use bevy::prelude::*;
use crate::{nature, settings, actor, audio, hud};

const MIN_INTERACT_DISTANCE: f32 = 30.0;
const ASSET_CONVERSATIONS: &str = "scenes/conversations.scn.ron";

pub struct ActorPlugin;
impl Plugin for ActorPlugin {
    fn build(&self, app: &mut App) {
        app.add_systems(Startup, setup);
        app.register_type::<ChatBranch>();
        app.register_type::<ChatChoice>();
        app.add_systems(FixedUpdate, update);
        app.add_systems(Update, (
            handle_new_conversations,
            handle_conversations,
            handle_input,
        ));
        app.add_event::<StartConversationEvent>();
    }
}

#[derive(Event)]
pub struct StartConversationEvent {
    pub conv: String
}

#[derive(Component)]
pub struct Actor {
    pub hp: f32,
    pub m: f32, // mass
    pub v: Vec3, // velocity
    // TODO: rotation
}

impl Default for Actor {
    fn default() -> Self {
        Self {
            hp: 100.0,
            m: 100.0,
            v: Vec3::ZERO,
        }
    }
}

#[derive(Component)] pub struct Player;
#[derive(Component)] pub struct PlayerInConversation;
#[derive(Component)] pub struct InConversationWithPlayer;

#[derive(Component, Reflect, Default)]
#[reflect(Component)]
pub struct ChatBranch {
    pub id: String,
    pub name: String,
    pub label: String,
    pub delay: f64,
    pub sound: String,
    pub reply: String,
    pub goto: String,
}

#[derive(Component, Reflect, Default)]
#[reflect(Component)]
pub struct ChatChoice {
    pub id: String,
    pub label: String,
    pub choice: String,
    pub goto: String,
}

#[derive(Component)]
pub struct Chat {
    pub id: String,
    pub label: String,
    pub timer: f64,
}

#[derive(Component)]
pub struct Talker {
    pub conv: String,
}

#[derive(Component)]
pub struct LifeForm {
    pub adrenaline: f32,
    pub adrenaline_baseline: f32,
    pub adrenaline_jolt: f32,
}
impl Default for LifeForm { fn default() -> Self { Self {
    adrenaline: 0.3,
    adrenaline_baseline: 0.3,
    adrenaline_jolt: 0.0,
}}}

#[derive(Component)]
pub struct Suit {
    pub oxygen: f32,
    pub power: f32,
    pub oxygen_max: f32,
    pub power_max: f32,
}
impl Default for Suit { fn default() -> Self { SUIT_SIMPLE } }

const SUIT_SIMPLE: Suit = Suit {
    power: 1e5,
    power_max: 1e5,
    oxygen: nature::OXY_D,
    oxygen_max: nature::OXY_D,
};

pub fn setup(
    mut commands: Commands,
    asset_server: Res<AssetServer>,
) {
    commands.spawn(DynamicSceneBundle {
        scene: asset_server.load(ASSET_CONVERSATIONS),
        ..default()
    });
}

//#[allow(dead_code)]
//pub fn serialize(
//    world: &mut World,
//) {
//    let mut scene_world = World::new();
//    scene_world.spawn(ChatBranch {
//        id: "hialien".to_string(),
//        name: "Icarus".to_string(),
//        label: "INTERACT".to_string(),
//        delay: 0.0,
//        reply: "Requesting permission to communicate...".to_string(),
//        goto: "requested".to_string(),
//    });
//    let type_registry = world.resource::<AppTypeRegistry>().clone();
//    scene_world.insert_resource(type_registry);
//    let type_registry = world.resource::<AppTypeRegistry>();
//    let scene = DynamicScene::from_world(&scene_world);
//    let serialized_scene = scene.serialize_ron(type_registry).unwrap();
//    info!("{}", serialized_scene);
//}

pub fn update(
    time: Res<Time>,
    mut query: Query<(&mut LifeForm, &mut Suit)>,
) {
    let d = time.delta_seconds();
    for (mut lifeform, mut suit) in query.iter_mut() {
        if lifeform.adrenaline_jolt.abs() > 1e-3 {
            lifeform.adrenaline_jolt *= 0.99;
        }
        else {
            lifeform.adrenaline_jolt = 0.0
        }
        lifeform.adrenaline = (lifeform.adrenaline - 0.0001 + lifeform.adrenaline_jolt * 0.01).clamp(0.0, 1.0);
        suit.oxygen = (suit.oxygen - nature::OXY_S*d).clamp(0.0, 1.0);
    }
}

pub fn handle_input(
    keyboard_input: Res<ButtonInput<KeyCode>>,
    settings: ResMut<settings::Settings>,
    query: Query<(&Talker, &Transform)>,
    player: Query<&Transform, With<actor::Player>>,
    mut ew_conv: EventWriter<StartConversationEvent>,
    mut ew_sfx: EventWriter<audio::PlaySfxEvent>,
)
{
    if keyboard_input.just_pressed(settings.key_interact) {
        let mindist = MIN_INTERACT_DISTANCE * MIN_INTERACT_DISTANCE;
        if let Ok(player) = player.get_single() {
            for (talker, transform) in &query {
                if transform.translation.distance_squared(player.translation) <= mindist {
                    ew_conv.send(StartConversationEvent{conv: talker.conv.clone()});
                    ew_sfx.send(audio::PlaySfxEvent(audio::Sfx::Ping));
                    break;
                }
            }
        }
    }
}

pub fn handle_new_conversations(
    mut commands: Commands,
    mut er_conv: EventReader<StartConversationEvent>,
    time: Res<Time>,
) {
    for _my_event in er_conv.read() {
        commands.spawn(Chat {
            id: "hialien".to_string(),
            label: "INIT".to_string(),
            timer: time.elapsed_seconds_f64(),
        });
        break;
    }
}

pub fn handle_conversations(
    mut commands: Commands,
    mut log: ResMut<hud::Log>,
    mut q_conv: Query<(Entity, &mut Chat)>,
    mut ew_sfx: EventWriter<audio::PlaySfxEvent>,
    time: Res<Time>,
    chat_branches: Query<&ChatBranch>, // TODO: use Table for faster iteration?
    //chat_choices: Query<&ChatChoice>,
) {
    let now = time.elapsed_seconds_f64();
    for (entity, mut chat) in &mut q_conv {
        if chat.label == "EXIT" {
            debug!("Despawning chat.");
            commands.entity(entity).despawn();
            continue;
        }
        if now < chat.timer {
            continue;
        }

        let branches: Vec<&ChatBranch> = chat_branches.iter()
            .filter(|branch| branch.id == chat.id && branch.label == chat.label)
            .collect();
        if branches.len() != 1 {
            error!("Expected 1 branch with ID '{}' and label '{}', but got {}! Aborting conversation.", chat.id, chat.label, branches.len());
            continue;
        }
        let branch = branches[0];
        log.chat(branch.reply.clone(), branch.name.clone());
        if chat.label == "EXIT" {
            continue;
        }
        chat.label = branch.goto.clone();
        if branch.sound != "" {
            let sfx = audio::str2sfx(branch.sound.as_str());
            ew_sfx.send(audio::PlaySfxEvent(sfx));
        }
        info!("<chat.timer={:.2}, branch.delay={:.2}, epoch={:.2}", chat.timer, branch.delay, now);
        chat.timer = now + branch.delay;
        info!(">chat.timer={:.2}, branch.delay={:.2}, epoch={:.2}", chat.timer, branch.delay, now);
    }
}


//pub enum SuitSystemHandler {
//    Heat,
//    None,
//}
//#[derive(Component)]
//pub struct SuitSystem {
//    pub name: String,
//    pub active: bool,
//    pub power: f32,
//    pub handler: SuitSystemHandler,
//}
//
//impl Default for SuitSystem {
//    fn default() -> Self {
//        Self {
//            name: "Untitled".to_string(),
//            active: true,
//            power: 0.0,
//            handler: SuitSystemHandler::None,
//        }
//    }
//}
//pub fn setup(
//    mut commands: Commands,
//    settings: Res<settings::Settings>,
//) {
//    commands.spawn((
//        Player,
//        SuitSystem {
//            name: "HUD".to_string(),
//            active: settings.hud_active,
//            power: -0.05,
//            ..default()
//        },
//        SuitSystem {
//            name: "Heater".to_string(),
//            handler: SuitSystemHandler::Heat,
//            ..default()
//        }
//    ));
//}