use ecs::component::Local;
use ecs::system::{Into, System};
use ecs::{Component, Query, World};

#[derive(Component)]
struct SomeData
{
    num: u64,
}

#[derive(Component)]
struct Name
{
    name: String,
}

#[derive(Component)]
struct SayHelloState
{
    cnt: usize,
}

fn say_hello(mut query: Query<(SomeData,)>, mut state: Local<SayHelloState>)
{
    for (data,) in query.iter_mut() {
        println!("Hello there. Count {}: {}", state.cnt, data.num);

        state.cnt += 1;
    }
}

fn say_whats_up(mut query: Query<(SomeData, Name)>, mut state: Local<SayHelloState>)
{
    for (data, name) in query.iter_mut() {
        println!(
            "Whats up, {}. Number is {}. Count {}",
            name.name, data.num, state.cnt
        );

        state.cnt += 1;
    }
}

#[derive(Debug, PartialEq, Eq, Hash)]
enum Event
{
    Update,
}

fn main()
{
    let mut world = World::<Event>::new();

    world.register_system(
        Event::Update,
        say_hello
            .into_system()
            .initialize((SayHelloState { cnt: 0 },)),
    );

    world.register_system(
        Event::Update,
        say_whats_up
            .into_system()
            .initialize((SayHelloState { cnt: 0 },)),
    );

    world.create_entity((SomeData { num: 987_654 }, Name { name: "Bob".to_string() }));

    world.create_entity((SomeData { num: 345 },));

    world.emit(&Event::Update);

    println!("Haha");

    world.emit(&Event::Update);
}