use ecs::event::{Event, Id as EventId};
use ecs::flags::Flags;
use ecs::{Component, Query, World};

#[derive(Component)]
struct Wool
{
    remaining: u32,
}

#[derive(Component)]
struct Health
{
    health: u32,
}

#[derive(Component)]
struct Name
{
    name: &'static str,
}

fn sheer(query: Query<(Wool, Name)>)
{
    for (mut wool, name) in &query {
        if wool.remaining == 0 {
            println!("{} Has no wool left", name.name);

            continue;
        }

        // Sheer the whool
        wool.remaining -= 5;

        println!("Sheered 5 wool from {}", name.name);
    }
}

fn feed(query: Query<(Health, Name)>)
{
    for (mut health, name) in &query {
        health.health += 1;

        println!("Feeded {} which gained 1 health", name.name);
    }
}

fn age(query: Query<(Health, Name)>, mut flags: Flags)
{
    for (mut health, name) in &query {
        if health.health <= 2 {
            health.health = 0;

            println!("{} passed away", name.name);

            flags.stop();

            continue;
        }

        health.health -= 2;

        println!("{} aged and lost 2 health", name.name);
    }
}

#[derive(Debug)]
struct EventA;

impl Event for EventA
{
    fn id(&self) -> EventId
    {
        EventId::of::<Self>()
    }
}

#[derive(Debug)]
struct EventB;

impl Event for EventB
{
    fn id(&self) -> EventId
    {
        EventId::of::<Self>()
    }
}

#[derive(Debug)]
struct EventC;

impl Event for EventC
{
    fn id(&self) -> EventId
    {
        EventId::of::<Self>()
    }
}

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

    world.register_system(&EventA, sheer);
    world.register_system(&EventB, feed);
    world.register_system(&EventC, age);

    world.create_entity((
        Wool { remaining: 30 },
        Health { health: 3 },
        Name { name: "Bessy" },
    ));

    world.event_loop::<(EventA, EventB, EventC)>();
}