use bevy::prelude::*;
use bevy_mod_raycast::{RayCastMethod, RayCastSource};

use crate::player::*;

pub struct MyRaycastSet;

pub struct Camera;
pub fn spawn_camera(commands: &mut Commands) {
    commands
        .spawn_bundle(PerspectiveCameraBundle::default())
        .insert(Camera)
        .insert(RayCastSource::<MyRaycastSet>::new());
}

pub fn camera_follow_player(
    player: Query<(&Transform, &Player), Without<Camera>>,
    mut camera: Query<(&mut Transform, &Camera), Without<Player>>,
) {
    let player_pos = if let Some(player) = player.iter().next() {
        player.0.translation
    } else {
        return;
    };

    for (mut trans, _) in camera.iter_mut() {
        trans.translation = player_pos + Vec3::new(-50.0, 100.0, 50.0);
        trans.look_at(player_pos, Vec3::Y);
    }
}

// update our `RayCastSource` with the current cursor position every frame.
pub fn update_raycast_with_cursor(
    mut cursor: EventReader<CursorMoved>,
    mut query: Query<&mut RayCastSource<MyRaycastSet>>,
) {
    for mut pick_source in query.iter_mut() {
        // Grab the most recent cursor event if it exists:
        if let Some(cursor_latest) = cursor.iter().last() {
            pick_source.cast_method = RayCastMethod::Screenspace(cursor_latest.position);
        }
    }
}

#[derive(Default)]
pub struct MouseCoords(pub Vec3);

// Update our `RayCastSource` with the current cursor position every frame.
pub fn update_mouse_coords(
    query: Query<&RayCastSource<MyRaycastSet>>,
    mut coords: ResMut<MouseCoords>,
) {
    for pick_source in query.iter() {
        if let Some((_, intersection)) = pick_source.intersect_top() {
            coords.0 = intersection.position();
        }
    }
}