use bevy::input::mouse::MouseMotion;
use bevy::prelude::*;
use bevy::window::{CursorGrabMode, CursorOptions, PrimaryWindow};
use bevy_kira_audio::{SpatialRadius, prelude::*};

/// This example demonstrates the basic spatial audio support in `bevy_kira_audio`.
/// It adds `SpatialAudioPlugin` then spawns entities with `SpatialAudioEmitter`
/// and a receiver with the `SpatialAudioReceiver` component.
fn main() {
    App::new()
        .add_plugins((
            DefaultPlugins,
            AudioPlugin,
            SpatialAudioPlugin,
            CameraPlugin,
        ))
        .add_systems(Startup, setup)
        .run();
}

fn setup(
    mut commands: Commands,
    asset_server: Res<AssetServer>,
    audio: Res<Audio>,
    mut meshes: ResMut<Assets<Mesh>>,
    mut materials: ResMut<Assets<StandardMaterial>>,
) {
    // Emitter Nr. 1
    let cooking = audio
        .play(asset_server.load("sounds/cooking.ogg"))
        .looped()
        .handle();
    commands.spawn((
        WorldAssetRoot(asset_server.load("models/panStew.glb#Scene0")),
        Transform::from_xyz(-5.0, 0., 0.),
        SpatialAudioEmitter {
            instances: vec![cooking],
        },
        // at a distance of more than 10, we will not hear this emitter anymore
        SpatialRadius { radius: 10.0 },
    ));
    // Emitter Nr. 2
    let elevator_music = audio
        .play(asset_server.load("sounds/loop.ogg"))
        .looped()
        .handle();
    commands.spawn((
        WorldAssetRoot(asset_server.load("models/boxOpen.glb#Scene0")),
        Transform::from_xyz(10., 0., 0.),
        SpatialAudioEmitter {
            instances: vec![elevator_music],
        },
    ));
    // If an emitter has no SpatialRadius, the resource DefaultSpatialRadius is used instead.
    // It defaults to a spatial radius of 25.
    // Our camera will be the receiver.
    commands
        .spawn((Camera3d::default(), Transform::from_xyz(0.0, 0.5, 10.0)))
        .insert(SpatialAudioReceiver)
        .insert(FlyCam);

    // Other scene setup...
    commands.spawn((
        PointLight {
            intensity: 1500.0,
            shadow_maps_enabled: true,
            ..default()
        },
        Transform::from_xyz(4.0, 8.0, 4.0),
    ));
    commands.spawn( (Text::new("WASD to move horizontally\nSPACE to ascend\nLSHIFT to descend\nESC to grab/release cursor."), TextFont{
        font:asset_server.load("fonts/monogram.ttf").into(),
        font_size: 40.0.into(),
        ..default()
    }, TextColor(Color::linear_rgb(0.9, 0.9, 0.9)),
                    Node {margin: UiRect::all(Val::Px(15.)), ..default()}));
    commands.spawn((
        Mesh3d(meshes.add(Cuboid {
            half_size: Vec3::new(25., 0., 25.),
        })),
        MeshMaterial3d(materials.add(StandardMaterial::from_color(LinearRgba::GREEN))),
    ));
}

// only camera handling code from here on...

// Code modified from https://github.com/sburris0/bevy_flycam under the ISC License

// Copyright 2020 Spencer Burris
//
// Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
struct CameraPlugin;

const SENSITIVITY: f32 = 0.00012;
const SPEED: f32 = 12.;

#[derive(Component)]
pub struct FlyCam;

impl Plugin for CameraPlugin {
    fn build(&self, app: &mut App) {
        app.init_resource::<InputState>()
            .add_systems(Startup, initial_grab_cursor)
            .add_systems(Update, (player_move, player_look, cursor_grab));
    }
}

fn initial_grab_cursor(
    mut primary_cursor_options: Single<&mut CursorOptions, With<PrimaryWindow>>,
) {
    toggle_grab_cursor(&mut primary_cursor_options);
}

fn cursor_grab(
    keys: Res<ButtonInput<KeyCode>>,
    mut primary_cursor_options: Single<&mut CursorOptions, With<PrimaryWindow>>,
) {
    if keys.just_pressed(KeyCode::Escape) {
        toggle_grab_cursor(&mut primary_cursor_options);
    }
}

/// Grabs/ungrabs mouse cursor
fn toggle_grab_cursor(cursor_options: &mut CursorOptions) {
    match cursor_options.grab_mode {
        CursorGrabMode::None => {
            cursor_options.grab_mode = CursorGrabMode::Confined;
            cursor_options.visible = false;
        }
        _ => {
            cursor_options.grab_mode = CursorGrabMode::None;
            cursor_options.visible = true;
        }
    }
}

/// Handles keyboard input and movement
fn player_move(
    keys: Res<ButtonInput<KeyCode>>,
    time: Res<Time>,
    primary_cursor_options: Single<&mut CursorOptions, With<PrimaryWindow>>,
    mut query: Query<&mut Transform, With<FlyCam>>,
) {
    for mut transform in query.iter_mut() {
        let mut velocity = Vec3::ZERO;
        let local_z = transform.local_z();
        let forward = -Vec3::new(local_z.x, 0., local_z.z);
        let right = Vec3::new(local_z.z, 0., -local_z.x);

        for key in keys.get_pressed() {
            match primary_cursor_options.grab_mode {
                CursorGrabMode::None => (),
                _ => match key {
                    KeyCode::KeyW => velocity += forward,
                    KeyCode::KeyS => velocity -= forward,
                    KeyCode::KeyA => velocity -= right,
                    KeyCode::KeyD => velocity += right,
                    KeyCode::Space => velocity += Vec3::Y,
                    KeyCode::ShiftLeft => velocity -= Vec3::Y,
                    _ => (),
                },
            }
        }

        velocity = velocity.normalize_or_zero();

        transform.translation += velocity * time.delta_secs() * SPEED;
    }
}

#[derive(Resource, Default)]
struct InputState {
    pitch: f32,
    yaw: f32,
}

/// Handles looking around if cursor is locked
fn player_look(
    primary_cursor_options: Single<&mut CursorOptions, With<PrimaryWindow>>,
    primary_window: Single<&Window, With<PrimaryWindow>>,
    mut state: ResMut<InputState>,
    mut motion: MessageReader<MouseMotion>,
    mut query: Query<&mut Transform, With<FlyCam>>,
) {
    let delta_state = state.as_mut();
    for mut transform in query.iter_mut() {
        for ev in motion.read() {
            match primary_cursor_options.grab_mode {
                CursorGrabMode::None => (),
                _ => {
                    // Using smallest of height or width ensures equal vertical and horizontal sensitivity
                    let window_scale = primary_window.height().min(primary_window.width());
                    delta_state.pitch -= (SENSITIVITY * ev.delta.y * window_scale).to_radians();
                    delta_state.yaw -= (SENSITIVITY * ev.delta.x * window_scale).to_radians();
                }
            }

            delta_state.pitch = delta_state.pitch.clamp(-1.54, 1.54);

            // Order is important to prevent unintended roll
            transform.rotation = Quat::from_axis_angle(Vec3::Y, delta_state.yaw)
                * Quat::from_axis_angle(Vec3::X, delta_state.pitch);
        }
    }
}