# Gas Stations Feature - Parallel Agent Execution Plan

## Overview

This document contains agent definition prompts for implementing the Gas Stations feature using parallel execution. The backend API is complete; this plan focuses on frontend implementation, backend improvements, and integration.

### Key Context
- Backend API: Fully implemented at `backend/src/features/stations/`
- Frontend: Completely missing (needs full implementation)
- Database: Schema ready, needs migration execution
- Secrets: Google Maps API key exists in `secrets/app/google-maps-api-key.txt`
- Pattern: Follow K8s-aligned runtime secrets (not build-time env vars)
- Reference: Use `frontend/src/features/vehicles/` as implementation pattern

### Investigation Summary
- Backend has 4 complete API endpoints (search, save, get saved, delete)
- Database migration ready: `001_create_stations_tables.sql`
- External integration: Google Maps Places API client implemented
- No frontend code exists yet (placeholder route only)
- No tests exist (empty directories)
- No circuit breaker or cache cleanup implemented

## Execution Phases

```
Phase 1 (Parallel - Infrastructure):
├─ Agent 1: Frontend-Secrets-Agent
└─ Agent 2: Backend-Reliability-Agent

Phase 2 (Foundation):
└─ Agent 3: Frontend-Foundation-Agent (depends on Agent 1)

Phase 3 (Parallel - Components):
├─ Agent 4: Components-Agent (depends on Agent 3)
└─ Agent 5: Map-Visualization-Agent (depends on Agent 3)

Phase 4 (Parallel - Pages):
├─ Agent 6: Desktop-Mobile-Agent (depends on Agents 4, 5)
└─ Agent 7: Integration-Agent (depends on Agents 4, 5)

Phase 5 (Testing):
└─ Agent 8: Testing-Documentation-Agent (depends on all previous)
```

---

## Agent 1: Frontend-Secrets-Agent

### Scope
Implement K8s-aligned runtime secrets pattern for frontend to load Google Maps API key from `/run/secrets/` at container startup.

### Prerequisites
- None (can start immediately)

### Responsibilities

1. **Create Frontend Config Loader Script**
   - File: `frontend/scripts/load-config.sh`
   - Reads `/run/secrets/google-maps-api-key`
   - Generates `/usr/share/nginx/html/config.js` with: `window.CONFIG = { googleMapsApiKey: 'KEY_VALUE' }`
   - Fallback to empty string if secret not found
   - Logs success/failure for debugging

2. **Update Frontend Dockerfile**
   - File: `frontend/Dockerfile`
   - Copy `scripts/load-config.sh` into image
   - Make script executable
   - Add `SECRETS_DIR` environment variable (default: `/run/secrets`)
   - Update CMD to: `["sh", "-c", "/app/load-config.sh && nginx -g 'daemon off;'"]`

3. **Update index.html**
   - File: `frontend/index.html`
   - Add `<script src="/config.js"></script>` before app bundle script tag
   - Ensure config loads synchronously before React initializes

4. **Create Frontend Config Types**
   - File: `frontend/src/core/config/config.types.ts`
   - Interface: `RuntimeConfig { googleMapsApiKey: string }`
   - Extend Window interface: `declare global { interface Window { CONFIG: RuntimeConfig } }`
   - Export typed accessor: `export function getConfig(): RuntimeConfig`
   - Runtime validation: throw if required values missing

5. **Update docker-compose.yml**
   - File: `docker-compose.yml`
   - Add to `mvp-frontend` service volumes:
     ```yaml
     - ./secrets/app/google-maps-api-key.txt:/run/secrets/google-maps-api-key:ro
     ```
   - Add environment variable: `SECRETS_DIR: /run/secrets`

6. **Create Documentation**
   - File: `frontend/docs/RUNTIME-CONFIG.md`
   - Explain runtime config pattern vs build-time
   - How to add new runtime secrets
   - K8s deployment notes
   - Local development setup

### Success Criteria
- Frontend container starts successfully
- `/usr/share/nginx/html/config.js` exists and contains API key
- `getConfig()` returns typed RuntimeConfig object
- No TypeScript errors
- Linters pass

### Handoff Notes
Provides `getConfig().googleMapsApiKey` for Agent 5 (Map-Visualization-Agent) to use when loading Google Maps JavaScript API.

---

## Agent 2: Backend-Reliability-Agent

### Scope
Enhance backend reliability with circuit breaker, comprehensive tests, and cache cleanup job.

### Prerequisites
- None (can start immediately)

### Responsibilities

1. **Add Circuit Breaker Pattern**
   - Install package: Add `"opossum": "^8.1.4"` to `backend/package.json`
   - File: `backend/src/features/stations/external/google-maps/google-maps.circuit-breaker.ts`
   - Create circuit breaker factory function
   - Configuration: 10s timeout, 50% error threshold, 30s reset timeout
   - Update: `backend/src/features/stations/external/google-maps/google-maps.client.ts`
   - Wrap `searchNearby()` method with circuit breaker
   - Follow pattern from `backend/src/features/platform/` (reference implementation)
   - Add circuit breaker events logging (open, close, halfOpen)

2. **Backend Unit Tests**
   - File: `backend/src/features/stations/tests/unit/stations.service.test.ts`
     - Test searchStations() with valid coordinates
     - Test saveStation() with user_id isolation
     - Test getSavedStations() returns only user's stations
     - Test deleteSavedStation() removes correct station
   - File: `backend/src/features/stations/tests/unit/stations.repository.test.ts`
     - Test database queries with mock connection
     - Test SQL injection protection
     - Test constraint violations (duplicate saves)
   - File: `backend/src/features/stations/tests/unit/google-maps.client.test.ts`
     - Mock Google Maps API responses
     - Test distance calculation (Haversine formula)
     - Test photo URL generation
     - Test error handling

3. **Backend Integration Tests**
   - File: `backend/src/features/stations/tests/integration/stations.api.test.ts`
     - Test all 4 endpoints with real database
     - Test JWT authentication requirement
     - Test request validation (Zod schemas)
     - Test error responses (400, 401, 500)
   - File: `backend/src/features/stations/tests/integration/saved-stations.flow.test.ts`
     - Test complete workflow: search → save → retrieve → delete
     - Test duplicate save handling
     - Test user isolation (user A can't see user B's stations)

4. **Test Fixtures**
   - File: `backend/src/features/stations/tests/fixtures/mock-stations.ts`
     - Export sample Station objects (5-10 examples)
     - Include various ratings, distances, prices
   - File: `backend/src/features/stations/tests/fixtures/mock-google-response.ts`
     - Mock Google Places API responses
     - Include success and error cases
   - File: `backend/src/features/stations/tests/fixtures/test-coordinates.ts`
     - Sample coordinates for major cities
     - Edge cases (equator, poles, date line)

5. **Cache Cleanup Job**
   - File: `backend/src/features/stations/jobs/cache-cleanup.job.ts`
     - Scheduled job using cron (daily at 2 AM)
     - Delete `station_cache` entries older than 24 hours
     - Log metrics: rows deleted, execution time
     - Error handling and retry logic
   - Update: `backend/src/app.ts`
     - Import and register cache cleanup job
     - Add to scheduler (if exists) or create simple interval

6. **Run Tests**
   - Execute: `cd backend && npm test -- features/stations`
   - Verify 100% pass rate
   - Check coverage (aim for >80%)

### Success Criteria
- Circuit breaker implemented and tested
- All unit tests pass
- All integration tests pass
- Test coverage >80%
- Cache cleanup job registered
- Linters pass
- No TypeScript errors

### Handoff Notes
Backend is now production-ready with reliability patterns. Tests provide safety net for future changes.

---

## Agent 3: Frontend-Foundation-Agent

### Scope
Create frontend foundation: types, API client, and React Query hooks for stations feature.

### Prerequisites
- **Depends on Agent 1** (needs `getConfig()` function)

### Responsibilities

1. **Type Definitions**
   - File: `frontend/src/features/stations/types/stations.types.ts`
   - Interface `Station`:
     - placeId: string
     - name: string
     - address: string
     - location: { latitude: number; longitude: number }
     - rating?: number
     - distance: number (meters)
     - photoUrl?: string
     - prices?: { fuel_type: string; price: number }[]
   - Interface `SavedStation` extends Station:
     - userId: string
     - nickname?: string
     - notes?: string
     - isFavorite: boolean
     - savedAt: string
   - Interface `SearchRequest`:
     - latitude: number
     - longitude: number
     - radius?: number (meters, default 5000)
     - fuelType?: string
   - Interface `SearchResponse`:
     - stations: Station[]
     - searchLocation: { latitude: number; longitude: number }
   - Interface `SaveStationData`:
     - placeId: string
     - nickname?: string
     - notes?: string
     - isFavorite?: boolean

2. **API Client**
   - File: `frontend/src/features/stations/api/stations.api.ts`
   - Function `searchStations(request: SearchRequest): Promise<Station[]>`
     - POST /api/stations/search
     - Include JWT in Authorization header
     - Return stations array
   - Function `saveStation(data: SaveStationData): Promise<SavedStation>`
     - POST /api/stations/save
     - Include JWT in Authorization header
     - Return saved station with full details
   - Function `getSavedStations(): Promise<SavedStation[]>`
     - GET /api/stations/saved
     - Include JWT in Authorization header
     - Return array of user's saved stations
   - Function `deleteSavedStation(placeId: string): Promise<void>`
     - DELETE /api/stations/saved/:placeId
     - Include JWT in Authorization header
     - Return nothing (204 No Content)
   - Use axios instance from `frontend/src/core/api/client.ts`
   - Proper error handling with try-catch
   - Add request/response logging for debugging

3. **React Query Hooks**
   - File: `frontend/src/features/stations/hooks/useStationsSearch.ts`
     - Export `useStationsSearch()` mutation hook
     - Accepts SearchRequest, returns Station[]
     - Don't cache by default (location-specific queries)
     - Loading/error states
   - File: `frontend/src/features/stations/hooks/useSavedStations.ts`
     - Export `useSavedStations()` query hook
     - Query key: `['stations', 'saved']`
     - Auto-refetch on window focus
     - Stale time: 5 minutes
     - Loading/error states
   - File: `frontend/src/features/stations/hooks/useSaveStation.ts`
     - Export `useSaveStation()` mutation hook
     - Accepts SaveStationData
     - Optimistic update: add to saved list immediately
     - On success: invalidate `['stations', 'saved']` query
     - On error: rollback optimistic update
   - File: `frontend/src/features/stations/hooks/useDeleteStation.ts`
     - Export `useDeleteStation()` mutation hook
     - Accepts placeId string
     - Optimistic update: remove from saved list
     - On success: invalidate `['stations', 'saved']` query
     - On error: rollback optimistic update
   - File: `frontend/src/features/stations/hooks/useGeolocation.ts`
     - Export `useGeolocation()` hook
     - Uses browser Geolocation API
     - Returns: `{ position, loading, error, requestLocation }`
     - Handle permission states: prompt, granted, denied
     - Error handling: timeout, unavailable, permission denied
     - Options: enableHighAccuracy, timeout, maximumAge

4. **Utilities**
   - File: `frontend/src/features/stations/utils/distance.ts`
     - Export `formatDistance(meters: number): string`
     - Convert meters to miles with proper formatting
     - Examples: "0.3 mi", "1.2 mi", "5.7 mi"
   - File: `frontend/src/features/stations/utils/location.ts`
     - Export `getCurrentPosition(): Promise<GeolocationPosition>`
     - Wrapper around navigator.geolocation.getCurrentPosition
     - Promisified API
     - Error handling helpers

### Success Criteria
- All type interfaces defined with proper TypeScript types
- API client functions work (test with curl against backend)
- All React Query hooks created with proper caching
- Geolocation hook handles all permission states
- No TypeScript errors
- Linters pass
- Utilities properly format data

### Handoff Notes
Foundation is complete. Agent 4 and Agent 5 can now build components and map visualization using these types, API client, and hooks.

---

## Agent 4: Components-Agent

### Scope
Build all React components for stations feature (cards, lists, forms).

### Prerequisites
- **Depends on Agent 3** (needs types, hooks, API client)

### Responsibilities

1. **StationCard Component**
   - File: `frontend/src/features/stations/components/StationCard.tsx`
   - Props:
     - station: Station
     - isSaved?: boolean
     - onSave?: (placeId: string) => void
     - onDelete?: (placeId: string) => void
     - onSelect?: (station: Station) => void
   - UI Elements:
     - Material-UI Card component
     - Station name (Typography variant="h6")
     - Address (Typography variant="body2", color="text.secondary")
     - Distance chip (Chip with LocationOnIcon)
     - Rating stars (Rating component, if rating exists)
     - Price display (Typography, if prices available)
     - Photo thumbnail (CardMedia, if photoUrl exists)
     - Save/Unsave IconButton (BookmarkIcon / BookmarkBorderIcon)
     - Directions link (Button with OpenInNewIcon, opens Google Maps)
   - Styling:
     - Responsive: full width on mobile, fixed width on desktop
     - Min height 44px for touch targets
     - Hover effects on desktop
     - Loading state while saving/deleting
   - Follow pattern: `frontend/src/features/vehicles/components/VehicleCard.tsx`

2. **StationsList Component**
   - File: `frontend/src/features/stations/components/StationsList.tsx`
   - Props:
     - stations: Station[]
     - loading?: boolean
     - error?: Error | null
     - onSaveStation?: (placeId: string) => void
     - savedStationIds?: Set<string>
   - UI Elements:
     - Grid container (responsive)
     - Layout: 1 col mobile, 2 cols tablet, 3 cols desktop
     - Loading state: Skeleton components (3-6 skeletons)
     - Empty state: "No stations found. Try adjusting your search."
     - Error state: Alert with retry option
     - Map stations to StationCard components
   - Styling:
     - Gap between cards: 16px
     - Smooth loading transitions
   - Follow pattern: `frontend/src/features/vehicles/components/VehiclesList.tsx`

3. **SavedStationsList Component**
   - File: `frontend/src/features/stations/components/SavedStationsList.tsx`
   - Props:
     - savedStations: SavedStation[]
     - loading?: boolean
     - error?: Error | null
     - onDelete: (placeId: string) => void
     - onSelect?: (station: SavedStation) => void
     - currentLocation?: { latitude: number; longitude: number }
   - UI Elements:
     - List container (vertical)
     - Each item shows: nickname || name, address, distance from current location
     - Notes preview (truncated to 50 chars)
     - Favorite icon if isFavorite
     - Delete IconButton with confirmation dialog
     - Loading state: Linear progress bar
     - Empty state: "No saved stations yet. Save stations from search results."
     - Error state: Alert with error message
   - Styling:
     - List item min height: 64px
     - Dividers between items
     - Delete button always visible (not just on hover for mobile)
   - Follow pattern: Material-UI List component examples

4. **StationsSearchForm Component**
   - File: `frontend/src/features/stations/components/StationsSearchForm.tsx`
   - Props:
     - onSearch: (request: SearchRequest) => void
     - loading?: boolean
   - UI Elements:
     - Form container (Card or Paper)
     - "Use Current Location" Button (uses useGeolocation hook)
     - OR divider
     - Manual lat/lng inputs (TextField type="number")
     - Radius slider (Slider: 1-25 miles, default 5, step 1)
     - Fuel type select (optional, Select component)
     - Search LoadingButton (shows loading state during search)
     - Geolocation status indicator (permission state)
     - Error display for geolocation failures
   - Validation:
     - Require either current location OR manual lat/lng
     - Validate latitude: -90 to 90
     - Validate longitude: -180 to 180
   - Behavior:
     - Click "Use Current Location" → request permission → populate hidden lat/lng
     - Manual input disables current location
     - Convert miles to meters for API (1 mile = 1609.34 meters)
   - Styling:
     - Compact form layout
     - Responsive: stack vertically on mobile
     - Clear visual feedback for loading states
   - Follow pattern: `frontend/src/features/fuel-logs/components/FuelLogForm.tsx`

5. **Create Feature Index**
   - File: `frontend/src/features/stations/components/index.ts`
   - Export all components for easy importing

### Success Criteria
- All 4 components render without errors
- Components follow Material-UI design patterns
- Mobile responsive (test at 375px width)
- Touch targets minimum 44px
- Loading and error states work
- TypeScript types are correct
- Linters pass
- Components match vehicles feature pattern

### Handoff Notes
Core components are ready. Agent 6 can now build pages using these components. Agent 7 can integrate with map visualization.

---

## Agent 5: Map-Visualization-Agent

### Scope
Implement Google Maps integration and StationMap component for visualizing stations on a map.

### Prerequisites
- **Depends on Agent 1** (needs `getConfig().googleMapsApiKey`)
- **Depends on Agent 3** (needs Station types)

### Responsibilities

1. **Google Maps API Loader**
   - File: `frontend/src/features/stations/utils/maps-loader.ts`
   - Function: `loadGoogleMapsAPI(): Promise<typeof google>`
   - Load Google Maps JavaScript API dynamically
   - Use runtime config: `getConfig().googleMapsApiKey`
   - Include libraries: `libraries=places,geometry`
   - Singleton pattern: only load once, return cached promise
   - Error handling: throw if API key missing or script fails
   - TypeScript: Use `@types/google.maps` for types

2. **Map Utilities**
   - File: `frontend/src/features/stations/utils/map-utils.ts`
   - Function: `createStationMarker(station: Station, map: google.maps.Map, isSaved: boolean): google.maps.Marker`
     - Create marker at station location
     - Icon: blue pin for normal, gold star for saved
     - Title: station name
     - Clickable: true
   - Function: `createInfoWindow(station: Station, isSaved: boolean, onSave: () => void, onDirections: () => void): google.maps.InfoWindow`
     - Create info window with station details
     - Content: name, address, rating, distance
     - Action buttons: Save/Saved, Directions
     - HTML string with proper escaping
   - Function: `fitBoundsToMarkers(map: google.maps.Map, markers: google.maps.Marker[]): void`
     - Calculate bounds containing all markers
     - Fit map to bounds with padding
     - Handle single marker case (zoom to 14)
   - Function: `calculateCenter(stations: Station[]): google.maps.LatLng`
     - Calculate geometric center of stations
     - Return LatLng object

3. **StationMap Component**
   - File: `frontend/src/features/stations/components/StationMap.tsx`
   - Props:
     - stations: Station[]
     - savedStationIds?: Set<string>
     - center?: { latitude: number; longitude: number }
     - zoom?: number
     - currentLocation?: { latitude: number; longitude: number }
     - onStationClick?: (station: Station) => void
     - onSaveStation?: (placeId: string) => void
   - State:
     - map: google.maps.Map | null
     - markers: google.maps.Marker[]
     - infoWindow: google.maps.InfoWindow | null
   - Behavior:
     - Load Google Maps API on mount (useEffect)
     - Initialize map in div container
     - Create markers for all stations
     - Current location marker (red pin, if provided)
     - Click marker → open info window
     - Click save button → call onSaveStation
     - Click directions → open Google Maps in new tab
     - Auto-fit bounds to show all markers
     - Clean up markers on unmount
   - Styling:
     - Container: width 100%, height configurable (default 500px)
     - Responsive: 300px height on mobile, 500px on desktop
     - Map controls: zoom, pan, fullscreen
     - Custom map styles (optional: subtle styling)
   - Map Options:
     - mapTypeControl: false
     - streetViewControl: false
     - fullscreenControl: true
     - zoomControl: true
   - Error Handling:
     - Show error message if API fails to load
     - Fallback: display stations in list if map unavailable

4. **TypeScript Types**
   - Ensure `@types/google.maps` is in `frontend/package.json`
   - Add if missing: `"@types/google.maps": "^3.54.0"`

5. **Testing**
   - Test map loads with valid API key
   - Test markers render for each station
   - Test info windows open on marker click
   - Test current location marker (red pin)
   - Test directions link opens correct URL
   - Test error handling (invalid API key)

### Success Criteria
- Google Maps API loads successfully from runtime config
- StationMap component renders map
- Markers appear for all stations
- Color coding works (blue vs gold for saved)
- Info windows display correct station details
- Directions links work
- Current location marker shows if provided
- Responsive sizing works
- No TypeScript errors
- Linters pass

### Handoff Notes
Map visualization is complete. Agent 6 can integrate StationMap into desktop and mobile pages.

---

## Agent 6: Desktop-Mobile-Agent

### Scope
Build desktop StationsPage and mobile StationsMobileScreen, update routing.

### Prerequisites
- **Depends on Agent 4** (needs all components)
- **Depends on Agent 5** (needs StationMap)

### Responsibilities

1. **Desktop StationsPage**
   - File: `frontend/src/features/stations/pages/StationsPage.tsx`
   - Layout:
     - Container: Full width, Grid layout
     - Left column (60%): StationMap (full height 600px)
     - Right column (40%):
       - StationsSearchForm at top
       - Tabs component: "Search Results" | "Saved Stations"
       - Tab 1 content: StationsList (scrollable)
       - Tab 2 content: SavedStationsList (scrollable)
   - State:
     - searchResults: Station[] (from useStationsSearch)
     - selectedStation: Station | null (for map focus)
     - currentLocation: Position | null (from useGeolocation)
     - activeTab: 0 | 1
   - Hooks:
     - useStationsSearch() for searching
     - useSavedStations() for saved list
     - useSaveStation() for saving
     - useDeleteStation() for deleting
     - useGeolocation() for current location
   - Behavior:
     - On search submit → call searchStations mutation
     - On search success → update map with results
     - On save station → add to saved list (optimistic)
     - On delete station → remove from saved list (optimistic)
     - Click station card → highlight on map (zoom to marker)
     - Map marker click → highlight card and scroll into view
   - Responsive:
     - Breakpoint <960px: Stack vertically (map on top)
     - Mobile view: Map 300px height, full width
   - Loading States:
     - Show loading spinner during search
     - Skeleton loaders for saved stations
   - Error Handling:
     - Display error alerts for API failures
     - Retry buttons where appropriate
   - Follow pattern: `frontend/src/features/vehicles/pages/VehiclesPage.tsx`

2. **Mobile StationsScreen**
   - File: `frontend/src/features/stations/pages/StationsMobileScreen.tsx`
   - Layout:
     - BottomNavigation with 3 tabs: "Search", "Saved", "Map"
     - Tab content area (full screen minus bottom nav)
   - Tab 0 (Search):
     - StationsSearchForm (compact mode, vertical layout)
     - StationsList (vertical scroll, full width)
     - Pull-to-refresh support (optional)
   - Tab 1 (Saved):
     - SavedStationsList (full screen)
     - Swipe-to-delete gestures (optional enhancement)
     - Empty state with illustration
   - Tab 2 (Map):
     - StationMap (full screen, 100vh minus nav)
     - Floating action button (FAB) to return to search tab
     - Current location button (FAB)
   - State:
     - activeTab: 0 | 1 | 2
     - Same data state as desktop page
   - Hooks:
     - Same as desktop page
   - Behavior:
     - Tab switching persists scroll position
     - Search → auto-switch to results view
     - Save station → show snackbar confirmation
     - Map marker click → open bottom sheet with station details
   - Bottom Sheet:
     - SwipeableDrawer component
     - Shows station details
     - Save/Delete buttons
     - Directions link
   - Touch Targets:
     - All buttons minimum 44px
     - Adequate spacing between interactive elements
   - Safe Areas:
     - Handle notched devices (safe-area-inset)
     - Bottom navigation respects safe area
   - Follow pattern: `frontend/src/features/vehicles/pages/VehiclesMobileScreen.tsx`

3. **Update Desktop Routing**
   - File: `frontend/src/App.tsx` (around line 556)
   - Remove: `<Route path="/stations" element={<div>Stations (TODO)</div>} />`
   - Add: `<Route path="/stations" element={<StationsPage />} />`
   - Import: `import { StationsPage } from './features/stations/pages/StationsPage'`
   - Verify route is inside ProtectedRoute wrapper (requires auth)

4. **Update Mobile Routing**
   - File: `frontend/src/App.tsx` (mobile routes section)
   - Add: `<Route path="/m/stations" element={<StationsMobileScreen />} />`
   - Import: `import { StationsMobileScreen } from './features/stations/pages/StationsMobileScreen'`
   - Update mobile navigation items:
     - Add stations icon and route to bottom nav
     - Icon: PlaceRoundedIcon (already used in Layout.tsx)
     - Ensure onClick navigates to `/m/stations`

5. **Feature Index**
   - File: `frontend/src/features/stations/index.ts`
   - Export StationsPage and StationsMobileScreen
   - Export all components for external use

6. **Manual Testing**
   - Desktop: Navigate to /stations, test all functionality
   - Mobile: Navigate to /m/stations, test all tabs
   - Test on real mobile device or Chrome DevTools mobile emulation
   - Verify responsive breakpoints work
   - Verify touch targets are adequate (44px minimum)

### Success Criteria
- Desktop page renders and functions completely
- Mobile screen renders with all 3 tabs
- Routing works for both desktop and mobile
- All components integrate properly
- Search, save, delete operations work
- Map updates when data changes
- Mobile touch targets meet 44px requirement
- Responsive design works at all breakpoints
- No TypeScript errors
- Linters pass

### Handoff Notes
Desktop and mobile UIs are complete and fully functional. Users can now search, save, and view stations on both platforms.

---

## Agent 7: Integration-Agent

### Scope
Integrate stations feature with fuel logs using a station picker component.

### Prerequisites
- **Depends on Agent 4** (needs StationCard and search functionality)
- **Depends on Agent 5** (needs map utilities)

### Responsibilities

1. **StationPicker Component**
   - File: `frontend/src/features/fuel-logs/components/StationPicker.tsx`
   - Props:
     - value: string (station name)
     - onChange: (stationName: string) => void
     - userLocation?: { latitude: number; longitude: number }
     - label?: string
     - error?: boolean
     - helperText?: string
   - UI Elements:
     - Autocomplete component (Material-UI)
     - TextField with LocationOnIcon adornment
     - Dropdown shows: saved stations (group 1) + nearby stations (group 2)
     - Option rendering:
       - Primary text: station name
       - Secondary text: distance + address
       - Bookmark icon if saved
     - FreeSolo mode: allow manual text entry
     - Loading indicator while fetching stations
   - Behavior:
     - On focus → fetch saved stations immediately
     - If userLocation provided → fetch nearby stations (5 mile radius)
     - Show saved stations first (grouped, labeled "Saved Stations")
     - Show nearby stations second (grouped, labeled "Nearby Stations")
     - On select → call onChange with station name
     - On manual input → call onChange with entered text
     - Debounce: 300ms delay for search queries
   - Data:
     - Use useSavedStations() hook
     - Use useStationsSearch() hook with userLocation
     - Combine results: saved + nearby
     - De-duplicate by placeId
   - Error Handling:
     - If geolocation fails → only show saved stations
     - If API fails → fallback to manual text input
     - Display error message in helper text
   - Follow pattern: Material-UI Autocomplete with grouping

2. **Update FuelLogForm**
   - File: `frontend/src/features/fuel-logs/components/FuelLogForm.tsx`
   - Find: Current location input field (likely TextField or LocationInput component)
   - Replace with: StationPicker component
   - Props to pass:
     - value: formData.stationName (or equivalent)
     - onChange: (name) => setFormData({ ...formData, stationName: name })
     - userLocation: from useGeolocation hook
     - label: "Gas Station"
     - error: Boolean(errors.stationName)
     - helperText: errors.stationName
   - Integration:
     - Add useGeolocation hook to FuelLogForm
     - Pass current position to StationPicker
     - Maintain existing form validation
     - Ensure backward compatibility (text input still works)

3. **Enhance Fuel Log Display (Optional)**
   - File: `frontend/src/features/fuel-logs/components/FuelLogCard.tsx`
   - If stationName is present → make it clickable
   - On click → navigate to /stations with search for that name
   - OR: Show station details in dialog
   - Add LocationOnIcon next to station name
   - Follow existing card styling

4. **Add Geolocation to Fuel Logs**
   - Update FuelLogForm to request location permission on mount
   - Store current location in component state
   - Pass to StationPicker for nearby stations
   - Show permission request UI if needed
   - Handle permission denied gracefully (picker still works with saved stations)

5. **Testing**
   - Test StationPicker in isolation (render component)
   - Test selecting saved station
   - Test selecting nearby station
   - Test manual text entry (freeSolo)
   - Test integration in FuelLogForm
   - Test submitting fuel log with station
   - Test geolocation permission flow

### Success Criteria
- StationPicker component renders and functions
- Saved stations appear in dropdown
- Nearby stations appear in dropdown (if location available)
- Manual text entry works (fallback)
- FuelLogForm integrates StationPicker successfully
- Submitting fuel log with station works
- Backward compatible (existing fuel logs still display)
- Geolocation permission handled gracefully
- No TypeScript errors
- Linters pass

### Handoff Notes
Fuel logs now integrate with stations feature. Users can select stations from saved or nearby lists when logging fuel, improving data consistency and user experience.

---

## Agent 8: Testing-Documentation-Agent

### Scope
Create comprehensive tests for all new code and complete documentation.

### Prerequisites
- **Depends on all previous agents** (needs complete implementation)

### Responsibilities

1. **Backend Tests Verification**
   - Run: `cd backend && npm test -- features/stations`
   - Verify all tests pass (from Agent 2)
   - If failures: debug and fix
   - Check coverage: `npm test -- --coverage features/stations`
   - Ensure coverage >80%

2. **Frontend Component Tests**
   - File: `frontend/src/features/stations/__tests__/components/StationCard.test.tsx`
     - Test rendering with all props
     - Test save button click
     - Test delete button click
     - Test directions link
   - File: `frontend/src/features/stations/__tests__/components/StationsList.test.tsx`
     - Test rendering with stations array
     - Test loading state (skeletons)
     - Test empty state
     - Test error state
   - File: `frontend/src/features/stations/__tests__/components/SavedStationsList.test.tsx`
     - Test rendering saved stations
     - Test delete action
     - Test empty state
   - File: `frontend/src/features/stations/__tests__/components/StationsSearchForm.test.tsx`
     - Test form submission
     - Test validation (lat/lng ranges)
     - Test current location button
     - Test manual input
   - File: `frontend/src/features/stations/__tests__/components/StationMap.test.tsx`
     - Mock Google Maps API
     - Test map initialization
     - Test marker rendering
     - Test info window
   - Use React Testing Library
   - Mock hooks with jest.mock()

3. **Frontend API Tests**
   - File: `frontend/src/features/stations/api/__tests__/stations.api.test.ts`
     - Test searchStations() - mock axios
     - Test saveStation() - mock axios
     - Test getSavedStations() - mock axios
     - Test deleteSavedStation() - mock axios
     - Test error handling (network errors, 401, 500)
     - Verify request payloads
     - Verify response parsing

4. **Frontend Hook Tests**
   - File: `frontend/src/features/stations/hooks/__tests__/useStationsSearch.test.ts`
     - Test mutation flow
     - Test loading state
     - Test success state
     - Test error state
   - File: `frontend/src/features/stations/hooks/__tests__/useSavedStations.test.ts`
     - Test query flow
     - Test cache behavior
     - Test refetch logic
   - File: `frontend/src/features/stations/hooks/__tests__/useSaveStation.test.ts`
     - Test mutation with optimistic update
     - Test cache invalidation
     - Test rollback on error
   - File: `frontend/src/features/stations/hooks/__tests__/useDeleteStation.test.ts`
     - Test mutation with optimistic update
     - Test cache invalidation
     - Test rollback on error
   - Use @testing-library/react-hooks
   - Mock React Query client

5. **Frontend Page Tests**
   - File: `frontend/src/features/stations/__tests__/pages/StationsPage.test.tsx`
     - Test page renders
     - Test search workflow
     - Test save station workflow
     - Test tab switching
     - Test map interaction
   - File: `frontend/src/features/stations/__tests__/pages/StationsMobileScreen.test.tsx`
     - Test all 3 tabs render
     - Test tab navigation
     - Test search on mobile
     - Test saved list on mobile

6. **Integration Component Tests**
   - File: `frontend/src/features/fuel-logs/__tests__/components/StationPicker.test.tsx`
     - Test rendering
     - Test saved stations load
     - Test nearby stations load (with geolocation)
     - Test manual text entry
     - Test selection callback
     - Mock useStationsSearch and useSavedStations

7. **E2E Tests (Optional but Recommended)**
   - File: `frontend/cypress/e2e/stations.cy.ts` (or similar framework)
   - Test flows:
     - Login → Navigate to Stations
     - Search for nearby stations
     - Save a station
     - View saved stations
     - Delete a station
     - Navigate to Fuel Logs
     - Select station from picker
     - Submit fuel log
     - Verify station name appears in log
   - Use real backend in test environment
   - Seed test data if needed

8. **Run All Tests**
   - Backend: `cd backend && npm test`
   - Frontend: `cd frontend && npm test`
   - Verify 100% pass rate
   - Fix any failures

9. **Backend Documentation**
   - File: `backend/src/features/stations/docs/ARCHITECTURE.md`
     - System design overview
     - Data flow diagrams (text-based)
     - External dependencies (Google Maps Places API)
     - Caching strategy (Redis + PostgreSQL)
     - Database schema with relationships
     - Circuit breaker pattern explanation
   - File: `backend/src/features/stations/docs/API.md`
     - All endpoint documentation
     - Request/response examples with curl commands
     - Authentication requirements (JWT)
     - Rate limits and quotas
     - Error response formats
   - File: `backend/src/features/stations/docs/TESTING.md`
     - How to run tests
     - Test database setup
     - Writing new tests
     - Coverage goals (>80%)
     - CI/CD integration
   - File: `backend/src/features/stations/docs/GOOGLE-MAPS-SETUP.md`
     - Google Cloud Console setup
     - Create project and enable Places API
     - API key creation and restrictions
     - Quota management and monitoring
     - Cost estimation ($10-50/month typical)
     - Security best practices (restrict by IP, referrer)

10. **Frontend Documentation**
    - File: `frontend/src/features/stations/README.md`
      - Feature overview
      - Component hierarchy diagram (text-based)
      - Hook usage examples
      - Adding new functionality guide
      - Runtime config pattern explanation
      - Testing guide
      - Integration with other features
    - Update: `frontend/docs/RUNTIME-CONFIG.md` (created by Agent 1)
      - Ensure complete and accurate

11. **Update Main Documentation**
    - File: `docs/README.md`
      - Add "Gas Stations" to features list
      - Brief description: "Search and save gas stations using Google Maps"
      - Link to backend docs: `backend/src/features/stations/docs/`
      - Link to frontend docs: `frontend/src/features/stations/README.md`
    - File: `backend/src/features/stations/README.md`
      - Update with complete feature overview
      - Configuration requirements
      - API endpoints summary
      - Testing instructions
      - Deployment notes

12. **Create User Guide (Optional)**
    - File: `docs/USER-GUIDE-STATIONS.md`
      - How to search for stations
      - How to save favorites
      - How to use in fuel logs
      - Screenshots (if possible)
      - Troubleshooting common issues

### Success Criteria
- All backend tests pass (100%)
- All frontend tests pass (100%)
- Test coverage >80% for new code
- All documentation files created
- Documentation is clear and accurate
- Code examples in docs work
- Main README updated
- No TypeScript errors
- Linters pass

### Handoff Notes
Testing and documentation complete. Feature is production-ready. All code is tested, documented, and follows project standards.

---

## Final Validation Checklist

After all agents complete, run final validation:

### Build & Deploy
```bash
make rebuild   # Rebuild all containers
make logs      # Watch for errors
make migrate   # Run database migrations
make test      # Run all tests
```

### Linting
```bash
cd backend && npm run lint && npm run type-check
cd frontend && npm run lint && npm run type-check
```

### Manual Testing
- [ ] Desktop: Search stations at https://motovaultpro.com/stations
- [ ] Desktop: Save a station
- [ ] Desktop: View saved stations
- [ ] Desktop: Delete a station
- [ ] Desktop: Map visualization works
- [ ] Mobile: Navigate to stations (/m/stations)
- [ ] Mobile: All 3 tabs work
- [ ] Mobile: Touch targets are 44px minimum
- [ ] Fuel Logs: Station picker works
- [ ] Fuel Logs: Submit log with station
- [ ] Cross-browser: Chrome, Safari, Firefox

### Performance
- [ ] Map loads in <2 seconds
- [ ] API responses <500ms
- [ ] Redis caching works (check logs)
- [ ] No memory leaks (React DevTools)

### Security
- [ ] All endpoints require JWT auth
- [ ] User data isolation works (can't see other users' saved stations)
- [ ] SQL injection protected (prepared statements)
- [ ] API key not exposed to client (runtime config)

### Documentation
- [ ] All docs created and accurate
- [ ] Code examples work
- [ ] Main README updated
- [ ] Google Maps setup guide complete

### Standards (per CLAUDE.md)
- [ ] All linters pass with zero issues
- [ ] All tests pass
- [ ] Feature works end-to-end on desktop
- [ ] Feature works end-to-end on mobile
- [ ] Old code deleted (no placeholder routes)
- [ ] No emojis in code or docs
- [ ] Meaningful variable names used

---

## Execution Commands

To execute agents in parallel using Claude Code:

### Phase 1 (Parallel)
```bash
# Terminal 1
claude-code "Execute Agent 1: Frontend-Secrets-Agent as defined in GAS-STATION-AGENTS.md"

# Terminal 2
claude-code "Execute Agent 2: Backend-Reliability-Agent as defined in GAS-STATION-AGENTS.md"
```

### Phase 2
```bash
# Wait for Phase 1 to complete
claude-code "Execute Agent 3: Frontend-Foundation-Agent as defined in GAS-STATION-AGENTS.md"
```

### Phase 3 (Parallel)
```bash
# Terminal 1
claude-code "Execute Agent 4: Components-Agent as defined in GAS-STATION-AGENTS.md"

# Terminal 2
claude-code "Execute Agent 5: Map-Visualization-Agent as defined in GAS-STATION-AGENTS.md"
```

### Phase 4 (Parallel)
```bash
# Terminal 1
claude-code "Execute Agent 6: Desktop-Mobile-Agent as defined in GAS-STATION-AGENTS.md"

# Terminal 2
claude-code "Execute Agent 7: Integration-Agent as defined in GAS-STATION-AGENTS.md"
```

### Phase 5
```bash
# Wait for Phase 4 to complete
claude-code "Execute Agent 8: Testing-Documentation-Agent as defined in GAS-STATION-AGENTS.md"
```

---

## Notes

- Each agent is designed to be autonomous and complete its scope independently
- Agents include clear prerequisites and dependencies
- Follow CLAUDE.md standards: no emojis, meaningful names, delete old code
- All implementations follow K8s-aligned patterns (runtime secrets, not build-time)
- Reference implementation: vehicles feature
- Testing is mandatory (per CLAUDE.md: must be 100% green)
- Mobile + Desktop requirement: all features work on both platforms

---

## Estimated Total Time

- Phase 1: 8 hours (parallel: 8 hours)
- Phase 2: 4 hours
- Phase 3: 8 hours (parallel: 8 hours)
- Phase 4: 8 hours (parallel: 8 hours)
- Phase 5: 12 hours

**Total: 40 hours elapsed (with parallelization)**
**Total: 48 hours of work (across all agents)**

**Savings from parallelization: 8 hours (17% faster)**