update components

crates/ui/src/anchored.rs

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+//! This is a fork of gpui's anchored element that adds support for offsetting
+//! https://github.com/zed-industries/zed/blob/b06f4088a3565c5e30663106ff79c1ced645d87a/crates/gpui/src/elements/anchored.rs
+use gpui::{
+    point, px, AnyElement, App, Axis, Bounds, Display, Edges, Element, GlobalElementId, Half,
+    InspectorElementId, IntoElement, LayoutId, ParentElement, Pixels, Point, Position, Size, Style,
+    Window,
+};
+use smallvec::SmallVec;
+
+use crate::Anchor;
+
+/// The state that the anchored element element uses to track its children.
+pub struct AnchoredState {
+    child_layout_ids: SmallVec<[LayoutId; 4]>,
+}
+
+/// An anchored element that can be used to display UI that
+/// will avoid overflowing the window bounds.
+pub(crate) struct Anchored {
+    children: SmallVec<[AnyElement; 2]>,
+    anchor_corner: Anchor,
+    fit_mode: AnchoredFitMode,
+    anchor_position: Option<Point<Pixels>>,
+    position_mode: AnchoredPositionMode,
+    offset: Option<Point<Pixels>>,
+}
+
+/// anchored gives you an element that will avoid overflowing the window bounds.
+/// Its children should have no margin to avoid measurement issues.
+pub(crate) fn anchored() -> Anchored {
+    Anchored {
+        children: SmallVec::new(),
+        anchor_corner: Anchor::TopLeft,
+        fit_mode: AnchoredFitMode::SwitchAnchor,
+        anchor_position: None,
+        position_mode: AnchoredPositionMode::Window,
+        offset: None,
+    }
+}
+
+#[allow(dead_code)]
+impl Anchored {
+    /// Sets which corner of the anchored element should be anchored to the current position.
+    pub fn anchor(mut self, anchor: Anchor) -> Self {
+        self.anchor_corner = anchor;
+        self
+    }
+
+    /// Sets the position in window coordinates
+    /// (otherwise the location the anchored element is rendered is used)
+    pub fn position(mut self, anchor: Point<Pixels>) -> Self {
+        self.anchor_position = Some(anchor);
+        self
+    }
+
+    /// Offset the final position by this amount.
+    /// Useful when you want to anchor to an element but offset from it, such as in PopoverMenu.
+    pub fn offset(mut self, offset: Point<Pixels>) -> Self {
+        self.offset = Some(offset);
+        self
+    }
+
+    /// Sets the position mode for this anchored element. Local will have this
+    /// interpret its [`Anchored::position`] as relative to the parent element.
+    /// While Window will have it interpret the position as relative to the window.
+    pub fn position_mode(mut self, mode: AnchoredPositionMode) -> Self {
+        self.position_mode = mode;
+        self
+    }
+
+    /// Snap to window edge instead of switching anchor corner when an overflow would occur.
+    pub fn snap_to_window(mut self) -> Self {
+        self.fit_mode = AnchoredFitMode::SnapToWindow;
+        self
+    }
+
+    /// Snap to window edge and leave some margins.
+    pub fn snap_to_window_with_margin(mut self, edges: impl Into<Edges<Pixels>>) -> Self {
+        self.fit_mode = AnchoredFitMode::SnapToWindowWithMargin(edges.into());
+        self
+    }
+}
+
+impl ParentElement for Anchored {
+    fn extend(&mut self, elements: impl IntoIterator<Item = AnyElement>) {
+        self.children.extend(elements)
+    }
+}
+
+impl Element for Anchored {
+    type PrepaintState = ();
+    type RequestLayoutState = AnchoredState;
+
+    fn id(&self) -> Option<gpui::ElementId> {
+        None
+    }
+
+    fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {
+        None
+    }
+
+    fn request_layout(
+        &mut self,
+        _id: Option<&GlobalElementId>,
+        _inspector_id: Option<&InspectorElementId>,
+        window: &mut Window,
+        cx: &mut App,
+    ) -> (gpui::LayoutId, Self::RequestLayoutState) {
+        let child_layout_ids = self
+            .children
+            .iter_mut()
+            .map(|child| child.request_layout(window, cx))
+            .collect::<SmallVec<_>>();
+
+        let anchored_style = Style {
+            position: Position::Absolute,
+            display: Display::Flex,
+            ..Style::default()
+        };
+
+        let layout_id = window.request_layout(anchored_style, child_layout_ids.iter().copied(), cx);
+
+        (layout_id, AnchoredState { child_layout_ids })
+    }
+
+    fn prepaint(
+        &mut self,
+        _id: Option<&GlobalElementId>,
+        _inspector_id: Option<&InspectorElementId>,
+        bounds: Bounds<Pixels>,
+        request_layout: &mut Self::RequestLayoutState,
+        window: &mut Window,
+        cx: &mut App,
+    ) {
+        if request_layout.child_layout_ids.is_empty() {
+            return;
+        }
+
+        let mut child_min = point(Pixels::MAX, Pixels::MAX);
+        let mut child_max = Point::default();
+        for child_layout_id in &request_layout.child_layout_ids {
+            let child_bounds = window.layout_bounds(*child_layout_id);
+            child_min = child_min.min(&child_bounds.origin);
+            child_max = child_max.max(&child_bounds.bottom_right());
+        }
+        let size: Size<Pixels> = (child_max - child_min).into();
+
+        let (origin, mut desired) = self.position_mode.get_position_and_bounds(
+            self.anchor_position,
+            self.anchor_corner,
+            size,
+            bounds,
+            self.offset,
+        );
+
+        let limits = Bounds {
+            origin: Point::default(),
+            size: window.viewport_size(),
+        };
+
+        if self.fit_mode == AnchoredFitMode::SwitchAnchor {
+            let mut anchor_corner = self.anchor_corner;
+
+            if desired.left() < limits.left() || desired.right() > limits.right() {
+                let switched = Bounds::from_corner_and_size(
+                    anchor_corner
+                        .other_side_corner_along(Axis::Horizontal)
+                        .into(),
+                    origin,
+                    size,
+                );
+                if !(switched.left() < limits.left() || switched.right() > limits.right()) {
+                    anchor_corner = anchor_corner.other_side_corner_along(Axis::Horizontal);
+                    desired = switched
+                }
+            }
+
+            if desired.top() < limits.top() || desired.bottom() > limits.bottom() {
+                let switched = Bounds::from_corner_and_size(
+                    anchor_corner.other_side_corner_along(Axis::Vertical).into(),
+                    origin,
+                    size,
+                );
+                if !(switched.top() < limits.top() || switched.bottom() > limits.bottom()) {
+                    desired = switched;
+                }
+            }
+        }
+
+        let client_inset = window.client_inset().unwrap_or(px(0.));
+        let edges = match self.fit_mode {
+            AnchoredFitMode::SnapToWindowWithMargin(edges) => edges,
+            _ => Edges::default(),
+        }
+        .map(|edge| *edge + client_inset);
+
+        // Snap the horizontal edges of the anchored element to the horizontal edges of the window if
+        // its horizontal bounds overflow, aligning to the left if it is wider than the limits.
+        if desired.right() > limits.right() {
+            desired.origin.x -= desired.right() - limits.right() + edges.right;
+        }
+        if desired.left() < limits.left() {
+            desired.origin.x = limits.origin.x + edges.left;
+        }
+
+        // Snap the vertical edges of the anchored element to the vertical edges of the window if
+        // its vertical bounds overflow, aligning to the top if it is taller than the limits.
+        if desired.bottom() > limits.bottom() {
+            desired.origin.y -= desired.bottom() - limits.bottom() + edges.bottom;
+        }
+        if desired.top() < limits.top() {
+            desired.origin.y = limits.origin.y + edges.top;
+        }
+
+        let offset = desired.origin - bounds.origin;
+        let offset = point(offset.x.round(), offset.y.round());
+
+        window.with_element_offset(offset, |window| {
+            for child in &mut self.children {
+                child.prepaint(window, cx);
+            }
+        })
+    }
+
+    fn paint(
+        &mut self,
+        _id: Option<&GlobalElementId>,
+        _inspector_id: Option<&InspectorElementId>,
+        _bounds: Bounds<Pixels>,
+        _request_layout: &mut Self::RequestLayoutState,
+        _prepaint: &mut Self::PrepaintState,
+        window: &mut Window,
+        cx: &mut App,
+    ) {
+        for child in &mut self.children {
+            child.paint(window, cx);
+        }
+    }
+}
+
+impl IntoElement for Anchored {
+    type Element = Self;
+
+    fn into_element(self) -> Self::Element {
+        self
+    }
+}
+
+/// Which algorithm to use when fitting the anchored element to be inside the window.
+#[allow(dead_code)]
+#[derive(Copy, Clone, PartialEq)]
+pub enum AnchoredFitMode {
+    /// Snap the anchored element to the window edge.
+    SnapToWindow,
+    /// Snap to window edge and leave some margins.
+    SnapToWindowWithMargin(Edges<Pixels>),
+    /// Switch which corner anchor this anchored element is attached to.
+    SwitchAnchor,
+}
+
+/// Which algorithm to use when positioning the anchored element.
+#[allow(dead_code)]
+#[derive(Copy, Clone, PartialEq)]
+pub enum AnchoredPositionMode {
+    /// Position the anchored element relative to the window.
+    Window,
+    /// Position the anchored element relative to its parent.
+    Local,
+}
+
+impl AnchoredPositionMode {
+    fn get_position_and_bounds(
+        &self,
+        anchor_position: Option<Point<Pixels>>,
+        anchor_corner: Anchor,
+        size: Size<Pixels>,
+        bounds: Bounds<Pixels>,
+        offset: Option<Point<Pixels>>,
+    ) -> (Point<Pixels>, Bounds<Pixels>) {
+        let offset = offset.unwrap_or_default();
+
+        match self {
+            AnchoredPositionMode::Window => {
+                let anchor_position = anchor_position.unwrap_or(bounds.origin);
+                let bounds =
+                    Self::from_corner_and_size(anchor_corner, anchor_position + offset, size);
+                (anchor_position, bounds)
+            }
+            AnchoredPositionMode::Local => {
+                let anchor_position = anchor_position.unwrap_or_default();
+                let bounds = Self::from_corner_and_size(
+                    anchor_corner,
+                    bounds.origin + anchor_position + offset,
+                    size,
+                );
+                (anchor_position, bounds)
+            }
+        }
+    }
+
+    // Ref https://github.com/zed-industries/zed/blob/b06f4088a3565c5e30663106ff79c1ced645d87a/crates/gpui/src/geometry.rs#L863
+    fn from_corner_and_size(
+        anchor: Anchor,
+        origin: Point<Pixels>,
+        size: Size<Pixels>,
+    ) -> Bounds<Pixels> {
+        let origin = match anchor {
+            Anchor::TopLeft => origin,
+            Anchor::TopCenter => Point {
+                x: origin.x - size.width.half(),
+                y: origin.y,
+            },
+            Anchor::TopRight => Point {
+                x: origin.x - size.width,
+                y: origin.y,
+            },
+            Anchor::BottomLeft => Point {
+                x: origin.x,
+                y: origin.y - size.height,
+            },
+            Anchor::BottomCenter => Point {
+                x: origin.x - size.width.half(),
+                y: origin.y - size.height,
+            },
+            Anchor::BottomRight => Point {
+                x: origin.x - size.width,
+                y: origin.y - size.height,
+            },
+        };
+
+        Bounds { origin, size }
+    }
+}