Feat/b links (#481)

* feat(cashu): auto-link cashu tokens in chat

- Detect cashuA/cashuB tokens via regex and render as tappable links
- Style like URLs (underline; blue for others, orange for self)
- Add openURL handler for cashu: scheme to delegate to wallet on iOS
- Respect existing heavy-content gating and long-message collapsing

* feat(ln): auto-link Lightning invoices and LNURL + lightning: scheme\n\n- Detect BOLT11 (lnbc/lntb/lnbcrt...), LNURL bech32, and lightning: URIs\n- Render as tappable links with lightning: scheme; consistent styling\n- Handle lightning: in openURL alongside cashu:

* feat(links): replace raw Cashu/Lightning tokens with compact chips (🥜 pay via cashu / ⚡ pay via lightning) while keeping them tappable

* style(links): add subtle background highlight to cashu/lightning chips

* ui(links): render Lightning/Cashu as rounded chips under message with padding; remove inline chip text

* ui(links): increase chip padding and corner radius; add extra top padding for chip row

* scroll: auto-scroll to bottom when sending a new message (public + private), regardless of current scroll position

* scroll(geo): when switching geohashes, scroll to top of chat (first visible message)

---------

Co-authored-by: jack <jackjackbits@users.noreply.github.com>

bitchat/ViewModels/ChatViewModel.swift

@@ -2785,19 +2785,33 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                     : .system(size: 14, design: .monospaced)
                 result.append(AttributedString(content).mergingAttributes(plainStyle))
             } else {
-                let hashtagPattern = "#([a-zA-Z0-9_]+)"
+            let hashtagPattern = "#([a-zA-Z0-9_]+)"
-                // Allow optional '#abcd' suffix in mentions
+            // Allow optional '#abcd' suffix in mentions
-                let mentionPattern = "@([\\p{L}0-9_]+(?:#[a-fA-F0-9]{4})?)"
+            let mentionPattern = "@([\\p{L}0-9_]+(?:#[a-fA-F0-9]{4})?)"
-                
+            // Cashu token detector: cashuA/cashuB + long base64url
-                let hashtagRegex = try? NSRegularExpression(pattern: hashtagPattern, options: [])
+            let cashuPattern = "\\bcashu[AB][A-Za-z0-9_-]{60,}\\b"
-                let mentionRegex = try? NSRegularExpression(pattern: mentionPattern, options: [])
+            // Lightning invoices and links
-                
+            let bolt11Pattern = "(?i)\\bln(bc|tb|bcrt)[0-9][a-z0-9]{50,}\\b"
-                // Use NSDataDetector for URL detection
+            let lnurlPattern = "(?i)\\blnurl1[a-z0-9]{20,}\\b"
-                let detector = try? NSDataDetector(types: NSTextCheckingResult.CheckingType.link.rawValue)
+            let lightningSchemePattern = "(?i)\\blightning:[^\\s]+"
+            
+            let hashtagRegex = try? NSRegularExpression(pattern: hashtagPattern, options: [])
+            let mentionRegex = try? NSRegularExpression(pattern: mentionPattern, options: [])
+            let cashuRegex = try? NSRegularExpression(pattern: cashuPattern, options: [])
+            let bolt11Regex = try? NSRegularExpression(pattern: bolt11Pattern, options: [])
+            let lnurlRegex = try? NSRegularExpression(pattern: lnurlPattern, options: [])
+            let lightningSchemeRegex = try? NSRegularExpression(pattern: lightningSchemePattern, options: [])
+            
+            // Use NSDataDetector for URL detection
+            let detector = try? NSDataDetector(types: NSTextCheckingResult.CheckingType.link.rawValue)
             
             let hashtagMatches = hashtagRegex?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
             let mentionMatches = mentionRegex?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
             let urlMatches = detector?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
+            let cashuMatches = cashuRegex?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
+            let lightningMatches = lightningSchemeRegex?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
+            let bolt11Matches = bolt11Regex?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
+            let lnurlMatches = lnurlRegex?.matches(in: content, options: [], range: NSRange(location: 0, length: content.count)) ?? []
             
             // Combine and sort matches, excluding hashtags/URLs overlapping mentions
             let mentionRanges = mentionMatches.map { $0.range(at: 0) }
@@ -2815,6 +2829,25 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
             for match in urlMatches where !overlapsMention(match.range) {
                 allMatches.append((match.range, "url"))
             }
+            for match in cashuMatches where !overlapsMention(match.range(at: 0)) {
+                allMatches.append((match.range(at: 0), "cashu"))
+            }
+            // Lightning scheme first to avoid overlapping submatches
+            for match in lightningMatches where !overlapsMention(match.range(at: 0)) {
+                allMatches.append((match.range(at: 0), "lightning"))
+            }
+            // Exclude overlaps with lightning/url for bolt11/lnurl
+            let occupied: [NSRange] = urlMatches.map { $0.range } + lightningMatches.map { $0.range(at: 0) }
+            func overlapsOccupied(_ r: NSRange) -> Bool {
+                for or in occupied { if NSIntersectionRange(r, or).length > 0 { return true } }
+                return false
+            }
+            for match in bolt11Matches where !overlapsMention(match.range(at: 0)) && !overlapsOccupied(match.range(at: 0)) {
+                allMatches.append((match.range(at: 0), "bolt11"))
+            }
+            for match in lnurlMatches where !overlapsMention(match.range(at: 0)) && !overlapsOccupied(match.range(at: 0)) {
+                allMatches.append((match.range(at: 0), "lnurl"))
+            }
             allMatches.sort { $0.range.location < $1.range.location }
             
             // Build content with styling
@@ -2884,6 +2917,23 @@ class ChatViewModel: ObservableObject, BitchatDelegate {
                                 : .system(size: 14, design: .monospaced)
                             tagStyle.foregroundColor = baseColor
                             result.append(AttributedString(matchText).mergingAttributes(tagStyle))
+                        } else if type == "cashu" {
+                            // Skip inline token; a styled chip is rendered below the message
+                            // We insert a single space to avoid words sticking together
+                            var spacer = AttributeContainer()
+                            spacer.foregroundColor = baseColor
+                            spacer.font = isSelf
+                                ? .system(size: 14, weight: .bold, design: .monospaced)
+                                : .system(size: 14, design: .monospaced)
+                            result.append(AttributedString(" ").mergingAttributes(spacer))
+                        } else if type == "lightning" || type == "bolt11" || type == "lnurl" {
+                            // Skip inline invoice/link; a styled chip is rendered below the message
+                            var spacer = AttributeContainer()
+                            spacer.foregroundColor = baseColor
+                            spacer.font = isSelf
+                                ? .system(size: 14, weight: .bold, design: .monospaced)
+                                : .system(size: 14, design: .monospaced)
+                            result.append(AttributedString(" ").mergingAttributes(spacer))
                         } else {
                             // Keep URL styling (blue + underline for non-self, orange for self)
                             var matchStyle = AttributeContainer()

bitchat/Views/ContentView.swift

@@ -357,6 +357,46 @@ struct ContentView: View {
                                                 .id("\(message.id)-\(urlInfo.url.absoluteString)")
                                         }
                                     }
+
+                                    // Render payment chips (Lightning / Cashu) with rounded background
+                                    let lightningLinks = message.content.extractLightningLinks()
+                                    let cashuTokens = message.content.extractCashuTokens()
+                                    if !lightningLinks.isEmpty || !cashuTokens.isEmpty {
+                                        HStack(spacing: 8) {
+                                            ForEach(Array(lightningLinks.prefix(3)).indices, id: \.self) { i in
+                                                let link = lightningLinks[i]
+                                                PaymentChipView(
+                                                    emoji: "⚡",
+                                                    label: "pay via lightning",
+                                                    colorScheme: colorScheme
+                                                ) {
+                                                    #if os(iOS)
+                                                    if let url = URL(string: link) { UIApplication.shared.open(url) }
+                                                    #else
+                                                    if let url = URL(string: link) { NSWorkspace.shared.open(url) }
+                                                    #endif
+                                                }
+                                            }
+                                            ForEach(Array(cashuTokens.prefix(3)).indices, id: \.self) { i in
+                                                let token = cashuTokens[i]
+                                                let enc = token.addingPercentEncoding(withAllowedCharacters: .alphanumerics.union(CharacterSet(charactersIn: "-_"))) ?? token
+                                                let urlStr = "cashu:\(enc)"
+                                                PaymentChipView(
+                                                    emoji: "🥜",
+                                                    label: "pay via cashu",
+                                                    colorScheme: colorScheme
+                                                ) {
+                                                    #if os(iOS)
+                                                    if let url = URL(string: urlStr) { UIApplication.shared.open(url) }
+                                                    #else
+                                                    if let url = URL(string: urlStr) { NSWorkspace.shared.open(url) }
+                                                    #endif
+                                                }
+                                            }
+                                        }
+                                        .padding(.top, 6)
+                                        .padding(.leading, 2)
+                                    }
                                 }
                             }
                         }
@@ -477,8 +517,16 @@ struct ContentView: View {
             }
             .onChange(of: viewModel.messages.count) { _ in
                 if privatePeer == nil && !viewModel.messages.isEmpty {
-                    // Only autoscroll when user is at/near bottom
+                    // If the newest message is from me, always scroll to bottom
-                    guard isAtBottom.wrappedValue else { return }
+                    let lastMsg = viewModel.messages.last!
+                    let isFromSelf = (lastMsg.sender == viewModel.nickname) || lastMsg.sender.hasPrefix(viewModel.nickname + "#")
+                    if !isFromSelf {
+                        // Only autoscroll when user is at/near bottom
+                        guard isAtBottom.wrappedValue else { return }
+                    } else {
+                        // Ensure we consider ourselves at bottom for subsequent messages
+                        isAtBottom.wrappedValue = true
+                    }
                     // Throttle scroll animations to prevent excessive UI updates
                     let now = Date()
                     if now.timeIntervalSince(lastScrollTime) > 0.5 {
@@ -525,8 +573,15 @@ struct ContentView: View {
                 if let peerID = privatePeer,
                    let messages = viewModel.privateChats[peerID],
                    !messages.isEmpty {
-                    // Only autoscroll when user is at/near bottom
+                    // If the newest private message is from me, always scroll
-                    guard isAtBottom.wrappedValue else { return }
+                    let lastMsg = messages.last!
+                    let isFromSelf = (lastMsg.sender == viewModel.nickname) || lastMsg.sender.hasPrefix(viewModel.nickname + "#")
+                    if !isFromSelf {
+                        // Only autoscroll when user is at/near bottom
+                        guard isAtBottom.wrappedValue else { return }
+                    } else {
+                        isAtBottom.wrappedValue = true
+                    }
                     // Same throttling for private chats
                     let now = Date()
                     if now.timeIntervalSince(lastScrollTime) > 0.5 {
@@ -549,6 +604,25 @@ struct ContentView: View {
                     }
                 }
             }
+            #if os(iOS)
+            .onChange(of: locationManager.selectedChannel) { newChannel in
+                // When switching to a new geohash channel, scroll to the top of that chat
+                guard privatePeer == nil else { return }
+                switch newChannel {
+                case .mesh:
+                    break
+                case .location(let ch):
+                    // Compute the top item (first of the current window)
+                    let contextKey = "geo:\(ch.geohash)"
+                    let top = viewModel.messages.suffix(100).first?.id
+                    let target = top.map { "\(contextKey)|\($0)" }
+                    isAtBottom.wrappedValue = false
+                    DispatchQueue.main.async {
+                        if let target = target { proxy.scrollTo(target, anchor: .top) }
+                    }
+                }
+            }
+            #endif
             .onAppear {
                 // Also check when view appears
                 if let peerID = privatePeer {
@@ -565,6 +639,19 @@ struct ContentView: View {
                 }
             }
         }
+        .environment(\.openURL, OpenURLAction { url in
+            // Intercept custom cashu: links created in attributed text
+            if let scheme = url.scheme?.lowercased(), scheme == "cashu" || scheme == "lightning" {
+                #if os(iOS)
+                UIApplication.shared.open(url)
+                return .handled
+                #else
+                // On non-iOS platforms, let the system handle or ignore
+                return .systemAction
+                #endif
+            }
+            return .systemAction
+        })
     }
     
     // MARK: - Input View
@@ -1257,6 +1344,44 @@ struct ContentView: View {
 
 // MARK: - Helper Views
 
+// Rounded payment chip button
+private struct PaymentChipView: View {
+    let emoji: String
+    let label: String
+    let colorScheme: ColorScheme
+    let action: () -> Void
+    
+    private var fgColor: Color {
+        colorScheme == .dark ? Color.green : Color(red: 0, green: 0.5, blue: 0)
+    }
+    private var bgColor: Color {
+        colorScheme == .dark ? Color.gray.opacity(0.18) : Color.gray.opacity(0.12)
+    }
+    private var border: Color { fgColor.opacity(0.25) }
+    
+    var body: some View {
+        Button(action: action) {
+            HStack(spacing: 6) {
+                Text(emoji)
+                Text(label)
+                    .font(.system(size: 12, weight: .semibold, design: .monospaced))
+            }
+            .padding(.vertical, 6)
+            .padding(.horizontal, 12)
+            .background(
+                RoundedRectangle(cornerRadius: 12)
+                    .fill(bgColor)
+            )
+            .overlay(
+                RoundedRectangle(cornerRadius: 12)
+                    .stroke(border, lineWidth: 1)
+            )
+            .foregroundColor(fgColor)
+        }
+        .buttonStyle(.plain)
+    }
+}
+
 // Helper view for rendering message content (plain, no hashtag/mention formatting)
 struct MessageContentView: View {
     let message: BitchatMessage

bitchat/Views/LinkPreviewView.swift

@@ -439,6 +439,55 @@ extension String {
         }
         return current >= threshold
     }
+
+    // Extract up to `max` Cashu tokens (cashuA/cashuB)
+    func extractCashuTokens(max: Int = 3) -> [String] {
+        let pattern = "\\bcashu[AB][A-Za-z0-9_-]{60,}\\b"
+        guard let regex = try? NSRegularExpression(pattern: pattern, options: []) else { return [] }
+        let ns = self as NSString
+        let range = NSRange(location: 0, length: ns.length)
+        var found: [String] = []
+        for m in regex.matches(in: self, options: [], range: range) {
+            if m.numberOfRanges > 0 {
+                let token = ns.substring(with: m.range(at: 0))
+                found.append(token)
+                if found.count >= max { break }
+            }
+        }
+        return found
+    }
+
+    // Extract Lightning payloads (scheme, BOLT11, LNURL). Returned as lightning:<payload>
+    func extractLightningLinks(max: Int = 3) -> [String] {
+        var results: [String] = []
+        let ns = self as NSString
+        let full = NSRange(location: 0, length: ns.length)
+        // lightning: scheme
+        if let schemeRx = try? NSRegularExpression(pattern: "(?i)\\blightning:[^\\s]+", options: []) {
+            for m in schemeRx.matches(in: self, options: [], range: full) {
+                let s = ns.substring(with: m.range(at: 0))
+                results.append(s)
+                if results.count >= max { return results }
+            }
+        }
+        // BOLT11
+        if let boltRx = try? NSRegularExpression(pattern: "(?i)\\bln(bc|tb|bcrt)[0-9][a-z0-9]{50,}\\b", options: []) {
+            for m in boltRx.matches(in: self, options: [], range: full) {
+                let s = ns.substring(with: m.range(at: 0))
+                results.append("lightning:\(s)")
+                if results.count >= max { return results }
+            }
+        }
+        // LNURL bech32
+        if let lnurlRx = try? NSRegularExpression(pattern: "(?i)\\blnurl1[a-z0-9]{20,}\\b", options: []) {
+            for m in lnurlRx.matches(in: self, options: [], range: full) {
+                let s = ns.substring(with: m.range(at: 0))
+                results.append("lightning:\(s)")
+                if results.count >= max { return results }
+            }
+        }
+        return results
+    }
 }
 
 #Preview {