use std::hash::Hash;

use iris_core::util::HashMap;

use crate::prelude::*;

pub struct WidgetSelector<T> {
    current: (T, StrongWidget),
    map: HashMap<T, StrongWidget>,
}

impl<T: Hash + Eq> WidgetSelector<T> {
    pub fn new(key: T, widget: StrongWidget) -> Self {
        Self {
            current: (key, widget),
            map: Default::default(),
        }
    }

    pub fn set(&mut self, key: T, widget: StrongWidget) {
        self.map.insert(key, widget);
    }

    pub fn select(&mut self, key: T) -> bool {
        if let Some(val) = self.map.remove(&key) {
            let mut new = (key, val);
            std::mem::swap(&mut new, &mut self.current);
            self.map.insert(new.0, new.1);
            true
        } else {
            false
        }
    }
}

impl<T: 'static> Widget for WidgetSelector<T> {
    fn draw(&mut self, painter: &mut Painter) {
        painter.widget(&self.current.1);
    }

    fn desired_width(&mut self, ctx: &mut SizeCtx) -> Len {
        ctx.width(&self.current.1)
    }

    fn desired_height(&mut self, ctx: &mut SizeCtx) -> Len {
        ctx.height(&self.current.1)
    }
}