axiom-photo-library

# Photo Library Access with PhotoKit

Guides you through photo picking, limited library handling, and saving photos to the camera roll using privacy-forward patterns.

## When to Use This Skill

Use when you need to:
- ☑ Let users select photos from their library
- ☑ Handle limited photo library access
- ☑ Save photos/videos to the camera roll
- ☑ Choose between PHPicker and PhotosPicker
- ☑ Load images from PhotosPickerItem
- ☑ Observe photo library changes
- ☑ Request appropriate permission level

## Example Prompts

"How do I let users pick photos in SwiftUI?"
"User says they can't see their photos"
"How do I save a photo to the camera roll?"
"What's the difference between PHPicker and PhotosPicker?"
"How do I handle limited photo access?"
"User granted limited access but can't see photos"
"How do I load an image from PhotosPickerItem?"

## Red Flags

Signs you're making this harder than it needs to be:

- ❌ Using UIImagePickerController (deprecated for photo selection)
- ❌ Requesting full library access when picker suffices (privacy violation)
- ❌ Ignoring `.limited` authorization status (users can't expand selection)
- ❌ Not handling Transferable loading failures (crashes on large photos)
- ❌ Synchronously loading images from picker results (blocks UI)
- ❌ Using PhotoKit APIs when you only need to pick photos (over-engineering)
- ❌ Assuming `.authorized` after user grants access (could be `.limited`)

## Mandatory First Steps

Before implementing photo library features:

### 1. Choose Your Approach

```
What do you need?

┌─ User picks photos (no library browsing)?
│  ├─ SwiftUI app → PhotosPicker (iOS 16+)
│  └─ UIKit app → PHPickerViewController (iOS 14+)
│  └─ NO library permission needed! Picker handles it.
│
├─ Display user's full photo library (gallery UI)?
│  └─ Requires PHPhotoLibrary authorization
│     └─ Request .readWrite for browsing
│     └─ Handle .limited status with presentLimitedLibraryPicker
│
├─ Save photos to camera roll?
│  └─ Requires PHP