// TODO:
// * Determine where local assets folder needs to be created
// * Create local assets folder
// * Recusrively laod that folder and watch for changes
// * Copy assets into local folder in leue of importing them
// * Check portability by moving binary + folder to new location

use std::{
    fs::{DirBuilder, File},
    io::Write,
    time::Duration,
};

use bevy::{
    asset::{Asset, ChangeWatcher},
    audio::PlaybackMode,
    gltf::Gltf,
    prelude::*,
    tasks::IoTaskPool,
};
use monologue_trees::{debug::*, ui};

fn main() {
    App::new()
        .init_resource::<AssetRegistry>()
        .add_plugins((
            DefaultPlugins
                .set(WindowPlugin {
                    primary_window: Some(Window {
                        title: "Serialization WTF".into(),
                        resolution: (640., 480.).into(),
                        ..default()
                    }),
                    ..default()
                })
                .set(AssetPlugin {
                    asset_folder: "assets".into(),
                    // Tell the asset server to watch for asset changes on disk:
                    watch_for_changes: ChangeWatcher::with_delay(Duration::from_millis(0)),
                    ..default()
                }),
            DebugInfoPlugin,
            ui::GameUiPlugin { ..default() },
        ))
        .add_systems(Startup, (init, init_assets_dir))
        .add_systems(
            Update,
            (
                export.run_if(interaction_condition::<ExportAction>),
                clear.run_if(interaction_condition::<ClearAction>),
                import.run_if(interaction_condition::<ImportAction>),
                inspect.run_if(interaction_condition::<InspectAction>),
                load.run_if(interaction_condition::<LoadAssetsAction>),
                unload.run_if(interaction_condition::<UnloadAssetsAction>),
                spawn_level.run_if(interaction_condition::<SpawnLevelAction>),
                asset_inspector::<AudioSource>,
                asset_inspector::<Scene>,
            ),
        )
        .add_systems(
            PostUpdate,
            (
                rehydrate::<Visibility, ComputedVisibility>,
                rehydrate::<Handle<AudioSource>, PlaybackSettings>,
                fallback_camera.run_if(fallback_camera_condition),
            ),
        )
        .run();
}

#[derive(Debug, Component, Reflect, Default)]
#[reflect(Component)]
struct LevelRoot;

#[derive(Debug, Component)]
struct ExportAction;

#[derive(Debug, Component)]
struct ClearAction;

#[derive(Debug, Component)]
struct ImportAction;

#[derive(Debug, Component)]
struct InspectAction;

#[derive(Debug, Component)]
struct LoadAssetsAction;

#[derive(Debug, Component)]
struct UnloadAssetsAction;

#[derive(Debug, Component)]
struct SpawnLevelAction;

#[derive(Debug, Resource, Default)]
struct AssetRegistry {
    handles: Vec<HandleUntyped>,
}

fn init_assets_dir() {
    IoTaskPool::get()
        .spawn(async move {
            match DirBuilder::new().create("assets") {
                Ok(_) => info!("Created assets directory"),
                Err(e) => warn!("Error creating assets directory", e),
            }
        })
        .detach();
}

fn init(mut commands: Commands) {
    commands.spawn((
        Camera2dBundle { ..default() },
        UiCameraConfig { show_ui: true },
    ));

    commands
        .spawn((
            NodeBundle {
                style: Style {
                    top: Val::Px(0.0),
                    right: Val::Px(0.0),
                    margin: UiRect::all(Val::Px(5.0)),
                    padding: UiRect::all(Val::Px(5.0)),
                    border: UiRect::all(Val::Px(1.0)),
                    position_type: PositionType::Absolute,
                    ..default()
                },
                background_color: Color::WHITE.into(),
                border_color: Color::BLACK.into(),
                ..default()
            },
            ui::Select::Action,
        ))
        .with_children(|parent| {
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Load Assets".into(),
                    ..default()
                },
                LoadAssetsAction,
            ));
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Dump Assets".into(),
                    ..default()
                },
                UnloadAssetsAction,
            ));
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Spawn Level".into(),
                    ..default()
                },
                SpawnLevelAction,
            ));
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Export".into(),
                    ..default()
                },
                ExportAction,
            ));
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Clear".into(),
                    ..default()
                },
                ClearAction,
            ));
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Import".into(),
                    ..default()
                },
                ImportAction,
            ));
            parent.spawn((
                ButtonBundle {
                    style: Style {
                        margin: UiRect::all(Val::Px(5.0)),
                        padding: UiRect::all(Val::Px(5.0)),
                        border: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Inspect".into(),
                    ..default()
                },
                InspectAction,
            ));
        });
}

fn interaction_condition<T: Component>(
    events: Query<&Interaction, (Changed<Interaction>, With<T>)>,
) -> bool {
    events
        .iter()
        .find(|&interaction| *interaction == Interaction::Pressed)
        .is_some()
}

fn rehydrate<W: Component, WO: Component + Default + std::fmt::Debug>(
    events: Query<Entity, (Added<W>, Without<WO>)>,
    mut commands: Commands,
) {
    events.iter().for_each(|entity| {
        info!("Rehydrating {:?}", WO::default());
        commands.entity(entity).insert(WO::default());
    });
}

fn ser(
    root: &Query<Entity, With<LevelRoot>>,
    children: &Query<&Children>,
    world: &World,
) -> String {
    let app_type_registry = world.resource::<AppTypeRegistry>().clone();
    let mut builder = DynamicSceneBuilder::from_world(world.clone());

    builder.deny_all_resources();

    // builder.allow_all();
    builder.deny::<ComputedVisibility>();

    // Level administrivia
    builder.allow::<LevelRoot>();

    // Scene components
    builder.allow::<Handle<Scene>>();
    builder.allow::<Visibility>();
    builder.allow::<Transform>();
    builder.allow::<GlobalTransform>();

    // Audio components
    builder.allow::<Handle<AudioSource>>();
    builder.allow::<PlaybackSettings>();

    root.iter().for_each(|r| {
        // Extract the level root
        builder.extract_entity(r);

        // Extract all level root children
        builder.extract_entities(
            children
                .get(r)
                .expect("Root has children")
                .iter()
                .map(|&entity| entity),
        );
    });

    let scene = builder.build();

    scene
        .serialize_ron(&app_type_registry)
        .expect("Serialize scene")
}

fn export(root: Query<Entity, With<LevelRoot>>, children: Query<&Children>, world: &World) {
    info!("Export level");

    let serialized = ser(&root, &children, world);

    IoTaskPool::get()
        .spawn(async move {
            // Write the scene RON data to file
            File::create(format!("assets/output.scn.ron"))
                .and_then(|mut file| file.write(serialized.as_bytes()))
                .expect("Error while writing scene to file");
        })
        .detach();
}

fn inspect(root: Query<Entity, With<LevelRoot>>, children: Query<&Children>, world: &World) {
    info!("Inexpect level");

    let serialized = ser(&root, &children, world);

    print!("{}", serialized);
}

fn clear(root: Query<Entity, With<LevelRoot>>, mut commands: Commands) {
    info!("Clearing level");

    root.iter().for_each(|entity| {
        commands.entity(entity).despawn_recursive();
    });
}

// TODO: Figure out how to import the same asset from a differnt source
// How do the plugins do it??
fn import(mut commands: Commands, server: Res<AssetServer>) {
    info!("Importing level");

    let scene_handle: Handle<DynamicScene> = server.load("output.scn.ron");
    commands.spawn((
        LevelRoot,
        DynamicSceneBundle {
            scene: scene_handle.clone(),
            ..default()
        },
    ));
}

fn fallback_camera_condition(
    added: Query<Entity, Added<Camera>>,
    mut removed: RemovedComponents<Camera>,
) -> bool {
    added.iter().chain(removed.iter()).count() > 0
}

fn fallback_camera(
    mut ui_camera: Query<&mut Camera, With<Camera2d>>,
    cameras: Query<&mut Camera, Without<Camera2d>>,
) {
    ui_camera.single_mut().is_active = cameras.iter().len() <= 0;
}

fn asset_inspector<T: Asset>(mut events: EventReader<AssetEvent<T>>) {
    events.iter().for_each(|event| match event {
        AssetEvent::Created { handle } => info!("Asset Created  {:?}", handle),
        AssetEvent::Modified { handle } => info!("Asset Modified {:?}", handle),
        AssetEvent::Removed { handle } => info!("Asset Removed {:?}", handle),
    });
}

// OK seems like `load_folder` does not automatically pick up added files
fn load(mut registry: ResMut<AssetRegistry>, server: Res<AssetServer>) {
    info!("Loading assets");

    registry.handles = server.load_folder("./dynamic").unwrap();
    info!("Current files: {:?}", registry.handles);
}

fn unload(mut registry: ResMut<AssetRegistry>, mut gltfs: ResMut<Assets<Gltf>>) {
    info!("Unloading asstes");

    registry.handles.clear();

    // This is required to clear scenes from asset cache
    gltfs.clear();
}

fn spawn_level(mut commands: Commands, server: Res<AssetServer>) {
    commands
        .spawn((SpatialBundle { ..default() }, LevelRoot))
        .with_children(|parent| {
            parent.spawn(AudioSourceBundle {
                source: server.load::<AudioSource, &str>("dynamic/Lake Sound 1.ogg"),
                settings: PlaybackSettings {
                    mode: PlaybackMode::Loop,
                    paused: false,
                    ..default()
                },
            });
            parent.spawn((SceneBundle {
                scene: server.load("dynamic/materials.glb#Scene0"),
                ..default()
            },));
        });
}