mod ctx;
mod manager;
mod rsc;

pub use ctx::*;
pub use manager::*;
pub use rsc::*;

pub trait Event: Sized + 'static + Clone {
    type Data<'a>: Clone = ();
    type State: Default = ();
    /// State the whole event type keeps, rather than one copy per widget.
    type Global: Default = ();
    #[allow(unused_variables)]
    fn should_run<'a>(&self, data: &Self::Data<'a>) -> Option<Self::Data<'a>> {
        Some(data.clone())
    }

    /// Whether having run on this data uses up whatever triggered it, so
    /// nothing further should see it.
    #[allow(unused_variables)]
    fn consumes(&self, data: &Self::Data<'_>) -> bool {
        false
    }
}

pub trait EventLike {
    type Event: Event;
    fn into_event(self) -> Self::Event;
}

impl<E: Event> EventLike for E {
    type Event = Self;

    fn into_event(self) -> Self::Event {
        self
    }
}

pub trait EventFn<Rsc: HasEvents, Data>: Fn(EventCtx<Rsc, Data>, &mut Rsc) + 'static {}
impl<Rsc: HasEvents, F: Fn(EventCtx<Rsc, Data>, &mut Rsc) + 'static, Data> EventFn<Rsc, Data>
    for F
{
}

pub trait WidgetEventFn<Rsc: HasEvents, Data, W: ?Sized>:
    Fn(EventIdCtx<Rsc, Data, W>, &mut Rsc) + 'static
{
}
impl<Rsc: HasEvents, F: Fn(EventIdCtx<Rsc, Data, W>, &mut Rsc) + 'static, Data, W: ?Sized>
    WidgetEventFn<Rsc, Data, W> for F
{
}