Add an iPhone client sharing the macOS app's SwiftUI code

mac/Sources/Byre/MarkdownView.swift

@@ -206,17 +206,28 @@ struct InlineRenderer {
     private func run(_ s: String, _ style: Style) -> AttributedString {
         var a = AttributedString(s)
         a.font = Fonts.font(style.small ? 11 : size, weight: style.bold ? 700 : weight, italic: style.italic, mono: style.mono)
-        a.mergeAttributes(try! AttributeContainer([.font: Fonts.ns(style.small ? 11 : size, weight: style.bold ? 700 : weight, italic: style.italic, mono: style.mono)], including: \.appKit))
+        let font = Fonts.native(style.small ? 11 : size, weight: style.bold ? 700 : weight, italic: style.italic, mono: style.mono)
+        #if os(macOS)
+        a.mergeAttributes(try! AttributeContainer([.font: font], including: \.appKit))
+        #else
+        a.uiKit.font = font
+        #endif
         if let link = style.link {
             a.link = link
         }
         if let color = style.color {
             a.foregroundColor = color
+            #if os(macOS)
             a.appKit.foregroundColor = NSColor(color)
+            #else
+            a.uiKit.foregroundColor = UIColor(color)
+            #endif
         }
+        #if os(macOS)
         if let tip = style.tip {
             a.appKit.toolTip = tip
         }
+        #endif
         return a
     }
 
@@ -244,7 +255,11 @@ struct InlineRenderer {
                 }
                 var a = run(c, s)
                 a.backgroundColor = Palette.surface
+                #if os(macOS)
                 a.appKit.backgroundColor = NSColor(Palette.surface)
+                #else
+                a.uiKit.backgroundColor = UIColor(Palette.surface)
+                #endif
                 append(a, &out)
             case .strong(let inner):
                 var s = style
@@ -410,7 +425,15 @@ struct InlineRenderer {
     }
 }
 
-private func flowColor(_ s: NSMutableAttributedString, _ color: NSColor) {
+private func nativeString(_ a: AttributedString) -> NSAttributedString {
+    #if os(macOS)
+    try! NSAttributedString(a, including: \.appKit)
+    #else
+    try! NSAttributedString(a, including: \.uiKit)
+    #endif
+}
+
+private func flowColor(_ s: NSMutableAttributedString, _ color: PlatformColor) {
     let all = NSRange(location: 0, length: s.length)
     unsafe s.enumerateAttribute(.foregroundColor, in: all) { value, range, _ in
         if value == nil {
@@ -543,7 +566,7 @@ private struct FlowBuilder {
             gap += 4
             para(inline([.strong(inlines)], level == 3 ? 14 : 13), indent, indent)
         case .list(let ordered, let start, let items, _):
-            let font = Fonts.ns(ctx.size)
+            let font = Fonts.native(ctx.size)
             for (n, item) in items.enumerated() {
                 if n > 0 {
                     gap = 2
@@ -563,14 +586,14 @@ private struct FlowBuilder {
 
     private func inline(_ inlines: [MDInline], _ size: CGFloat) -> NSAttributedString {
         let a = InlineRenderer(store: store, size: size, taskId: ctx.taskId, weight: ctx.weight, dir: ctx.dir).text(inlines)
-        return try! NSAttributedString(a, including: \.appKit)
+        return nativeString(a)
     }
 
     private mutating func para(_ a: NSAttributedString, _ first: CGFloat, _ head: CGFloat) {
         let s = NSMutableAttributedString(attributedString: a)
-        s.append(NSAttributedString(string: "\n", attributes: [.font: Fonts.ns(ctx.size)]))
+        s.append(NSAttributedString(string: "\n", attributes: [.font: Fonts.native(ctx.size)]))
         let all = NSRange(location: 0, length: s.length)
-        flowColor(s, NSColor(ctx.color))
+        flowColor(s, PlatformColor(ctx.color))
         let lead = (s.string as NSString).range(of: "\n").location + 1
         s.addAttribute(.paragraphStyle, value: style(first, head, 0), range: all)
         s.addAttribute(.paragraphStyle, value: style(first, head, gap), range: NSRange(location: 0, length: lead))
@@ -589,6 +612,36 @@ private struct FlowBuilder {
     }
 }
 
+private final class FlowMeasure {
+    private let storage = NSTextStorage()
+    private let layout = NSLayoutManager()
+    private let container = NSTextContainer()
+    private var measured: (text: NSAttributedString, width: CGFloat?, size: CGSize)?
+
+    init() {
+        container.lineFragmentPadding = 0
+        layout.addTextContainer(container)
+        storage.addLayoutManager(layout)
+    }
+
+    func size(_ text: NSAttributedString, _ width: CGFloat?) -> CGSize {
+        let same = measured.map { $0.text === text || $0.text.isEqual(to: text) } ?? false
+        if same, let m = measured, m.width == width {
+            return m.size
+        }
+        if !same {
+            storage.setAttributedString(text)
+        }
+        container.size = CGSize(width: width ?? .greatestFiniteMagnitude, height: .greatestFiniteMagnitude)
+        layout.ensureLayout(for: container)
+        let used = layout.usedRect(for: container)
+        let size = CGSize(width: width ?? ceil(used.width), height: ceil(used.height))
+        measured = (text, width, size)
+        return size
+    }
+}
+
+#if os(macOS)
 private final class FlowTextView: NSTextView {
     var onTap: (@MainActor @Sendable () -> Void)?
     let storage: NSTextStorage
@@ -702,32 +755,10 @@ private struct FlowText: NSViewRepresentable {
 
     final class Coordinator: NSObject, NSTextViewDelegate {
         var openURL: OpenURLAction?
-        private let storage = NSTextStorage()
-        private let layout = NSLayoutManager()
-        private let container = NSTextContainer()
-        private var measured: (text: NSAttributedString, width: CGFloat?, size: CGSize)?
-
-        override init() {
-            super.init()
-            container.lineFragmentPadding = 0
-            layout.addTextContainer(container)
-            storage.addLayoutManager(layout)
-        }
+        private let measure = FlowMeasure()
 
         func size(_ text: NSAttributedString, _ width: CGFloat?) -> CGSize {
-            let same = measured.map { $0.text === text || $0.text.isEqual(to: text) } ?? false
-            if same, let m = measured, m.width == width {
-                return m.size
-            }
-            if !same {
-                storage.setAttributedString(text)
-            }
-            container.size = CGSize(width: width ?? .greatestFiniteMagnitude, height: .greatestFiniteMagnitude)
-            layout.ensureLayout(for: container)
-            let used = layout.usedRect(for: container)
-            let size = CGSize(width: width ?? ceil(used.width), height: ceil(used.height))
-            measured = (text, width, size)
-            return size
+            measure.size(text, width)
         }
 
         func textView(_ textView: NSTextView, clickedOnLink link: Any, at charIndex: Int) -> Bool {
@@ -739,6 +770,113 @@ private struct FlowText: NSViewRepresentable {
         }
     }
 }
+#else
+private final class FlowTextView: UITextView {
+    var onTap: (@MainActor @Sendable () -> Void)?
+    let storage: NSTextStorage
+
+    init() {
+        let storage = NSTextStorage()
+        let layout = NSLayoutManager()
+        let container = NSTextContainer(size: CGSize(width: 0, height: CGFloat.greatestFiniteMagnitude))
+        container.lineFragmentPadding = 0
+        container.widthTracksTextView = true
+        storage.addLayoutManager(layout)
+        layout.addTextContainer(container)
+        self.storage = storage
+        super.init(frame: .zero, textContainer: container)
+        isEditable = false
+        isSelectable = true
+        isScrollEnabled = false
+        backgroundColor = .clear
+        textContainerInset = .zero
+        linkTextAttributes = [:]
+    }
+
+    required init?(coder: NSCoder) {
+        fatalError("init(coder:) is not supported")
+    }
+
+    func link(at point: CGPoint) -> Bool {
+        guard storage.length > 0 else {
+            return false
+        }
+        let p = CGPoint(x: point.x - textContainerInset.left, y: point.y - textContainerInset.top)
+        let g = layoutManager.glyphIndex(for: p, in: textContainer)
+        if !layoutManager.boundingRect(forGlyphRange: NSRange(location: g, length: 1), in: textContainer).contains(p) {
+            return false
+        }
+        let i = layoutManager.characterIndexForGlyph(at: g)
+        if i >= storage.length {
+            return false
+        }
+        return unsafe storage.attribute(.link, at: i, effectiveRange: nil) != nil
+    }
+}
+
+private struct FlowText: UIViewRepresentable {
+    let text: NSAttributedString
+
+    func makeUIView(context: Context) -> FlowTextView {
+        let v = FlowTextView()
+        v.delegate = context.coordinator
+        let tap = UITapGestureRecognizer(target: context.coordinator, action: #selector(Coordinator.tapped(_:)))
+        tap.delegate = context.coordinator
+        v.addGestureRecognizer(tap)
+        return v
+    }
+
+    func updateUIView(_ v: FlowTextView, context: Context) {
+        context.coordinator.openURL = context.environment.openURL
+        v.onTap = context.environment.choiceTap
+        if v.storage.isEqual(to: text) {
+            return
+        }
+        let selected = v.selectedRange
+        v.storage.setAttributedString(text)
+        if NSMaxRange(selected) <= text.length {
+            v.selectedRange = selected
+        }
+    }
+
+    func sizeThatFits(_ proposal: ProposedViewSize, uiView v: FlowTextView, context: Context) -> CGSize? {
+        context.coordinator.size(text, proposal.width.flatMap { $0.isFinite ? $0 : nil })
+    }
+
+    func makeCoordinator() -> Coordinator {
+        Coordinator()
+    }
+
+    final class Coordinator: NSObject, UITextViewDelegate, UIGestureRecognizerDelegate {
+        var openURL: OpenURLAction?
+        private let measure = FlowMeasure()
+
+        func size(_ text: NSAttributedString, _ width: CGFloat?) -> CGSize {
+            measure.size(text, width)
+        }
+
+        @objc func tapped(_ g: UITapGestureRecognizer) {
+            guard let v = g.view as? FlowTextView, let onTap = v.onTap, v.selectedRange.length == 0, !v.link(at: g.location(in: v)) else {
+                return
+            }
+            onTap()
+        }
+
+        func gestureRecognizer(_ g: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith other: UIGestureRecognizer) -> Bool {
+            true
+        }
+
+        func textView(_ textView: UITextView, primaryActionFor textItem: UITextItem, defaultAction: UIAction) -> UIAction? {
+            guard case .link(let url) = textItem.content, let openURL else {
+                return defaultAction
+            }
+            return UIAction { _ in
+                openURL(url)
+            }
+        }
+    }
+}
+#endif
 
 struct InlineView: View {
     let inlines: [MDInline]
@@ -776,8 +914,8 @@ struct InlineView: View {
     }
 
     private func flowString(_ a: AttributedString) -> NSAttributedString {
-        let s = NSMutableAttributedString(attributedString: try! NSAttributedString(a, including: \.appKit))
-        flowColor(s, NSColor(ctx.color))
+        let s = NSMutableAttributedString(attributedString: nativeString(a))
+        flowColor(s, PlatformColor(ctx.color))
         let p = NSMutableParagraphStyle()
         p.lineSpacing = 3
         s.addAttribute(.paragraphStyle, value: p, range: NSRange(location: 0, length: s.length))