feat: add AppDatabase and move payment caching to db

app/build.gradle.kts

@@ -1,6 +1,7 @@
 plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.compose)
+    alias(libs.plugins.ksp)
 }
 
 android {
@@ -70,7 +71,12 @@ dependencies {
     implementation(libs.androidx.lifecycle.viewmodel.ktx)
     implementation(libs.androidx.lifecycle.viewmodel.compose)
 
-    // Biometric
+    // Room
+    implementation(libs.room.runtime)
+    implementation(libs.room.ktx)
+    ksp(libs.room.compiler)
+
+    // Biometrics
     implementation(libs.androidx.biometric)
 
     // JSON

app/src/main/java/com/bitcointxoko/gudariwallet/data/PaymentCacheRepository.kt

@@ -1,59 +1,47 @@
 package com.bitcointxoko.gudariwallet.data
 
 import android.content.Context
-import android.content.SharedPreferences
 import android.util.Log
-import com.bitcointxoko.gudariwallet.api.GsonProvider
 import com.bitcointxoko.gudariwallet.api.PaymentDetailResponse
 import com.bitcointxoko.gudariwallet.api.PaymentRecord
+import com.bitcointxoko.gudariwallet.data.db.AppDatabase
+import com.bitcointxoko.gudariwallet.data.db.toDomain
+import com.bitcointxoko.gudariwallet.data.db.toEntity
 import com.bitcointxoko.gudariwallet.util.WalletConstants
-import com.bitcointxoko.gudariwallet.api.SuccessAction
-import com.bitcointxoko.gudariwallet.api.SuccessActionAdapter
-import com.google.gson.GsonBuilder
-import com.google.gson.reflect.TypeToken
 
 private const val TAG = "PaymentCacheRepository"
 
 class PaymentCacheRepository(context: Context) {
 
-    private val prefs: SharedPreferences = context.getSharedPreferences(
+    private val dao = AppDatabase.getInstance(context).paymentDao()
-        WalletConstants.PAYMENTS_PREFS_NAME, Context.MODE_PRIVATE
+
-    )
-    private val gson = GsonProvider.gson
     // ── In-memory detail cache — immutable once confirmed, no TTL needed ──────
     private val detailCache = mutableMapOf<String, PaymentDetailResponse>()
 
     // ── Payment list ──────────────────────────────────────────────────────────
 
     /** Load the persisted first-page list. Returns empty list if nothing cached or cache is stale. */
-    fun loadCachedPayments(): List<PaymentRecord> {
+    suspend fun loadCachedPayments(): List<PaymentRecord> {
-        val json      = prefs.getString(WalletConstants.PAYMENTS_PREFS_KEY, null) ?: return emptyList()
+        val savedAt = dao.getLatestSavedAt() ?: run {
-        val savedAt   = prefs.getLong(WalletConstants.PAYMENTS_PREFS_SAVED_AT, 0L)
+            Log.d(TAG, "PAYMENTS [CACHE MISS] no rows in db")
-        val ageMs     = System.currentTimeMillis() - savedAt
+            return emptyList()
-
+        }
+        val ageMs = System.currentTimeMillis() - savedAt
         if (ageMs > WalletConstants.PAYMENTS_CACHE_TTL_MS) {
             Log.d(TAG, "PAYMENTS [CACHE STALE] age ${ageMs / 1000}s — ignoring persisted list")
             return emptyList()
         }
-
+        return dao.getAll().map { it.toDomain() }.also {
-        return runCatching {
+            Log.d(TAG, "PAYMENTS [CACHE HIT ] loaded ${it.size} payments (age ${ageMs / 1000}s)")
-            val type: java.lang.reflect.Type = object : TypeToken<List<PaymentRecord>>() {}.type
-            val list: List<PaymentRecord> = gson.fromJson(json, type)
-            Log.d(TAG, "PAYMENTS [CACHE HIT ] loaded ${list.size} payments (age ${ageMs / 1000}s)")
-            list
-        }.getOrElse {
-            Log.w(TAG, "PAYMENTS [CACHE ERR ] failed to deserialise: ${it.message}")
-            emptyList()
         }
     }
 
-    /** Persist the first page of payments to SharedPreferences. */
+    /** Persist the first page of payments to the database. */
-    fun savePayments(payments: List<PaymentRecord>) {
+    suspend fun savePayments(payments: List<PaymentRecord>) {
+        val now = System.currentTimeMillis()
         runCatching {
-            prefs.edit()
+            dao.deleteAll()
-                .putString(WalletConstants.PAYMENTS_PREFS_KEY, gson.toJson(payments))
+            dao.insertAll(payments.map { it.toEntity(now) })
-                .putLong(WalletConstants.PAYMENTS_PREFS_SAVED_AT, System.currentTimeMillis())
-                .apply()
             Log.d(TAG, "PAYMENTS [PERSIST  ] saved ${payments.size} payments")
         }.onFailure {
             Log.w(TAG, "PAYMENTS [PERSIST  ] write failed: ${it.message}")
@@ -63,11 +51,10 @@ class PaymentCacheRepository(context: Context) {
     // ── Payment detail ────────────────────────────────────────────────────────
 
     /** Returns a cached detail response, or null if not yet fetched this session. */
-    fun getCachedDetail(checkingId: String): PaymentDetailResponse? {
+    fun getCachedDetail(checkingId: String): PaymentDetailResponse? =
-        return detailCache[checkingId]?.also {
+        detailCache[checkingId]?.also {
             Log.d(TAG, "PAYMENTS [DETAIL HIT] $checkingId")
         }
-    }
 
     /** Store a detail response in the in-memory cache. */
     fun saveDetail(checkingId: String, detail: PaymentDetailResponse) {
@@ -76,12 +63,9 @@ class PaymentCacheRepository(context: Context) {
     }
 
     /** Clear everything — useful for testing and logout. */
-    fun clearAll() {
+    suspend fun clearAll() {
         detailCache.clear()
-        prefs.edit()
+        dao.deleteAll()
-            .remove(WalletConstants.PAYMENTS_PREFS_KEY)
-            .remove(WalletConstants.PAYMENTS_PREFS_SAVED_AT)
-            .apply()
         Log.d(TAG, "PAYMENTS [CLEARED   ] cache wiped")
     }
 }

app/src/main/java/com/bitcointxoko/gudariwallet/data/db/AppDatabase.kt

@@ -0,0 +1,31 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import androidx.room.TypeConverters
+
+@Database(
+    entities = [PaymentRecordEntity::class],
+    version = 1,
+    exportSchema = false
+)
+@TypeConverters(PaymentConverters::class)
+abstract class AppDatabase : RoomDatabase() {
+
+    abstract fun paymentDao(): PaymentDao
+
+    companion object {
+        @Volatile private var INSTANCE: AppDatabase? = null
+
+        fun getInstance(context: Context): AppDatabase =
+            INSTANCE ?: synchronized(this) {
+                INSTANCE ?: Room.databaseBuilder(
+                    context.applicationContext,
+                    AppDatabase::class.java,
+                    "gudari_wallet.db"
+                ).build().also { INSTANCE = it }
+            }
+    }
+}

app/src/main/java/com/bitcointxoko/gudariwallet/data/db/PaymentConverters.kt

@@ -0,0 +1,19 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import androidx.room.TypeConverter
+import com.bitcointxoko.gudariwallet.api.PaymentExtra
+import com.bitcointxoko.gudariwallet.api.GsonProvider
+
+object PaymentConverters {
+    private val gson = GsonProvider.gson
+
+    @TypeConverter
+    @JvmStatic
+    fun fromExtra(extra: PaymentExtra?): String? =
+        extra?.let { gson.toJson(it) }
+
+    @TypeConverter
+    @JvmStatic
+    fun toExtra(json: String?): PaymentExtra? =
+        json?.let { gson.fromJson(it, PaymentExtra::class.java) }
+}

app/src/main/java/com/bitcointxoko/gudariwallet/data/db/PaymentDao.kt

@@ -0,0 +1,24 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+
+@Dao
+interface PaymentDao {
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertAll(payments: List<PaymentRecordEntity>)
+
+    /** Returns all rows ordered by time descending. */
+    @Query("SELECT * FROM payment_records ORDER BY time DESC")
+    suspend fun getAll(): List<PaymentRecordEntity>
+
+    /** Returns the savedAt timestamp of the most recently written row, or null if table is empty. */
+    @Query("SELECT savedAt FROM payment_records ORDER BY savedAt DESC LIMIT 1")
+    suspend fun getLatestSavedAt(): Long?
+
+    @Query("DELETE FROM payment_records")
+    suspend fun deleteAll()
+}

app/src/main/java/com/bitcointxoko/gudariwallet/data/db/PaymentRecordEntity.kt

@@ -0,0 +1,23 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+import androidx.room.TypeConverters
+
+@Entity(tableName = "payment_records")
+@TypeConverters(PaymentConverters::class)
+data class PaymentRecordEntity(
+    @PrimaryKey
+    val checkingId: String,
+    val paymentHash: String,
+    val amountMsat: Long,
+    val feeMsat: Long,
+    val memo: String?,
+    val time: String,
+    val status: String,
+    val bolt11: String?,
+    val pending: Boolean,
+    val preimage: String?,
+    val extra: String?,          // JSON blob — PaymentExtra serialised by TypeConverter
+    val savedAt: Long            // epoch ms — used for TTL check
+)

app/src/main/java/com/bitcointxoko/gudariwallet/data/db/PaymentRecordMapper.kt

@@ -0,0 +1,38 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import com.bitcointxoko.gudariwallet.api.PaymentRecord
+import com.bitcointxoko.gudariwallet.data.db.PaymentRecordEntity
+
+fun PaymentRecord.toEntity(savedAt: Long): PaymentRecordEntity =
+    PaymentRecordEntity(
+        checkingId  = checkingId,
+        paymentHash = paymentHash,
+        amountMsat  = amountMsat,
+        feeMsat     = feeMsat,
+        memo        = memo,
+        time        = time,
+        status      = status,
+        bolt11      = bolt11,
+        pending     = pending,
+        preimage    = preimage,
+        extra       = extra?.let { com.bitcointxoko.gudariwallet.api.GsonProvider.gson.toJson(it) },
+        savedAt     = savedAt
+    )
+
+fun PaymentRecordEntity.toDomain(): PaymentRecord =
+    PaymentRecord(
+        checkingId  = checkingId,
+        paymentHash = paymentHash,
+        amountMsat  = amountMsat,
+        feeMsat     = feeMsat,
+        memo        = memo,
+        time        = time,
+        status      = status,
+        bolt11      = bolt11,
+        pending     = pending,
+        preimage    = preimage,
+        extra       = extra?.let {
+            com.bitcointxoko.gudariwallet.api.GsonProvider.gson
+                .fromJson(it, com.bitcointxoko.gudariwallet.api.PaymentExtra::class.java)
+        }
+    )

app/src/main/java/com/bitcointxoko/gudariwallet/ui/HistoryViewModel.kt

@@ -35,9 +35,7 @@ class HistoryViewModel(
         // Cache read moved to IO dispatcher — never blocks the main thread,
         // so navigation to HistoryScreen is instant on tap.
         viewModelScope.launch {
-            val cached = withContext(Dispatchers.IO) {
+            val cached = paymentCache.loadCachedPayments()
-                paymentCache.loadCachedPayments()
-            }
             if (cached.isNotEmpty()) {
                 Log.d("HistoryViewModel", "PAYMENTS [INIT      ] Showing ${cached.size} cached payments immediately")
                 _state.value = HistoryState.Success(

app/src/main/java/com/bitcointxoko/gudariwallet/util/WalletConstants.kt

@@ -37,9 +37,9 @@ object WalletConstants {
     const val ALIAS_PREFS_KEY       = "alias_cache"
     const val ALIAS_PERSIST_TTL_MS  = 86_400_000L   // 24 hours — drop on load if older than this
     // ── Payments cache ────────────────────────────────────────────────────────
-    const val PAYMENTS_PREFS_NAME       = "payment_cache_prefs"
+//    const val PAYMENTS_PREFS_NAME       = "payment_cache_prefs"
-    const val PAYMENTS_PREFS_KEY        = "payment_list"
+//    const val PAYMENTS_PREFS_KEY        = "payment_list"
-    const val PAYMENTS_PREFS_SAVED_AT   = "payment_list_saved_at"
+//    const val PAYMENTS_PREFS_SAVED_AT   = "payment_list_saved_at"
     const val PAYMENTS_CACHE_TTL_MS     = 300_000L      // 5 minutes — show stale, refresh in background
     // ── Balance cache ─────────────────────────────────────────────────────────
     const val BALANCE_PREFS_NAME        = "balance_cache_prefs"

gradle.properties

@@ -12,4 +12,9 @@ org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
 # https://developer.android.com/r/tools/gradle-multi-project-decoupled-projects
 # org.gradle.parallel=true
 # Kotlin code style for this project: "official" or "obsolete":
-kotlin.code.style=official
+kotlin.code.style=official
+#Your project is using a version of the Android Gradle Plugin that has built-in Kotlin support,
+# which conflicts with how KSP tries to register its generated sources.
+# This tells AGP to allow KSP to use the kotlin.sourceSets DSL to register its generated code
+# (the Room-generated AppDatabase_Impl etc.), which it needs to do.
+android.disallowKotlinSourceSets=false

gradle/libs.versions.toml

@@ -19,6 +19,8 @@ retrofit = "3.0.0"
 zxing-embedded       = "4.3.0"
 navigationCompose = "2.8.9"
 appcompat = "1.7.0"
+ksp = "2.2.10-2.0.2"
+room = "2.7.1"
 
 
 
@@ -52,10 +54,14 @@ zxing-android-embedded          = { group = "com.journeyapps",         name = "z
 androidx-navigation-compose        = { group = "androidx.navigation", name = "navigation-compose",      version.ref = "navigationCompose" }
 androidx-lifecycle-runtime-compose = { group = "androidx.lifecycle", name = "lifecycle-runtime-compose" }
 androidx-appcompat = { group = "androidx.appcompat", name = "appcompat", version.ref = "appcompat" }
+room-runtime = { group = "androidx.room", name = "room-runtime", version.ref = "room" }
+room-ktx = { group = "androidx.room", name = "room-ktx", version.ref = "room" }
+room-compiler = { group = "androidx.room", name = "room-compiler", version.ref = "room" }
 
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }
 kotlin-android      = { id = "org.jetbrains.kotlin.android",   version.ref = "kotlin" }
 kotlin-compose = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
+ksp = { id = "com.google.devtools.ksp", version.ref = "ksp" }