use crate::editor::prelude::*;

#[derive(Debug, Default)]
pub struct EditorAnimationPlugin;

impl Plugin for EditorAnimationPlugin {
    fn build(&self, app: &mut App) {
        app.add_event::<ControlAnimation>()
            .add_systems(Update, sync_asset_buttons::<AnimationClip>)
            .add_systems(Update, sync_remove_asset_buttons::<AnimationClip>)
            .add_systems(Update, set_epoch_animations)
            .add_systems(Update, load_epoch_animations)
            .add_systems(Update, init_animations_ui)
            .add_systems(Update, remove_animations_ui)
            .add_systems(Update, add_animations_ui)
            .add_systems(Update, play_all_animations)
            .add_systems(Update, play_animation)
            .add_systems(Update, ui_control_animations)
            .add_systems(Update, ui_active_animation);
    }
}

#[derive(Debug, Component, Default)]
pub struct AnimationWidget;

#[derive(Debug, Component)]
pub struct AnimationPlayAll;

pub fn init_animations_ui(events: Query<Entity, Added<AnimationWidget>>, mut commands: Commands) {
    events.iter().for_each(|entity| {
        commands.entity(entity).with_children(|parent| {
            parent.spawn((
                AnimationPlayAll,
                ButtonBundle {
                    style: Style {
                        border: UiRect::all(Val::Px(1.0)),
                        margin: UiRect::all(Val::Px(1.0)),
                        padding: UiRect::all(Val::Px(1.0)),
                        ..default()
                    },
                    border_color: Color::BLACK.into(),
                    ..default()
                },
                ui::Title {
                    text: "Play All".into(),
                    ..default()
                },
            ));
        });
    })
}

/// When a new scene is loaded, add any newly compatible animations
/// TODO: Add target entity(s) too
pub fn add_animations_ui(
    player_spawned: Query<&Name, Added<AnimationPlayer>>,
    widget: Query<Entity, With<AnimationWidget>>,
    mut commands: Commands,
    gltfs: Res<Assets<Gltf>>,
    clips: Res<Assets<AnimationClip>>,
) {
    player_spawned.iter().for_each(|player_name| {
        gltfs
            .iter()
            .flat_map(|(_, gltf)| gltf.named_animations.iter())
            .filter_map(|(clip_name, handle)| {
                clips.get(&handle).map(|clip| (clip_name, handle, clip))
            })
            .filter(|(_, _, clip)| clip.compatible_with(player_name))
            .for_each(|(clip_name, handle, _)| {
                create_asset_button(
                    &widget,
                    &mut commands,
                    ui::TargetAsset {
                        handle: handle.clone(),
                    },
                    clip_name.clone(),
                    None,
                );
            });
    });
}

// When a scene is de-selected, remove any outdated animation options
pub fn remove_animations_ui(
    mut removed_players: RemovedComponents<Handle<Scene>>,
    current: Query<(Entity, &ui::TargetAsset<AnimationClip>)>,
    clips: Res<Assets<AnimationClip>>,
    targets: Query<(&AnimationPlayer, &Name)>,
    mut commands: Commands,
) {
    // For each removed scene
    removed_players.iter().for_each(|_| {
        // Iterate over the current animation buttons
        current
            .iter()
            .filter(|(_, ui::TargetAsset { handle })| {
                // Check if this clip is compatible with any remaining entities
                // NOTE: We are checking this is *not* compatible with any entities
                clips
                    .get(handle)
                    .map(|clip| !(targets.iter().any(|(_, name)| clip.compatible_with(name))))
                    .unwrap_or(true)
            })
            .for_each(|(_, ui::TargetAsset { handle })| {
                // Destroy the buton if it is so
                destroy_asset_button(
                    &current,
                    &mut commands,
                    &ui::TargetAsset {
                        handle: handle.clone(),
                    },
                );
            });
    });
}

#[derive(Debug, Event)]
pub enum ControlAnimation {
    Play(Handle<AnimationClip>),
    Pause(Handle<AnimationClip>),
}

pub fn play_animation(
    mut events: EventReader<ControlAnimation>,
    mut targets: Query<(&mut AnimationPlayer, &Name), With<Transform>>,
    clips: Res<Assets<AnimationClip>>,
) {
    events.iter().for_each(|event| match event {
        ControlAnimation::Play(handle) => {
            let clip = clips.get(&handle).expect("Load animation clip");
            targets
                .iter_mut()
                .filter(|(_, name)| clip.compatible_with(name))
                .for_each(|(mut player, _)| {
                    if player.is_paused() {
                        player.resume();
                    } else {
                        player.play(handle.clone()).repeat();
                    }
                });
        }
        ControlAnimation::Pause(handle) => {
            let clip = clips.get(handle).expect("Load animation clip");
            targets
                .iter_mut()
                .filter(|(_, name)| clip.compatible_with(name))
                .for_each(|(mut player, _)| {
                    player.pause();
                });
        }
    });
}

pub fn play_all_animations(
    events: Query<
        (Entity, &Interaction, Option<&ui::Active>),
        (With<AnimationPlayAll>, Changed<Interaction>),
    >,
    clip_btns: Query<&ui::TargetAsset<AnimationClip>>,
    mut writer: EventWriter<ControlAnimation>,
    mut commands: Commands,
) {
    events
        .iter()
        .filter_map(|(entity, &interaction, active)| {
            (interaction == Interaction::Pressed).then_some((entity, active))
        })
        .for_each(|(entity, active)| match active {
            Some(_) => {
                commands.entity(entity).remove::<ui::Active>();
                clip_btns.iter().for_each(|ui::TargetAsset { handle }| {
                    writer.send(ControlAnimation::Pause(handle.clone()));
                });
            }
            None => {
                commands.entity(entity).insert(ui::Active);
                clip_btns.iter().for_each(|ui::TargetAsset { handle }| {
                    writer.send(ControlAnimation::Play(handle.clone()));
                });
            }
        })
}

fn ui_control_animations(
    events: Query<
        (
            &Interaction,
            &ui::TargetAsset<AnimationClip>,
            Option<&ui::Active>,
        ),
        (With<Button>, Changed<Interaction>),
    >,
    mut writer: EventWriter<ControlAnimation>,
) {
    events
        .iter()
        .filter_map(
            |(interaction, ui::TargetAsset { handle }, active)| match interaction {
                Interaction::Pressed => Some((handle, active)),
                _ => None,
            },
        )
        .for_each(|(handle, active)| match active {
            Some(_) => writer.send(ControlAnimation::Pause(handle.clone())),
            None => writer.send(ControlAnimation::Play(handle.clone())),
        });
}

pub fn ui_active_animation(
    mut events: EventReader<ControlAnimation>,
    targets: Query<(Entity, &ui::TargetAsset<AnimationClip>)>,
    mut commands: Commands,
) {
    events.iter().for_each(|event| match event {
        ControlAnimation::Play(this_handle) => {
            targets
                .iter()
                .find_map(|(entity, ui::TargetAsset { handle })| {
                    (handle == this_handle).then_some(entity)
                })
                .into_iter()
                .for_each(|entity| {
                    commands.entity(entity).insert(ui::Active);
                });
        }
        ControlAnimation::Pause(this_handle) => {
            targets
                .iter()
                .find_map(|(entity, ui::TargetAsset { handle })| {
                    (handle == this_handle).then_some(entity)
                })
                .into_iter()
                .for_each(|entity| {
                    commands.entity(entity).remove::<ui::Active>();
                });
        }
    });
}