learn how workspaces + proc macros work & restructure everything

core/src/layout/widget/handle.rs

@@ -0,0 +1,163 @@
+use std::{
+    cell::{Ref, RefMut},
+    marker::Unsize,
+    ops::CoerceUnsized,
+    sync::mpsc::Sender,
+};
+
+use crate::{
+    layout::{IdFnTag, IdTag, Ui, Widget, WidgetLike},
+    util::{Handle, Id, WeakHandle},
+};
+
+/// An handle for a widget in a UI.
+///
+/// TODO: ergonomic clones when they get put in rust-analyzer & don't cause ICEs?
+pub struct WidgetRef<W: ?Sized = dyn Widget>(Handle<Inner<W>>);
+pub struct WeakWidgetRef<W: ?Sized = dyn Widget>(WeakHandle<Inner<W>>);
+
+struct Inner<W: ?Sized> {
+    id: Id,
+    send: Sender<WidgetUpdate>,
+    label: String,
+    widget: W,
+}
+
+pub enum WidgetUpdate {
+    Drop(Id),
+    Mutate(Id),
+}
+
+impl<W> PartialEq for WidgetRef<W> {
+    fn eq(&self, other: &Self) -> bool {
+        self.id() == other.id()
+    }
+}
+
+impl<W> std::fmt::Debug for WidgetRef<W> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        self.id().fmt(f)
+    }
+}
+
+impl<W: ?Sized> Clone for WidgetRef<W> {
+    fn clone(&self) -> Self {
+        Self(self.0.clone())
+    }
+}
+
+impl<W: Widget> WidgetRef<W> {
+    pub(super) fn new(id: Id, widget: W, send: Sender<WidgetUpdate>) -> Self {
+        let mut label = std::any::type_name::<W>().to_string();
+        if let (Some(first), Some(last)) = (label.find(":"), label.rfind(":")) {
+            label = label.split_at(first).0.to_string() + "::" + label.split_at(last + 1).1;
+        }
+        Self(
+            Inner {
+                widget,
+                id,
+                send,
+                label,
+            }
+            .into(),
+        )
+    }
+}
+
+impl<W: Widget + ?Sized + Unsize<dyn Widget>> WidgetRef<W> {
+    pub fn any(self) -> WidgetRef<dyn Widget> {
+        WidgetRef(self.0)
+    }
+    pub fn as_any(&self) -> WidgetRef<dyn Widget> {
+        WidgetRef(self.0.clone())
+    }
+}
+
+impl<W: ?Sized> WidgetRef<W> {
+    pub fn id(&self) -> Id {
+        self.0.get().id
+    }
+
+    pub fn get(&self) -> Ref<'_, W> {
+        Ref::map(self.0.get(), |i| &i.widget)
+    }
+
+    pub fn get_mut(&self) -> RefMut<'_, W> {
+        let inner = self.0.get_mut();
+        let _ = inner.send.send(WidgetUpdate::Mutate(inner.id));
+        RefMut::map(inner, |i| &mut i.widget)
+    }
+
+    pub fn get_mut_quiet(&self) -> RefMut<'_, W> {
+        RefMut::map(self.0.get_mut(), |i| &mut i.widget)
+    }
+
+    pub fn get_label(&self) -> Ref<'_, String> {
+        Ref::map(self.0.get(), |i| &i.label)
+    }
+
+    pub fn set_label(&self, label: impl Into<String>) {
+        self.0.get_mut().label = label.into();
+    }
+
+    pub fn refs(&self) -> usize {
+        self.0.refs()
+    }
+
+    pub fn weak(&self) -> WeakWidgetRef<W> {
+        WeakWidgetRef(self.0.weak())
+    }
+}
+
+impl<W: ?Sized> WeakWidgetRef<W> {
+    /// should guarantee that widget is still valid to prevent indexing failures
+    pub(crate) fn expect_strong(&self) -> WidgetRef<W> {
+        WidgetRef(self.0.strong().expect("widget should not be dropped"))
+    }
+}
+
+impl<W: Widget + ?Sized + Unsize<dyn Widget>> WeakWidgetRef<W> {
+    pub fn any(self) -> WeakWidgetRef<dyn Widget> {
+        WeakWidgetRef(self.0.clone())
+    }
+}
+
+impl<W: ?Sized> Drop for Inner<W> {
+    fn drop(&mut self) {
+        let _ = self.send.send(WidgetUpdate::Drop(self.id));
+    }
+}
+
+pub trait WidgetIdFn<W: ?Sized = dyn Widget>: FnOnce(&mut Ui) -> WidgetRef<W> {}
+impl<W: ?Sized, F: FnOnce(&mut Ui) -> WidgetRef<W>> WidgetIdFn<W> for F {}
+
+pub trait WidgetRet: FnOnce(&mut Ui) -> WidgetRef {}
+impl<F: FnOnce(&mut Ui) -> WidgetRef> WidgetRet for F {}
+
+impl<W: Widget + ?Sized + Unsize<dyn Widget> + 'static> WidgetLike<IdTag> for WidgetRef<W> {
+    type Widget = W;
+    fn add(self, _: &mut Ui) -> WidgetRef<W> {
+        self
+    }
+}
+
+impl<W: Widget + ?Sized + Unsize<dyn Widget> + 'static, F: FnOnce(&mut Ui) -> WidgetRef<W>>
+    WidgetLike<IdFnTag> for F
+{
+    type Widget = W;
+    fn add(self, ui: &mut Ui) -> WidgetRef<W> {
+        self(ui)
+    }
+}
+
+pub trait IdLike<W> {
+    fn id(&self) -> Id;
+}
+
+impl<W> IdLike<W> for WidgetRef<W> {
+    fn id(&self) -> Id {
+        self.id()
+    }
+}
+
+impl<W: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<WidgetRef<U>> for WidgetRef<W> {}

core/src/layout/widget/like.rs

@@ -0,0 +1,79 @@
+use super::*;
+use std::marker::Unsize;
+
+pub trait WidgetLike<Tag> {
+    type Widget: Widget + ?Sized + Unsize<dyn Widget> + 'static;
+
+    fn add(self, ui: &mut Ui) -> WidgetRef<Self::Widget>;
+
+    fn with_id<W2>(
+        self,
+        f: impl FnOnce(&mut Ui, WidgetRef<Self::Widget>) -> WidgetRef<W2>,
+    ) -> impl WidgetIdFn<W2>
+    where
+        Self: Sized,
+    {
+        move |ui| {
+            let id = self.add(ui);
+            f(ui, id)
+        }
+    }
+
+    fn set_root(self, ui: &mut Ui)
+    where
+        Self: Sized,
+    {
+        ui.set_root(self);
+    }
+}
+
+pub struct WidgetArr<const LEN: usize> {
+    pub arr: [WidgetRef; LEN],
+}
+
+impl<const LEN: usize> WidgetArr<LEN> {
+    pub fn new(arr: [WidgetRef; LEN]) -> Self {
+        Self { arr }
+    }
+}
+
+pub trait WidgetArrLike<const LEN: usize, Tag> {
+    fn ui(self, ui: &mut Ui) -> WidgetArr<LEN>;
+}
+
+impl<const LEN: usize> WidgetArrLike<LEN, ArrTag> for WidgetArr<LEN> {
+    fn ui(self, _: &mut Ui) -> WidgetArr<LEN> {
+        self
+    }
+}
+
+// I hate this language it's so bad why do I even use it
+macro_rules! impl_widget_arr {
+    ($n:expr;$($W:ident)*) => {
+        impl_widget_arr!($n;$($W)*;$(${concat($W,Tag)})*);
+    };
+    ($n:expr;$($W:ident)*;$($Tag:ident)*) => {
+        impl<$($W: WidgetLike<$Tag>,$Tag,)*> WidgetArrLike<$n, ($($Tag,)*)> for ($($W,)*) {
+            fn ui(self, ui: &mut Ui) -> WidgetArr<$n> {
+                #[allow(non_snake_case)]
+                let ($($W,)*) = self;
+                WidgetArr::new(
+                    [$($W.add(ui),)*],
+                )
+            }
+        }
+    };
+}
+
+impl_widget_arr!(1;A);
+impl_widget_arr!(2;A B);
+impl_widget_arr!(3;A B C);
+impl_widget_arr!(4;A B C D);
+impl_widget_arr!(5;A B C D E);
+impl_widget_arr!(6;A B C D E F);
+impl_widget_arr!(7;A B C D E F G);
+impl_widget_arr!(8;A B C D E F G H);
+impl_widget_arr!(9;A B C D E F G H I);
+impl_widget_arr!(10;A B C D E F G H I J);
+impl_widget_arr!(11;A B C D E F G H I J K);
+impl_widget_arr!(12;A B C D E F G H I J K L);

core/src/layout/widget/mod.rs

@@ -0,0 +1,63 @@
+mod handle;
+mod like;
+mod tag;
+mod widgets;
+
+pub use handle::*;
+pub use like::*;
+pub use tag::*;
+pub use widgets::*;
+
+use crate::layout::{Len, Painter, SizeCtx, Ui};
+
+pub trait Widget: 'static {
+    fn draw(&mut self, painter: &mut Painter);
+    fn desired_width(&mut self, ctx: &mut SizeCtx) -> Len;
+    fn desired_height(&mut self, ctx: &mut SizeCtx) -> Len;
+}
+
+impl Widget for () {
+    fn draw(&mut self, _: &mut Painter) {}
+    fn desired_width(&mut self, _: &mut SizeCtx) -> Len {
+        Len::ZERO
+    }
+    fn desired_height(&mut self, _: &mut SizeCtx) -> Len {
+        Len::ZERO
+    }
+}
+
+/// A function that returns a widget given a UI.
+/// Useful for defining trait functions on widgets that create a parent widget so that the children
+/// don't need to be IDs yet
+pub trait WidgetFn<W: Widget + ?Sized>: FnOnce(&mut Ui) -> W {}
+impl<W: Widget, F: FnOnce(&mut Ui) -> W> WidgetFn<W> for F {}
+
+impl<W: Widget, F: FnOnce(&mut Ui) -> W> WidgetLike<FnTag> for F {
+    type Widget = W;
+    fn add(self, ui: &mut Ui) -> WidgetRef<W> {
+        self(ui).add(ui)
+    }
+}
+
+impl<W: Widget> WidgetLike<WidgetTag> for W {
+    type Widget = W;
+    fn add(self, ui: &mut Ui) -> WidgetRef<W> {
+        ui.add_widget(self)
+    }
+}
+
+pub trait WidgetOption {
+    fn get(self, ui: &mut Ui) -> Option<WidgetRef>;
+}
+
+impl WidgetOption for () {
+    fn get(self, _: &mut Ui) -> Option<WidgetRef> {
+        None
+    }
+}
+
+impl<F: FnOnce(&mut Ui) -> Option<WidgetRef>> WidgetOption for F {
+    fn get(self, ui: &mut Ui) -> Option<WidgetRef> {
+        self(ui)
+    }
+}

core/src/layout/widget/tag.rs

@@ -0,0 +1,5 @@
+pub struct WidgetTag;
+pub struct FnTag;
+pub struct IdTag;
+pub struct IdFnTag;
+pub struct ArrTag;

core/src/layout/widget/widgets.rs

@@ -0,0 +1,50 @@
+use std::sync::mpsc::Sender;
+
+use crate::{
+    layout::{WeakWidgetRef, Widget, WidgetRef, WidgetUpdate},
+    util::{HashMap, Id, IdTracker},
+};
+
+pub struct Widgets {
+    ids: IdTracker,
+    map: HashMap<Id, WeakWidgetRef>,
+    send: Sender<WidgetUpdate>,
+}
+
+impl Widgets {
+    pub fn new(send: Sender<WidgetUpdate>) -> Self {
+        Self {
+            ids: IdTracker::default(),
+            map: HashMap::default(),
+            send,
+        }
+    }
+
+    pub fn get(&self, id: Id) -> WidgetRef {
+        self.map.get(&id).unwrap().expect_strong()
+    }
+
+    pub fn insert<W: Widget>(&mut self, widget: W) -> WidgetRef<W> {
+        let id = self.ids.next();
+        let rf = WidgetRef::new(id, widget, self.send.clone());
+        self.map.insert(id, rf.weak().any());
+        rf
+    }
+
+    pub fn delete(&mut self, id: Id) {
+        self.map.remove(&id);
+        self.ids.free(id);
+    }
+
+    pub fn reserve(&mut self) -> Id {
+        self.ids.next()
+    }
+
+    pub fn len(&self) -> usize {
+        self.map.len()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.map.is_empty()
+    }
+}