Remove top-level stack layouter from tree layouter 🗑

1 files changed, 58 insertions, 29 deletions

diff --git a/src/layout/flex.rs b/src/layout/flex.rs
index 01086c32..dfe38bba 100644
--- a/src/layout/flex.rs
+++ b/src/layout/flex.rs
@@ -20,8 +20,8 @@ use super::*;
 #[derive(Debug, Clone)]
 pub struct FlexLayouter {
     ctx: FlexContext,
-    units: Vec<FlexUnit>,
     stack: StackLayouter,
+    units: Vec<FlexUnit>,
 
     usable: Size,
     run: FlexRun,
@@ -35,6 +35,7 @@ pub struct FlexLayouter {
 pub struct FlexContext {
     pub spaces: LayoutSpaces,
     pub axes: LayoutAxes,
+    pub shrink_to_fit: bool,
     /// The spacing between two lines of boxes.
     pub flex_spacing: Size,
 }
@@ -63,6 +64,7 @@ impl FlexLayouter {
         let stack = StackLayouter::new(StackContext {
             spaces: ctx.spaces,
             axes: ctx.axes,
+            shrink_to_fit: ctx.shrink_to_fit,
         });
 
         FlexLayouter {
@@ -88,14 +90,20 @@ impl FlexLayouter {
         }
     }
 
+    /// Add a forced run break.
+    pub fn add_run_break(&mut self) {
+        self.units.push(FlexUnit::Break);
+    }
+
     /// Add a space box which can be replaced by a run break.
-    pub fn add_space(&mut self, space: Size) {
+    pub fn add_primary_space(&mut self, space: Size) {
         self.units.push(FlexUnit::Space(space));
     }
 
-    /// Add a forced run break.
-    pub fn add_break(&mut self) {
-        self.units.push(FlexUnit::Break);
+    pub fn add_secondary_space(&mut self, space: Size) -> LayoutResult<()> {
+        self.finish_box()?;
+        self.stack.add_space(space);
+        Ok(())
     }
 
     /// Update the axes in use by this flex layouter.
@@ -109,6 +117,21 @@ impl FlexLayouter {
     /// with borrowed layouters. The state of the layouter is not reset.
     /// Therefore, it should not be further used after calling `finish`.
     pub fn finish(&mut self) -> LayoutResult<MultiLayout> {
+        self.finish_box()?;
+        Ok(self.stack.finish())
+    }
+
+    pub fn finish_layout(&mut self, hard: bool) -> LayoutResult<()> {
+        self.finish_box()?;
+        self.stack.finish_layout(hard);
+        Ok(())
+    }
+
+    pub fn finish_box(&mut self) -> LayoutResult<()> {
+        if self.box_is_empty() {
+            return Ok(());
+        }
+
         // Move the units out of the layout because otherwise, we run into
         // ownership problems.
         let units = std::mem::replace(&mut self.units, vec![]);
@@ -131,7 +154,28 @@ impl FlexLayouter {
         // Finish the last flex run.
         self.finish_run()?;
 
-        Ok(self.stack.finish())
+        Ok(())
+    }
+
+    /// Finish the current flex run.
+    fn finish_run(&mut self) -> LayoutResult<()> {
+        let mut actions = LayoutActionList::new();
+        for (x, layout) in self.run.content.drain(..) {
+            let position = self.ctx.axes.specialize(Size2D::with_x(x));
+            actions.add_layout(position, layout);
+        }
+
+        self.run.size.y += self.ctx.flex_spacing;
+
+        self.stack.add(Layout {
+            dimensions: self.ctx.axes.specialize(self.run.size),
+            actions: actions.into_vec(),
+            debug_render: false,
+        })?;
+
+        self.run.size = Size2D::zero();
+
+        Ok(())
     }
 
     /// Layout a content box into the current flex run or start a new run if
@@ -150,7 +194,7 @@ impl FlexLayouter {
                     Err(LayoutError::NotEnoughSpace("cannot fix box into flex run"))?;
                 }
 
-                self.stack.add_break(true);
+                self.stack.finish_layout(true);
                 self.usable = self.stack.usable().x;
             }
 
@@ -174,34 +218,19 @@ impl FlexLayouter {
         // TODO
     }
 
-    /// Finish the current flex run.
-    fn finish_run(&mut self) -> LayoutResult<()> {
-        let mut actions = LayoutActionList::new();
-        for (x, layout) in self.run.content.drain(..) {
-            let position = self.ctx.axes.specialize(Size2D::with_x(x));
-            actions.add_layout(position, layout);
-        }
-
-        self.run.size.y += self.ctx.flex_spacing;
-
-        self.stack.add(Layout {
-            dimensions: self.ctx.axes.specialize(self.run.size),
-            actions: actions.into_vec(),
-            debug_render: false,
-        })?;
-
-        self.run.size = Size2D::zero();
-
-        Ok(())
-    }
-
     /// This layouter's context.
     pub fn ctx(&self) -> FlexContext {
         self.ctx
     }
 
+    pub fn remaining(&self) -> LayoutResult<LayoutSpaces> {
+        let mut future = self.clone();
+        future.finish_box()?;
+        Ok(future.stack.remaining())
+    }
+
     /// Whether this layouter contains any items.
-    pub fn is_empty(&self) -> bool {
+    pub fn box_is_empty(&self) -> bool {
         self.units.is_empty()
     }
 }