From c2cd565a9b1f0478a5474affcaefaa35c4bbda05 Mon Sep 17 00:00:00 2001
From: Mikolaj Wielgus <wielgusmikolaj@gmail.com>
Date: Tue, 2 Sep 2025 22:32:49 +0200
Subject: [PATCH] refactor(drawing/gear): Remove `GetPrevNextInChain` trait

It wasn't helpful after all.
---
 src/drawing/gear.rs      | 23 -----------------------
 src/drawing/primitive.rs | 31 -------------------------------
 2 files changed, 54 deletions(-)

diff --git a/src/drawing/gear.rs b/src/drawing/gear.rs
index f1eaafb..9b755d7 100644
--- a/src/drawing/gear.rs
+++ b/src/drawing/gear.rs
@@ -83,29 +83,6 @@ pub trait WalkOutwards {
     fn outwards(&self) -> DrawingOutwardWalker;
 }
 
-//#[enum_dispatch]
-pub trait GetPrevNextInChain {
-    fn next_in_chain(&self, maybe_prev: Option<GearIndex>) -> Option<GearIndex>;
-
-    fn prev_in_chain(&self, maybe_next: Option<GearIndex>) -> Option<GearIndex> {
-        // Just as in the `GetPrevNextLoose` trait.
-        let maybe_prev = maybe_next.or_else(|| self.next_in_chain(None));
-        self.next_in_chain(maybe_prev)
-    }
-}
-
-// Because types have trait bounds, we cannot use enum_dispatch and instead we
-// implement `GetPrevNextInChain` explicitly.
-impl<'a, CW: Clone, Cel: Copy, R: AccessRules> GetPrevNextInChain for GearRef<'a, CW, Cel, R> {
-    fn next_in_chain(&self, maybe_prev: Option<GearIndex>) -> Option<GearIndex> {
-        match self {
-            GearRef::FixedDot(dot) => dot.next_in_chain(maybe_prev),
-            GearRef::FixedBend(bend) => bend.next_in_chain(maybe_prev),
-            GearRef::LooseBend(bend) => bend.next_in_chain(maybe_prev),
-        }
-    }
-}
-
 /// I found it easier to just duplicate `OutwardWalker<BI>` for `Drawing<...>`.
 pub struct DrawingOutwardWalker {
     frontier: VecDeque<LooseBendIndex>,
diff --git a/src/drawing/primitive.rs b/src/drawing/primitive.rs
index 93d8d6c..4d7f79f 100644
--- a/src/drawing/primitive.rs
+++ b/src/drawing/primitive.rs
@@ -9,7 +9,6 @@ use crate::{
     drawing::{
         bend::{BendIndex, FixedBendWeight, LooseBendIndex, LooseBendWeight},
         dot::{DotIndex, DotWeight, FixedDotIndex, FixedDotWeight, LooseDotIndex, LooseDotWeight},
-        gear::{GearIndex, GetPrevNextInChain},
         graph::{GetMaybeNet, PrimitiveIndex, PrimitiveWeight},
         rules::{AccessRules, Conditions, GetConditions},
         seg::{FixedSegWeight, LoneLooseSegWeight, SegIndex, SeqLooseSegIndex, SeqLooseSegWeight},
@@ -292,24 +291,6 @@ impl<CW, Cel, R> GetOuterGears for FixedDot<'_, CW, Cel, R> {
     }
 }
 
-impl<CW: Clone, Cel: Copy, R: AccessRules> GetPrevNextInChain for FixedDot<'_, CW, Cel, R> {
-    fn next_in_chain(&self, maybe_prev: Option<GearIndex>) -> Option<GearIndex> {
-        self.drawing
-            .overlapees(self.index.into())
-            .find_map(|infringement| {
-                let PrimitiveIndex::FixedDot(intersectee) = infringement.1 else {
-                    return None;
-                };
-
-                if let Some(prev) = maybe_prev {
-                    (infringement.1 == prev.into()).then_some(intersectee.into())
-                } else {
-                    Some(intersectee.into())
-                }
-            })
-    }
-}
-
 impl<CW, Cel, R> WalkOutwards for FixedDot<'_, CW, Cel, R> {
     fn outwards(&self) -> DrawingOutwardWalker {
         DrawingOutwardWalker::new(self.lowest_gears().into_iter())
@@ -476,12 +457,6 @@ impl<CW, Cel, R> GetOuterGears for FixedBend<'_, CW, Cel, R> {
     }
 }
 
-impl<CW, Cel, R> GetPrevNextInChain for FixedBend<'_, CW, Cel, R> {
-    fn next_in_chain(&self, _maybe_prev: Option<GearIndex>) -> Option<GearIndex> {
-        None
-    }
-}
-
 impl<CW, Cel, R> WalkOutwards for FixedBend<'_, CW, Cel, R> {
     fn outwards(&self) -> DrawingOutwardWalker {
         DrawingOutwardWalker::new(self.lowest_gears().into_iter())
@@ -535,12 +510,6 @@ impl<CW, Cel, R> GetOuterGears for LooseBend<'_, CW, Cel, R> {
     }
 }
 
-impl<CW, Cel, R> GetPrevNextInChain for LooseBend<'_, CW, Cel, R> {
-    fn next_in_chain(&self, _maybe_prev: Option<GearIndex>) -> Option<GearIndex> {
-        None
-    }
-}
-
 impl<CW, Cel, R> WalkOutwards for LooseBend<'_, CW, Cel, R> {
     fn outwards(&self) -> DrawingOutwardWalker {
         DrawingOutwardWalker::new(self.outers())