use bevy::{
    app::{App, Startup, Update},
    asset::{AssetEvent, AssetServer, Assets},
    ecs::{
        event::EventReader,
        query::{With, Without},
        system::{Commands, Query, Res, Single},
    },
    image::Image,
    math::{Vec2, Vec3},
    sprite::{Sprite, SpriteImageMode},
    transform::components::Transform,
    window::{Window, WindowResized},
};

use crate::{
    client::Me,
    ecs::{MainCamera, StarfieldBack, StarfieldFront, StarfieldMid},
};

pub const BACK_STARFIELD_SIZE: f32 = 256.0;
pub const MID_STARFIELD_SIZE: f32 = 384.0;
pub const FRONT_STARFIELD_SIZE: f32 = 512.0;

pub fn starfield_plugin(app: &mut App) {
    app.add_systems(Startup, setup_starfield)
        .add_systems(Update, fix_starfield)
        .add_systems(Update, resize_starfield)
        .add_systems(Update, update_starfield);
}

pub fn setup_starfield(
    mut commands: Commands,
    asset_server: Res<AssetServer>,
    window: Query<&Window>,
) {
    let starfield_handle = asset_server.load("textures/starfield.png");
    let starfield_transp_handle = asset_server.load("textures/starfield_transp.png");
    let window = window.iter().next().unwrap();
    commands
        .spawn(Sprite {
            image: starfield_handle,
            custom_size: Some(window.size() + Vec2::splat(BACK_STARFIELD_SIZE)),
            image_mode: SpriteImageMode::Tiled {
                tile_x: true,
                tile_y: true,
                stretch_value: 1.0,
            },
            ..Default::default()
        })
        .insert(Transform::from_xyz(0.0, 0.0, 5.0))
        .insert(StarfieldBack);
    commands
        .spawn(Sprite {
            image: starfield_transp_handle.clone(),
            custom_size: Some(window.size() + Vec2::splat(MID_STARFIELD_SIZE)),
            image_mode: SpriteImageMode::Tiled {
                tile_x: true,
                tile_y: true,
                stretch_value: 1.0,
            },
            ..Default::default()
        })
        .insert(Transform::from_xyz(0.0, 0.0, 4.5))
        .insert(StarfieldMid);
    commands
        .spawn(Sprite {
            image: starfield_transp_handle,
            custom_size: Some(window.size() + Vec2::splat(FRONT_STARFIELD_SIZE)),
            image_mode: SpriteImageMode::Tiled {
                tile_x: true,
                tile_y: true,
                stretch_value: 1.0,
            },
            ..Default::default()
        })
        .insert(Transform::from_xyz(0.0, 0.0, 4.0))
        .insert(StarfieldFront);
}

pub fn fix_starfield(
    mut starfield_back: Query<
        &mut Sprite,
        (
            With<StarfieldBack>,
            Without<StarfieldMid>,
            Without<StarfieldFront>,
        ),
    >,
    mut starfield_mid: Query<
        &mut Sprite,
        (
            With<StarfieldMid>,
            Without<StarfieldBack>,
            Without<StarfieldFront>,
        ),
    >,
    mut starfield_front: Query<
        &mut Sprite,
        (
            With<StarfieldFront>,
            Without<StarfieldBack>,
            Without<StarfieldMid>,
        ),
    >,
    assets: Res<Assets<Image>>,
    mut asset_events: EventReader<AssetEvent<Image>>,
) {
    for event in asset_events.read() {
        if let AssetEvent::Added { id } = event {
            let mut starfield_back = starfield_back.single_mut().unwrap();
            if *id == starfield_back.image.id() {
                let starfield_image = assets.get(*id).unwrap();
                starfield_back.image_mode = SpriteImageMode::Tiled {
                    tile_x: true,
                    tile_y: true,
                    stretch_value: BACK_STARFIELD_SIZE / (starfield_image.size().x as f32),
                };
            }
            let mut starfield_mid = starfield_mid.single_mut().unwrap();
            if *id == starfield_mid.image.id() {
                let starfield_image = assets.get(*id).unwrap();
                starfield_mid.image_mode = SpriteImageMode::Tiled {
                    tile_x: true,
                    tile_y: true,
                    stretch_value: MID_STARFIELD_SIZE / (starfield_image.size().x as f32),
                };
            }
            let mut starfield_front = starfield_front.single_mut().unwrap();
            if *id == starfield_front.image.id() {
                let starfield_image = assets.get(*id).unwrap();
                starfield_front.image_mode = SpriteImageMode::Tiled {
                    tile_x: true,
                    tile_y: true,
                    stretch_value: FRONT_STARFIELD_SIZE / (starfield_image.size().x as f32),
                };
            }
        }
    }
}

pub fn resize_starfield(
    mut starfield_back: Query<
        &mut Sprite,
        (
            With<StarfieldBack>,
            Without<StarfieldMid>,
            Without<StarfieldFront>,
        ),
    >,
    mut starfield_mid: Query<
        &mut Sprite,
        (
            With<StarfieldMid>,
            Without<StarfieldBack>,
            Without<StarfieldFront>,
        ),
    >,
    mut starfield_front: Query<
        &mut Sprite,
        (
            With<StarfieldFront>,
            Without<StarfieldBack>,
            Without<StarfieldMid>,
        ),
    >,
    mut resize_event: EventReader<WindowResized>,
    camera: Single<&Transform, With<MainCamera>>,
) {
    for event in resize_event.read() {
        starfield_back.single_mut().unwrap().custom_size =
            Some(Vec2::new(event.width, event.height) * camera.scale.z + Vec2::splat(BACK_STARFIELD_SIZE * 2.0));
        starfield_mid.single_mut().unwrap().custom_size =
            Some(Vec2::new(event.width, event.height) * camera.scale.z + Vec2::splat(MID_STARFIELD_SIZE * 2.0));
        starfield_front.single_mut().unwrap().custom_size =
            Some(Vec2::new(event.width, event.height) * camera.scale.z + Vec2::splat(FRONT_STARFIELD_SIZE * 2.0));
    }
}

pub fn update_starfield(
    mut starfield_back: Query<
        &mut Transform,
        (
            With<StarfieldBack>,
            Without<Me>,
            Without<StarfieldMid>,
            Without<StarfieldFront>,
        ),
    >,
    mut starfield_mid: Query<
        &mut Transform,
        (
            With<StarfieldMid>,
            Without<Me>,
            Without<StarfieldBack>,
            Without<StarfieldFront>,
        ),
    >,
    mut starfield_front: Query<
        &mut Transform,
        (
            With<StarfieldFront>,
            Without<Me>,
            Without<StarfieldBack>,
            Without<StarfieldMid>,
        ),
    >,
    window: Single<&Window>,
    camera: Single<&Transform, (With<MainCamera>, Without<Me>, Without<StarfieldFront>, Without<StarfieldMid>, Without<StarfieldBack>)>,
    player: Query<&Transform, (With<Me>, Without<StarfieldFront>)>,
) {
    let Some(player) = player.iter().next() else {
        return;
    };
    let mut starfield_back_pos = starfield_back.single_mut().unwrap();
    let mut starfield_mid_pos = starfield_mid.single_mut().unwrap();
    let mut starfield_front_pos = starfield_front.single_mut().unwrap();
    //starfield_pos.translation = (player.translation / STARFIELD_SIZE).round() * STARFIELD_SIZE;
    starfield_back_pos.translation = player.translation
        + (-player.translation / 3.0) % BACK_STARFIELD_SIZE
        + (Vec3::new(window.resolution.width(), -window.resolution.height(), 0.0)*camera.scale.z/2.0) % BACK_STARFIELD_SIZE
        + Vec3::new(0.0, BACK_STARFIELD_SIZE, 0.0)
        - Vec3::new(0.0, 0.0, 5.0);
    starfield_mid_pos.translation = player.translation
        + (-player.translation / 2.5) % MID_STARFIELD_SIZE
        + (Vec3::new(window.resolution.width(), -window.resolution.height(), 0.0)*camera.scale.z/2.0) % MID_STARFIELD_SIZE
        + Vec3::new(0.0, MID_STARFIELD_SIZE, 0.0)
        - Vec3::new(0.0, 0.0, 4.5);
    starfield_front_pos.translation = player.translation
        + (-player.translation / 2.0) % FRONT_STARFIELD_SIZE
        + (Vec3::new(window.resolution.width(), -window.resolution.height(), 0.0)*camera.scale.z/2.0) % FRONT_STARFIELD_SIZE
        + Vec3::new(0.0, FRONT_STARFIELD_SIZE, 0.0)
        - Vec3::new(0.0, 0.0, 4.0);
}