fix: unify station clicks, improve detour accuracy and UX

[GeiserX]

Summary

• Map station clicks now trigger station-leg preview — previously only sidebar list clicks did this, map clicks only highlighted. Now both use the same useEffect path that watches selectedStationId changes.
• Detour baseline accuracy — flags results where detourDuration - baselineDuration < -60s as failed (-1) instead of silently clamping to 0. Also includes the intermediate waypoint fix (already on main) that pins the baseline to the actual highway.
• Station-leg errors visible — failed station-leg previews now show a transient amber toast (3s auto-dismiss) instead of being silently hidden when base routes exist.
• Consistent route metrics — the alternatives block now uses displayRoutes[0] for the selected route during station-leg preview, matching the header metrics.
• Detour streaming decoupled from currency — effect depends on a stable stationKey (sorted station IDs) instead of the full primaryStations collection, so currency/rate changes no longer blow away in-progress detour calculations.

Test plan

• Click a station on the map → station-leg preview route appears + duration updates
• Click a station in the sidebar list → same behavior as before
• Deselect station → preview clears, base route restores
• Trigger a station-leg route failure (e.g. station in unreachable area) → amber toast appears for 3s
• During station-leg preview, verify alternatives block shows preview distance/duration for the selected route
• Switch currency while detours are loading → detours continue without restarting
• Route with distant stations (25km corridor) → detour values should not show 0 for clearly non-zero detours

Summary by CodeRabbit

• Bug Fixes

  • Improved detour time handling for negative and outlier deltas, avoiding misleading zeroed values
  • Prevented unnecessary route recalculations when station data reference changes without ID changes
  • Clearing station-preview state on request aborts/errors

• Improvements

  • Auto-clears transient route errors after a short timeout
  • More accurate route metrics display when selecting alternative routes

• New Features

  • Auto-triggered station-leg preview logic with a brief amber toast for station-related errors

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: 8c502a26-e8a9-437a-82e5-8ddb4454366f

📥 Commits

Reviewing files that changed from the base of the PR and between ee803de and 35c3323.

📒 Files selected for processing (1)

• src/components/home-client.tsx

🚧 Files skipped from review as they are similar to previous changes (1)

• src/components/home-client.tsx

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📝 Walkthrough

Walkthrough

Changed detour delta handling to compute a signed raw delta and reject large negative deltas; stabilized primary-stations referencing to avoid redundant detour recomputation; added auto-triggered station-leg logic with transient error toast and adjusted route-row metric selection.

Changes

Cohort / File(s)	Summary
Detour Calculation src/app/api/route-detour/route.ts	Replace clamped delta (Math.max(0, detour−baseline)) with raw signed delta; return { id, detourMin: -1 } when delta < −60s; otherwise compute detour minutes using clamped non-negative seconds before rounding.
Client: Station-leg & Detour Trigger src/components/home-client.tsx	Use memoized stationKey and primaryStationsRef to avoid effect reruns on reference-only changes; switch detour eligibility to read from primaryStationsRef.current; clear selectedStationId on abort/error/empty-route and when cancelling preview.
Search Panel: Auto-trigger & Error UI src/components/search/search-panel.tsx	Add transient stationLegError with auto-clear; introduce ref-backed auto-trigger (handleStationLegRef, primaryStationsRef, prevSelectedRef) to invoke station-leg when selectedStationId changes; show amber toast for station-leg errors; remove direct handleStationLeg call from station list button; adjust route-row metrics to prefer displayRoutes?.[0] when selected.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Possibly related PRs

• GeiserX/Pumperly PR 21 — related detour calculation and per-station result handling changes in the route-detour endpoint.
• GeiserX/Pumperly PR 17 — changes to baseline/delta computation for detours overlapping this endpoint’s logic.
• GeiserX/Pumperly PR 16 — modifications to detour exit/rejoin and baseline/detour duration calculations that touch the same API logic.

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 25.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately captures the main changes: unifying station click handling, improving detour accuracy calculation, and enhancing UX with error visibility and consistent metrics.

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✨ Finishing Touches

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• Commit unit tests in branch fix/station-click-and-detour-improvements

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[coderabbitai]

🧹 Nitpick comments (1)

src/components/search/search-panel.tsx (1)

419-433: Auto-trigger logic is sound.

The prevSelectedRef comparison prevents spurious triggers when other deps change. Ref-based handler/data access avoids stale closures.

Minor: Line 430 station.properties.brand ?? station.properties.name could be undefined if both are nullish, resulting in "undefined" displayed in the waypoint label. Consider a fallback:

-      station.properties.brand ?? station.properties.name,
+      station.properties.brand ?? station.properties.name ?? station.properties.id,

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@src/components/search/search-panel.tsx` around lines 419 - 433, The label
fallback can still produce "undefined" when both brand and name are nullish;
update the call in the useEffect where handleStationLegRef.current is invoked
(inside the selectedStationId/phase effect) to pass a safe fallback string
instead of station.properties.brand ?? station.properties.name — for example use
station.properties.brand ?? station.properties.name ?? `Waypoint
${station.properties.id}` or a generic 'Waypoint' so the waypoint label never
ends up as "undefined"; adjust the argument passed to
handleStationLegRef.current accordingly.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@src/components/search/search-panel.tsx`:
- Around line 419-433: The label fallback can still produce "undefined" when
both brand and name are nullish; update the call in the useEffect where
handleStationLegRef.current is invoked (inside the selectedStationId/phase
effect) to pass a safe fallback string instead of station.properties.brand ??
station.properties.name — for example use station.properties.brand ??
station.properties.name ?? `Waypoint ${station.properties.id}` or a generic
'Waypoint' so the waypoint label never ends up as "undefined"; adjust the
argument passed to handleStationLegRef.current accordingly.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro

Run ID: a2ef2a12-e110-4340-9147-d872634d5d2f

📥 Commits

Reviewing files that changed from the base of the PR and between 7d893af and ee803de.

📒 Files selected for processing (3)

• src/app/api/route-detour/route.ts
• src/components/home-client.tsx
• src/components/search/search-panel.tsx