geometry: make graph private, encapsulate all mutating usage of it

src/layout/dot.rs

@@ -1,6 +1,8 @@
 use enum_dispatch::enum_dispatch;
 use geo::Point;
 
+use petgraph::stable_graph::NodeIndex;
+
 use crate::{
     graph::{GenericIndex, GetNodeIndex},
     layout::{
@@ -16,7 +18,7 @@ use crate::{
     math::Circle,
 };
 
-use petgraph::stable_graph::NodeIndex;
+use super::geometry::SetPos;
 
 #[enum_dispatch(GetNodeIndex, MakePrimitive)]
 #[derive(Debug, Clone, Copy, PartialEq)]
@@ -46,7 +48,7 @@ impl TryFrom<GeometryIndex> for DotIndex {
     }
 }
 
-#[enum_dispatch(GetPos, GetWidth)]
+#[enum_dispatch(GetPos, SetPos, GetWidth)]
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub enum DotWeight {
     Fixed(FixedDotWeight),
@@ -91,6 +93,12 @@ impl GetPos for FixedDotWeight {
     }
 }
 
+impl SetPos for FixedDotWeight {
+    fn set_pos(&mut self, pos: Point) {
+        self.circle.pos = pos
+    }
+}
+
 impl GetWidth for FixedDotWeight {
     fn width(&self) -> f64 {
         self.circle.r * 2.0
@@ -112,6 +120,12 @@ impl GetPos for LooseDotWeight {
     }
 }
 
+impl SetPos for LooseDotWeight {
+    fn set_pos(&mut self, pos: Point) {
+        self.circle.pos = pos
+    }
+}
+
 impl GetWidth for LooseDotWeight {
     fn width(&self) -> f64 {
         self.circle.r * 2.0

src/layout/geometry/geometry.rs

@@ -24,6 +24,11 @@ pub trait GetPos {
     fn pos(&self) -> Point;
 }
 
+#[enum_dispatch]
+pub trait SetPos {
+    fn set_pos(&mut self, pos: Point);
+}
+
 #[enum_dispatch]
 pub trait GetWidth {
     fn width(&self) -> f64;
@@ -41,7 +46,7 @@ pub enum GeometryLabel {
     Core,
 }
 
-pub trait DotWeightTrait<GW>: GetPos + GetWidth + Into<GW> + Copy {}
+pub trait DotWeightTrait<GW>: GetPos + SetPos + GetWidth + Into<GW> + Copy {}
 pub trait SegWeightTrait<GW>: GetWidth + Into<GW> + Copy {}
 pub trait BendWeightTrait<GW>: GetOffset + GetWidth + Into<GW> + Copy {}
 
@@ -56,7 +61,7 @@ pub struct Geometry<
     SI: GetNodeIndex + Into<GI> + Copy,
     BI: GetNodeIndex + Into<GI> + Copy,
 > {
-    pub graph: StableDiGraph<GW, GeometryLabel, usize>,
+    graph: StableDiGraph<GW, GeometryLabel, usize>,
     weight_marker: PhantomData<GW>,
     dot_weight_marker: PhantomData<DW>,
     seg_weight_marker: PhantomData<SW>,
@@ -140,6 +145,40 @@ impl<
         bend
     }
 
+    pub fn remove(&mut self, node: GI) {
+        self.graph.remove_node(node.node_index());
+    }
+
+    pub fn move_dot(&mut self, dot: DI, to: Point) {
+        let mut weight = self.dot_weight(dot);
+        weight.set_pos(to);
+        *self.graph.node_weight_mut(dot.node_index()).unwrap() = weight.into()
+    }
+
+    pub fn flip_bend(&mut self, bend: BI) {
+        let (from, to) = self.bend_joints(bend);
+        let from_edge_weight = self
+            .graph
+            .remove_edge(
+                self.graph
+                    .find_edge(from.node_index(), bend.node_index())
+                    .unwrap(),
+            )
+            .unwrap();
+        let to_edge_weight = self
+            .graph
+            .remove_edge(
+                self.graph
+                    .find_edge(bend.node_index(), to.node_index())
+                    .unwrap(),
+            )
+            .unwrap();
+        self.graph
+            .update_edge(from.node_index(), bend.node_index(), to_edge_weight);
+        self.graph
+            .update_edge(bend.node_index(), to.node_index(), from_edge_weight);
+    }
+
     pub fn reattach_bend(&mut self, bend: BI, maybe_new_inner: Option<BI>) {
         if let Some(old_inner_edge) = self
             .graph

src/layout/layout.rs

@@ -18,7 +18,7 @@ use crate::guide::Guide;
 use crate::layout::bend::BendIndex;
 use crate::layout::dot::DotWeight;
 use crate::layout::geometry::{
-    BendWeightTrait, DotWeightTrait, Geometry, GeometryLabel, SegWeightTrait,
+    BendWeightTrait, DotWeightTrait, Geometry, GeometryLabel, GetPos, SegWeightTrait,
 };
 use crate::layout::{
     bend::{FixedBendIndex, LooseBendIndex, LooseBendWeight},
@@ -188,7 +188,7 @@ impl Layout {
             .unwrap();
 
         self.remove_from_rtree(weight.retag(node.node_index()));
-        self.geometry.graph.remove_node(node.node_index());
+        self.geometry.remove(node);
     }
 
     // TODO: This method shouldn't be public.
@@ -729,12 +729,6 @@ impl Layout {
             .add_bend(from.into(), to.into(), core.into(), weight);
         self.geometry.reattach_bend(bend.into(), Some(inner));
 
-        self.geometry.graph.update_edge(
-            inner.node_index(),
-            bend.node_index(),
-            GeometryLabel::Outer,
-        );
-
         self.insert_into_rtree(bend.into());
         self.fail_and_remove_if_infringes_except(bend.into(), infringables)?;
         Ok(bend)
@@ -744,15 +738,7 @@ impl Layout {
     #[debug_ensures(self.geometry.graph().edge_count() == old(self.geometry.graph().edge_count()))]
     pub fn flip_bend(&mut self, bend: FixedBendIndex) {
         self.remove_from_rtree(bend.into());
-
+        self.geometry.flip_bend(bend.into());
-        let Some(GeometryWeight::FixedBend(weight)) =
-            self.geometry.graph.node_weight_mut(bend.node_index())
-        else {
-            unreachable!();
-        };
-
-        weight.cw = !weight.cw;
-
         self.insert_into_rtree(bend.into());
     }
 
@@ -821,32 +807,12 @@ impl Layout {
     ) -> Result<(), Infringement> {
         self.remove_from_rtree_with_limbs(dot.into());
 
-        let mut weight = *self.geometry.graph.node_weight(dot.node_index()).unwrap();
+        let old_pos = self.geometry.dot_weight(dot).pos();
-        let old_weight = weight;
+        self.geometry.move_dot(dot, to);
-
-        match weight {
-            GeometryWeight::FixedDot(ref mut fixed) => {
-                fixed.circle.pos = to;
-            }
-            GeometryWeight::LooseDot(ref mut loose) => {
-                loose.circle.pos = to;
-            }
-            _ => unreachable!(),
-        }
-
-        *self
-            .geometry
-            .graph
-            .node_weight_mut(dot.node_index())
-            .unwrap() = weight;
 
         if let Some(infringement) = self.detect_infringement_except(dot.into(), infringables) {
             // Restore original state.
-            *self
+            self.geometry.move_dot(dot, old_pos);
-                .geometry
-                .graph
-                .node_weight_mut(dot.node_index())
-                .unwrap() = old_weight;
 
             self.insert_into_rtree_with_limbs(dot.into());
             return Err(infringement);