# CLAUDE.md — JQC iOS App Developer Reference

> **Audience:** AI assistants and developers working on the JanitorialQC iPad app.
> **Purpose:** Authoritative reference for architecture, conventions, constraints, and decisions.
> **Last reviewed:** May 2026 (Phase 18 complete — static DateFormatter, uploadPhoto retry guard, explicit LocalIssue relationship inverse, APIUser.fullName/displayName, build fixes: SyncManager.shared restored, _RefreshEnvelope nonisolated init)
> **Companion:** See the web backend's `CLAUDE.md` for API contract, server-side rules, and migration chain.

---

## Table of Contents

1. [Project Overview](#1-project-overview)
2. [Tech Stack](#2-tech-stack)
3. [Repository Layout](#3-repository-layout)
4. [App Entry Point & Lifecycle](#4-app-entry-point--lifecycle)
5. [Authentication](#5-authentication)
6. [SwiftData Models](#6-swiftdata-models)
7. [Offline-First Architecture](#7-offline-first-architecture)
8. [Sync Engine (SyncManager)](#8-sync-engine-syncmanager)
9. [API Client (APIClient)](#9-api-client-apiclient)
10. [Navigation & View Hierarchy](#10-navigation--view-hierarchy)
11. [Inspection Workflow](#11-inspection-workflow)
12. [Form Field Rendering](#12-form-field-rendering)
13. [Issue Flagging Workflow](#13-issue-flagging-workflow)
14. [Re-inspection Workflow](#14-re-inspection-workflow)
15. [Inspection History](#15-inspection-history)
16. [Photo Handling](#16-photo-handling)
17. [Score Calculation](#17-score-calculation)
18. [Background Sync](#18-background-sync)
19. [Settings & Cache Management](#19-settings--cache-management)
20. [Known Constraints & Hard Rules](#20-known-constraints--hard-rules)
21. [Xcode 26 Specific Issues](#21-xcode-26-specific-issues)
22. [Change Philosophy](#22-change-philosophy)

---

## 1. Project Overview

**JanitorialQC Inspector** is a native iPadOS app used by inspectors to conduct facility quality-control inspections. Its defining characteristic is **offline-first operation**: every action writes to local SwiftData storage first; the server is a secondary destination reached asynchronously when connectivity allows.

Core capabilities:
- **Login/logout** via JWT against the JQC web backend API
- **Reference data sync** — facilities, areas, and inspection templates pulled from server
- **Inspection execution** — dynamic form rendering driven by server-side template schemas
- **Issue flagging** — severity-tagged issues with optional photos, attached to inspections; confirmation banner shown on submit
- **Re-inspection** — linked follow-up inspections with parent-form pre-fill (template, contract, facility all pre-filled)
- **Outbox queue** — completed inspections and issues submitted to server automatically when online
- **Inspection history** — server-side read-only history for completed inspections
- **Issues list** — assigned issues pulled from server + device-created issues; stale unassigned records removed on sync
- **Issue detail** — shows local photos and server-hosted photos via `AsyncImage`
- **Facilities browser** — read-only view of synced facilities and their areas
- **Push notifications** — local notifications for issue assignments and follow-up requests via 60-second polling

---

## 2. Tech Stack

| Layer | Technology |
|---|---|
| Language | Swift 5.10+ |
| UI | SwiftUI (iPad-only, all four orientations) |
| Local storage | SwiftData (iOS 17+ required) |
| Networking | URLSession async/await |
| Connectivity detection | NWPathMonitor (Network.framework) |
| Token storage | iOS Keychain (Security.framework) |
| Photo capture | UIImagePickerController (camera), PHPickerViewController (library) |
| Signature capture | PencilKit (PKCanvasView) |
| Background tasks | BGTaskScheduler / BGProcessingTask |
| Min deployment | iOS 17.0 |
| Xcode | **26.4.1** (Xcode 26 beta — see §21 for critical constraints) |

---

## 3. Repository Layout

```
JanitorialQC/
├── JanitorialQCApp.swift        # @main — SwiftData container, BGTask registration
├── ContentView.swift            # Auth gate + startup lifecycle (.task{})
│
├── Auth/
│   ├── AuthManager.swift        # @MainActor ObservableObject — login/logout/restore
│   └── KeychainHelper.swift     # Security.framework wrapper (nonisolated)
│
├── API/
│   ├── APIClient.swift          # actor — URLSession, JWT inject, 401-retry, photo upload
│   └── APIModels.swift          # All Codable/Sendable response DTOs
│
├── Sync/
│   └── SyncManager.swift        # @MainActor ObservableObject — NWPathMonitor, outbox queue
│
├── Models/                      # SwiftData @Model classes — NO other .swift files here
│   ├── LocalFacility.swift
│   ├── LocalArea.swift
│   ├── LocalTemplate.swift
│   ├── LocalInspection.swift    # ← ONLY definition of LocalInspection — never duplicate
│   ├── LocalIssue.swift
│   ├── PendingPhoto.swift
│   └── SyncQueueEntry.swift
│
├── Views/
│   ├── Auth/
│   │   └── LoginView.swift      # ← Auth/ folder must contain ONLY auth files — no models
│   ├── Dashboard/
│   │   ├── DashboardView.swift
│   │   ├── StartInspectionView.swift
│   │   ├── ExecuteInspectionView.swift
│   │   ├── FlagIssueView.swift
│   │   └── FormFieldView.swift
│   └── Inspection/
│       └── InspectionHistoryView.swift
│
└── Utils/
    └── Constants.swift
```

**Critical:** This project uses `PBXFileSystemSynchronizedRootGroup` (Xcode 16+ folder sync). Xcode **automatically compiles every `.swift` file in the folder tree**. There is no explicit file list. A stray duplicate (e.g. a model file accidentally placed in the wrong folder) will cause "Multiple commands produce" build errors. Always verify file locations after any copy/paste operation.

---

## 4. App Entry Point & Lifecycle

### JanitorialQCApp.swift

`@main` struct. Responsibilities:
1. Creates the SwiftData `ModelContainer` for all seven model types.
2. In the container success callback: sets **only** `SyncManager.shared.modelContext`. Nothing else — no async calls, no session restore.
3. Registers the `com.jqc.sync` `BGProcessingTask` identifier.

**Critical:** The `modelContainer` callback runs on a background thread. Do NOT call `restoreSession()` or `startMonitoring()` from inside this callback. Doing so causes a race condition where `NWPathMonitor` fires `triggerSync()` before auth tokens are loaded, producing a 401 loop that leaves `isLoading` stuck at `true` and the app frozen on the splash screen.

### ContentView.swift

Auth gate and **startup lifecycle owner**. The `.task {}` modifier owns the startup sequence:

```swift
.task {
    await AuthManager.shared.restoreSession()   // 1. auth first
    SyncManager.shared.startMonitoring()        // 2. monitor after auth resolves
    if SyncManager.shared.isOnline && AuthManager.shared.isAuthenticated {
        await SyncManager.shared.triggerSync()  // 3. sync only if authenticated
    }
}
```

**The order is mandatory.** `startMonitoring()` must not be called before `restoreSession()` completes because NWPathMonitor fires immediately on network availability, triggering `triggerSync()` before tokens are in Keychain.

### Background transitions

`DashboardView` observes `.scenePhase` and calls `scheduleBackgroundSync()` every time the app moves to `.background`.

---

## 5. Authentication

### AuthManager

`@MainActor class AuthManager: ObservableObject` — singleton via `AuthManager.shared`.

| Property | Purpose |
|---|---|
| `isAuthenticated` | Master gate — drives ContentView routing |
| `isLoading` | Shows spinner during network calls |
| `errorMessage` | Shown inline on LoginView |
| `currentUserId/Username/Role/DisplayName` | User identity persisted to Keychain |

**Session restore flow (`restoreSession`):**
1. If no access token in Keychain → `isAuthenticated = false` immediately (no network call).
2. Calls `GET /api/v1/auth/me` to validate the stored token.
3. On `notAuthenticated` error → clears Keychain, sets unauthenticated.
4. On any other error (network timeout, server 500) → restores user identity from Keychain and sets authenticated. This allows offline launch.

**Logout flow:** Calls `POST /api/v1/auth/logout` with the refresh token (best-effort), then clears all Keychain keys and sets `isAuthenticated = false`.

### KeychainHelper

`nonisolated` static methods wrapping `Security.framework`. All keys use `kSecAttrAccessibleAfterFirstUnlock` so tokens are readable for background sync after device reboot.

Stored keys (all prefixed `com.jqc.`):

| Key constant | Value stored |
|---|---|
| `accessToken` | JWT Bearer token |
| `refreshToken` | Opaque 64-char hex refresh token |
| `userId` | User ID as string |
| `userRole` | Role string (e.g. `inspector`) |
| `username` | Login username |
| `displayName` | Display name |

---

## 6. SwiftData Models

### Model Container Registration

All models are registered in `JanitorialQCApp` in this order:

```swift
LocalFacility.self, LocalArea.self, LocalTemplate.self,
LocalInspection.self, LocalIssue.self, PendingPhoto.self, SyncQueueEntry.self
```

**SwiftData lightweight migration:** Adding a new `Bool` property to any model **requires a default value** (e.g. `var followUpRequired: Bool = false`) — without a default the app crashes on launch after the model change.

### Model Reference

| Model | Role | Key fields |
|---|---|---|
| `LocalFacility` | Read-only cached facility reference | `serverId`, `name`, `address`, `projectName`, `areas` (cascade) |
| `LocalArea` | Read-only cached area reference | `serverId`, `facilityServerId`, `name`, `areaType` |
| `LocalTemplate` | Cached template + raw JSON schema | `serverId`, `formSchemaJSON`, `formSchema` (computed) |
| `LocalInspection` | Inspector-authored inspection record | `localId` (UUID, unique), `serverId`, `status`, `syncStatus`, `formDataJSON`, `followUpRequired`, `parentLocalId`, `parentServerId` |
| `LocalIssue` | Issue flagged during inspection | `localId` (UUID, unique), `serverId`, `inspectionLocalId`, `facilityServerId`, `severity`, `syncStatus` |
| `PendingPhoto` | Photo awaiting upload | `localId`, `localFilePath`, `serverPath`, `uploadStatus`, `entityType`, `fieldId` |
| `SyncQueueEntry` | Outbox entry (currently informational) | `entityType`, `localId`, `syncStatus`, `payloadJSON` |

### LocalInspection Status Flow

```
"draft" → "completed" → "synced"
                      → "failed"  (after 5 retries)
```

`status` = inspector workflow state. `syncStatus` = server submission state (`"pending"` | `"synced"` | `"failed"`). They are separate fields.

### formData Storage

`LocalInspection.formData` is a computed property that JSON-serialises to/from `formDataJSON: String`. Keys are always **strings** (field IDs stringified). Values are `Any` (String, Int, Bool, Array, Dict). Do not store `UIImage` or any non-JSON-serialisable type in `formData`.

---

## 7. Offline-First Architecture

The app follows the **outbox pattern**:

```
Inspector action → SwiftData write (always succeeds immediately)
                       ↓
               syncStatus = "pending"
                       ↓
         NWPathMonitor detects connectivity
                       ↓
         SyncManager.triggerSync()
         1. Upload pending photos (processPhotoQueue)
         2. Submit completed inspections (processInspectionQueue)
         3. Submit pending issues (processIssueQueue)
         4. Pull fresh reference data (pullReferenceData)
         5. Pull + reconcile assigned issues (pullAssignedIssues)
         6. Poll server notifications (pollNotifications)
```

The UI never blocks on network. Every screen is driven by local SwiftData queries.

---

## 8. Sync Engine (SyncManager)

`@MainActor class SyncManager: ObservableObject` — singleton via `SyncManager.shared`.

### Published state

| Property | Purpose |
|---|---|
| `isOnline` | True when `NWPathMonitor` reports `.satisfied` |
| `isSyncing` | True during active sync cycle |
| `lastSyncAt` | Date of last completed sync |
| `syncError` | Last error string (shown in Settings and Pending Sync views) |
| `pendingCount` | Count of unsynced inspections + issues (shown as badge) |

### triggerSync() guard

`triggerSync()` guards on **three conditions** before doing any work:

```swift
guard isOnline, let context = modelContext, AuthManager.shared.isAuthenticated else { return }
```

The `isAuthenticated` guard is critical. `NWPathMonitor` fires immediately on connectivity, including during app startup before `restoreSession()` completes. Without this guard, `triggerSync()` runs with no valid token, hits a 401, attempts token refresh, fails with `notAuthenticated`, and the error propagates up through the `.task{}` startup chain — leaving `isLoading` stuck at `true`.

### triggerSync() — processing order

1. `processPhotoQueue` — upload all `PendingPhoto` with `uploadStatus == "pending"`. On success, propagates `serverPath` to the parent `LocalInspection.formData` (image fields) or `LocalIssue.photoServerPath`. Uses fetch-all + filter in Swift — no `#Predicate`.
2. `processInspectionQueue` — submits completed inspections only when all `pendingPhotos` are settled. Clears `followUpRequired` on parent after sync.
3. `processIssueQueue` — guards against submitting when parent inspection `syncStatus == "failed"` (prevents orphaned server records). Uses fetch-all + filter in Swift.
4. `pullReferenceData` — fetches facilities, areas, and templates. Sequential `await` calls — not `async let`.
5. `pullAssignedIssues` — fetches `GET /api/v1/issues` (scoped to current user on server). Upserts into SwiftData keyed by `serverId`. **Deletion pass** removes local records with `syncStatus == "synced"` + `inspectionLocalId == ""` whose `serverId` is absent from the response — handles reassignment away from this inspector. Empty response is not short-circuited so full unassignment is handled.
6. `pollNotifications` — fetches `GET /api/v1/notifications?since=<last_fetch>`. Delivers each item as a local `UNUserNotificationCenter` banner. Updates cursor timestamp. Marks fetched IDs read on server.

### Notification polling

- `startPollTask()` creates a `Task` with a `Task.sleep(nanoseconds: 60_000_000_000)` loop. Called from `startMonitoring()` whenever connectivity is `.satisfied`.
- `stopPollTask()` cancels the task. Called when connectivity drops.
- `resetNotificationPoller()` cancels task + clears `lastNotificationFetch`. Call on logout.
- **`Timer.scheduledTimer` is banned for periodic work in SyncManager.** Timer requires `RunLoop.main` to be ticking; inside a Swift Concurrency `Task { @MainActor }` block `RunLoop.current` ≠ `RunLoop.main` — the timer fires silently never. Always use `Task.sleep`.
- **`UNUserNotificationCenterDelegate` is required for foreground delivery.** Without it, iOS silently drops local notifications when the app is active. `NotificationDelegate.shared` is set as `UNUserNotificationCenter.current().delegate` in `JanitorialQCApp.init()`. Its `willPresent` returns `[.banner, .sound]`.
- **`Self.isoFormatter` for all date parsing.** `SyncManager.isoFormatter` is a `nonisolated static let DateFormatter` with `locale = Locale(identifier: "en_US_POSIX")` and `dateFormat = "yyyy-MM-dd'T'HH:mm:ss"`. Used by both `pollNotifications()` and `pullAssignedIssues()`. **Never allocate a `DateFormatter` per call or per loop iteration** — it is expensive. The `en_US_POSIX` locale is mandatory for fixed-format parsing; without it, the system locale can reinterpret the format string unpredictably.

### Fetch pattern — CRITICAL for Xcode 26

**Never use `#Predicate` anywhere in `SyncManager`.** Under Xcode 26 with `SWIFT_DEFAULT_ACTOR_ISOLATION = MainActor`, `#Predicate` with a captured `String` variable inside a `@MainActor` async function causes `LocalInspection is ambiguous for type lookup` — a cascade of compiler errors.

**Never use the chained optional pattern:**
```swift
// WRONG — compiler cannot infer T in this chained expression
let x = (try? context.fetch(FetchDescriptor<LocalInspection>()))?.filter { ... } ?? []

// CORRECT — split into two statements
let all = (try? context.fetch(FetchDescriptor<LocalInspection>())) ?? []
let x   = all.filter { ... }
```

**Always parenthesise `try?` before `??`:**
```swift
// WRONG — operator precedence: try? binds looser than ??
// parses as: try? (context.fetch(...) ?? []) — nonsensical, fetch() is not Optional
let all = try? context.fetch(FetchDescriptor<LocalInspection>()) ?? []

// CORRECT
let all = (try? context.fetch(FetchDescriptor<LocalInspection>())) ?? []
```

### Retry / failure

- Each item increments `syncRetryCount` on every failure.
- At 5 retries: `syncStatus = "failed"`. The item stays in SwiftData but is never retried automatically.
- `syncError` is cleared at the start of each `triggerSync()` call.

---

## 9. API Client (APIClient)

`actor APIClient` — singleton via `APIClient.shared`. All methods are `async throws`.

### Generic request pipeline

```swift
request(endpoint, method, body, retrying) async throws -> T
```

1. Builds URL from `Constants.baseURL + endpoint`.
2. Injects Bearer token from Keychain.
3. Performs `URLSession.data(for:)`.
4. On HTTP 401 and `retrying == false`: calls `refreshAccessToken()` once, retries. If refresh fails → `APIError.notAuthenticated`.
5. Decodes via `_Envelope<T>` (wraps `ok: Bool`, `data: T?`, `error: String?`).

### Key methods

| Method | Endpoint | Notes |
|---|---|---|
| `request<T>` | Any | Generic GET/POST; `retrying: Bool` prevents double-refresh loop |
| `post<T>` | Any | POST convenience |
| `uploadPhoto` | `POST /api/v1/photos/upload` | Multipart form-data, manual boundary; `retrying: Bool = false` matches `request()` retry pattern |
| `submitInspection` | `POST /api/v1/inspections` | Sanitises `local://` photo paths before send |
| `submitIssue` | `POST /api/v1/issues` | Sends `inspection_id` only if `inspection.serverId` is non-nil |
| `fetchInspectionHistory` | `GET /api/v1/inspections` | Paginated, returns `InspectionHistoryResponseData` |
| `fetchAssignedIssues` | `GET /api/v1/issues` | Returns issues assigned to OR reported by current user |
| `fetchIssueDetail` | `GET /api/v1/issues/<id>` | Fetches current status for detail view |
| `updateIssueStatus` | `PATCH /api/v1/issues/<id>/status` | Inspector updates status on assigned/reported issues |
| `fetchNotifications` | `GET /api/v1/notifications` | Accepts optional `since: Date`; returns `[APINotification]` |
| `markNotificationsRead` | `PATCH /api/v1/notifications/mark-read` | Marks list of IDs read on server |

### Token refresh

`refreshAccessToken()` uses a **local** `JSONDecoder` (not `self.decoder`) to avoid Swift 6 actor-isolation errors. It stores both new tokens in Keychain before returning.

### JSON decoding

`decoder.keyDecodingStrategy = .convertFromSnakeCase` — all snake_case server fields map to camelCase Swift properties automatically.

### `JSONValue` / `AnyDecodable`

`AnyDecodable` is a `typealias` for `JSONValue`, a typed enum replacing `Any` to achieve full `Sendable` conformance. Use `.anyValue` to bridge to `Any` where legacy code expects it.

---

## 10. Navigation & View Hierarchy

```
JanitorialQCApp
└── ContentView (auth gate + startup lifecycle)
    ├── LoginView                        (unauthenticated)
    └── DashboardView                    (authenticated)
        ├── Sidebar (NavigationSplitView — no selection: binding)
        │   ├── My Inspections  → MyInspectionsView
        │   ├── Issues          → IssuesListView
        │   ├── Facilities      → FacilitiesListView
        │   ├── Pending Sync    → SyncStatusView
        │   ├── History         → InspectionHistoryView
        │   └── Settings        → SettingsView
        └── + button → StartInspectionView (sheet)
                           └── ExecuteInspectionView (navigation push)
                                   └── FlagIssueView (sheet)
```

**`NavigationSplitView` constraint:** `init(selection:content:)` is unavailable on iPadOS 17. Navigation is driven by `@State var selectedTab: SidebarTab` with manual `Button` handlers. **Never add a `selection:` binding.**

---

## 11. Inspection Workflow

### 1. Start (`StartInspectionView`)

- Inspector picks template (required), facility (required), area (optional).
- Tapping Start creates a `LocalInspection` in SwiftData immediately (`status = "draft"`, `syncStatus = "pending"`) and navigates to `ExecuteInspectionView`.
- For re-inspections: template and facility are pre-filled; non-scoring fields from the parent are copied into `formData` (rating, pass_fail, image, signature fields are always blank).

### 2. Execute (`ExecuteInspectionView`)

- Renders the template's `formSchema` as a 12-column CSS-grid-equivalent layout via `GridFormView`.
- Auto-saves every 30 seconds to SwiftData.
- Saves on `onDisappear`.
- "Flag an Issue" button opens `FlagIssueView` as a sheet.
- "Save Draft" force-saves with a brief spinner feedback.
- "Submit Inspection" shows a confirmation alert, then:
  1. Persists final `formData` to SwiftData.
  2. Computes `overallScore` via `computeScore(fromSchema:)`.
  3. Sets `status = "completed"`, `syncStatus = "pending"`, `completedAt = Date()`.
  4. Calls `clearParentFollowUpFlag()` immediately (badge clears on device before sync).
  5. Triggers `SyncManager.triggerSync()` in the background if online.
  6. Shows a success banner for 2.5 seconds then dismisses.

### 3. Draft management

- Drafts appear in **My Inspections** with a blue "Draft" badge.
- Swipe-left on a draft reveals a Delete action (confirmation required). Deletion removes the draft, all its `PendingPhoto` records, local photo files, and associated `LocalIssue` records.
- Only `status == "draft"` inspections may be deleted.

### Status badge map

| `status` | `syncStatus` | Badge label | Badge colour |
|---|---|---|---|
| `draft` | any | Draft | Blue |
| `completed` | `pending` | Pending Sync | Orange |
| `completed` | `synced` | Completed | Green |
| `failed` | any | Sync Failed | Red |

---

## 12. Form Field Rendering

### GridFormView (primary renderer in ExecuteInspectionView)

Uses a 12-column absolute-position grid matching the web app's CSS grid exactly:

| Constant | Value | Source |
|---|---|---|
| `totalColumns` | 12 | Web editor `COLS=12` |
| `cellGap` | 8 pt | Web CSS `col-gap: 8px` |
| `rowGap` | 4 pt | Web CSS `row-gap: 4px` |
| `cellAspect` | 52/72 | Web editor `CELL_H/CELL_W` |
| `cardPadding` | 16 pt | Card inset |

Cell position is computed from `col`, `row`, `colSpan`, `rowSpan` attributes in the field schema. Container width is measured via a `PreferenceKey` pattern (zero-height overlay with `GeometryReader`) — works correctly through rotations and split-screen resizing.

### Supported field types

| Type | SwiftUI renderer |
|---|---|
| `text`, `email` | `TextField` |
| `textarea` | `TextEditor` |
| `number` | `TextField` + `.decimalPad` |
| `date` | `DatePicker` (date only) |
| `checkbox` | `Toggle` |
| `checkbox_group` | Custom multi-select buttons (`CellCheckboxGroup`) |
| `radio` | Custom radio buttons (`CellRadioGroup`) |
| `select` | `Menu` dropdown (`CellSelect`) |
| `rating` | Custom star row (`CellRatingStars`) — tap same star to clear |
| `pass_fail` | Capsule pill buttons (`CellPassFail`) — tap selected to deselect |
| `signature` | `PKCanvasView` (`SignatureFieldView`) — requires PencilKit framework |
| `image` | `CompactImageFieldView` (grid) / `ImageFieldView` (standalone) |
| `table` | `TableFieldView` — horizontal scroll, editable cells |
| `section`, `label` | Display-only `Text` |

### Field ID rule (CRITICAL)

Form schema IDs from the server are **integers** in JSON (e.g. `"id": 5`). After `JSONSerialization`, they arrive as `Int` in `[String: Any]` dictionaries. `formData` keys are always `String`. Field IDs must be resolved via:

```swift
let fid: String
if let s = field["id"] as? String { fid = s }
else if let n = field["id"] as? Int { fid = String(n) }
else { continue }
```

**Never use `Optional.map` on `field["id"]`** — it produces `"Optional(5)"` instead of `"5"`, causing all formData lookups to silently miss and all scores to return 0.

---

## 13. Issue Flagging Workflow

`FlagIssueView` is presented as a sheet from `ExecuteInspectionView`.

1. Inspector selects severity (segmented control: low / medium / high / critical).
2. Enters description (required).
3. Optionally attaches a photo.
4. Tapping Submit:
   - Creates `LocalIssue` with `facilityServerId` from the parent inspection.
   - Appends the issue to `inspection.localIssues`.
   - If a photo was taken: creates a `PendingPhoto` with `entityType = "issue"`.
   - Saves to SwiftData.
   - Shows a green **"Issue Logged"** confirmation banner (2 seconds) then dismisses.
   - Triggers `SyncManager.triggerSync()` if online.
5. Area picker is absent — facility is derived directly from the inspection context.

### Issue sync guard

If `inspection.syncStatus == "failed"` when `processIssueQueue` runs, the issue is immediately marked `"failed"` with message `"Parent inspection failed to sync — issue cannot be submitted."` This prevents orphaned server records with no `inspection_id`.

---

## 14. Re-inspection Workflow

### Trigger

On `CompletedInspectionView`, if `inspection.followUpRequired == true`, an orange banner is shown with a **Start Re-inspection** button. This opens `StartInspectionView` with `preFillTemplateId`, `preFillFacilityId`, `parentServerId`, and `parentLocalId` pre-set.

### Parent form pre-fill

`StartInspectionView.startInspection()` copies non-scoring fields from the parent's `formData` into the new inspection. Excluded field types: `rating`, `pass_fail`, `image`, `signature` — these must always be re-evaluated fresh.

### Picker pre-fill (template, contract, facility)

`applyPreFill()` sets `selectedTemplateId`, `selectedProjectId`, and `selectedFacilityId` on `.onAppear`. **The `.onChange(of: selectedProjectId)` handler guards against resetting `selectedFacilityId`** when the facility already belongs to the newly selected contract — this prevents the onChange from wiping the pre-filled facility before it renders. Without this guard, `selectedProjectId` is set first, `.onChange` fires, and `selectedFacilityId` is reset to `nil` before it can be applied.

### followUpRequired clearing

Cleared at **three** points to ensure the badge disappears regardless of timing:

1. **Immediately on Submit** in `ExecuteInspectionView.submitInspection()` via `clearParentFollowUpFlag()`.
2. **After sync** in `SyncManager.processInspectionQueue` using `parentLocalId`.
3. **On the server** in `api/inspections.py` when the PATCH/POST arrives.

`clearParentFollowUpFlag()` resolution order:
1. Match by `parentLocalId` (UUID, always set if re-inspection was created in this session).
2. Fall back to `parentServerId` (set only after parent has synced).
3. Last resort: match by same `templateServerId + facilityServerId + followUpRequired == true`. **This fallback is ambiguous when multiple follow-ups are pending for the same template/facility combination.**

---

## 15. Inspection History

`InspectionHistoryView` fetches completed inspections from the server via `GET /api/v1/inspections?status=completed`. It is **online-only** — shows `ContentUnavailableView` with "Offline" when `!sync.isOnline`.

Pagination: limit 30, offset-based. A "Load More" button appears when `inspections.count < total`. Pull-to-refresh resets to page 0.

---

## 16. Photo Handling

### Capture

Photos are taken via `UIImagePickerController` (camera) or `PHPickerViewController` (library, no permission required for iOS 16+).

### Local storage

All photos are saved to: `Documents/JQC/Photos/<UUID>.jpg` at JPEG quality 0.8.

### PendingPhoto lifecycle

```
Created (uploadStatus="pending")
    ↓ SyncManager.processPhotoQueue()
Uploaded (uploadStatus="uploaded", serverPath set)
    ↓ Parent record updated
    For inspection image fields: LocalInspection.formData[fieldId] = serverPath
    For issues: LocalIssue.photoServerPath = serverPath
```

### local:// sentinel

While a photo is pending upload, the form field value is set to `"local://<path>"`. Before `submitInspection` sends `formData` to the server, these values are replaced with `""`. A `local://` value that reaches the server would be stored as a malformed path.

### Server-hosted photos in IssueDetailView

`IssueDetailView` shows two photo sections:
1. **Local photos** — `photoLocalPaths` rendered via `UIImage(contentsOfFile:)`. Present for device-created issues where photos were captured on-device.
2. **Server photos** — `photoServerPaths` rendered via `AsyncImage(url: Constants.baseURL + "/" + relativePath)`. Present for issues pulled from the server (`pullAssignedIssues` stores `photo_path` + `result_photos` from the API response into `photoServerPaths`).

Both sections are shown independently; an issue can have entries in either or both.

---

## 17. Score Calculation

`LocalInspection.computeScore(fromSchema:)` mirrors Python's `_compute_score_from_form()` exactly.

**Scoreable field types:** `rating`, `checkbox`, `radio`, `pass_fail`.

| Type | Rule |
|---|---|
| `rating` | Value `0` = unanswered → excluded. Each answered rating contributes `value / 5` of a possible 1.0 |
| `checkbox` | `"true"` = pass, anything else = fail |
| `radio` | Pass keywords: `pass`, `yes`, `ok`, `good`, `acceptable`, `compliant` (case-insensitive) |
| `pass_fail` | Same pass keywords as radio. Empty string = unanswered → excluded |

Returns `nil` if no scoreable fields or all are unanswered.

**Field ID resolution:** Always use the explicit cast pattern (see §12). `Optional.map` on `Any?` produces `"Optional(5)"` — all lookups miss, all scores return 0.

---

## 18. Background Sync

The app registers a `BGProcessingTask` with identifier `com.jqc.sync`.

**`Info.plist` requirement:** `BGTaskSchedulerPermittedIdentifiers` must contain `com.jqc.sync`. Without this entry, `BGTaskScheduler.shared.register` silently fails and background sync never fires.

**Note on `GENERATE_INFOPLIST_FILE`:** The project uses `GENERATE_INFOPLIST_FILE = YES`. Do NOT also have a physical `Info.plist` file on disk — having both causes "Multiple commands produce Info" build error. The file is generated at build time; there is no `Info.plist` in the source tree.

**Scheduling:** `scheduleBackgroundSync()` is called:
- Every time `scenePhase == .background`
- At the start of each background task handler (schedules the next run)

**Requirements:** `requiresNetworkConnectivity = true`, `requiresExternalPower = false`.

**Tokens:** Keychain access policy `kSecAttrAccessibleAfterFirstUnlock` ensures tokens are available when the app is woken by BGTaskScheduler after device reboot.

---

## 19. Settings & Cache Management

`SettingsView` exposes:
- Account info (username, role) — read-only from `AuthManager`.
- **Sync Now** — triggers `SyncManager.triggerSync()`; disabled when offline or already syncing.
- Last sync timestamp.
- **Clear Reference Cache** — deletes all `LocalFacility`, `LocalArea`, and `LocalTemplate` records. **Never deletes `LocalInspection`, `LocalIssue`, or `PendingPhoto`.** Triggers `pullReferenceData()` immediately if online.
- **Log Out** — calls `AuthManager.logout()`.
- App version and server URL (from `Constants.baseURL`).

---

## 20. Known Constraints & Hard Rules

| # | Rule | Rationale |
|---|---|---|
| 1 | **`import Combine` required in files using `@Published`** | Swift 5.9+ does not auto-import Combine; `ObservableObject` without it causes build errors |
| 2 | **No `selection:` binding on `NavigationSplitView`** | `init(selection:content:)` unavailable on iPadOS 17; use `@State var selectedTab: SidebarTab` with `Button` handlers |
| 3 | **No `#Predicate` anywhere in `SyncManager`** | Under Xcode 26 `SWIFT_DEFAULT_ACTOR_ISOLATION = MainActor`, `#Predicate` with a captured String variable causes `LocalInspection is ambiguous` compiler cascade. Use fetch-all + filter in Swift throughout |
| 4 | **Sequential `await` in `pullReferenceData()`** | `async let` causes Swift 6 actor-isolation warnings on `Decodable` structs; use sequential `await` calls |
| 5 | **PencilKit requires explicit framework linkage** | Add `PencilKit.framework` under Target → Frameworks, Libraries, and Embedded Content |
| 6 | **Free Apple ID provisioning expires every 7 days** | Rebuild with ⌘R while iPad is connected; SwiftData persists across reinstalls |
| 7 | **`kSecAttrAccessibleAfterFirstUnlock` for all Keychain items** | Tokens must be readable when the app is woken by BGTaskScheduler after reboot |
| 8 | **New `Bool` model fields require `= false` default** | SwiftData lightweight migration crashes on launch without a default value for new Bool properties |
| 9 | **Field IDs in formData are always String keys** | Server encodes them as Int in JSON; always cast via `as? String` then `as? Int → String(n)`. Never use `Optional.map` on `field["id"]` |
| 10 | **Strip `local://` paths from formData before `submitInspection`** | Failed photo uploads leave `"local://..."` in formData; JSONSerialization silently drops non-serialisable values |
| 11 | **Do not submit an issue when parent inspection `syncStatus == "failed"`** | Submitting with no `inspection_id` creates orphaned server records |
| 12 | **Photo-before-inspection ordering in sync** | `processPhotoQueue` must run before `processInspectionQueue` |
| 13 | **`com.jqc.sync` must be in BGTaskSchedulerPermittedIdentifiers** | BGTaskScheduler silently ignores unregistered identifiers |
| 14 | **`refreshAccessToken()` uses a local JSONDecoder, not `self.decoder`** | Accessing the actor-isolated `self.decoder` from a non-isolated context triggers Swift 6 isolation errors |
| 15 | **`clearParentFollowUpFlag()` fallback-2 is ambiguous** | Matching by template+facility is ambiguous when multiple follow-ups are pending for the same template/facility |
| 16 | **`SyncQueueEntry` model is registered but not actively written** | Included for future use; `syncStatus` on `LocalInspection` and `LocalIssue` is the active queue |
| 17 | **`Constants.baseURL` is the only server URL** | All endpoints are `Constants.baseURL + endpoint`. Update this one constant for environment changes |
| 18 | **Photo JPEG compression is 0.8** | Do not raise above 0.85 without testing against the server's 50 MB limit |
| 19 | **`clearCache()` in Settings never deletes inspections or issues** | Only `LocalFacility`, `LocalArea`, `LocalTemplate` are safe to purge |
| 20 | **`AuthManager.restoreSession()` falls back to Keychain on non-auth errors** | Allows offline launch but may expose stale role/identity data |
| 21 | **`startMonitoring()` must be called AFTER `restoreSession()` completes** | NWPathMonitor fires immediately on launch, triggering `triggerSync()` before tokens exist; the 401 loop leaves `isLoading` stuck |
| 22 | **`triggerSync()` guards on `AuthManager.shared.isAuthenticated`** | Prevents sync from running before auth is established — covers the NWPathMonitor race and any BGTask path |
| 23 | **Do NOT place model files in non-Model folders** | Xcode 26 folder sync compiles every `.swift` in the tree; a `LocalInspection.swift` in `Auth/` causes "Multiple commands produce LocalInspection" |
| 24 | **No physical `Info.plist` file when `GENERATE_INFOPLIST_FILE = YES`** | Having both causes "Multiple commands produce Info" build error |
| 25 | **Always parenthesise `try?` before `??`** | `try? context.fetch(...) ?? []` parses as `try? (fetch() ?? [])` — `fetch()` is non-optional so `??` is invalid inside `try?`; compiler infers `T = Any` and cascades into build errors. Write `(try? context.fetch(...)) ?? []` |
| 26 | **Delete Xcode's default `Item.swift` immediately after project creation** | Xcode generates `Item.swift` with `@Model class Item` when creating a new SwiftData project; it compiles silently via folder sync and conflicts with real models |
| 27 | **`Timer.scheduledTimer` must NOT be used for periodic work in SyncManager** | Inside `Task { @MainActor }`, `RunLoop.current` ≠ `RunLoop.main`; the timer is added to a runloop that never ticks and fires silently never. Use `Task.sleep` instead |
| 28 | **`UNUserNotificationCenterDelegate` must be set for foreground notifications** | Without a delegate returning `[.banner, .sound]` from `willPresent`, iOS silently drops local notifications while the app is active. `NotificationDelegate.shared` is set in `JanitorialQCApp.init()` |
| 29 | **All `Decodable & Sendable` response structs need `nonisolated init(from:)`** | Under `SWIFT_DEFAULT_ACTOR_ISOLATION = MainActor`, synthesised Decodable inits inherit `@MainActor` isolation, conflicting with the `Sendable` constraint on `_Envelope<T>`; every API model struct must declare `nonisolated init(from decoder: any Decoder)` explicitly |
| 30 | **`pullAssignedIssues` deletion pass must NOT be short-circuited on empty response** | If the server returns zero issues (all unassigned), the deletion pass must still run to remove stale local records; do not `guard !apiIssues.isEmpty else { return }` before the deletion loop |
| 31 | **Server-pulled issues identified by `syncStatus == "synced"` + `inspectionLocalId == ""`** | These are the only records safe to delete during reconciliation. Device-created issues have `inspectionLocalId != ""` and must never be deleted by `pullAssignedIssues` |
| 32 | **`StartInspectionView.onChange(of: selectedProjectId)` guards against resetting pre-filled facility** | Check `facilityBelongsToContract` before clearing `selectedFacilityId`; the onChange fires during `applyPreFill()` before `selectedFacilityId` is applied, wiping it if unchecked |
| 33 | **Issue photos are stored in `photoServerPaths` after `pullAssignedIssues`** | `photo_path` and `result_photos` from `_issue_payload` are merged into a single `[String]` and stored in `local.photoServerPaths` on insert/update |
| 34 | **`IssueDetailView` shows both `photoLocalPaths` and `photoServerPaths`** | Local paths use `UIImage(contentsOfFile:)`; server paths use `AsyncImage` with `Constants.baseURL` prefix. Both sections are independent |
| 35 | **`SyncManager.isoFormatter` is the only date formatter — never allocate per-call** | `DateFormatter` init is expensive. The static `nonisolated` formatter with `en_US_POSIX` locale handles all `yyyy-MM-dd'T'HH:mm:ss` parsing. Adding a new `DateFormatter` anywhere in SyncManager is wrong. |
| 36 | **`uploadPhoto(retrying:)` — pass `retrying: true` on recursive retry** | Matches `request()` pattern. Without it, a 401 on the retry triggers a second token refresh instead of throwing `notAuthenticated`. |
| 37 | **`LocalIssue.inspection` must declare explicit `@Relationship` inverse** | `@Relationship(deleteRule: .nullify, inverse: \LocalInspection.localIssues)` — without it SwiftData infers the inverse implicitly, which can produce migration warnings and incorrect cascade behaviour under some Xcode 26 versions. `deleteRule` is `.nullify` not `.cascade` because cascade is already declared on `LocalInspection.localIssues`. |
| 38 | **`APIUser.displayName` uses `fullName` when non-empty, falls back to `username`** | Server `_user_payload` sends `full_name`; iOS decodes as `fullName: String` (empty string when unset). `displayName` computed property: `fullName.isEmpty ? username : fullName`. Mirrors `User.display_name` server-side. |

---

## 21. Xcode 26 Specific Issues

This project was created with **Xcode 26.4.1** (Apple's major 2026 release). Several compiler behaviours differ from Xcode 15/16 and require specific patterns.

### SWIFT_DEFAULT_ACTOR_ISOLATION = MainActor

Xcode 26 sets this build setting when creating new projects with "approachable concurrency" enabled. It makes every type and function implicitly `@MainActor`.

**Effect on SwiftData:** SwiftData's `@Model` macro generates `nonisolated` accessors internally. When `FetchDescriptor<LocalInspection>` is used inside a `@MainActor` async method, the compiler sees a conflict between `@MainActor LocalInspection` and `nonisolated PersistentModel` requirements. The error cascade is:
- `'LocalInspection' is ambiguous for type lookup in this context`
- `Generic parameter 'T' could not be inferred`
- `Type 'Any' cannot conform to 'PersistentModel'`
- `The compiler is unable to type-check this expression in reasonable time`

**Solutions applied in this codebase:**
1. All `context.fetch()` calls use fetch-all + filter in Swift — no `#Predicate` with captured variables.
2. All `try? context.fetch(...)` expressions are parenthesised before `??`.
3. Chained optional patterns `(try? fetch(...))?.filter { }` are split into two `let` statements.
4. `triggerSync()` guards on `isAuthenticated` to prevent 401 cascades during startup.
5. Notification polling uses `Task.sleep` not `Timer.scheduledTimer` (RunLoop dependency).
6. All API model structs declare `nonisolated init(from decoder: any Decoder)` explicitly — including file-scope `private` structs like `_RefreshEnvelope` in `APIClient.swift`. A `private` struct defined in a file containing an `actor` or `@MainActor` type can have its `Decodable` conformance tainted with `@MainActor`, producing "cannot be used in actor-isolated context" errors in Swift 6 mode. The fix is always an explicit `nonisolated init(from:)` with a matching `CodingKeys` enum.

**Do NOT remove `SWIFT_DEFAULT_ACTOR_ISOLATION = MainActor` from build settings** unless you fully audit every file for the resulting isolation changes. The patterns above are the correct workarounds.

### PBXFileSystemSynchronizedRootGroup (Folder Sync)

Xcode 26 uses folder-sync mode instead of an explicit file list in `project.pbxproj`. **Every `.swift` file in the project folder is compiled automatically.** There is no file registry to check.

Consequences:
- Stray files (e.g. `Item.swift` from the project template, accidentally duplicated model files) compile silently and cause "Multiple commands produce" errors.
- Deleting a file from Finder is sufficient to remove it from the build — no need to remove it from the project navigator separately.
- When diagnosing "Multiple commands produce X", run: `find /path/to/project -name "*.swift" | xargs grep -l "class X"` to find all definitions.

### Derived Data corruption

Under Xcode 26, repeated failed builds accumulate corrupt intermediate files in derived data. After any "Multiple commands produce" error is resolved, delete derived data manually before rebuilding:

```bash
rm -rf ~/Library/Developer/Xcode/DerivedData/<ProjectName>-<hash>
```

The hash is visible in every error message path. Do not use Product → Clean Build Folder alone — it does not remove all intermediate files.

---

## 22. Change Philosophy

1. **Read the actual file before editing.** Never rely on earlier context — a prior edit invalidates it. When a user pastes file content, that is the ground truth — not the local copy.
2. **Trace the full data path.** For any bug: view → SwiftData write → SyncManager → APIClient → server response. Identify the exact layer.
3. **Root cause, not symptom.** State the root cause explicitly before proposing a fix. Multiple failed attempts are always caused by treating symptoms.
4. **Smallest possible change.** Do not restructure, rename, or reformat surrounding code.
5. **Never remove functionality** unless explicitly directed.
6. **SwiftData schema changes need defaults.** All new `Bool` fields: `= false`. Run on device and check for migration crash before shipping.
7. **Test offline and online.** Every sync-related fix must be verified in airplane mode.
8. **Verify file placement.** After delivering a file, confirm the user placed it at the correct path. Xcode 26 folder sync means a file in the wrong subfolder compiles as a duplicate.
9. **When errors persist unchanged across multiple fix attempts, the file is not being picked up.** Ask the user to paste the current file content before making further changes.
10. **Update this document** at the end of any session that introduces a new constraint, model field, sync rule, or architectural decision.