# Phase 4: Trefle API & Plant Care

**Goal:** Complete care information and scheduling with local notifications

**Prerequisites:** Phase 3 complete (hybrid identification working, API infrastructure established)

---

## Tasks

### 4.1 Register for Trefle API Access
- [ ] Navigate to [trefle.io](https://trefle.io)
- [ ] Create developer account
- [ ] Generate API token
- [ ] Review API documentation and rate limits
- [ ] Add `TREFLE_API_TOKEN` to `APIKeys.swift`:
  ```swift
  enum APIKeys {
      // ... existing keys

      static let trefleAPIToken: String = {
          guard let token = Bundle.main.object(forInfoDictionaryKey: "TREFLE_API_TOKEN") as? String else {
              fatalError("Trefle API token not configured")
          }
          return token
      }()
  }
  ```
- [ ] Add `TREFLE_API_TOKEN` to Info.plist via xcconfig
- [ ] Update `.xcconfig` file with Trefle token (already in .gitignore)
- [ ] Verify API access with test request

**Acceptance Criteria:** API token configured and accessible, test request returns valid data

---

### 4.2 Create Trefle Endpoints
- [ ] Create `Data/DataSources/Remote/TrefleAPI/TrefleEndpoints.swift`
- [ ] Define endpoint configuration:
  ```swift
  enum TrefleEndpoint: Endpoint {
      case searchPlants(query: String, page: Int)
      case getSpecies(slug: String)
      case getSpeciesById(id: Int)
      case getPlant(id: Int)

      var baseURL: URL { URL(string: "https://trefle.io/api/v1")! }

      var path: String {
          switch self {
          case .searchPlants: return "/plants/search"
          case .getSpecies(let slug): return "/species/\(slug)"
          case .getSpeciesById(let id): return "/species/\(id)"
          case .getPlant(let id): return "/plants/\(id)"
          }
      }

      var method: HTTPMethod { .get }

      var queryItems: [URLQueryItem] {
          var items = [URLQueryItem(name: "token", value: APIKeys.trefleAPIToken)]
          switch self {
          case .searchPlants(let query, let page):
              items.append(URLQueryItem(name: "q", value: query))
              items.append(URLQueryItem(name: "page", value: String(page)))
          default:
              break
          }
          return items
      }
  }
  ```
- [ ] Support pagination for search results
- [ ] Add filter parameters (edible, vegetable, etc.)

**Acceptance Criteria:** Endpoints build correct URLs with token and query parameters

---

### 4.3 Implement Trefle API Service
- [ ] Create `Data/DataSources/Remote/TrefleAPI/TrefleAPIService.swift`
- [ ] Define protocol:
  ```swift
  protocol TrefleAPIServiceProtocol: Sendable {
      func searchPlants(query: String, page: Int) async throws -> TrefleSearchResponseDTO
      func getSpecies(slug: String) async throws -> TrefleSpeciesResponseDTO
      func getSpeciesById(id: Int) async throws -> TrefleSpeciesResponseDTO
  }
  ```
- [ ] Implement service using NetworkService:
  - Handle token-based authentication
  - Parse paginated responses
  - Handle 404 for unknown species
- [ ] Implement retry logic (1 retry with exponential backoff)
- [ ] Add request timeout (15 seconds)
- [ ] Handle rate limiting (120 requests/minute)
- [ ] Log request/response for debugging

**Acceptance Criteria:** Service retrieves species data and handles errors gracefully

---

### 4.4 Create Trefle DTOs
- [ ] Create `Data/DataSources/Remote/TrefleAPI/DTOs/TrefleDTOs.swift`
- [ ] Define response DTOs:
  ```swift
  struct TrefleSearchResponseDTO: Decodable {
      let data: [TreflePlantSummaryDTO]
      let links: TrefleLinksDTO
      let meta: TrefleMetaDTO
  }

  struct TrefleSpeciesResponseDTO: Decodable {
      let data: TrefleSpeciesDTO
      let meta: TrefleMetaDTO
  }
  ```
- [ ] Create `TrefleSpeciesDTO`:
  ```swift
  struct TrefleSpeciesDTO: Decodable {
      let id: Int
      let commonName: String?
      let slug: String
      let scientificName: String
      let year: Int?
      let bibliography: String?
      let author: String?
      let familyCommonName: String?
      let family: String?
      let genus: String?
      let genusId: Int?
      let imageUrl: String?
      let images: TrefleImagesDTO?
      let distribution: TrefleDistributionDTO?
      let specifications: TrefleSpecificationsDTO?
      let growth: TrefleGrowthDTO?
      let synonyms: [TrefleSynonymDTO]?
      let sources: [TrefleSourceDTO]?
  }
  ```
- [ ] Create `TrefleGrowthDTO`:
  ```swift
  struct TrefleGrowthDTO: Decodable {
      let description: String?
      let sowing: String?
      let daysToHarvest: Int?
      let rowSpacing: TrefleMeasurementDTO?
      let spread: TrefleMeasurementDTO?
      let phMaximum: Double?
      let phMinimum: Double?
      let light: Int?          // 0-10 scale
      let atmosphericHumidity: Int?  // 0-10 scale
      let growthMonths: [String]?
      let bloomMonths: [String]?
      let fruitMonths: [String]?
      let minimumPrecipitation: TrefleMeasurementDTO?
      let maximumPrecipitation: TrefleMeasurementDTO?
      let minimumRootDepth: TrefleMeasurementDTO?
      let minimumTemperature: TrefleMeasurementDTO?
      let maximumTemperature: TrefleMeasurementDTO?
      let soilNutriments: Int?  // 0-10 scale
      let soilSalinity: Int?    // 0-10 scale
      let soilTexture: Int?     // 0-10 scale
      let soilHumidity: Int?    // 0-10 scale
  }
  ```
- [ ] Create supporting DTOs: `TrefleSpecificationsDTO`, `TrefleImagesDTO`, `TrefleMeasurementDTO`
- [ ] Add CodingKeys for snake_case API responses
- [ ] Write unit tests for DTO decoding

**Acceptance Criteria:** DTOs decode actual Trefle API responses without errors

---

### 4.5 Build Trefle Mapper
- [ ] Create `Data/Mappers/TrefleMapper.swift`
- [ ] Implement mapping functions:
  ```swift
  struct TrefleMapper {
      static func mapToPlantCareSchedule(
          from species: TrefleSpeciesDTO,
          plantID: UUID
      ) -> PlantCareSchedule

      static func mapToLightRequirement(
          from light: Int?
      ) -> LightRequirement

      static func mapToWateringSchedule(
          from growth: TrefleGrowthDTO?
      ) -> WateringSchedule

      static func mapToTemperatureRange(
          from growth: TrefleGrowthDTO?
      ) -> TemperatureRange

      static func mapToFertilizerSchedule(
          from growth: TrefleGrowthDTO?
      ) -> FertilizerSchedule?

      static func generateCareTasks(
          from schedule: PlantCareSchedule,
          startDate: Date
      ) -> [CareTask]
  }
  ```
- [ ] Map Trefle light scale (0-10) to `LightRequirement`:
  ```swift
  enum LightRequirement: String, Codable, Sendable {
      case fullShade      // 0-2
      case partialShade   // 3-4
      case partialSun     // 5-6
      case fullSun        // 7-10

      var description: String { ... }
      var hoursOfLight: ClosedRange<Int> { ... }
  }
  ```
- [ ] Map humidity/precipitation to `WateringSchedule`:
  ```swift
  struct WateringSchedule: Codable, Sendable {
      let frequency: WateringFrequency
      let amount: WateringAmount
      let seasonalAdjustments: [Season: WateringFrequency]?

      enum WateringFrequency: String, Codable, Sendable {
          case daily, everyOtherDay, twiceWeekly, weekly, biweekly, monthly

          var intervalDays: Int { ... }
      }

      enum WateringAmount: String, Codable, Sendable {
          case light, moderate, thorough, soak
      }
  }
  ```
- [ ] Map temperature data to `TemperatureRange`:
  ```swift
  struct TemperatureRange: Codable, Sendable {
      let minimum: Measurement<UnitTemperature>
      let maximum: Measurement<UnitTemperature>
      let optimal: Measurement<UnitTemperature>?
      let frostTolerant: Bool
  }
  ```
- [ ] Map soil nutrients to `FertilizerSchedule`:
  ```swift
  struct FertilizerSchedule: Codable, Sendable {
      let frequency: FertilizerFrequency
      let type: FertilizerType
      let seasonalApplication: Bool
      let activeMonths: [Int]?  // 1-12

      enum FertilizerFrequency: String, Codable, Sendable {
          case weekly, biweekly, monthly, quarterly, biannually
      }

      enum FertilizerType: String, Codable, Sendable {
          case balanced, highNitrogen, highPhosphorus, highPotassium, organic
      }
  }
  ```
- [ ] Handle missing data with sensible defaults
- [ ] Unit test all mapping functions

**Acceptance Criteria:** Mapper produces valid care schedules from all Trefle response variations

---

### 4.6 Implement Fetch Plant Care Use Case
- [ ] Create `Domain/UseCases/PlantCare/FetchPlantCareUseCase.swift`
- [ ] Define protocol:
  ```swift
  protocol FetchPlantCareUseCaseProtocol: Sendable {
      func execute(scientificName: String) async throws -> PlantCareInfo
      func execute(trefleId: Int) async throws -> PlantCareInfo
  }
  ```
- [ ] Define `PlantCareInfo` domain entity:
  ```swift
  struct PlantCareInfo: Identifiable, Sendable {
      let id: UUID
      let scientificName: String
      let commonName: String?
      let lightRequirement: LightRequirement
      let wateringSchedule: WateringSchedule
      let temperatureRange: TemperatureRange
      let fertilizerSchedule: FertilizerSchedule?
      let soilType: SoilType?
      let humidity: HumidityLevel?
      let growthRate: GrowthRate?
      let bloomingSeason: [Season]?
      let additionalNotes: String?
      let sourceURL: URL?
  }
  ```
- [ ] Implement use case:
  - Search Trefle by scientific name
  - Fetch detailed species data
  - Map to domain entity
  - Cache results for offline access
- [ ] Handle species not found in Trefle
- [ ] Add fallback to generic care data for unknown species
- [ ] Register in DIContainer

**Acceptance Criteria:** Use case retrieves care data, handles missing species gracefully

---

### 4.7 Create Care Schedule Use Case
- [ ] Create `Domain/UseCases/PlantCare/CreateCareScheduleUseCase.swift`
- [ ] Define protocol:
  ```swift
  protocol CreateCareScheduleUseCaseProtocol: Sendable {
      func execute(
          for plant: Plant,
          careInfo: PlantCareInfo,
          userPreferences: CarePreferences?
      ) async throws -> PlantCareSchedule
  }
  ```
- [ ] Define `CarePreferences`:
  ```swift
  struct CarePreferences: Codable, Sendable {
      let preferredWateringTime: DateComponents  // e.g., 8:00 AM
      let reminderDaysBefore: Int  // remind N days before task
      let groupWateringDays: Bool  // water all plants same day
      let adjustForSeason: Bool
      let location: PlantLocation?

      enum PlantLocation: String, Codable, Sendable {
          case indoor, outdoor, greenhouse, balcony
      }
  }
  ```
- [ ] Implement schedule generation:
  - Calculate next N watering dates (30 days ahead)
  - Calculate fertilizer dates based on schedule
  - Adjust for seasons if enabled
  - Create `CareTask` entities for each scheduled item
- [ ] Define `CareTask` entity:
  ```swift
  struct CareTask: Identifiable, Codable, Sendable {
      let id: UUID
      let plantID: UUID
      let type: CareTaskType
      let scheduledDate: Date
      let isCompleted: Bool
      let completedDate: Date?
      let notes: String?

      enum CareTaskType: String, Codable, Sendable {
          case watering, fertilizing, pruning, repotting, pestControl, rotation

          var icon: String { ... }
          var defaultReminderOffset: TimeInterval { ... }
      }
  }
  ```
- [ ] Persist schedule to Core Data
- [ ] Register in DIContainer

**Acceptance Criteria:** Use case creates complete care schedule with future tasks

---

### 4.8 Build Plant Detail View
- [ ] Create `Presentation/Scenes/PlantDetail/PlantDetailView.swift`
- [ ] Create `PlantDetailViewModel`:
  ```swift
  @Observable
  final class PlantDetailViewModel {
      private(set) var plant: Plant
      private(set) var careInfo: PlantCareInfo?
      private(set) var careSchedule: PlantCareSchedule?
      private(set) var isLoading: Bool = false
      private(set) var error: Error?

      func loadCareInfo() async
      func createSchedule(preferences: CarePreferences?) async
      func markTaskComplete(_ task: CareTask) async
  }
  ```
- [ ] Implement view sections:
  ```swift
  struct PlantDetailView: View {
      @State private var viewModel: PlantDetailViewModel

      var body: some View {
          ScrollView {
              PlantHeaderSection(plant: viewModel.plant)
              IdentificationSection(plant: viewModel.plant)
              CareInformationSection(careInfo: viewModel.careInfo)
              UpcomingTasksSection(tasks: viewModel.upcomingTasks)
              CareScheduleSection(schedule: viewModel.careSchedule)
          }
      }
  }
  ```
- [ ] Create `CareInformationSection` component:
  ```swift
  struct CareInformationSection: View {
      let careInfo: PlantCareInfo?

      var body: some View {
          Section("Care Requirements") {
              LightRequirementRow(requirement: careInfo?.lightRequirement)
              WateringRow(schedule: careInfo?.wateringSchedule)
              TemperatureRow(range: careInfo?.temperatureRange)
              FertilizerRow(schedule: careInfo?.fertilizerSchedule)
              HumidityRow(level: careInfo?.humidity)
          }
      }
  }
  ```
- [ ] Create care info row components:
  - `LightRequirementRow` - sun icon, description, hours
  - `WateringRow` - drop icon, frequency, amount
  - `TemperatureRow` - thermometer, min/max/optimal
  - `FertilizerRow` - leaf icon, frequency, type
  - `HumidityRow` - humidity icon, level indicator
- [ ] Add loading skeleton for care info
- [ ] Handle "care data unavailable" state
- [ ] Implement pull-to-refresh

**Acceptance Criteria:** Detail view displays all plant info with care requirements

---

### 4.9 Implement Care Schedule View
- [ ] Create `Presentation/Scenes/CareSchedule/CareScheduleView.swift`
- [ ] Create `CareScheduleViewModel`:
  ```swift
  @Observable
  final class CareScheduleViewModel {
      private(set) var upcomingTasks: [CareTask] = []
      private(set) var tasksByDate: [Date: [CareTask]] = [:]
      private(set) var plants: [Plant] = []
      var selectedFilter: TaskFilter = .all

      enum TaskFilter: CaseIterable {
          case all, watering, fertilizing, overdue, today
      }

      func loadTasks() async
      func markComplete(_ task: CareTask) async
      func snoozeTask(_ task: CareTask, until: Date) async
      func skipTask(_ task: CareTask) async
  }
  ```
- [ ] Implement main schedule view:
  ```swift
  struct CareScheduleView: View {
      @State private var viewModel: CareScheduleViewModel

      var body: some View {
          NavigationStack {
              List {
                  OverdueTasksSection(tasks: viewModel.overdueTasks)
                  TodayTasksSection(tasks: viewModel.todayTasks)
                  UpcomingTasksSection(tasksByDate: viewModel.upcomingByDate)
              }
              .navigationTitle("Care Schedule")
              .toolbar {
                  FilterMenu(selection: $viewModel.selectedFilter)
              }
          }
      }
  }
  ```
- [ ] Create `CareTaskRow` component:
  ```swift
  struct CareTaskRow: View {
      let task: CareTask
      let plant: Plant
      let onComplete: () -> Void
      let onSnooze: (Date) -> Void

      var body: some View {
          HStack {
              PlantThumbnail(plant: plant)
              VStack(alignment: .leading) {
                  Text(plant.commonNames.first ?? plant.scientificName)
                  Text(task.type.rawValue.capitalized)
                      .font(.caption)
                      .foregroundStyle(.secondary)
              }
              Spacer()
              TaskActionButtons(...)
          }
          .swipeActions { ... }
      }
  }
  ```
- [ ] Implement calendar view option:
  ```swift
  struct CareCalendarView: View {
      let tasksByDate: [Date: [CareTask]]
      @Binding var selectedDate: Date

      var body: some View {
          VStack {
              CalendarGrid(tasksByDate: tasksByDate, selection: $selectedDate)
              TaskListForDate(tasks: tasksByDate[selectedDate] ?? [])
          }
      }
  }
  ```
- [ ] Add empty state for "no tasks scheduled"
- [ ] Implement batch actions (complete all today's watering)
- [ ] Add quick-add task functionality

**Acceptance Criteria:** Schedule view shows all upcoming tasks, supports filtering and completion

---

### 4.10 Add Local Notifications for Care Reminders
- [ ] Create `Core/Services/NotificationService.swift`
- [ ] Define protocol:
  ```swift
  protocol NotificationServiceProtocol: Sendable {
      func requestAuthorization() async throws -> Bool
      func scheduleReminder(for task: CareTask, plant: Plant) async throws
      func cancelReminder(for task: CareTask) async
      func cancelAllReminders(for plantID: UUID) async
      func updateBadgeCount() async
      func getPendingNotifications() async -> [UNNotificationRequest]
  }
  ```
- [ ] Implement notification service:
  ```swift
  final class NotificationService: NotificationServiceProtocol {
      private let center = UNUserNotificationCenter.current()

      func scheduleReminder(for task: CareTask, plant: Plant) async throws {
          let content = UNMutableNotificationContent()
          content.title = "Plant Care Reminder"
          content.body = "\(plant.commonNames.first ?? plant.scientificName) needs \(task.type.rawValue)"
          content.sound = .default
          content.badge = await calculateBadgeCount() as NSNumber
          content.userInfo = [
              "taskID": task.id.uuidString,
              "plantID": plant.id.uuidString,
              "taskType": task.type.rawValue
          ]
          content.categoryIdentifier = "CARE_REMINDER"

          let trigger = UNCalendarNotificationTrigger(
              dateMatching: Calendar.current.dateComponents(
                  [.year, .month, .day, .hour, .minute],
                  from: task.scheduledDate
              ),
              repeats: false
          )

          let request = UNNotificationRequest(
              identifier: "care-\(task.id.uuidString)",
              content: content,
              trigger: trigger
          )

          try await center.add(request)
      }
  }
  ```
- [ ] Set up notification categories and actions:
  ```swift
  func setupNotificationCategories() {
      let completeAction = UNNotificationAction(
          identifier: "COMPLETE",
          title: "Mark Complete",
          options: .foreground
      )

      let snoozeAction = UNNotificationAction(
          identifier: "SNOOZE",
          title: "Snooze 1 Hour",
          options: []
      )

      let category = UNNotificationCategory(
          identifier: "CARE_REMINDER",
          actions: [completeAction, snoozeAction],
          intentIdentifiers: [],
          options: .customDismissAction
      )

      UNUserNotificationCenter.current().setNotificationCategories([category])
  }
  ```
- [ ] Handle notification responses in app delegate/scene delegate
- [ ] Create `ScheduleNotificationsUseCase`:
  ```swift
  protocol ScheduleNotificationsUseCaseProtocol: Sendable {
      func scheduleAll(for schedule: PlantCareSchedule, plant: Plant) async throws
      func rescheduleAll() async throws  // Call after task completion
      func syncWithSystem() async  // Verify scheduled vs expected
  }
  ```
- [ ] Add notification settings UI:
  - Enable/disable reminders
  - Set default reminder time
  - Set advance notice period
  - Sound selection
- [ ] Handle notification permission denied gracefully
- [ ] Register in DIContainer

**Acceptance Criteria:** Notifications fire at scheduled times with actionable buttons

---

## End-of-Phase Validation

### Functional Verification

| Test | Steps | Expected Result | Status |
|------|-------|-----------------|--------|
| API Token Configured | Build app | No crash on Trefle token access | [ ] |
| Plant Search | Search "Monstera" | Returns matching species | [ ] |
| Species Detail | Fetch species by slug | Returns complete growth data | [ ] |
| Care Info Display | View identified plant | Care requirements shown | [ ] |
| Schedule Creation | Add plant to collection | Care schedule generated | [ ] |
| Task List | Open care schedule tab | Upcoming tasks displayed | [ ] |
| Task Completion | Tap complete on task | Task marked done, removed from list | [ ] |
| Task Snooze | Snooze task 1 hour | Task rescheduled, notification updated | [ ] |
| Notification Permission | First launch | Permission dialog shown | [ ] |
| Notification Delivery | Wait for scheduled time | Notification appears | [ ] |
| Notification Action | Tap "Mark Complete" | App opens, task completed | [ ] |
| Offline Care Data | Disable network | Cached care info displayed | [ ] |
| Unknown Species | Search non-existent plant | Graceful "not found" message | [ ] |
| Calendar View | Switch to calendar | Tasks shown on correct dates | [ ] |
| Filter Tasks | Filter by "watering" | Only watering tasks shown | [ ] |

### Code Quality Verification

| Check | Criteria | Status |
|-------|----------|--------|
| Build | Project builds with zero warnings | [ ] |
| Architecture | Trefle code isolated in Data/DataSources/Remote/TrefleAPI/ | [ ] |
| Protocols | All services use protocols for testability | [ ] |
| Sendable | All new types conform to Sendable | [ ] |
| DTOs | DTOs decode sample Trefle responses correctly | [ ] |
| Mapper | Mapper handles all optional fields with defaults | [ ] |
| Use Cases | Business logic in use cases, not ViewModels | [ ] |
| DI Container | New services registered in container | [ ] |
| Error Types | Trefle-specific errors defined | [ ] |
| Unit Tests | DTOs, mappers, and use cases have tests | [ ] |
| Secrets | API token not in source control | [ ] |
| Notifications | Permission handling follows Apple guidelines | [ ] |

### Performance Verification

| Metric | Target | Actual | Status |
|--------|--------|--------|--------|
| Trefle Search Response | < 2 seconds | | [ ] |
| Species Detail Fetch | < 3 seconds | | [ ] |
| Care Schedule Generation | < 100ms | | [ ] |
| Plant Detail View Load | < 500ms | | [ ] |
| Care Schedule View Load | < 300ms | | [ ] |
| Notification Scheduling (batch) | < 1 second for 10 tasks | | [ ] |
| Care Info Cache Lookup | < 50ms | | [ ] |
| Calendar View Render | < 200ms | | [ ] |

### API Integration Verification

| Test | Steps | Expected Result | Status |
|------|-------|-----------------|--------|
| Valid Species | Search "Quercus robur" | Returns oak species data | [ ] |
| Growth Data Present | Fetch species with growth | Light, water, temp data present | [ ] |
| Growth Data Missing | Fetch species without growth | Defaults used, no crash | [ ] |
| Pagination | Search common term | Multiple pages available | [ ] |
| Rate Limiting | Make rapid requests | 429 handled gracefully | [ ] |
| Invalid Token | Use wrong token | Unauthorized error shown | [ ] |
| Species Not Found | Search gibberish | Empty results, no error | [ ] |
| Image URLs | Fetch species | Valid image URLs returned | [ ] |

### Care Schedule Verification

| Scenario | Input | Expected Output | Status |
|----------|-------|-----------------|--------|
| Daily Watering | High humidity plant | Tasks every day | [ ] |
| Weekly Watering | Low humidity plant | Tasks every 7 days | [ ] |
| Monthly Fertilizer | High nutrient need | Tasks every 30 days | [ ] |
| No Fertilizer | Low nutrient need | No fertilizer tasks | [ ] |
| Seasonal Adjustment | Outdoor plant in winter | Reduced watering frequency | [ ] |
| User Preferred Time | Set 9:00 AM | All tasks at 9:00 AM | [ ] |
| 30-Day Lookahead | Create schedule | Tasks for next 30 days | [ ] |
| Task Completion | Complete watering | Next occurrence scheduled | [ ] |
| Plant Deletion | Delete plant | All tasks removed | [ ] |

### Notification Verification

| Test | Steps | Expected Result | Status |
|------|-------|-----------------|--------|
| Permission Granted | Accept notification prompt | Reminders scheduled | [ ] |
| Permission Denied | Deny notification prompt | Graceful fallback, in-app alerts | [ ] |
| Notification Content | Receive notification | Correct plant name and task type | [ ] |
| Complete Action | Tap "Mark Complete" | Task completed in app | [ ] |
| Snooze Action | Tap "Snooze" | Notification rescheduled | [ ] |
| Badge Count | Have 3 overdue tasks | Badge shows 3 | [ ] |
| Badge Clear | Complete all tasks | Badge cleared | [ ] |
| Background Delivery | App closed | Notification still fires | [ ] |
| Notification Tap | Tap notification | Opens plant detail | [ ] |
| Bulk Reschedule | Complete task | Future notifications updated | [ ] |

---

## Phase 4 Completion Checklist

- [ ] All 10 tasks completed (core implementation)
- [ ] All functional tests pass
- [ ] All code quality checks pass
- [ ] All performance targets met
- [ ] Trefle API integration verified
- [ ] Care schedule generation working
- [ ] Task management (complete/snooze/skip) working
- [ ] Notifications scheduling and firing correctly
- [ ] Notification actions handled properly
- [ ] Offline mode works (cached care data)
- [ ] API token secured (not in git)
- [ ] Unit tests for DTOs, mappers, and use cases
- [ ] UI tests for critical flows (view plant, complete task)
- [ ] Code committed with descriptive message
- [ ] Ready for Phase 5 (Plant Collection & Persistence)

---

## Error Handling

### Trefle API Errors
```swift
enum TrefleAPIError: Error, LocalizedError {
    case invalidToken
    case rateLimitExceeded
    case speciesNotFound(query: String)
    case serverError(statusCode: Int)
    case networkUnavailable
    case timeout
    case invalidResponse
    case paginationExhausted

    var errorDescription: String? {
        switch self {
        case .invalidToken:
            return "Invalid API token. Please check configuration."
        case .rateLimitExceeded:
            return "Too many requests. Please wait a moment."
        case .speciesNotFound(let query):
            return "No species found matching '\(query)'."
        case .serverError(let code):
            return "Server error (\(code)). Please try again later."
        case .networkUnavailable:
            return "No network connection."
        case .timeout:
            return "Request timed out. Please try again."
        case .invalidResponse:
            return "Invalid response from server."
        case .paginationExhausted:
            return "No more results available."
        }
    }
}
```

### Care Schedule Errors
```swift
enum CareScheduleError: Error, LocalizedError {
    case noCareDataAvailable
    case schedulePersistenceFailed
    case invalidDateRange
    case plantNotFound

    var errorDescription: String? {
        switch self {
        case .noCareDataAvailable:
            return "Care information not available for this plant."
        case .schedulePersistenceFailed:
            return "Failed to save care schedule."
        case .invalidDateRange:
            return "Invalid date range for schedule."
        case .plantNotFound:
            return "Plant not found in collection."
        }
    }
}
```

### Notification Errors
```swift
enum NotificationError: Error, LocalizedError {
    case permissionDenied
    case schedulingFailed
    case invalidTriggerDate
    case categoryNotRegistered

    var errorDescription: String? {
        switch self {
        case .permissionDenied:
            return "Notification permission denied. Enable in Settings."
        case .schedulingFailed:
            return "Failed to schedule reminder."
        case .invalidTriggerDate:
            return "Cannot schedule reminder for past date."
        case .categoryNotRegistered:
            return "Notification category not configured."
        }
    }
}
```

---

## Notes

- Trefle API has growth data for ~10% of species; implement graceful fallbacks
- Cache Trefle responses aggressively (data rarely changes)
- Notification limit: iOS allows ~64 pending local notifications
- Schedule notifications in batches to stay under limit
- Use background app refresh to reschedule notifications periodically
- Consider user's timezone for notification scheduling
- Trefle measurement units vary; normalize to metric internally, display in user's preference
- Some plants need seasonal care adjustments (reduce watering in winter)
- Badge count should only reflect overdue tasks, not all pending
- Test notification actions with app in foreground, background, and terminated states

---

## Dependencies

| Dependency | Type | Notes |
|------------|------|-------|
| Trefle API | External API | 120 req/min rate limit |
| UserNotifications | System | Local notifications |
| URLSession | System | API requests |
| Core Data | System | Schedule persistence |

---

## Risk Mitigation

| Risk | Mitigation |
|------|------------|
| Trefle API token exposed | Use xcconfig, add to .gitignore |
| Species not in Trefle | Provide generic care defaults |
| Missing growth data | Use conservative defaults for watering/light |
| Notification permission denied | In-app task list always available |
| Too many notifications | Limit to 64, prioritize soonest tasks |
| User ignores reminders | Badge count, overdue section in UI |
| Trefle API downtime | Cache responses, retry with backoff |
| Incorrect care recommendations | Add disclaimer, allow user overrides |
| Timezone issues | Store all dates in UTC, convert for display |
| App deleted with pending notifications | Notifications orphaned (OS handles cleanup) |

---

## Sample Trefle API Response

### Search Response
```json
{
  "data": [
    {
      "id": 834,
      "common_name": "Swiss cheese plant",
      "slug": "monstera-deliciosa",
      "scientific_name": "Monstera deliciosa",
      "year": 1849,
      "bibliography": "Vidensk. Meddel. Naturhist. Foren. Kjøbenhavn 1849: 19 (1849)",
      "author": "Liebm.",
      "family_common_name": "Arum family",
      "genus_id": 1254,
      "image_url": "https://bs.plantnet.org/image/o/abc123",
      "genus": "Monstera",
      "family": "Araceae"
    }
  ],
  "links": {
    "self": "/api/v1/plants/search?q=monstera",
    "first": "/api/v1/plants/search?page=1&q=monstera",
    "last": "/api/v1/plants/search?page=1&q=monstera"
  },
  "meta": {
    "total": 12
  }
}
```

### Species Detail Response
```json
{
  "data": {
    "id": 834,
    "common_name": "Swiss cheese plant",
    "slug": "monstera-deliciosa",
    "scientific_name": "Monstera deliciosa",
    "growth": {
      "light": 6,
      "atmospheric_humidity": 8,
      "minimum_temperature": {
        "deg_c": 15
      },
      "maximum_temperature": {
        "deg_c": 30
      },
      "soil_humidity": 7,
      "soil_nutriments": 5
    },
    "specifications": {
      "growth_rate": "moderate",
      "toxicity": "mild"
    }
  },
  "meta": {
    "last_modified": "2023-01-15T12:00:00Z"
  }
}
```

---

## UI Mockups (Conceptual)

### Plant Detail - Care Section
```
┌─────────────────────────────────────┐
│  ☀️ Light: Partial Sun (5-6 hrs)    │
│  💧 Water: Twice Weekly (Moderate)  │
│  🌡️ Temp: 15-30°C (Optimal: 22°C)  │
│  🌱 Fertilizer: Monthly (Balanced)  │
│  💨 Humidity: High                  │
└─────────────────────────────────────┘
```

### Care Schedule - Task List
```
┌─────────────────────────────────────┐
│ OVERDUE (2)                         │
│ ┌─────────────────────────────────┐ │
│ │ 🪴 Monstera    💧 Water   [✓]  │ │
│ │ 🪴 Pothos      💧 Water   [✓]  │ │
│ └─────────────────────────────────┘ │
│                                     │
│ TODAY                               │
│ ┌─────────────────────────────────┐ │
│ │ 🪴 Ficus       🌱 Fertilize [✓]│ │
│ └─────────────────────────────────┘ │
│                                     │
│ TOMORROW                            │
│ ┌─────────────────────────────────┐ │
│ │ 🪴 Snake Plant 💧 Water   [○]  │ │
│ └─────────────────────────────────┘ │
└─────────────────────────────────────┘
```