composeApp/src/androidMain/kotlin/su/reya/coop/screens/ProfileScreen.kt

@@ -85,6 +85,8 @@ fun ProfileScreen(pubkey: String, screening: Boolean = false) {
 
     var addressVerified by remember { mutableStateOf(false) }
     var lastActivity by remember { mutableStateOf<Timestamp?>(null) }
+    var isContact by remember { mutableStateOf(false) }
+    var mutualContacts by remember { mutableStateOf<Set<PublicKey>>(emptySet()) }
 
     LaunchedEffect(screening) {
         if (screening) {
@@ -95,6 +97,10 @@ fun ProfileScreen(pubkey: String, screening: Boolean = false) {
                 }
                 // Get the last activity
                 viewModel.verifyActivity(pubkey)?.let { lastActivity = it }
+                // Check contact
+                viewModel.verifyContact(pubkey).let { isContact = it }
+                // Get mutual contacts
+                viewModel.mutualContacts(pubkey).let { mutualContacts = it }
             }
         }
     }

shared/src/commonMain/kotlin/su/reya/coop/Nostr.kt

@@ -296,7 +296,11 @@ class Nostr {
 
                             if (event.kind().asStd()?.equals(KindStandard.CONTACT_LIST) == true) {
                                 if (isSignedByUser(event = event)) {
-                                    onContactListUpdate(event.tags().publicKeys())
+                                    val pubkeys = event.tags().publicKeys();
+                                    // Get mutual contacts
+                                    getMutualContacts(pubkeys)
+                                    // Emit contact list update
+                                    onContactListUpdate(pubkeys)
                                 }
                             }
 
@@ -313,6 +317,7 @@ class Nostr {
                                 // Logic to notify UI after processing
                                 // Cancel previous tracker if it exists
                                 eoseTrackerJob?.cancel()
+
                                 // Start a new tracker
                                 eoseTrackerJob = launch {
                                     delay(10000.milliseconds) // Wait for 10 seconds
@@ -360,6 +365,27 @@ class Nostr {
         }
     }
 
+    private suspend fun getMutualContacts(pubkeys: List<PublicKey>) {
+        try {
+            val kind = Kind.fromStd(KindStandard.CONTACT_LIST);
+            val filter = Filter().kind(kind).authors(pubkeys).limit(200u)
+            val opts = SubscribeAutoCloseOptions().exitPolicy(ReqExitPolicy.ExitOnEose)
+
+            val target = mutableMapOf<RelayUrl, List<Filter>>()
+            NostrManager.BOOTSTRAP_RELAYS.forEach { relay ->
+                target[RelayUrl.parse(relay)] = listOf(filter)
+            }
+
+            client?.subscribe(
+                target = ReqTarget.manual(target),
+                id = "mutual-contacts",
+                closeOn = opts,
+            )
+        } catch (e: Exception) {
+            throw IllegalStateException("Failed to fetch mutual contacts: ${e.message}", e)
+        }
+    }
+
     private suspend fun getCachedRumor(giftId: EventId): UnsignedEvent? {
         try {
             val filter = Filter().identifier(giftId.toHex())
@@ -977,4 +1003,39 @@ class Nostr {
             throw IllegalStateException("Failed to get latest activity: ${e.message}", e)
         }
     }
+
+    suspend fun verifyContact(pubkey: PublicKey): Boolean {
+        try {
+            val kind = Kind.fromStd(KindStandard.CONTACT_LIST)
+            val filter = Filter().kind(kind).author(pubkey).limit(1u)
+
+            val events = client?.database()?.query(filter)
+            val pubkeys = events?.first()?.tags()?.publicKeys() ?: listOf()
+
+            return pubkeys.contains(pubkey)
+        } catch (e: Exception) {
+            throw IllegalStateException("Failed to get mutual contacts: ${e.message}", e)
+        }
+    }
+
+    suspend fun mutualContacts(pubkey: PublicKey): Set<PublicKey> {
+        try {
+            val currentUser =
+                signer.getPublicKeyAsync() ?: throw IllegalStateException("User not signed in")
+
+            val kind = Kind.fromStd(KindStandard.CONTACT_LIST)
+            val filter = Filter().kind(kind).pubkey(pubkey).limit(1u)
+
+            val events = client?.database()?.query(filter)
+            val contacts = mutableSetOf<PublicKey>()
+
+            events?.toVec()?.filter { it.author() != currentUser }?.forEach { event ->
+                contacts.add(event.author())
+            }
+
+            return contacts.toSet()
+        } catch (e: Exception) {
+            throw IllegalStateException("Failed to get mutual contacts: ${e.message}", e)
+        }
+    }
 }

shared/src/commonMain/kotlin/su/reya/coop/NostrViewModel.kt

@@ -839,6 +839,24 @@ class NostrViewModel(
             null
         }
     }
+
+    suspend fun verifyContact(pubkey: PublicKey): Boolean {
+        return try {
+            nostr.verifyContact(pubkey)
+        } catch (e: Exception) {
+            showError("Error: ${e.message}")
+            false
+        }
+    }
+
+    suspend fun mutualContacts(pubkey: PublicKey): Set<PublicKey> {
+        return try {
+            nostr.mutualContacts(pubkey)
+        } catch (e: Exception) {
+            showError("Error: ${e.message}")
+            setOf()
+        }
+    }
 }
 
 fun PublicKey.short(): String {