use log::{error, info};
use space_crush_app::{App, Error};
use space_crush_common::{
    misc::{init_logger, Vfs},
    Dispatcher,
};
use specs::{World, WorldExt};

fn main() -> Result<(), Error> {
    let vfs = Vfs::new(&["space-crush-app"])?;

    init_logger(&vfs, "log4rs.yml");

    vfs.log_info();

    info!("Application started");

    if let Err(err) = run(vfs) {
        error!("Error while executing application: {}", err);

        return Err(err);
    }

    info!("Application exited");

    Ok(())
}

fn run(vfs: Vfs) -> Result<(), Error> {
    let mut world = World::new();
    world.insert(vfs);

    let mut common = Dispatcher::new(&mut world);
    let mut app = App::new(&mut world)?;

    if !load_world(&mut world, WORLD_FILEPATH)? {
        create_world(&mut world);
    }

    while app.is_running() {
        world.maintain();

        common.process(&world);
        app.process(&world)?;
    }

    save_world(&mut world, WORLD_FILEPATH)?;

    Ok(())
}

fn create_world(world: &mut World) {
    use glc::vector::{Vector2f, Vector4f};
    use space_crush_app::{components::PlayerVisual, misc::PersistWorld};
    use space_crush_common::{
        components::{Owned, Planet, Player, Position, Ship, ShipType, Velocity},
        misc::Persistence,
    };
    use specs::{saveload::MarkedBuilder, Builder};

    let player1 = world
        .create_entity()
        .with(Player {})
        .with(PlayerVisual {
            color: Vector4f::new(0.0, 0.5, 1.0, 0.1),
        })
        .build();

    world
        .create_entity()
        .marked::<<PersistWorld as Persistence>::Marker>()
        .with(Owned { owner: player1 })
        .with(Position {
            pos: Vector2f::default(),
            size: 500.0,
        })
        .with(Planet {})
        .build();

    for i in 0..3 {
        let x = if i & 1 == 0 { 1.0 } else { -1.0 };
        let y = if i & 2 == 0 { 1.0 } else { -1.0 };

        world
            .create_entity()
            .marked::<<PersistWorld as Persistence>::Marker>()
            .with(Owned { owner: player1 })
            .with(Position {
                pos: Vector2f::new(250.0 * x, 250.0 * y),
                size: 30.0,
            })
            .with(Velocity {
                dir: Vector2f::new(i as f32 - 1.0, 1.0).normalize(),
                speed: 0.0,
            })
            .with(Ship {
                type_: match i {
                    0 => ShipType::Fighter,
                    1 => ShipType::Bomber,
                    2 => ShipType::Transporter,
                    _ => unreachable!(),
                },
            })
            .build();
    }
}

fn load_world(world: &mut World, path: &str) -> Result<bool, Error> {
    use serde_json::de::{Deserializer, IoRead};
    use space_crush_app::misc::PersistWorld;
    use space_crush_common::misc::{Persistence, WorldHelper};

    PersistWorld::setup(world);

    let vfs = world.resource::<Vfs>()?;
    let path = vfs.join(path)?;
    if !path.exists() {
        return Ok(false);
    }

    let mut file = path.open_file()?;
    let mut read = IoRead::new(&mut file);
    let mut deserializer = Deserializer::new(&mut read);
    world.deserialize(PersistWorld, &mut deserializer)?;

    Ok(true)
}

fn save_world(world: &mut World, path: &str) -> Result<(), Error> {
    use serde_json::Serializer;
    use space_crush_app::misc::PersistWorld;
    use space_crush_common::misc::WorldHelper;

    let vfs = world.resource::<Vfs>()?;
    let mut file = vfs.join(path)?.create_file()?;
    let mut serializer = Serializer::new(&mut file);
    world.serialize(PersistWorld, &mut serializer)?;

    Ok(())
}

const WORLD_FILEPATH: &str = "resources/world.json";