fixed erros with new user.mdoel

src/main/kotlin/com/oliver/kidio/backend/data/tables/ScreentimeTable.kt

@@ -0,0 +1,10 @@
+package com.oliver.kidio.backend.data.tables
+
+import org.jetbrains.exposed.sql.Table
+
+object ScreentimeTable : Table("user_screentime") {
+    val userId = varchar("user_id", 50)
+    val remainingSeconds = integer("remaining_seconds")
+
+    override val primaryKey = PrimaryKey(userId)
+}

src/main/kotlin/com/oliver/kidio/backend/data/tables/TasksTable.kt

@@ -0,0 +1,44 @@
+package com.oliver.kidio.backend.data.tables
+
+import org.jetbrains.exposed.sql.Table
+
+/*
+ * ERSETZT die bisherige TasksTable.kt komplett.
+ *
+ * Weg: options (Komma-String), correctAnswer (ein String)
+ * Hin: prompt_json, content_json, solution_json (je ein JSON-Text, siehe TaskModels.kt)
+ *
+ * WICHTIG - Migration: Diese Änderung ist nicht abwärtskompatibel zu vorhandenen Zeilen,
+ * die noch die alten Spalten "options"/"correct_answer" nutzen. Zwei Optionen:
+ *
+ * 1. (Empfohlen für Dev-Datenbanken ohne echte Nutzerdaten) Tabelle leeren und per
+ *    ./gradlew runIngestion neu befüllen lassen, siehe H5PIngestionCli.kt.
+ *
+ * 2. (Falls du bestehende Zeilen behalten willst) Vor dem Deploy ein einmaliges
+ *    Migrationsskript schreiben, das pro Zeile aus options+correctAnswer ein
+ *    MultipleChoiceContent/ChoiceSolution baut und in die neuen Spalten schreibt.
+ *    Sag Bescheid, dann schreibe ich dir das als eigenen Schritt.
+ */
+object TasksTable : Table("tasks") {
+    val id = varchar("id", 64)
+    val externalSource = varchar("external_source", 32).default("local")
+    val sourceUrl = text("source_url").nullable()
+    val license = varchar("license", 100).default("CC BY-SA 4.0")
+    val subject = varchar("subject", 64).default("Mathematik")
+    val minAge = integer("min_age").default(6)
+    val maxAge = integer("max_age").default(12)
+    val taskType = varchar("task_type", 32).default("MULTIPLE_CHOICE")
+
+    // NEU: ersetzen "question", "options", "correctAnswer"
+    val promptJson = text("prompt_json")
+    val contentJson = text("content_json")
+    val solutionJson = text("solution_json")
+
+    val rewardMinutes = integer("reward_minutes").default(5)
+
+    override val primaryKey = PrimaryKey(id)
+
+    init {
+        index("idx_tasks_filter", false, subject, minAge, maxAge)
+    }
+}

src/main/kotlin/com/oliver/kidio/backend/data/tables/UserTable.kt

@@ -0,0 +1,14 @@
+package com.oliver.kidio.backend.data.tables
+
+import org.jetbrains.exposed.sql.Table
+
+object UserTable : Table("users") {
+    val id = varchar("id", 36)
+    val email = varchar("email", 255).uniqueIndex()
+    val passwordHash = varchar("password_hash", 255)
+    val familyName = varchar("family_name", 100).default("Familie")
+    val childAge = integer("child_age").default(8)
+    val parentPin = varchar("parent_pin", 4).default("1234")
+
+    override val primaryKey = PrimaryKey(id)
+}

src/main/kotlin/com/oliver/kidio/backend/domain/models/Models.kt

@@ -1,21 +1,162 @@
-package com.oliver.kidio.backend
+package com.oliver.kidio.backend.domain.models
 
+import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
 
-// Eine Lernaufgabe (z. B. Mathe)
+/*
+ * ERSETZT die bisherige TaskModels.kt komplett.
+ *
+ * Warum: Task/ImportedTask hatten "options: List<String>" + "correctAnswer: String".
+ * Das kann nur "eine richtige Antwort aus einer Liste" abbilden (Multiple Choice,
+ * Wahr/Falsch). Lückentexte, Reihenfolgen oder Paare passen strukturell nicht rein.
+ *
+ * Neues Prinzip: Jede Aufgabe hat einen TYP (sealed interface TaskContent).
+ * Die Lösung (TaskSolution) ist ein eigenes, getrenntes Objekt und geht NIE an den Client.
+ *
+ * ACHTUNG (Kompilierfehler erwartet): Nach diesem Schritt melden ExposedKidioRepository.kt,
+ * TasksTable.kt und TaskRoutes.kt Fehler, weil sie noch die alten Klassen Task/ImportedTask/
+ * TaskVerifyRequest referenzieren. Das ist normal - die fixen wir in Schritt 2 bis 4.
+ */
+
+// ---------------------------------------------------------------- Bausteine
+
+@Serializable
+data class Media(
+    val emoji: String? = null,
+    val imageUrl: String? = null,
+    val audioUrl: String? = null,
+    val alt: String? = null,
+    // repeat = 3 mit emoji "🍎" zeigt drei Äpfel, praktisch zum Zählen für Kleinkinder
+    val repeat: Int = 1,
+)
+
+@Serializable
+data class Choice(
+    val id: String,
+    val label: String? = null,
+    val media: Media? = null,
+)
+
+@Serializable
+data class Prompt(
+    val text: String,
+    val media: Media? = null,
+    // Die App liest den Text per Text-to-Speech vor (wichtig für Kinder, die noch nicht lesen)
+    val speakAloud: Boolean = false,
+)
+
+// ---------------------------------------------------------------- Inhalt (geht an die App)
+
+@Serializable
+sealed interface TaskContent
+
+/** Ein oder mehrere richtige Antworten. Auch für Bild-Antworten (Kleinkinder). */
+@Serializable
+@SerialName("MULTIPLE_CHOICE")
+data class MultipleChoiceContent(
+    val choices: List<Choice>,
+    val multiSelect: Boolean = false,
+) : TaskContent
+
+/** Zwei große Knöpfe. Antwort-IDs sind immer "true" und "false". */
+@Serializable
+@SerialName("TRUE_FALSE")
+object TrueFalseContent : TaskContent {
+    const val TRUE_ID = "true"
+    const val FALSE_ID = "false"
+}
+
+/** Lückentext. Im Template stehen {1}, {2}, ... für die Lücken. */
+@Serializable
+@SerialName("FILL_BLANKS")
+data class FillBlanksContent(
+    val template: String,
+    val blanks: Int,
+    val wordBank: List<String> = emptyList(),
+) : TaskContent
+
+/** Elemente in die richtige Reihenfolge bringen. Kommt gemischt an. */
+@Serializable
+@SerialName("SORT")
+data class SortContent(
+    val items: List<Choice>,
+) : TaskContent
+
+/** Paare verbinden (links zu rechts). */
+@Serializable
+@SerialName("MATCH_PAIRS")
+data class MatchPairsContent(
+    val left: List<Choice>,
+    val right: List<Choice>,
+) : TaskContent
+
+/** Die richtigen Wörter im Text markieren. */
+@Serializable
+@SerialName("MARK_WORDS")
+data class MarkWordsContent(
+    val tokens: List<Choice>,
+) : TaskContent
+
+// ---------------------------------------------------------------- Lösung (bleibt auf dem Server)
+
+@Serializable
+sealed interface TaskSolution
+
+@Serializable
+@SerialName("CHOICE")
+data class ChoiceSolution(val correctIds: Set<String>) : TaskSolution
+
+/** Pro Lücke eine Liste akzeptierter Schreibweisen. */
+@Serializable
+@SerialName("FILL")
+data class FillSolution(val accepted: List<List<String>>) : TaskSolution
+
+@Serializable
+@SerialName("ORDER")
+data class OrderSolution(val orderedIds: List<String>) : TaskSolution
+
+@Serializable
+@SerialName("PAIRS")
+data class PairsSolution(val pairs: Map<String, String>) : TaskSolution
+
+// ---------------------------------------------------------------- Antwort des Kindes
+
+@Serializable
+sealed interface TaskAnswer
+
+@Serializable
+@SerialName("CHOICE")
+data class ChoiceAnswer(val selectedIds: Set<String>) : TaskAnswer
+
+@Serializable
+@SerialName("FILL")
+data class FillAnswer(val values: List<String>) : TaskAnswer
+
+@Serializable
+@SerialName("ORDER")
+data class OrderAnswer(val orderedIds: List<String>) : TaskAnswer
+
+@Serializable
+@SerialName("PAIRS")
+data class PairsAnswer(val pairs: Map<String, String>) : TaskAnswer
+
+// ---------------------------------------------------------------- API-Objekte
+
+/** Ersetzt die alte "Task"-Klasse. Geht an die App, ohne Lösung. */
 @Serializable
 data class Task(
     val id: String,
     val subject: String = "Mathematik",
     val minAge: Int = 6,
     val maxAge: Int = 12,
-    val question: String,
-    val options: List<String>,
+    val prompt: Prompt,
+    val content: TaskContent,
     val rewardMinutes: Int,
     val license: String? = null,
+    val sourceUrl: String? = null,
 )
 
-// Interne Datenklasse für importierte Aufgaben (Ingestion)
+/** Ersetzt die alte "ImportedTask"-Klasse. Interne Datenklasse für den Import. */
 data class ImportedTask(
     val id: String,
     val externalSource: String = "zum.de",
@@ -24,21 +165,20 @@ data class ImportedTask(
     val subject: String,
     val minAge: Int,
     val maxAge: Int,
-    val taskType: String = "MULTIPLE_CHOICE",
-    val question: String,
-    val options: List<String>,
-    val correctAnswer: String,
+    val prompt: Prompt,
+    val content: TaskContent,
+    val solution: TaskSolution,
     val rewardMinutes: Int = 5,
 )
 
-// Anfrage des Kindes, wenn es eine Aufgabe löst
+/** Ersetzt die alte "TaskVerifyRequest": statt eines Strings jetzt eine typisierte Antwort. */
 @Serializable
 data class TaskVerifyRequest(
     val taskId: String,
-    val selectedAnswer: String,
+    val answer: TaskAnswer,
 )
 
-// Antwort vom Server nach der Aufgaben-Prüfung
+/** Unverändert gegenüber vorher. */
 @Serializable
 data class TaskVerifyResponse(
     val isCorrect: Boolean,
@@ -46,50 +186,32 @@ data class TaskVerifyResponse(
     val message: String,
 )
 
-// Datenabgleich für die Bildschirmzeit (Sync)
-@Serializable
-data class SyncRequest(
-    val userId: String,
-    val usedSecondsSinceLastSync: Int,
-)
+// ---------------------------------------------------------------- Prüfung
 
-@Serializable
-data class SyncResponse(
-    val remainingSeconds: Int,
-    val isBlocked: Boolean,
-)
+object TaskChecker {
+    fun isCorrect(
+        solution: TaskSolution,
+        answer: TaskAnswer,
+    ): Boolean =
+        when {
+            solution is ChoiceSolution && answer is ChoiceAnswer ->
+                solution.correctIds == answer.selectedIds
 
-// --- NEU: AUTHENTIFIZIERUNG ---
+            solution is FillSolution && answer is FillAnswer ->
+                solution.accepted.size == answer.values.size &&
+                        solution.accepted.indices.all { i ->
+                            solution.accepted[i].any { normalize(it) == normalize(answer.values[i]) }
+                        }
 
-@Serializable
-data class RegisterRequest(
-    val email: String,
-    val passwordPlain: String,
-    val familyName: String,
-    val childAge: Int,
-    val parentPin: String,
-)
+            solution is OrderSolution && answer is OrderAnswer ->
+                solution.orderedIds == answer.orderedIds
 
-@Serializable
-data class LoginRequest(
-    val email: String,
-    val passwordPlain: String,
-)
+            solution is PairsSolution && answer is PairsAnswer ->
+                solution.pairs == answer.pairs
 
-@Serializable
-data class AuthResponse(
-    val token: String,
-    val userId: String,
-    val familyName: String,
-    val childAge: Int,
-)
+            // Typ von Antwort und Lösung passen nicht zusammen: immer falsch, nie einen Fehler werfen
+            else -> false
+        }
 
-// Interne Backend-Klasse (Domain Model).
-data class User(
-    val id: String,
-    val email: String,
-    val passwordHash: String,
-    val familyName: String,
-    val childAge: Int,
-    val parentPin: String,
-)
+    private fun normalize(s: String): String = s.trim().lowercase().replace(Regex("\\s+"), " ")
+}

src/main/kotlin/com/oliver/kidio/backend/domain/models/TaskJson.kt

@@ -0,0 +1,23 @@
+package com.oliver.kidio.backend.domain.models
+
+import kotlinx.serialization.json.Json
+
+/*
+ * NEUE DATEI (noch nicht vorhanden in deinem Projekt).
+ * Ablage: src/main/kotlin/com/oliver/kidio/backend/domain/models/TaskJson.kt
+ *
+ * Eine gemeinsame Json-Konfiguration, die überall dort verwendet wird, wo TaskContent,
+ * TaskSolution oder TaskAnswer serialisiert/deserialisiert werden: beim Schreiben/Lesen
+ * der DB-Spalten (content_json, solution_json, prompt_json) und im H5P-Mapper.
+ *
+ * classDiscriminator = "type" sorgt dafür, dass im JSON ein Feld "type" steht
+ * (z. B. "type": "MULTIPLE_CHOICE"), damit die App weiß, welche Variante sie bekommt.
+ */
+object TaskJson {
+    val json: Json =
+        Json {
+            classDiscriminator = "type"
+            ignoreUnknownKeys = true
+            encodeDefaults = true
+        }
+}

src/main/kotlin/com/oliver/kidio/backend/domain/models/User.kt

@@ -0,0 +1,13 @@
+package com.oliver.kidio.backend.domain.models
+
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class User(
+    val id: String,
+    val email: String,
+    val passwordHash: String,
+    val familyName: String,
+    val childAge: Int,
+    val parentPin: String
+)

src/main/kotlin/com/oliver/kidio/backend/domain/repository/ExposedKidioRepository.kt

@@ -0,0 +1,292 @@
+package com.oliver.kidio.backend.domain.repository
+
+import com.oliver.kidio.backend.data.database.DatabaseFactory
+import com.oliver.kidio.backend.data.database.RedisFactory
+import com.oliver.kidio.backend.data.tables.ScreentimeTable
+import com.oliver.kidio.backend.data.tables.TasksTable
+import com.oliver.kidio.backend.data.tables.UserTable
+import com.oliver.kidio.backend.domain.models.FillBlanksContent
+import com.oliver.kidio.backend.domain.models.ImportedTask
+import com.oliver.kidio.backend.domain.models.MarkWordsContent
+import com.oliver.kidio.backend.domain.models.MatchPairsContent
+import com.oliver.kidio.backend.domain.models.MultipleChoiceContent
+import com.oliver.kidio.backend.domain.models.Prompt
+import com.oliver.kidio.backend.domain.models.SortContent
+import com.oliver.kidio.backend.domain.models.Task
+import com.oliver.kidio.backend.domain.models.TaskContent
+import com.oliver.kidio.backend.domain.models.TaskJson
+import com.oliver.kidio.backend.domain.models.TaskSolution
+import com.oliver.kidio.backend.domain.models.TrueFalseContent
+import com.oliver.kidio.backend.domain.models.User
+import kotlinx.serialization.decodeFromString
+import kotlinx.serialization.encodeToString
+import org.jetbrains.exposed.sql.*
+import org.mindrot.jbcrypt.BCrypt
+import kotlin.collections.singleOrNull
+
+/*
+ * ERSETZT die bisherige ExposedKidioRepository.kt.
+ * Geändert: getTasks, upsertTask, getTaskAnswerAndReward (JSON-Spalten statt options/correctAnswer).
+ * Unverändert: getUserById, registerUser, getScreentime, updateScreentime, findByEmail,
+ * findById, verifyPassword, getExistingTaskIds.
+ */
+class ExposedKidioRepository : KidioRepository {
+    override suspend fun getTasks(
+        subject: String?,
+        age: Int?,
+        limit: Int,
+    ): List<Task> =
+        DatabaseFactory.dbQuery {
+            var query = TasksTable.selectAll()
+            if (!subject.isNullOrBlank()) {
+                query = query.where { TasksTable.subject.lowerCase() eq subject.trim().lowercase() }
+            }
+            if (age != null) {
+                query = query.andWhere { (TasksTable.minAge lessEq age) and (TasksTable.maxAge greaterEq age) }
+            }
+            val safeLimit = if (limit <= 0) 10 else limit
+            query.limit(safeLimit).mapNotNull { row -> rowToTaskOrNull(row) }
+        }
+
+    /** Baut eine Task aus einer DB-Zeile. Bei kaputtem JSON wird die Zeile übersprungen statt den Server abstürzen zu lassen. */
+    private fun rowToTaskOrNull(row: ResultRow): Task? =
+        try {
+            Task(
+                id = row[TasksTable.id],
+                subject = row[TasksTable.subject],
+                minAge = row[TasksTable.minAge],
+                maxAge = row[TasksTable.maxAge],
+                prompt = TaskJson.json.decodeFromString<Prompt>(row[TasksTable.promptJson]),
+                content = TaskJson.json.decodeFromString<TaskContent>(row[TasksTable.contentJson]),
+                rewardMinutes = row[TasksTable.rewardMinutes],
+                license = row[TasksTable.license],
+                sourceUrl = row[TasksTable.sourceUrl],
+            )
+        } catch (e: Exception) {
+            println("WARNUNG: Task ${row[TasksTable.id]} konnte nicht gelesen werden (kaputtes JSON?): ${e.message}")
+            null
+        }
+
+    override suspend fun getUserById(userId: String): User? =
+        DatabaseFactory.dbQuery {
+            UserTable.selectAll()
+                .where { UserTable.id eq userId }
+                .map {
+                    User(
+                        id = it[UserTable.id],
+                        email = it[UserTable.email],
+                        passwordHash = it[UserTable.passwordHash],
+                        familyName = it[UserTable.familyName],
+                        childAge = it[UserTable.childAge],
+                        parentPin = it[UserTable.parentPin],
+                    )
+                }
+                .singleOrNull()
+        }
+
+    override suspend fun getAllTasks(): List<Task> = getTasks(limit = 100)
+
+    override suspend fun getExistingTaskIds(externalSource: String): Set<String> =
+        DatabaseFactory.dbQuery {
+            TasksTable
+                .select(TasksTable.id)
+                .where { TasksTable.externalSource eq externalSource }
+                .map { it[TasksTable.id] }
+                .toSet()
+        }
+
+    override suspend fun upsertTask(task: ImportedTask): Boolean =
+        DatabaseFactory.dbQuery {
+            try {
+                val promptJson = TaskJson.json.encodeToString(task.prompt)
+                val contentJson = TaskJson.json.encodeToString(task.content)
+                val solutionJson = TaskJson.json.encodeToString(task.solution)
+
+                val updated =
+                    TasksTable.update({ TasksTable.id eq task.id }) {
+                        it[externalSource] = task.externalSource
+                        it[sourceUrl] = task.sourceUrl
+                        it[license] = task.license
+                        it[subject] = task.subject
+                        it[minAge] = task.minAge
+                        it[maxAge] = task.maxAge
+                        it[taskType] = task.content.typeName()
+                        it[TasksTable.promptJson] = promptJson
+                        it[TasksTable.contentJson] = contentJson
+                        it[TasksTable.solutionJson] = solutionJson
+                        it[rewardMinutes] = task.rewardMinutes
+                    }
+                if (updated == 0) {
+                    TasksTable.insert {
+                        it[id] = task.id
+                        it[externalSource] = task.externalSource
+                        it[sourceUrl] = task.sourceUrl
+                        it[license] = task.license
+                        it[subject] = task.subject
+                        it[minAge] = task.minAge
+                        it[maxAge] = task.maxAge
+                        it[taskType] = task.content.typeName()
+                        it[TasksTable.promptJson] = promptJson
+                        it[TasksTable.contentJson] = contentJson
+                        it[TasksTable.solutionJson] = solutionJson
+                        it[rewardMinutes] = task.rewardMinutes
+                    }
+                }
+                true
+            } catch (e: Exception) {
+                println("FEHLER beim Upsert von Task ${task.id}: ${e.message}")
+                false
+            }
+        }
+
+    override suspend fun registerUser(user: User): Boolean =
+        DatabaseFactory.dbQuery {
+            try {
+                UserTable.insert {
+                    it[id] = user.id
+                    it[email] = user.email
+                    it[passwordHash] = user.passwordHash
+                    it[familyName] = user.familyName
+                    it[childAge] = user.childAge
+                    it[parentPin] = user.parentPin
+                }
+                ScreentimeTable.insert {
+                    it[userId] = user.id
+                    it[remainingSeconds] = 1800 // Startguthaben: 30 Minuten
+                }
+                true
+            } catch (e: Exception) {
+                println("FEHLER bei Registrierung: ${e.message}")
+                false
+            }
+        }
+
+    override suspend fun getTaskAnswerAndReward(taskId: String): Pair<TaskSolution, Int>? =
+        DatabaseFactory.dbQuery {
+            TasksTable.selectAll()
+                .where { TasksTable.id eq taskId }
+                .map {
+                    val solution = TaskJson.json.decodeFromString<TaskSolution>(it[TasksTable.solutionJson])
+                    solution to it[TasksTable.rewardMinutes]
+                }
+                .singleOrNull()
+        }
+
+    override suspend fun getScreentime(userId: String): Int {
+        val redisKey = "screentime:$userId"
+
+        try {
+            RedisFactory.getResource().use { jedis ->
+                val cachedSeconds = jedis.get(redisKey)
+                if (cachedSeconds != null) {
+                    println("DEBUG: Bildschirmzeit für $userId aus REDIS geladen: $cachedSeconds Sek")
+                    return cachedSeconds.toInt()
+                }
+            }
+        } catch (e: Exception) {
+            println("WARNUNG: Konnte nicht aus Redis lesen (Postgres-Fallback genutzt): ${e.message}")
+        }
+
+        val dbSeconds =
+            DatabaseFactory.dbQuery {
+                ScreentimeTable.selectAll()
+                    .where { ScreentimeTable.userId eq userId }
+                    .map { it[ScreentimeTable.remainingSeconds] }
+                    .singleOrNull() ?: 1800
+            }
+
+        try {
+            RedisFactory.getResource().use { jedis ->
+                jedis.setex(redisKey, 3600, dbSeconds.toString())
+                println("DEBUG: Bildschirmzeit für $userId in REDIS gecacht.")
+            }
+        } catch (e: Exception) {
+            println("WARNUNG: Konnte Wert nicht in Redis speichern: ${e.message}")
+        }
+        return dbSeconds
+    }
+
+    override suspend fun updateScreentime(
+        userId: String,
+        seconds: Int,
+    ) {
+        DatabaseFactory.dbQuery {
+            val rowsUpdated =
+                ScreentimeTable.update({ ScreentimeTable.userId eq userId }) {
+                    it[remainingSeconds] = seconds
+                }
+            if (rowsUpdated == 0) {
+                ScreentimeTable.insert {
+                    it[ScreentimeTable.userId] = userId
+                    it[ScreentimeTable.remainingSeconds] = seconds
+                }
+            }
+        }
+        val redisKey = "screentime:$userId"
+        try {
+            RedisFactory.getResource().use { jedis ->
+                jedis.setex(redisKey, 3600, seconds.toString())
+                println("DEBUG: Bildschirmzeit für $userId in REDIS aktualisiert auf $seconds Sek")
+            }
+        } catch (e: Exception) {
+            println("WARNUNG: Konnte Redis nicht aktualisieren: ${e.message}")
+        }
+    }
+
+    override suspend fun findByEmail(email: String): User? =
+        DatabaseFactory.dbQuery {
+            UserTable.selectAll()
+                .where { UserTable.email eq email }
+                .map {
+                    User(
+                        id = it[UserTable.id],
+                        email = it[UserTable.email],
+                        passwordHash = it[UserTable.passwordHash],
+                        familyName = it[UserTable.familyName],
+                        childAge = it[UserTable.childAge],
+                        parentPin = it[UserTable.parentPin],
+                    )
+                }
+                .singleOrNull()
+        }
+
+    override suspend fun findById(userId: String): User? =
+        DatabaseFactory.dbQuery {
+            UserTable.selectAll()
+                .where { UserTable.id eq userId }
+                .map {
+                    User(
+                        id = it[UserTable.id],
+                        email = it[UserTable.email],
+                        passwordHash = it[UserTable.passwordHash],
+                        familyName = it[UserTable.familyName],
+                        childAge = it[UserTable.childAge],
+                        parentPin = it[UserTable.parentPin],
+                    )
+                }
+                .singleOrNull()
+        }
+
+    override suspend fun verifyPassword(
+        password: String,
+        passwordHash: String,
+    ): Boolean {
+        return BCrypt.checkpw(password, passwordHash)
+    }
+}
+
+/**
+ * Liefert den Aufgabentyp als String für die taskType-Spalte (nur zum Filtern/Debuggen
+ * in der DB, nicht Teil der eigentlichen Prüf-Logik - die läuft über TaskChecker).
+ * Bewusst als explizites "when" statt Reflection, damit der Compiler bei einer neuen
+ * TaskContent-Variante hier einen Fehler wirft ("not exhaustive"), falls sie vergessen wird.
+ */
+private fun TaskContent.typeName(): String =
+    when (this) {
+        is MultipleChoiceContent -> "MULTIPLE_CHOICE"
+        is TrueFalseContent -> "TRUE_FALSE"
+        is FillBlanksContent -> "FILL_BLANKS"
+        is SortContent -> "SORT"
+        is MatchPairsContent -> "MATCH_PAIRS"
+        is MarkWordsContent -> "MARK_WORDS"
+    }

src/main/kotlin/com/oliver/kidio/backend/domain/repository/InMemoryKidioRepository.kt

@@ -0,0 +1,101 @@
+package com.oliver.kidio.backend.domain.repository
+
+import com.oliver.kidio.backend.domain.models.ImportedTask
+import com.oliver.kidio.backend.domain.models.Task
+import com.oliver.kidio.backend.domain.models.TaskSolution
+import com.oliver.kidio.backend.domain.models.User
+import org.mindrot.jbcrypt.BCrypt
+
+/*
+ * ERSETZT die bisherige InMemoryKidioRepository.kt.
+ * Wird u.a. in Tests genutzt (ServerTest o.ä.) - Signatur muss zum neuen KidioRepository-
+ * Interface passen, sonst kompiliert das Test-Modul nicht mehr.
+ */
+class InMemoryKidioRepository : KidioRepository {
+    private val tasks = mutableListOf<ImportedTask>()
+
+    private val screentimes =
+        mutableMapOf(
+            "default_user" to 1800,
+        )
+    private val users = mutableListOf<User>()
+
+    override suspend fun getAllTasks(): List<Task> = getTasks(limit = 100)
+
+    override suspend fun getTasks(
+        subject: String?,
+        age: Int?,
+        limit: Int,
+    ): List<Task> {
+        val safeLimit = if (limit <= 0) 10 else limit
+        return tasks.filter { task ->
+            val matchSubject = subject.isNullOrBlank() || task.subject.equals(subject.trim(), ignoreCase = true)
+            val matchAge = age == null || (task.minAge <= age && task.maxAge >= age)
+            matchSubject && matchAge
+        }.take(safeLimit).map {
+            Task(
+                id = it.id,
+                subject = it.subject,
+                minAge = it.minAge,
+                maxAge = it.maxAge,
+                prompt = it.prompt,
+                content = it.content,
+                rewardMinutes = it.rewardMinutes,
+                license = it.license,
+                sourceUrl = it.sourceUrl,
+            )
+        }
+    }
+
+    override suspend fun getUserById(userId: String): User? {
+        return users.find { it.id == userId }
+    }
+
+    override suspend fun getExistingTaskIds(externalSource: String): Set<String> {
+        return tasks
+            .filter { it.externalSource == externalSource }
+            .map { it.id }
+            .toSet()
+    }
+
+    override suspend fun upsertTask(task: ImportedTask): Boolean {
+        tasks.removeIf { it.id == task.id }
+        tasks.add(task)
+        return true
+    }
+
+    override suspend fun getTaskAnswerAndReward(taskId: String): Pair<TaskSolution, Int>? {
+        val task = tasks.find { it.id == taskId } ?: return null
+        return task.solution to task.rewardMinutes
+    }
+
+    override suspend fun getScreentime(userId: String): Int = screentimes[userId] ?: 1800
+
+    override suspend fun updateScreentime(
+        userId: String,
+        seconds: Int,
+    ) {
+        screentimes[userId] = seconds
+    }
+
+    override suspend fun findByEmail(email: String): User? {
+        return users.find { it.email == email }
+    }
+
+    override suspend fun findById(userId: String): User? {
+        return users.find { it.id == userId }
+    }
+
+    override suspend fun verifyPassword(
+        password: String,
+        passwordHash: String,
+    ): Boolean {
+        return BCrypt.checkpw(password, passwordHash)
+    }
+
+    override suspend fun registerUser(user: User): Boolean {
+        users.add(user)
+        screentimes[user.id] = 1800
+        return true
+    }
+}

src/main/kotlin/com/oliver/kidio/backend/domain/repository/KidioRepository.kt

@@ -1,379 +1,21 @@
 package com.oliver.kidio.backend.domain.repository
 
-import com.oliver.kidio.backend.ImportedTask
-import com.oliver.kidio.backend.Task
-import com.oliver.kidio.backend.User
-import com.oliver.kidio.backend.data.database.DatabaseFactory
-import com.oliver.kidio.backend.data.database.RedisFactory
-import com.oliver.kidio.backend.data.database.ScreentimeTable
-import com.oliver.kidio.backend.data.database.TasksTable
-import com.oliver.kidio.backend.data.database.UserTable
-import org.jetbrains.exposed.sql.*
-import org.jetbrains.exposed.sql.SqlExpressionBuilder.eq
-import org.jetbrains.exposed.sql.SqlExpressionBuilder.greaterEq
-import org.jetbrains.exposed.sql.SqlExpressionBuilder.lessEq
-import org.jetbrains.exposed.sql.lowerCase
-import org.mindrot.jbcrypt.BCrypt
+import com.oliver.kidio.backend.domain.models.ImportedTask
+import com.oliver.kidio.backend.domain.models.Task
+import com.oliver.kidio.backend.domain.models.TaskSolution
+import com.oliver.kidio.backend.domain.models.User
 
 interface KidioRepository {
     suspend fun getAllTasks(): List<Task> = getTasks(limit = 100)
-
     suspend fun getUserById(userId: String): User?
-
-    suspend fun getTasks(
-        subject: String? = null,
-        age: Int? = null,
-        limit: Int = 10,
-    ): List<Task>
-
-    // Mit suspend markiert, damit es zur DatabaseFactory.dbQuery Architektur passt
+    suspend fun findById(userId: String): User?
+    suspend fun getTasks(subject: String? = null, age: Int? = null, limit: Int = 10): List<Task>
     suspend fun getExistingTaskIds(externalSource: String = "zum.de"): Set<String>
-
     suspend fun upsertTask(task: ImportedTask): Boolean
-
-    suspend fun getTaskAnswerAndReward(taskId: String): Pair<String, Int>?
-
+    suspend fun getTaskAnswerAndReward(taskId: String): Pair<TaskSolution, Int>?
     suspend fun getScreentime(userId: String): Int
-
-    suspend fun updateScreentime(
-        userId: String,
-        seconds: Int,
-    )
-
+    suspend fun updateScreentime(userId: String, seconds: Int)
     suspend fun findByEmail(email: String): User?
-
-    suspend fun verifyPassword(
-        password: String,
-        passwordHash: String,
-    ): Boolean
-
+    suspend fun verifyPassword(password: String, passwordHash: String): Boolean
     suspend fun registerUser(user: User): Boolean
-}
-
-class ExposedKidioRepository : KidioRepository {
-    override suspend fun getTasks(
-        subject: String?,
-        age: Int?,
-        limit: Int,
-    ): List<Task> =
-        DatabaseFactory.dbQuery {
-            var query = TasksTable.selectAll()
-            if (!subject.isNullOrBlank()) {
-                query = query.where { TasksTable.subject.lowerCase() eq subject.trim().lowercase() }
-            }
-            if (age != null) {
-                query = query.andWhere { (TasksTable.minAge lessEq age) and (TasksTable.maxAge greaterEq age) }
-            }
-            val safeLimit = if (limit <= 0) 10 else limit
-            query.limit(safeLimit).map {
-                Task(
-                    id = it[TasksTable.id],
-                    subject = it[TasksTable.subject],
-                    minAge = it[TasksTable.minAge],
-                    maxAge = it[TasksTable.maxAge],
-                    question = it[TasksTable.question],
-                    options = it[TasksTable.options].split(",").map { opt -> opt.trim() },
-                    rewardMinutes = it[TasksTable.rewardMinutes],
-                    license = it[TasksTable.license],
-                )
-            }
-        }
-
-    override suspend fun getUserById(userId: String): User? =
-        DatabaseFactory.dbQuery {
-            UserTable.selectAll()
-                .where { UserTable.id eq userId }
-                .map {
-                    User(
-                        id = it[UserTable.id],
-                        email = it[UserTable.email],
-                        passwordHash = it[UserTable.passwordHash],
-                        familyName = it[UserTable.familyName],
-                        childAge = it[UserTable.childAge],
-                        parentPin = it[UserTable.parentPin],
-                    )
-                }
-                .singleOrNull()
-        }
-
-    override suspend fun getAllTasks(): List<Task> = getTasks(limit = 100)
-
-    // NEU: Implementierung für Exposed (PostgreSQL)
-    override suspend fun getExistingTaskIds(externalSource: String): Set<String> =
-        DatabaseFactory.dbQuery {
-            TasksTable
-                .select(TasksTable.id) // Wir brauchen nur die ID-Spalte
-                .where { TasksTable.externalSource eq externalSource }
-                .map { it[TasksTable.id] }
-                .toSet()
-        }
-
-    override suspend fun upsertTask(task: ImportedTask): Boolean =
-        DatabaseFactory.dbQuery {
-            try {
-                val updated =
-                    TasksTable.update({ TasksTable.id eq task.id }) {
-                        it[externalSource] = task.externalSource
-                        it[sourceUrl] = task.sourceUrl
-                        it[license] = task.license
-                        it[subject] = task.subject
-                        it[minAge] = task.minAge
-                        it[maxAge] = task.maxAge
-                        it[taskType] = task.taskType
-                        it[question] = task.question
-                        it[options] = task.options.joinToString(",")
-                        it[correctAnswer] = task.correctAnswer
-                        it[rewardMinutes] = task.rewardMinutes
-                    }
-                if (updated == 0) {
-                    TasksTable.insert {
-                        it[id] = task.id
-                        it[externalSource] = task.externalSource
-                        it[sourceUrl] = task.sourceUrl
-                        it[license] = task.license
-                        it[subject] = task.subject
-                        it[minAge] = task.minAge
-                        it[maxAge] = task.maxAge
-                        it[taskType] = task.taskType
-                        it[question] = task.question
-                        it[options] = task.options.joinToString(",")
-                        it[correctAnswer] = task.correctAnswer
-                        it[rewardMinutes] = task.rewardMinutes
-                    }
-                }
-                true
-            } catch (e: Exception) {
-                println("FEHLER beim Upsert von Task ${task.id}: ${e.message}")
-                false
-            }
-        }
-
-    override suspend fun registerUser(user: User): Boolean =
-        DatabaseFactory.dbQuery {
-            try {
-                UserTable.insert {
-                    it[id] = user.id
-                    it[email] = user.email
-                    it[passwordHash] = user.passwordHash
-                    it[familyName] = user.familyName
-                    it[childAge] = user.childAge
-                    it[parentPin] = user.parentPin
-                }
-                ScreentimeTable.insert {
-                    it[userId] = user.id
-                    it[remainingSeconds] = 1800 // Startguthaben: 30 Minuten
-                }
-                true
-            } catch (e: Exception) {
-                println("FEHLER bei Registrierung: ${e.message}")
-                false
-            }
-        }
-
-    override suspend fun getTaskAnswerAndReward(taskId: String): Pair<String, Int>? =
-        DatabaseFactory.dbQuery {
-            TasksTable.selectAll()
-                .where { TasksTable.id eq taskId }
-                .map { it[TasksTable.correctAnswer] to it[TasksTable.rewardMinutes] }
-                .singleOrNull()
-        }
-
-    override suspend fun getScreentime(userId: String): Int {
-        val redisKey = "screentime:$userId"
-
-        try {
-            RedisFactory.getResource().use { jedis ->
-                val cachedSeconds = jedis.get(redisKey)
-                if (cachedSeconds != null) {
-                    println("DEBUG: Bildschirmzeit für $userId aus REDIS geladen: $cachedSeconds Sek")
-                    return cachedSeconds.toInt()
-                }
-            }
-        } catch (e: Exception) {
-            println("WARNUNG: Konnte nicht aus Redis lesen (Postgres-Fallback genutzt): ${e.message}")
-        }
-
-        val dbSeconds =
-            DatabaseFactory.dbQuery {
-                ScreentimeTable.selectAll()
-                    .where { ScreentimeTable.userId eq userId }
-                    .map { it[ScreentimeTable.remainingSeconds] }
-                    .singleOrNull() ?: 1800
-            }
-
-        try {
-            RedisFactory.getResource().use { jedis ->
-                jedis.setex(redisKey, 3600, dbSeconds.toString())
-                println("DEBUG: Bildschirmzeit für $userId in REDIS gecacht.")
-            }
-        } catch (e: Exception) {
-            println("WARNUNG: Konnte Wert nicht in Redis speichern: ${e.message}")
-        }
-        return dbSeconds
-    }
-
-    override suspend fun updateScreentime(
-        userId: String,
-        seconds: Int,
-    ) {
-        DatabaseFactory.dbQuery {
-            val rowsUpdated =
-                ScreentimeTable.update({ ScreentimeTable.userId eq userId }) {
-                    it[remainingSeconds] = seconds
-                }
-            if (rowsUpdated == 0) {
-                ScreentimeTable.insert {
-                    it[ScreentimeTable.userId] = userId
-                    it[ScreentimeTable.remainingSeconds] = seconds
-                }
-            }
-        }
-        val redisKey = "screentime:$userId"
-        try {
-            RedisFactory.getResource().use { jedis ->
-                jedis.setex(redisKey, 3600, seconds.toString())
-                println("DEBUG: Bildschirmzeit für $userId in REDIS aktualisiert auf $seconds Sek")
-            }
-        } catch (e: Exception) {
-            println("WARNUNG: Konnte Redis nicht aktualisieren: ${e.message}")
-        }
-    }
-
-    override suspend fun findByEmail(email: String): User? =
-        DatabaseFactory.dbQuery {
-            UserTable.selectAll()
-                .where { UserTable.email eq email }
-                .map {
-                    User(
-                        id = it[UserTable.id],
-                        email = it[UserTable.email],
-                        passwordHash = it[UserTable.passwordHash],
-                        familyName = it[UserTable.familyName],
-                        childAge = it[UserTable.childAge],
-                        parentPin = it[UserTable.parentPin],
-                    )
-                }
-                .singleOrNull()
-        }
-
-    override suspend fun verifyPassword(
-        password: String,
-        passwordHash: String,
-    ): Boolean {
-        return BCrypt.checkpw(password, passwordHash)
-    }
-}
-
-class InMemoryKidioRepository : KidioRepository {
-    private val tasks =
-        mutableListOf(
-            ImportedTask(
-                id = "t1",
-                externalSource = "manual",
-                subject = "Mathematik",
-                minAge = 6,
-                maxAge = 10,
-                taskType = "MULTIPLE_CHOICE",
-                question = "Was ist 12 + 15?",
-                options = listOf("25", "27", "30", "22"),
-                correctAnswer = "27",
-                rewardMinutes = 10,
-                license = "CC BY-SA 4.0",
-                sourceUrl = "local",
-            ),
-            ImportedTask(
-                id = "t2",
-                externalSource = "manual",
-                subject = "Mathematik",
-                minAge = 7,
-                maxAge = 12,
-                taskType = "MULTIPLE_CHOICE",
-                question = "Was ist 8 x 7?",
-                options = listOf("54", "56", "64", "48"),
-                correctAnswer = "56",
-                rewardMinutes = 15,
-                license = "CC BY-SA 4.0",
-                sourceUrl = "local",
-            ),
-        )
-    private val screentimes =
-        mutableMapOf(
-            "default_user" to 1800,
-        )
-    private val users = mutableListOf<User>()
-
-    override suspend fun getAllTasks(): List<Task> = getTasks(limit = 100)
-
-    override suspend fun getTasks(
-        subject: String?,
-        age: Int?,
-        limit: Int,
-    ): List<Task> {
-        val safeLimit = if (limit <= 0) 10 else limit
-        return tasks.filter { task ->
-            val matchSubject = subject.isNullOrBlank() || task.subject.equals(subject.trim(), ignoreCase = true)
-            val matchAge = age == null || (task.minAge <= age && task.maxAge >= age)
-            matchSubject && matchAge
-        }.take(safeLimit).map {
-            Task(
-                id = it.id,
-                subject = it.subject,
-                minAge = it.minAge,
-                maxAge = it.maxAge,
-                question = it.question,
-                options = it.options,
-                rewardMinutes = it.rewardMinutes,
-                license = it.license,
-            )
-        }
-    }
-
-    override suspend fun getUserById(userId: String): User? {
-        return users.find { it.id == userId }
-    }
-
-    // NEU: Implementierung für InMemory (Mock-Daten)
-    override suspend fun getExistingTaskIds(externalSource: String): Set<String> {
-        return tasks
-            .filter { it.externalSource == externalSource }
-            .map { it.id }
-            .toSet()
-    }
-
-    override suspend fun upsertTask(task: ImportedTask): Boolean {
-        tasks.removeIf { it.id == task.id }
-        tasks.add(task)
-        return true
-    }
-
-    override suspend fun getTaskAnswerAndReward(taskId: String): Pair<String, Int>? {
-        val task = tasks.find { it.id == taskId } ?: return null
-        return task.correctAnswer to task.rewardMinutes
-    }
-
-    override suspend fun getScreentime(userId: String): Int = screentimes[userId] ?: 1800
-
-    override suspend fun updateScreentime(
-        userId: String,
-        seconds: Int,
-    ) {
-        screentimes[userId] = seconds
-    }
-
-    override suspend fun findByEmail(email: String): User? {
-        return users.find { it.email == email }
-    }
-
-    override suspend fun verifyPassword(
-        password: String,
-        passwordHash: String,
-    ): Boolean {
-        return BCrypt.checkpw(password, passwordHash)
-    }
-
-    override suspend fun registerUser(user: User): Boolean {
-        users.add(user)
-        screentimes[user.id] = 1800
-        return true
-    }
-}
+}