Einladungscodes: registration_mode open|invite|closed, Admin-API /api/invites, App mit Code-Feld und Code-Verwaltung; v0.3.2

android/app/build.gradle.kts

@@ -31,8 +31,8 @@ android {
         applicationId = "dev.byteclaw.client"
         minSdk = 26
         targetSdk = 35
-        versionCode = 4
-        versionName = "0.3.1"
+        versionCode = 5
+        versionName = "0.3.2"
     }
 
     signingConfigs {

android/app/src/main/java/dev/byteclaw/client/MainActivity.kt

@@ -69,7 +69,7 @@ class MainActivity : ComponentActivity() {
                     }
                     NavHost(nav, startDestination = if (loggedIn) "chat" else "login") {
                         composable("login") {
-                            LoginScreen(state, onAuthenticate = { u, n, p, r -> vm.authenticate(u, n, p, r) },
+                            LoginScreen(state, onAuthenticate = { u, n, p, r, i -> vm.authenticate(u, n, p, r, i) }, onCheckMode = vm::checkRegistrationMode,
                                 onAdminToken = { u, t -> vm.useAdminToken(u, t) })
                         }
                         composable("chat") {
@@ -93,7 +93,8 @@ class MainActivity : ComponentActivity() {
                             SettingsScreen(state, onSave = vm::saveSettings, onTest = { s, cb -> vm.testConnection(s, cb) }, onBack = {
                                 if (!nav.popBackStack()) nav.navigate("chat") { popUpTo("settings") { inclusive = true } }
                             }, onLoadProviders = { vm.loadProviders() }, onLoadModels = { vm.loadModels(it) },
-                                onSelectProvider = { p, m -> vm.selectProvider(p, m) }, onLogout = vm::logout)
+                                onSelectProvider = { p, m -> vm.selectProvider(p, m) }, onLogout = vm::logout,
+                                onLoadInvites = { vm.loadInvites() }, onCreateInvite = { n, h -> vm.createInvite(n, h) }, onRevokeInvite = { vm.revokeInvite(it) })
                         }
                     }
                 }

android/app/src/main/java/dev/byteclaw/client/data/ByteClawApi.kt

@@ -60,6 +60,18 @@ class ByteClawApi(private val settings: ServerSettings) {
     suspend fun messages(sessionId: String): List<Message> =
         json.decodeFromString(call(Request.Builder().url(url("/api/sessions/$sessionId/messages")).build()))
 
+    suspend fun invites(): List<Invite> =
+        json.decodeFromString(call(Request.Builder().url(url("/api/invites")).build()))
+
+    suspend fun createInvite(maxUses: Int, expiresInHours: Int): Invite {
+        val body = json.encodeToString(InviteRequest.serializer(), InviteRequest(maxUses, expiresInHours)).toRequestBody(JSON)
+        return json.decodeFromString(call(Request.Builder().url(url("/api/invites")).post(body).build()))
+    }
+
+    suspend fun deleteInvite(code: String) {
+        call(Request.Builder().url(url("/api/invites/$code")).delete().build())
+    }
+
     suspend fun deleteSession(sessionId: String) {
         call(Request.Builder().url(url("/api/sessions/$sessionId")).delete().build())
     }
@@ -132,10 +144,11 @@ class ByteClawApi(private val settings: ServerSettings) {
         private val authJson = Json { ignoreUnknownKeys = true; explicitNulls = false }
 
         /** POST /api/auth/login or /register without a bearer token. Errors carry German text. */
-        suspend fun authenticate(serverUrl: String, username: String, password: String, register: Boolean): AuthResponse =
+        suspend fun authenticate(serverUrl: String, username: String, password: String, register: Boolean, inviteCode: String = ""): AuthResponse =
             withContext(Dispatchers.IO) {
                 val path = if (register) "/api/auth/register" else "/api/auth/login"
-                val body = authJson.encodeToString(Credentials.serializer(), Credentials(username.trim(), password)).toRequestBody(JSON)
+                val creds = Credentials(username.trim(), password, inviteCode.trim().uppercase().takeIf { register && it.isNotBlank() })
+                val body = authJson.encodeToString(Credentials.serializer(), creds).toRequestBody(JSON)
                 val req = Request.Builder().url((serverUrl.trim().trimEnd('/') + path).toHttpUrl()).post(body).build()
                 shared.newCall(req).execute().use { r ->
                     val text = r.body?.string().orEmpty()
@@ -144,6 +157,18 @@ class ByteClawApi(private val settings: ServerSettings) {
                 }
             }
 
+        /** Registration mode of a server; older servers without the endpoint count as "open". */
+        suspend fun registrationMode(serverUrl: String): String = withContext(Dispatchers.IO) {
+            runCatching {
+                val req = Request.Builder().url((serverUrl.trim().trimEnd('/') + "/api/auth/config").toHttpUrl()).build()
+                shared.newCall(req).execute().use { r ->
+                    if (r.code == 404) "open"
+                    else if (!r.isSuccessful) null
+                    else authJson.decodeFromString(AuthConfig.serializer(), r.body?.string().orEmpty()).registrationMode
+                }
+            }.getOrNull() ?: "unknown"
+        }
+
         private val JSON = "application/json".toMediaType()
         private val shared = OkHttpClient.Builder()
             .connectTimeout(15, TimeUnit.SECONDS)

android/app/src/main/java/dev/byteclaw/client/data/Models.kt

@@ -94,7 +94,29 @@ object ProviderPresets {
 data class RenameRequest(val title: String)
 
 @Serializable
-data class Credentials(val username: String, val password: String)
+data class Credentials(
+    val username: String,
+    val password: String,
+    @SerialName("invite_code") val inviteCode: String? = null,
+)
+
+/** GET /api/auth/config (public): "open", "invite" or "closed". */
+@Serializable
+data class AuthConfig(@SerialName("registration_mode") val registrationMode: String = "open")
+
+/** Invite code (admin only). */
+@Serializable
+data class Invite(
+    val code: String = "",
+    @SerialName("max_uses") val maxUses: Int = 1,
+    val uses: Int = 0,
+    @SerialName("expires_at") val expiresAt: String? = null,
+    @SerialName("created_at") val createdAt: String = "",
+    @SerialName("used_by") val usedBy: List<String> = emptyList(),
+)
+
+@Serializable
+data class InviteRequest(@SerialName("max_uses") val maxUses: Int = 1, @SerialName("expires_in_hours") val expiresInHours: Int = 0)
 
 @Serializable
 data class AuthUser(val id: Long = 0, val username: String = "", val admin: Boolean = false)
@@ -107,6 +129,10 @@ object AuthErrors {
     fun german(code: Int, body: String): String = when {
         code == 401 -> "Benutzername oder Passwort falsch"
         code == 409 -> "Benutzername ist bereits vergeben"
+        code == 400 && body.contains("invite code required") -> "Einladungscode erforderlich"
+        code == 403 && body.contains("invalid invite") -> "Einladungscode ist ungültig"
+        code == 403 && body.contains("already used") -> "Einladungscode wurde bereits verwendet"
+        code == 403 && body.contains("expired") -> "Einladungscode ist abgelaufen"
         code == 403 -> "Registrierung ist auf diesem Server deaktiviert"
         code == 429 -> "Zu viele Versuche – bitte später erneut probieren"
         code == 400 && body.contains("username") -> "Benutzername: 3–32 Zeichen (Buchstaben, Ziffern, . _ -)"

android/app/src/main/java/dev/byteclaw/client/ui/ChatViewModel.kt

@@ -4,6 +4,7 @@ import android.app.Application
 import androidx.lifecycle.AndroidViewModel
 import androidx.lifecycle.viewModelScope
 import dev.byteclaw.client.data.ActiveProvider
+import dev.byteclaw.client.data.Invite
 import dev.byteclaw.client.data.ByteClawApi
 import dev.byteclaw.client.data.AuthErrors
 import dev.byteclaw.client.data.UnauthorizedException
@@ -46,6 +47,11 @@ data class UiState(
     val authError: String? = null,
     /** From /api/auth/me: only the admin may change providers. */
     val isAdmin: Boolean = false,
+    /** Registration mode of the server entered on the login screen: open, invite, closed or unknown. */
+    val registrationMode: String = "unknown",
+    /** Admin: invite codes and status of the last invite action. */
+    val invites: List<Invite> = emptyList(),
+    val inviteStatus: String? = null,
 ) {
     /** What the current chat effectively uses: session override, else the global active provider. */
     val effectiveProvider: ActiveProvider? get() = sessionProvider ?: provider.active
@@ -81,13 +87,40 @@ class ChatViewModel(app: Application) : AndroidViewModel(app) {
     }
 
     /** Login or registration; on success the token is stored encrypted and the chat opens. */
-    fun authenticate(serverUrl: String, username: String, password: String, register: Boolean) {
+    fun checkRegistrationMode(serverUrl: String) {
+        if (ByteClawApi.validateUrl(serverUrl) != null) return
+        viewModelScope.launch {
+            val m = ByteClawApi.registrationMode(serverUrl)
+            _state.update { it.copy(registrationMode = m) }
+        }
+    }
+
+    fun loadInvites() = viewModelScope.launch {
+        runCatching { api().invites() }
+            .onSuccess { l -> _state.update { it.copy(invites = l) } }
+            .onFailure { e -> _state.update { it.copy(inviteStatus = "Codes laden fehlgeschlagen: ${e.message}") } }
+    }
+
+    fun createInvite(maxUses: Int, expiresInHours: Int) = viewModelScope.launch {
+        runCatching { api().createInvite(maxUses, expiresInHours) }
+            .onSuccess { i -> _state.update { it.copy(inviteStatus = "Neuer Code: ${i.code}") }; loadInvites() }
+            .onFailure { e -> _state.update { it.copy(inviteStatus = "Fehler: ${e.message}") } }
+    }
+
+    fun revokeInvite(code: String) = viewModelScope.launch {
+        runCatching { api().deleteInvite(code) }
+            .onSuccess { _state.update { it.copy(inviteStatus = "Code $code widerrufen") }; loadInvites() }
+            .onFailure { e -> _state.update { it.copy(inviteStatus = "Fehler: ${e.message}") } }
+    }
+
+    fun authenticate(serverUrl: String, username: String, password: String, register: Boolean, inviteCode: String = "") {
         val urlErr = ByteClawApi.validateUrl(serverUrl)
         val err = urlErr ?: AuthErrors.validate(username, password)
+            ?: if (register && _state.value.registrationMode == "invite" && inviteCode.isBlank()) "Einladungscode erforderlich" else null
         if (err != null) { _state.update { it.copy(authError = err) }; return }
         _state.update { it.copy(authBusy = true, authError = null) }
         viewModelScope.launch {
-            runCatching { ByteClawApi.authenticate(serverUrl, username, password, register) }
+            runCatching { ByteClawApi.authenticate(serverUrl, username, password, register, inviteCode) }
                 .onSuccess { r ->
                     store.save(ServerSettings(serverUrl, r.token, r.user.username))
                     _state.update { UiState(settings = store.load()) }

android/app/src/main/java/dev/byteclaw/client/ui/InviteSection.kt

@@ -0,0 +1,86 @@
+package dev.byteclaw.client.ui
+
+import android.content.Intent
+import androidx.compose.foundation.layout.*
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.ContentCopy
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material.icons.filled.Share
+import androidx.compose.material3.*
+import androidx.compose.runtime.*
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalClipboardManager
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.AnnotatedString
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.unit.dp
+import dev.byteclaw.client.data.Invite
+
+private val expiryOptions = listOf(0 to "Nie", 24 to "1 Tag", 24 * 7 to "7 Tage", 24 * 30 to "30 Tage")
+
+/** Admin only: create, copy/share, list and revoke invite codes. */
+@Composable
+fun InviteSection(
+    state: UiState,
+    onLoad: () -> Unit,
+    onCreate: (maxUses: Int, expiresInHours: Int) -> Unit,
+    onRevoke: (String) -> Unit,
+) {
+    LaunchedEffect(Unit) { onLoad() }
+    var maxUses by remember { mutableStateOf("1") }
+    var expiry by remember { mutableIntStateOf(0) }
+    var confirm by remember { mutableStateOf<String?>(null) }
+    val clip = LocalClipboardManager.current
+    val ctx = LocalContext.current
+    fun share(code: String) {
+        val text = "Einladung zu ByteClaw: ${state.settings.serverUrl}\nEinladungscode: $code"
+        val send = Intent(Intent.ACTION_SEND).setType("text/plain").putExtra(Intent.EXTRA_TEXT, text)
+        runCatching { ctx.startActivity(Intent.createChooser(send, null)) }
+    }
+    Card(Modifier.fillMaxWidth()) {
+        Column(Modifier.padding(16.dp), verticalArrangement = Arrangement.spacedBy(8.dp)) {
+            Row(verticalAlignment = Alignment.CenterVertically) {
+                Text("Einladungscodes", style = MaterialTheme.typography.titleMedium, modifier = Modifier.weight(1f))
+                TextButton(onClick = onLoad) { Text("Aktualisieren") }
+            }
+            Row(verticalAlignment = Alignment.CenterVertically, horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+                OutlinedTextField(maxUses, { v -> maxUses = v.filter { it.isDigit() }.take(4) }, Modifier.width(110.dp),
+                    label = { Text("Nutzungen") }, singleLine = true)
+                var open by remember { mutableStateOf(false) }
+                Box {
+                    OutlinedButton(onClick = { open = true }) { Text("Gültig: " + expiryOptions.first { it.first == expiry }.second) }
+                    DropdownMenu(open, { open = false }) {
+                        expiryOptions.forEach { (h, l) -> DropdownMenuItem(text = { Text(l) }, onClick = { expiry = h; open = false }) }
+                    }
+                }
+            }
+            Button(onClick = { onCreate((maxUses.toIntOrNull() ?: 1).coerceIn(1, 1000), expiry) }) { Text("Code erstellen") }
+            state.inviteStatus?.let { Text(it, style = MaterialTheme.typography.bodySmall) }
+            if (state.invites.isEmpty()) Text("Noch keine Codes.", style = MaterialTheme.typography.bodySmall)
+            state.invites.forEach { inv -> InviteRow(inv, onCopy = { clip.setText(AnnotatedString(inv.code)) }, onShare = { share(inv.code) }, onRevoke = { confirm = inv.code }) }
+        }
+    }
+    confirm?.let { code ->
+        AlertDialog(onDismissRequest = { confirm = null }, title = { Text("Code widerrufen?") },
+            text = { Text("$code kann danach nicht mehr verwendet werden. Bereits registrierte Konten bleiben bestehen.") },
+            confirmButton = { TextButton(onClick = { onRevoke(code); confirm = null }) { Text("Widerrufen") } },
+            dismissButton = { TextButton(onClick = { confirm = null }) { Text("Abbrechen") } })
+    }
+}
+
+@Composable
+private fun InviteRow(inv: Invite, onCopy: () -> Unit, onShare: () -> Unit, onRevoke: () -> Unit) {
+    val usedUp = inv.uses >= inv.maxUses
+    Row(verticalAlignment = Alignment.CenterVertically) {
+        Column(Modifier.weight(1f)) {
+            Text(inv.code, fontFamily = FontFamily.Monospace, color = if (usedUp) MaterialTheme.colorScheme.outline else MaterialTheme.colorScheme.onSurface)
+            val exp = inv.expiresAt?.take(10)?.let { " · bis $it" } ?: ""
+            val by = if (inv.usedBy.isNotEmpty()) " · " + inv.usedBy.joinToString() else ""
+            Text("${inv.uses}/${inv.maxUses} genutzt$exp$by", style = MaterialTheme.typography.bodySmall, color = MaterialTheme.colorScheme.outline)
+        }
+        IconButton(onClick = onCopy) { Icon(Icons.Filled.ContentCopy, "Kopieren") }
+        IconButton(onClick = onShare, enabled = !usedUp) { Icon(Icons.Filled.Share, "Teilen") }
+        IconButton(onClick = onRevoke) { Icon(Icons.Filled.Delete, "Widerrufen") }
+    }
+}

android/app/src/main/java/dev/byteclaw/client/ui/LoginScreen.kt

@@ -18,7 +18,8 @@ import dev.byteclaw.client.data.ByteClawApi
 @Composable
 fun LoginScreen(
     state: UiState,
-    onAuthenticate: (url: String, user: String, pass: String, register: Boolean) -> Unit,
+    onAuthenticate: (url: String, user: String, pass: String, register: Boolean, invite: String) -> Unit,
+    onCheckMode: (url: String) -> Unit = {},
     onAdminToken: (url: String, token: String) -> Unit = { _, _ -> },
     initialRegister: Boolean = false,
     initialUser: String? = null,
@@ -30,6 +31,9 @@ fun LoginScreen(
     var pass2 by remember { mutableStateOf("") }
     var adminMode by remember { mutableStateOf(false) }
     var token by remember { mutableStateOf("") }
+    var invite by remember { mutableStateOf("") }
+    LaunchedEffect(url, register) { if (register) { kotlinx.coroutines.delay(400); onCheckMode(url) } }
+    val needInvite = register && state.registrationMode == "invite"
     val urlError = if (url.isBlank()) null else ByteClawApi.validateUrl(url)
     val mismatch = register && pass2.isNotEmpty() && pass != pass2
 
@@ -65,14 +69,22 @@ fun LoginScreen(
                     OutlinedTextField(pass2, { pass2 = it }, Modifier.fillMaxWidth(), label = { Text("Passwort wiederholen") }, singleLine = true,
                         isError = mismatch, supportingText = if (mismatch) { { Text("Passwörter stimmen nicht überein") } } else null,
                         visualTransformation = PasswordVisualTransformation(), keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password))
+                    if (state.registrationMode == "closed") {
+                        Text("Registrierung ist auf diesem Server deaktiviert.", color = MaterialTheme.colorScheme.error)
+                    }
+                    if (needInvite) {
+                        OutlinedTextField(invite, { invite = it.uppercase() }, Modifier.fillMaxWidth(), label = { Text("Einladungscode") },
+                            placeholder = { Text("BC-XXXX-XXXX") }, singleLine = true,
+                            supportingText = { Text("Diesen Server kann man nur mit Einladung nutzen – frag den Admin nach einem Code.") })
+                    }
                 }
             }
             state.authError?.let { Text(it, color = MaterialTheme.colorScheme.error) }
             Button(
                 modifier = Modifier.fillMaxWidth(),
                 enabled = !state.authBusy && url.isNotBlank() && urlError == null &&
-                    (if (adminMode) token.isNotBlank() else user.isNotBlank() && pass.isNotEmpty() && (!register || pass == pass2)),
-                onClick = { if (adminMode) onAdminToken(url, token) else onAuthenticate(url, user, pass, register) },
+                    (if (adminMode) token.isNotBlank() else user.isNotBlank() && pass.isNotEmpty() && (!register || pass == pass2 && (!needInvite || invite.isNotBlank()))),
+                onClick = { if (adminMode) onAdminToken(url, token) else onAuthenticate(url, user, pass, register, invite) },
             ) {
                 if (state.authBusy) CircularProgressIndicator(Modifier.size(18.dp), strokeWidth = 2.dp)
                 else Text(when { adminMode -> "Mit Token verbinden"; register -> "Konto erstellen"; else -> "Anmelden" })

android/app/src/main/java/dev/byteclaw/client/ui/Screens.kt

@@ -271,6 +271,9 @@ fun SettingsScreen(
     onSelectProvider: (String, String) -> Unit = { _, _ -> },
     initialStatus: String? = null,
     onLogout: () -> Unit = {},
+    onLoadInvites: () -> Unit = {},
+    onCreateInvite: (Int, Int) -> Unit = { _, _ -> },
+    onRevokeInvite: (String) -> Unit = {},
 ) {
     var status by remember { mutableStateOf(initialStatus) }
     LaunchedEffect(state.settings) { if (state.settings.isConfigured) onLoadProviders() }
@@ -298,6 +301,7 @@ fun SettingsScreen(
             if (state.settings.isConfigured) {
                 if (state.isAdmin) {
                     item { ProviderSection(state.provider, onLoadProviders, onLoadModels, onSelectProvider) }
+                    item { InviteSection(state, onLoadInvites, onCreateInvite, onRevokeInvite) }
                 } else {
                     item {
                         Text("LLM-Provider: " + (state.provider.active?.let { ProviderPresets.label(it.provider) + " · " + it.model } ?: "–") +

android/app/src/test/java/dev/byteclaw/client/preview/PreviewScreenshots.kt

@@ -11,6 +11,7 @@ import dev.byteclaw.client.ui.ChatScreen
 import dev.byteclaw.client.ui.SessionsScreen
 import dev.byteclaw.client.ui.SettingsScreen
 import dev.byteclaw.client.ui.LoginScreen
+import dev.byteclaw.client.ui.InviteSection
 import dev.byteclaw.client.ui.UiState
 import dev.byteclaw.client.ui.ProviderUi
 import dev.byteclaw.client.data.ProviderInfo
@@ -152,13 +153,25 @@ class PreviewScreenshots(private val dark: Boolean) {
     }
 
     @Test fun login() = snap("login") {
-        LoginScreen(state = UiState(isAdmin = true, settings = ServerSettings("https://demo.byteclaw.example", "", "crypto")), onAuthenticate = { _, _, _, _ -> })
+        LoginScreen(state = UiState(isAdmin = true, settings = ServerSettings("https://demo.byteclaw.example", "", "crypto")), onAuthenticate = { _, _, _, _, _ -> })
     }
 
     @Test fun loginRegister() = snap("login_register") {
         LoginScreen(
-            state = UiState(isAdmin = true, settings = ServerSettings("https://demo.byteclaw.example"), authError = "Benutzername ist bereits vergeben"),
-            onAuthenticate = { _, _, _, _ -> }, initialRegister = true, initialUser = "crypto",
+            state = UiState(isAdmin = true, settings = ServerSettings("https://demo.byteclaw.example"), registrationMode = "invite", authError = "Einladungscode wurde bereits verwendet"),
+            onAuthenticate = { _, _, _, _, _ -> }, initialRegister = true, initialUser = "crypto",
+        )
+    }
+
+    @Test fun invites() = snap("invites") {
+        InviteSection(
+            state = UiState(isAdmin = true, settings = ServerSettings("https://byteclaw.jodabreit-ai.de", "t", "admin"), inviteStatus = "Neuer Code: BC-7KQM-X4TP",
+                invites = listOf(
+                    dev.byteclaw.client.data.Invite("BC-7KQM-X4TP", 1, 0, null, "2026-11-01T05:00:00Z"),
+                    dev.byteclaw.client.data.Invite("BC-H9RW-2NFD", 5, 2, "2026-11-08T05:00:00Z", "2026-11-01T04:00:00Z", listOf("anna", "ben")),
+                    dev.byteclaw.client.data.Invite("BC-3VXE-8MZA", 1, 1, null, "2026-10-31T20:00:00Z", listOf("crypto")),
+                )),
+            onLoad = {}, onCreate = { _, _ -> }, onRevoke = {},
         )
     }
 }