// Label: the primary description VoiceOver reads
Button(action: { }) {
    Image(systemName: "heart.fill")
}
.accessibilityLabel("Favorite")

// Hint: describes the result of activation (read after a pause)
Button("Submit")
    .accessibilityHint("Submits the form and sends your feedback")

// Value: the current state for sliders, toggles, progress indicators
Slider(value: $volume, in: 0...100)
    .accessibilityValue("\(Int(volume)) percent")

Button("Go") { }
    .accessibilityInputLabels(["Go", "Start", "Begin"])

// WRONG: overwrites Button's built-in .isButton trait
Button("Go") { }
    .accessibilityTraits(.updatesFrequently)

// CORRECT: adds to existing traits
Button("Go") { }
    .accessibilityAddTraits(.updatesFrequently)

// Remove a trait when needed
Text("Not really a header anymore")
    .accessibilityRemoveTraits(.isHeader)

// .combine: merge children into one VoiceOver element
// VoiceOver concatenates child labels automatically
HStack {
    Image(systemName: "person.circle")
    VStack {
        Text("John Doe")
        Text("Engineer")
    }
}
.accessibilityElement(children: .combine)

// .ignore: replace children with a completely custom label
HStack {
    Image(systemName: "envelope")
    Text("inbox@example.com")
}
.accessibilityElement(children: .ignore)
.accessibilityLabel("Email: inbox@example.com")

// .contain: keep children individually navigable but logically grouped
VStack {
    Text("Order #1234")
    Button("Track") { }
}
.accessibilityElement(children: .contain)

HStack {
    Text("Dark Mode")
    Circle()
        .fill(isDark ? .green : .gray)
        .onTapGesture { isDark.toggle() }
}
.accessibilityRepresentation {
    Toggle("Dark Mode", isOn: $isDark)
}

// Custom slider control
VStack {
    SliderTrack(value: value) // Custom visual implementation
}
.accessibilityRepresentation {
    Slider(value: $value, in: 0...100) {
        Text("Volume")
    }
}

HStack { /* custom star rating UI */ }
    .accessibilityElement()
    .accessibilityLabel("Rating")
    .accessibilityValue("\(rating) out of 5 stars")
    .accessibilityAdjustableAction { direction in
        switch direction {
        case .increment: if rating < 5 { rating += 1 }
        case .decrement: if rating > 1 { rating -= 1 }
        @unknown default: break
        }
    }

MessageRow(message: message)
    .accessibilityAction(named: "Reply") { reply(to: message) }
    .accessibilityAction(named: "Delete") { delete(message) }
    .accessibilityAction(named: "Flag") { flag(message) }

PlayerView()
    .accessibilityAction(.magicTap) { togglePlayPause() }
    .accessibilityAction(.escape) { dismiss() }

ZStack {
    Image("photo").accessibilitySortPriority(0)     // Read third
    Text("Credit").accessibilitySortPriority(1)      // Read second
    Text("Breaking News").accessibilitySortPriority(2) // Read first
}

struct ContentView: View {
    @State private var showSheet = false
    @AccessibilityFocusState private var focusOnTrigger: Bool

    var body: some View {
        Button("Open Settings") { showSheet = true }
            .accessibilityFocused($focusOnTrigger)
            .sheet(isPresented: $showSheet) {
                SettingsSheet()
                    .onDisappear {
                        // Slight delay allows the transition to complete before moving focus
                        Task { @MainActor in
                            try? await Task.sleep(for: .milliseconds(100))
                            focusOnTrigger = true
                        }
                    }
            }
    }
}

enum A11yFocus: Hashable {
    case nameField
    case emailField
    case submitButton
}

struct FormView: View {
    @AccessibilityFocusState private var focus: A11yFocus?

    var body: some View {
        Form {
            TextField("Name", text: $name)
                .accessibilityFocused($focus, equals: .nameField)
            TextField("Email", text: $email)
                .accessibilityFocused($focus, equals: .emailField)
            Button("Submit") { validate() }
                .accessibilityFocused($focus, equals: .submitButton)
        }
    }

    func validate() {
        if name.isEmpty {
            focus = .nameField // Move VoiceOver to the invalid field
        }
    }
}

CustomDialog()
    .accessibilityAddTraits(.isModal)
    .accessibilityAction(.escape) { dismiss() }

// Announce a status change (e.g., "Item deleted", "Upload complete")
UIAccessibility.post(notification: .announcement, argument: "Upload complete")

// Partial screen update -- move focus to a specific element
UIAccessibility.post(notification: .layoutChanged, argument: targetView)

// Full screen transition -- move focus to the new screen
UIAccessibility.post(notification: .screenChanged, argument: newScreenView)

@ScaledMetric(relativeTo: .title) private var iconSize: CGFloat = 24
@ScaledMetric private var spacing: CGFloat = 8

var body: some View {
    HStack(spacing: spacing) {
        Image(systemName: "star.fill")
            .frame(width: iconSize, height: iconSize)
        Text("Favorite")
    }
}

@Environment(\.dynamicTypeSize) var dynamicTypeSize

var body: some View {
    if dynamicTypeSize.isAccessibilitySize {
        VStack(alignment: .leading) { icon; textContent }
    } else {
        HStack { icon; textContent }
    }
}

Button(action: { }) {
    Image(systemName: "plus")
        .frame(minWidth: 44, minHeight: 44)
}
.contentShape(Rectangle())

List(items) { item in
    ItemRow(item: item)
}
.accessibilityRotor("Unread") {
    ForEach(items.filter { !$0.isRead }) { item in
        AccessibilityRotorEntry(item.title, id: item.id)
    }
}
.accessibilityRotor("Flagged") {
    ForEach(items.filter { $0.isFlagged }) { item in
        AccessibilityRotorEntry(item.title, id: item.id)
    }
}

@Environment(\.accessibilityReduceMotion) var reduceMotion
@Environment(\.accessibilityReduceTransparency) var reduceTransparency
@Environment(\.colorSchemeContrast) var contrast         // .standard or .increased
@Environment(\.legibilityWeight) var legibilityWeight    // .regular or .bold

withAnimation(reduceMotion ? nil : .spring()) {
    showContent.toggle()
}
content.transition(reduceMotion ? .opacity : .slide)

// Solid backgrounds when transparency is reduced
.background(reduceTransparency ? Color(.systemBackground) : Color(.systemBackground).opacity(0.85))

// Stronger colors when contrast is increased
.foregroundStyle(contrast == .increased ? .primary : .secondary)

// Bold weight when system bold text is enabled
.fontWeight(legibilityWeight == .bold ? .bold : .regular)

// Decorative images: hidden from VoiceOver
Image(decorative: "background-pattern")
Image("visual-divider").accessibilityHidden(true)

// Icon next to text: Label handles this automatically
Label("Settings", systemImage: "gear")

// Icon-only buttons: MUST have an accessibility label
Button(action: { }) {
    Image(systemName: "gear")
}
.accessibilityLabel("Settings")

// UIKit trait modification
customButton.accessibilityTraits.insert(.button)
customButton.accessibilityTraits.remove(.staticText)

// Modal overlay
overlayView.accessibilityViewIsModal = true

ProductRow(product: product)
    .accessibilityCustomContent("Price", product.formattedPrice)
    .accessibilityCustomContent("Rating", "\(product.rating) out of 5")
    .accessibilityCustomContent(
        "Availability",
        product.inStock ? "In stock" : "Out of stock",
        importance: .high  // .high reads automatically with the element
    )