router: improve error handling -- more error types, remove some unwraps

src/autorouter/autorouter.rs

@@ -22,7 +22,7 @@ use crate::{
         rules::RulesTrait,
     },
     layout::{Layout, NodeIndex},
-    router::{navmesh::Navmesh, Router, RouterObserverTrait, RoutingError},
+    router::{navmesh::Navmesh, Router, RouterError, RouterObserverTrait},
     triangulation::GetVertexIndex,
 };
 
@@ -73,12 +73,12 @@ impl Autoroute {
             (None, None)
         };
 
-        let router = Router::new_from_navmesh(
+        let mut router = Router::new_from_navmesh(
             &mut autorouter.layout,
             std::mem::replace(&mut self.navmesh, new_navmesh).unwrap(),
         );
 
-        let Ok(band) = router.unwrap().route_band(100.0, observer) else {
+        let Ok(band) = router.route_band(100.0, observer) else {
             return false;
         };
 

src/router/astar.rs

@@ -11,6 +11,7 @@ use std::hash::Hash;
 
 use petgraph::algo::Measure;
 use petgraph::visit::{EdgeRef, GraphBase, IntoEdges};
+use thiserror::Error;
 
 use std::cmp::Ordering;
 
@@ -105,7 +106,7 @@ where
     fn estimate_cost(&mut self, node: G::NodeId) -> K;
 }
 
-struct Astar<G, K>
+pub struct Astar<G, K>
 where
     G: IntoEdges,
     G::NodeId: Eq + Hash,
@@ -118,15 +119,21 @@ where
     pub path_tracker: PathTracker<G>,
 }
 
-enum AstarStatus<G, K, R>
+#[derive(Error, Debug, Clone)]
+pub enum AstarError {
+    #[error("A* search found no path")]
+    NotFound,
+}
+
+pub enum AstarStatus<G, K, R>
 where
     G: IntoEdges,
     G::NodeId: Eq + Hash,
     K: Measure + Copy,
 {
     Running,
-    Success(K, Vec<G::NodeId>, R),
-    Failure,
+    Finished(K, Vec<G::NodeId>, R),
+    Error(AstarError),
 }
 
 impl<G, K> Astar<G, K>
@@ -153,13 +160,13 @@ where
 
     pub fn step<R>(&mut self, strategy: &mut impl AstarStrategy<G, K, R>) -> AstarStatus<G, K, R> {
         let Some(MinScored(estimate_score, node)) = self.visit_next.pop() else {
-            return AstarStatus::Failure;
+            return AstarStatus::Error(AstarError::NotFound);
         };
 
         if let Some(result) = strategy.is_goal(node, &self.path_tracker) {
             let path = self.path_tracker.reconstruct_path_to(node);
             let cost = self.scores[&node];
-            return AstarStatus::Success(cost, path, result);
+            return AstarStatus::Finished(cost, path, result);
         }
 
         // This lookup can be unwrapped without fear of panic since the node was
@@ -213,7 +220,7 @@ pub fn astar<G, K, R>(
     graph: G,
     start: G::NodeId,
     strategy: &mut impl AstarStrategy<G, K, R>,
-) -> Option<(K, Vec<G::NodeId>, R)>
+) -> Result<(K, Vec<G::NodeId>, R), AstarError>
 where
     G: IntoEdges,
     G::NodeId: Eq + Hash,
@@ -221,9 +228,17 @@ where
 {
     let mut astar = Astar::new(graph, start, strategy);
 
-    while let AstarStatus::Running = astar.step(strategy) {
-        //
-    }
+    loop {
+        let status = astar.step(strategy);
 
-    None
+        /*if !matches!(status, AstarStatus::Running) {
+            return status;
+        }*/
+
+        match status {
+            AstarStatus::Running => (),
+            AstarStatus::Finished(cost, path, band) => return Ok((cost, path, band)),
+            AstarStatus::Error(err) => return Err(err),
+        }
+    }
 }

src/router/navmesh.rs

@@ -6,6 +6,7 @@ use itertools::Itertools;
 use petgraph::visit::{self, NodeIndexable};
 use petgraph::{stable_graph::NodeIndex, visit::EdgeRef};
 use spade::{HasPosition, InsertionError, Point2};
+use thiserror::Error;
 
 use crate::drawing::graph::{GetLayer, GetMaybeNet};
 use crate::geometry::shape::ShapeTrait;
@@ -85,12 +86,18 @@ pub struct Navmesh {
     to: FixedDotIndex,
 }
 
+#[derive(Error, Debug, Clone)]
+pub enum NavmeshError {
+    #[error("failed to insert vertex in navmesh")]
+    Insertion(#[from] InsertionError),
+}
+
 impl Navmesh {
     pub fn new(
         layout: &Layout<impl RulesTrait>,
         from: FixedDotIndex,
         to: FixedDotIndex,
-    ) -> Result<Self, InsertionError> {
+    ) -> Result<Self, NavmeshError> {
         let mut this = Self {
             triangulation: Triangulation::new(layout.drawing().geometry().graph().node_bound()),
             vertex_to_triangulation_vertex: Vec::new(),

src/router/router.rs

@@ -6,31 +6,28 @@ use petgraph::visit::EdgeRef;
 use spade::InsertionError;
 use thiserror::Error;
 
-use crate::drawing::band::BandIndex;
-use crate::drawing::graph::{GetLayer, GetMaybeNet};
-use crate::drawing::guide::HeadTrait;
-use crate::geometry::primitive::PrimitiveShapeTrait;
-use crate::layout::Layout;
 use crate::{
     drawing::{
+        band::BandIndex,
         dot::FixedDotIndex,
         graph::{MakePrimitive, PrimitiveIndex},
+        guide::HeadTrait,
         primitive::MakePrimitiveShape,
         rules::RulesTrait,
     },
     geometry::shape::ShapeTrait,
+    layout::Layout,
+    router::{
+        astar::{astar, AstarError, AstarStrategy, PathTracker},
+        draw::DrawException,
+        navmesh::{Navmesh, NavmeshEdgeReference, NavmeshError, VertexIndex},
+        tracer::{Trace, Tracer},
+    },
 };
 
-use crate::router::{
-    astar::{astar, AstarStrategy, PathTracker},
-    draw::DrawException,
-    navmesh::{Navmesh, NavmeshEdgeReference, VertexIndex},
-    tracer::{Trace, Tracer},
-};
-
-#[derive(Error, Debug, Clone, Copy)]
+/*#[derive(Error, Debug, Clone, Copy)]
 #[error("failed to route from {from:?} to {to:?}")] // this should eventually use Display
-pub struct RoutingError {
+pub struct RouterError {
     from: FixedDotIndex,
     to: FixedDotIndex,
     source: RoutingErrorKind,
@@ -44,6 +41,13 @@ pub enum RoutingErrorKind {
     // TODO more descriptive message
     #[error("A* found no path")]
     AStar,
+}*/
+
+#[derive(Error, Debug, Clone)]
+#[error("routing failed")]
+pub enum RouterError {
+    Navmesh(#[from] NavmeshError),
+    Astar(#[from] AstarError),
 }
 
 pub trait RouterObserverTrait<R: RulesTrait> {
@@ -169,26 +173,23 @@ impl<'a, R: RulesTrait> Router<'a, R> {
         layout: &'a mut Arc<Mutex<Layout<R>>>,
         from: FixedDotIndex,
         to: FixedDotIndex,
-    ) -> Result<Self, InsertionError> {
+    ) -> Result<Self, RouterError> {
         let navmesh = {
             let layout = layout.lock().unwrap();
             Navmesh::new(&layout, from, to)?
         };
-        Self::new_from_navmesh(layout, navmesh)
+        Ok(Self::new_from_navmesh(layout, navmesh))
     }
 
-    pub fn new_from_navmesh(
-        layout: &'a mut Arc<Mutex<Layout<R>>>,
-        navmesh: Navmesh,
-    ) -> Result<Self, InsertionError> {
-        Ok(Self { layout, navmesh })
+    pub fn new_from_navmesh(layout: &'a mut Arc<Mutex<Layout<R>>>, navmesh: Navmesh) -> Self {
+        Self { layout, navmesh }
     }
 
     pub fn route_band(
         &mut self,
         width: f64,
         observer: &mut impl RouterObserverTrait<R>,
-    ) -> Result<BandIndex, RoutingError> {
+    ) -> Result<BandIndex, RouterError> {
         let mut tracer = self.tracer();
         let trace = tracer.start(self.navmesh.from(), width);
 
@@ -196,12 +197,7 @@ impl<'a, R: RulesTrait> Router<'a, R> {
             &self.navmesh,
             self.navmesh.from().into(),
             &mut RouterAstarStrategy::new(tracer, trace, self.navmesh.to(), observer),
-        )
-        .ok_or(RoutingError {
-            from: self.navmesh.from(),
-            to: self.navmesh.to(),
-            source: RoutingErrorKind::AStar,
-        })?;
+        )?;
 
         Ok(band)
     }