Validate Google Meet links on Join before opening browser

Require standard xxx-yyyy-zzz meeting codes. Accept full https URL, meet.google.com/… without scheme, or bare code; normalize to https://meet.google.com/{code}. Reject empty or invalid input with a clear alert. Update join field placeholder.

Made-with: Cursor

meetings_app/ViewController.swift

@@ -190,17 +190,11 @@ private extension ViewController {
     @objc private func joinMeetClicked(_ sender: Any?) {
         let rawInput = meetLinkField?.stringValue.trimmingCharacters(in: .whitespacesAndNewlines) ?? ""
 
-        if rawInput.isEmpty {
-            guard let url = URL(string: "https://meet.google.com/") else { return }
-            openInAppBrowser(with: url, policy: inAppBrowserDefaultPolicy)
-            return
-        }
-
-        let normalized = normalizedURLString(from: rawInput)
-        guard let url = URL(string: normalized),
-              let host = url.host?.lowercased(),
-              host.contains("meet.google.com") else {
-            showSimpleAlert(title: "Invalid Link", message: "Please enter a valid Google Meet link.")
+        guard let url = normalizedMeetJoinURL(from: rawInput) else {
+            showSimpleAlert(
+                title: "Invalid Meet link",
+                message: "Enter a valid Google Meet link or meeting code (for example nkd-grps-duv, meet.google.com/nkd-grps-duv, or https://meet.google.com/nkd-grps-duv)."
+            )
             return
         }
 
@@ -247,6 +241,49 @@ private extension ViewController {
         return "https://\(value)"
     }
 
+    /// Typical Meet meeting code shape: three hyphen-separated groups (e.g. `nkd-grps-duv`).
+    private func isValidMeetMeetingCode(_ code: String) -> Bool {
+        let trimmed = code.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard trimmed.isEmpty == false else { return false }
+        let pattern = "^[a-z0-9]{3}-[a-z0-9]{4}-[a-z0-9]{3}$"
+        return trimmed.range(of: pattern, options: [.regularExpression, .caseInsensitive]) != nil
+    }
+
+    /// Accepts `https://meet.google.com/...`, `meet.google.com/...`, or a bare code; returns canonical Meet URL or `nil`.
+    private func normalizedMeetJoinURL(from rawInput: String) -> URL? {
+        let trimmed = rawInput.trimmingCharacters(in: .whitespacesAndNewlines)
+        guard trimmed.isEmpty == false else { return nil }
+
+        let lower = trimmed.lowercased()
+
+        if lower.hasPrefix("http://") || lower.hasPrefix("https://") {
+            guard let url = URL(string: trimmed),
+                  let host = url.host?.lowercased(),
+                  host == "meet.google.com" || host.hasSuffix(".meet.google.com") else {
+                return nil
+            }
+            let path = url.path.trimmingCharacters(in: CharacterSet(charactersIn: "/"))
+            guard path.isEmpty == false else { return nil }
+            let firstSegment = path.split(separator: "/").first.map(String.init) ?? path
+            guard isValidMeetMeetingCode(firstSegment) else { return nil }
+            return URL(string: "https://meet.google.com/\(firstSegment.lowercased())")
+        }
+
+        if lower.hasPrefix("meet.google.com/") {
+            let afterHost = trimmed.dropFirst("meet.google.com/".count)
+            let beforeQuery = String(afterHost).split(separator: "?").first.map(String.init) ?? String(afterHost)
+            let firstSegment = beforeQuery.split(separator: "/").first.map(String.init) ?? beforeQuery
+            guard isValidMeetMeetingCode(firstSegment) else { return nil }
+            return URL(string: "https://meet.google.com/\(firstSegment.lowercased())")
+        }
+
+        if isValidMeetMeetingCode(trimmed) {
+            return URL(string: "https://meet.google.com/\(trimmed.lowercased())")
+        }
+
+        return nil
+    }
+
     private func openInAppBrowser(with url: URL, policy: InAppBrowserURLPolicy = .allowAll) {
         let browserController: InAppBrowserWindowController
         if let existing = inAppBrowserWindowController {
@@ -887,7 +924,7 @@ private extension ViewController {
         codeField.focusRingType = .none
         codeField.font = NSFont.systemFont(ofSize: 36 / 2, weight: .regular)
         codeField.textColor = palette.textPrimary
-        codeField.placeholderString = "Enter Link"
+        codeField.placeholderString = "Code or meet.google.com/…"
         codeInputShell.addSubview(codeField)
         meetLinkField = codeField
         codeCard.addSubview(codeTitle)