn degrees(&self) -> f32 {
        use Angle::*;
        let mut degrees: f32 = match self {
            Degrees(v) => *v,
            Radians(v) => v.to_degrees(),
        };
        while degrees < 0. {
            degrees += 360.;
        }
        while degrees >= 360. {
            degrees %= 360.;
        }
        degrees
    }

    pub fn degrees_u32(&self) -> u32 {
        self.degrees() as u32
    }

    pub fn radians(&self) -> f32 {
        use Angle::*;
        match self {
            Degrees(v) => v.to_radians(),
            Radians(v) => *v,
        }
    }

    fn relative_desc(&self) -> String {
        let mode = RELATIVE_DIRECTION_MODE.read().unwrap();
        match self.degrees() {
            v if v <= 15. => "ahead",
            v if v <= 45. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "11:00"
                } else {
                    "ahead and left"
                }
            }
            v if v <= 75. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "10:00"
                } else {
                    "left and ahead"
                }
            }
            v if v <= 105. => "left",
            v if v <= 135. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "8:00"
                } else {
                    "left and behind"
                }
            }
            v if v <= 165. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "7:00"
                } else {
                    "behind and left"
                }
            }
            v if v <= 195. => "behind",
            v if v <= 225. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "5:00"
                } else {
                    "behind and right"
                }
            }
            v if v <= 255. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "4:00"
                } else {
                    "right and behind"
                }
            }
            v if v <= 285. => "right",
            v if v <= 315. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "2:00"
                } else {
                    "right and ahead"
                }
            }
            v if v <= 345. => {
                if *mode == RelativeDirectionMode::ClockFacing {
                    "1:00"
                } else {
                    "ahead and right"
                }
            }
            _ => "ahead",
        }
        .into()
    }
}

impl Sub for Angle {
    type Output = Self;

    fn sub(self, rhs: Self) -> Self::Output {
        match self {
            Angle::Degrees(v1) => match rhs {
                Angle::Degrees(v2) => Angle::Degrees(v1 - v2),
                Angle::Radians(v2) => Angle::Degrees(v1 - v2.to_degrees()),
            },
            Angle::Radians(v1) => match rhs {
                Angle::Degrees(v2) => Angle::Radians(v1 - v2.to_radians()),
                Angle::Radians(v2) => Angle::Radians(v1 - v2),
            },
        }
    }
}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum MovementDirection {
    North,
    NorthNortheast,
    Northeast,
    EastNortheast,
    East,
    EastSoutheast,
    Southeast,
    SouthSoutheast,
    South,
    SouthSouthwest,
    Southwest,
    WestSouthwest,
    West,
    WestNorthwest,
    Northwest,
    NorthNorthwest,
}

impl From<Angle> for MovementDirection {
    fn from(angle: Angle) -> Self {
        let heading = angle.degrees();
        use MovementDirection::*;
        match heading {
            h if h < 11.5 => East,
            h if h < 34.0 => EastNortheast,
            h if h < 56.5 => Northeast,
            h if h < 79.0 => NorthNortheast,
            h if h < 101.5 => North,
            h if h < 124.0 => NorthNorthwest,
            h if h < 146.5 => Northwest,
            h if h < 169.0 => WestNorthwest,
            h if h < 191.5 => West,
            h if h < 214.0 => WestSouthwest,
            h if h < 236.5 => Southwest,
            h if h < 259.0 => SouthSouthwest,
            h if h < 281.5 => South,
            h if h < 304.0 => SouthSoutheast,
            h if h < 326.5 => Southeast,
            h if h <= 349.0 => EastSoutheast,
            _ => East,
        }
    }
}

// Converting from strings into directions doesn't make sense.
#[allow(clippy::from_over_into)]
impl Into<String> for MovementDirection {
    fn into(self) -> String {
        use MovementDirection::*;
        match self {
            North => "north".to_string(),
            NorthNortheast => "north northeast".to_string(),
            Northeast => "northeast".to_string(),
            EastNortheast => "east northeast".to_string(),
            East => "east".to_string(),
            EastSoutheast => "east southeast".to_string(),
            Southeast => "southeast".to_string(),
            SouthSoutheast => "south southeast".to_string(),
            South => "south".to_string(),
            SouthSouthwest => "south southwest".to_string(),
            Southwest => "southwest".to_string(),
            WestSouthwest => "west southwest".to_string(),
            West => "west".to_string(),
            WestNorthwest => "west northwest".to_string(),
            Northwest => "northwest".to_string(),
            NorthNorthwest => "north northwest".to_string(),
        }
    }
}

impl Display for MovementDirection {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let str: String = (*self).into();
        write!(f, "{}", str)
    }
}

#[derive(Component, Clone, Copy, Debug, Eq, PartialEq)]
pub enum CardinalDirection {
    North,
    East,
    South,
    West,
}

impl From<Angle> for CardinalDirection {
    fn from(angle: Angle) -> Self {
        let heading = angle.degrees();
        use CardinalDirection::*;
        match heading {
            h if h <= 45. => East,
            h if h <= 135. => North,
            h if h <= 225. => West,
            h if h <= 315. => South,
            _ => East,
        }
    }
}

impl From<&CardinalDirection> for Angle {
    fn from(direction: &CardinalDirection) -> Self {
        use CardinalDirection::*;
        match direction {
            North => Angle::Radians(PI / 2.),
            East => Angle::Radians(0.),
            South => Angle::Radians(PI * 1.5),
            West => Angle::Radians(PI),
        }
    }
}

// Converting from strings into directions doesn't make sense.
#[allow(clippy::from_over_into)]
impl Into<String> for CardinalDirection {
    fn into(self) -> String {
        use CardinalDirection::*;
        match self {
            North => "north".to_string(),
            East => "east".to_string(),
            South => "south".to_string(),
            West => "west".to_string(),
        }
    }
}

impl Display for CardinalDirection {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        let str: String = (*self).into();
        write!(f, "{}", str)
    }
}

#[derive(Clone, Copy, Debug, Deserialize, Eq, PartialEq, Serialize)]
pub enum RelativeDirectionMode {
    ClockFacing,
    Directional,
}

static RELATIVE_DIRECTION_MODE: Lazy<RwLock<RelativeDirectionMode>> = Lazy::new(|| {
    let v = RelativeDirectionMode::Directional;
    RwLock::new(v)
});

static PHYSICS_SCALE: Lazy<RwLock<f32>> = Lazy::new(|| RwLock::new(1.));

pub trait PointLike {
    fn x(&self) -> f32;

    fn y(&self) -> f32;

    fn x_i32(&self) -> i32 {
        self.x().trunc() as i32
    }

    fn y_i32(&self) -> i32 {
        self.y().trunc() as i32
    }

    fn x_usize(&self) -> usize {
        self.x().trunc() as usize
    }

    fn y_usize(&self) -> usize {
        self.y().trunc() as usize
    }

    fn f32(&self) -> (f32, f32) {
        (self.x(), self.y())
    }

    fn i32(&self) -> (i32, i32) {
        (self.x_i32(), self.y_i32())
    }

    fn floor(&self) -> (f32, f32) {
        (self.x().floor(), self.y().floor())
    }

    fn to_index(&self, width: usize) -> usize {
        ((self.y_i32() * width as i32) + self.x_i32()) as usize
    }

    fn distance_squared(&self, other: &dyn PointLike) -> f32 {
        let x1 = FloatOrd(self.x());
        let y1 = FloatOrd(self.y());
        let x2 = FloatOrd(other.x());
        let y2 = FloatOrd(other.y());
        let dx = max(x1, x2).0 - min(x1, x2).0;
        let dy = max(y1, y2).0 - min(y1, y2).0;
        (dx * dx) + (dy * dy)
    }

    fn distance(&self, other: &dyn PointLike) -> f32 {
        self.distance_squared(other).sqrt()
    }

    fn bearing(&self, other: &dyn PointLike) -> Angle {
        let y = other.y() - self.y();
        let x = other.x() - self.x();
        Angle::Radians(y.atan2(x))
    }

    fn direction(&self, other: &dyn PointLike) -> MovementDirection {
        self.bearing(other).into()
    }

    fn direction_and_distance(&self, other: &dyn PointLike, yaw: Option<Angle>) -> String {
        let mut tokens: Vec<String> = vec![];
        let distance = self.distance(other).round() as i32;
        if distance > 0 {
            let tile_or_tiles = if distance == 1 { "tile" } else { "tiles" };
            let direction: String = if let Some(yaw) = yaw {
                let bearing = self.bearing(other);
                (bearing - yaw).relative_desc()
            } else {
                self.direction(other).into()
            };
            tokens.push(format!("{direction} {distance} {tile_or_tiles}"));
        }
        tokens.join(" ")
    }
}

impl PointLike for Transform {
    fn x(&self) -> f32 {
        self.translation.x
    }

    fn y(&self) -> f32 {
        self.translation.y
    }
}

impl PointLike for &Transform {
    fn x(&self) -> f32 {
        self.translation.x
    }

    fn y(&self) -> f32 {
        self.translation.y
    }
}

impl PointLike for GlobalTransform {
    fn x(&self) -> f32 {
        self.translation().x
    }

    fn y(&self) -> f32 {
        self.translation().y
    }
}

impl PointLike for &GlobalTransform {
    fn x(&self) -> f32 {
        self.translation().x
    }

    fn y(&self) -> f32 {
        self.translation().y
    }
}

impl PointLike for Vec2 {
    fn x(&self) -> f32 {
        self.x
    }

    fn y(&self) -> f32 {
        self.y
    }
}

impl PointLike for (i32, i32) {
    fn x(&self) -> f32 {
        self.0 as f32
    }

    fn y(&self) -> f32 {
        self.1 as f32
    }
}

impl PointLike for (f32, f32) {
    fn x(&self) -> f32 {
        self.0
    }

    fn y(&self) -> f32 {
        self.1
    }
}

impl PointLike for (usize, usize) {
    fn x(&self) -> f32 {
        self.0 as f32
    }

    fn y(&self) -> f32 {
        self.1 as f32
    }
}

impl PointLike for here_be_dragons::geometry::Point {
    fn x(&self) -> f32 {
        self.x as f32
    }

    fn y(&self) -> f32 {
        self.y as f32
    }
}

#[macro_export]
macro_rules! impl_pointlike_for_tuple_component {
    ($source:ty) => {
        impl PointLike for $source {
            fn x(&self) -> f32 {
                self.0 .0 as f32
            }

            fn y(&self) -> f32 {
                self.0 .1 as f32
            }
        }
    };
}

impl From<&dyn PointLike> for (i32, i32) {
    fn from(val: &dyn PointLike) -> Self {
        val.i32()
    }
}

pub trait TransformExt {
    fn yaw(&self) -> Angle;
}

impl TransformExt for Transform {
    fn yaw(&self) -> Angle {
        let forward = self.right();
        Angle::Radians(forward.y.atan2(forward.x))
    }
}

pub trait GlobalTransformExt {
    fn yaw(&self) -> Angle;

    fn closest_points(
        &self,
        collider: &Collider,
        other: &GlobalTransform,
        other_collider: &Collider,
    ) -> ClosestPoints;

    fn collider_direction_and_distance(
        &self,
        collider: &Collider,
        other: &GlobalTransform,
        other_collider: &Collider,
    ) -> String;
}

impl GlobalTransformExt for GlobalTransform {
    fn yaw(&self) -> Angle {
        let forward = self.right();
        Angle::Radians(forward.y.atan2(forward.x))
    }

    fn closest_points(
        &self,
        collider: &Collider,
        other: &GlobalTransform,
        other_collider: &Collider,
    ) -> ClosestPoints {
        use bevy::math::Vec3Swizzles;
        let scale = PHYSICS_SCALE.read().unwrap();
        let pos1 = Isometry::new(
            (self.translation() / *scale).xy().into(),
            self.yaw().radians(),
        );
        let pos2 = Isometry::new(
            (other.translation() / *scale).xy().into(),
            other.yaw().radians(),
        );
        closest_points(&pos1, &*collider.raw, &pos2, &*other_collider.raw, f32::MAX).unwrap()
    }

    fn collider_direction_and_distance(
        &self,
        collider: &Collider,
        other: &GlobalTransform,
        other_collider: &Collider,
    ) -> String {
        use bevy::math::Vec3Swizzles;
        let scale = PHYSICS_SCALE.read().unwrap();
        let pos1 = Isometry::new(
            (self.translation() / *scale).xy().into(),
            self.yaw().radians(),
        );
        let pos2 = Isometry::new(
            (other.translation() / *scale).xy().into(),
            other.yaw().radians(),
        );
        let closest = self.closest_points(collider, other, other_collider);
        let distance = distance(&pos1, &*collider.raw, &pos2, &*other_collider.raw).unwrap() as u32;
        let tile_or_tiles = if distance == 1 { "tile" } else { "tiles" };
        if distance > 0 {
            if let ClosestPoints::WithinMargin(p1, p2) = closest {
                let p1 = (p1.x, p1.y);
                let p2 = (p2.x, p2.y);
                let bearing = p1.bearing(&p2);
                let yaw = self.yaw();
                let direction = (bearing - yaw).relative_desc();
                format!("{direction} {distance} {tile_or_tiles}")
            } else {
                format!("{} {}", distance, tile_or_tiles)
            }
        } else {
            format!("{} {}", distance, tile_or_tiles)
        }
    }
}

#[derive(Component, Copy, Clone, Debug, Deref, DerefMut, PartialEq)]
pub struct Area(pub AABB);

#[derive(Component, Clone, Copy, Debug, Default, Reflect)]
#[reflect(Component)]
pub struct Player;

#[derive(Clone, Copy, Debug)]
pub struct Pool<T> {
    pub value: T,
    pub max: T,
}

impl<T> Default for Pool<T>
where
    T: Default,
{
    fn default() -> Self {
        Self {
            value: Default::default(),
            max: Default::default(),
        }
    }
}

#[derive(Clone, Debug)]
pub struct RandomTable<T>(Vec<T>)
where
    T: Clone;

impl<T> RandomTable<T>
where
    T: Clone,
{
    pub fn add(&mut self, value: T, weight: i32) -> &mut Self {
        if weight > 0 {
            for _ in 0..weight {
                self.0.push(value.clone());
            }
        }
        self
    }
}

impl<T> Default for RandomTable<T>
where
    T: Clone,
{
    fn default() -> Self {
        Self(vec![])
    }
}

impl<T> Iterator for RandomTable<T>
where
    T: Clone,
{
    type Item = T;

    fn next(&mut self) -> Option<Self::Item> {
        let mut rng = thread_rng();
        self.0.shuffle(&mut rng);
        self.0.get(0).cloned()
    }
}

fn setup(core_config: Res<CoreConfig>) {
    let mut scale = PHYSICS_SCALE.write().unwrap();
    *scale = core_config.pixels_per_unit as f32;
    let mut mode = RELATIVE_DIRECTION_MODE.write().unwrap();
    *mode = core_config.relative_direction_mode;
}

#[derive(Clone, Copy, Debug)]
pub struct CoreConfig {
    pub relative_direction_mode: RelativeDirectionMode,
    pub pixels_per_unit: u8,
}

impl Default for CoreConfig {
    fn default() -> Self {
        Self {
            relative_direction_mode: RelativeDirectionMode::Directional,
            pixels_per_unit: 1,
        }
    }
}

fn sync_config(config: Res<CoreConfig>) {
    if config.is_changed() {
        let mut mode = RELATIVE_DIRECTION_MODE.write().unwrap();
        *mode = config.relative_direction_mode;
    }
}

pub struct CorePlugin<RapierUserData>(PhantomData<RapierUserData>);

impl<RapierUserData> Default for CorePlugin<RapierUserData> {
    fn default() -> Self {
        Self(PhantomData)
    }
}

impl<RapierUserData: 'static + WorldQuery + Send + Sync> Plugin for CorePlugin<RapierUserData> {
    fn build(&self, app: &mut App) {
        if !app.world.contains_resource::<CoreConfig>() {
            app.insert_resource(CoreConfig::default());
        }
        let config = *app.world.get_resource::<CoreConfig>().unwrap();
        app.add_plugin(RapierPhysicsPlugin::<RapierUserData>::pixels_per_meter(
            config.pixels_per_unit as f32,
        ))
        .add_startup_system(setup)
        .add_system(sync_config);
    }
}

pub struct CorePlugins<RapierUserData>(PhantomData<RapierUserData>);

impl<RapierUserData> Default for CorePlugins<RapierUserData> {
    fn default() -> Self {
        Self(PhantomData)
    }
}

impl<RapierUserData: 'static + WorldQuery + Send + Sync> PluginGroup
    for CorePlugins<RapierUserData>
{
    fn build(&mut self, group: &mut bevy::app::PluginGroupBuilder) {
        group
            .add(crate::bevy_tts::TtsPlugin)
            .add(crate::bevy_synthizer::SynthizerPlugin)
            .add(CorePlugin::<RapierUserData>::default());
    }
}