use crate::{Axis, LayoutLen, Painter, Size};
use std::any::Any;

mod data;
mod handle;
mod like;
mod tag;
mod view;
mod widgets;

pub use data::*;
pub use handle::*;
pub use like::*;
pub use tag::*;
pub use view::*;
pub use widgets::*;

#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
pub enum ChildOrder {
    /// The order in which the parent drew its children.
    #[default]
    Draw,
    /// Ascending visual position on one screen axis. Equal positions keep
    /// draw order; the resolved coordinates are sorted only when queried.
    Axis(Axis),
}

pub trait Widget: Any {
    fn draw(&mut self, painter: &mut Painter);

    fn size_hint(&self, _axis: Axis) -> Option<LayoutLen> {
        None
    }

    fn is_size_independent(&self) -> bool {
        false
    }

    fn requires_exact_region(&self) -> bool {
        false
    }

    fn access_role(&self) -> accesskit::Role {
        accesskit::Role::Unknown
    }

    fn child_order(&self) -> ChildOrder {
        ChildOrder::Draw
    }
}

impl Widget for () {
    fn draw(&mut self, painter: &mut Painter) {
        painter.set_size(Size::ZERO);
    }

    fn is_size_independent(&self) -> bool {
        true
    }

    fn size_hint(&self, _axis: Axis) -> Option<LayoutLen> {
        Some(LayoutLen::ZERO)
    }
}

impl dyn Widget {
    pub fn as_any(&self) -> &dyn Any {
        self
    }

    pub fn as_any_mut(&mut self) -> &mut dyn Any {
        self
    }
}

pub trait WidgetFn<State, W: Widget + ?Sized>: FnOnce(&mut State) -> W {}
impl<State, W: Widget + ?Sized, F: FnOnce(&mut State) -> W> WidgetFn<State, W> for F {}

pub struct WidgetArr<const LEN: usize> {
    pub arr: [StrongWidget; LEN],
}

impl<const LEN: usize> WidgetArr<LEN> {
    pub fn new(arr: [StrongWidget; LEN]) -> Self {
        Self { arr }
    }
}

pub trait WidgetOption<State> {
    fn get(self, state: &mut State) -> Option<StrongWidget>;
}

impl<State> WidgetOption<State> for () {
    fn get(self, _: &mut State) -> Option<StrongWidget> {
        None
    }
}

impl<State, F: FnOnce(&mut State) -> Option<StrongWidget>> WidgetOption<State> for F {
    fn get(self, state: &mut State) -> Option<StrongWidget> {
        self(state)
    }
}