feat: migrate lnurlcache to room

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

@@ -1,123 +1,110 @@
 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.LnurlScanResponse
+import com.bitcointxoko.gudariwallet.data.db.AppDatabase
+import com.bitcointxoko.gudariwallet.data.db.LnurlCacheEntity
 import com.bitcointxoko.gudariwallet.util.WalletConstants
-import com.google.gson.Gson
-import com.google.gson.reflect.TypeToken
 
 private const val TAG = "LnurlCacheRepository"
 
-data class LnurlCacheEntry(
-    val key      : String,
-    val response : LnurlScanResponse,
-    val savedAt  : Long
-)
-
 class LnurlCacheRepository(context: Context) {
 
-    private val prefs: SharedPreferences = context.getSharedPreferences(
+    private val dao = AppDatabase.getInstance(context).lnurlCacheDao()
-        WalletConstants.LNURL_CACHE_PREFS_NAME, Context.MODE_PRIVATE
+    private val gson = GsonProvider.gson
-    )
-    private val gson = Gson()
 
-    // In-memory map for fast access within a session
+    // Fast in-memory path — avoids a DB round-trip for keys already loaded
-    private val memCache = mutableMapOf<String, LnurlCacheEntry>()
+    // this session. Mirrors the pattern used in PaymentCacheRepository.
+    private val memCache = mutableMapOf<String, LnurlCacheEntity>()
 
-    init { loadFromDisk() }
+    // ── Public API ─────────────────────────────────────────────────────────────
 
     /**
      * Returns a cached [LnurlScanResponse] for [key], or null if:
      * - no entry exists
      * - the entry is older than [WalletConstants.LNURL_CACHE_TTL_MS]
-     * - the server marked the endpoint as disposable (null is treated as true per LUD-06)
+     * - the server marked the endpoint as disposable (null is treated as true
+     *   per LUD-06)
      */
-    fun get(key: String): LnurlScanResponse? {
+    suspend fun get(key: String): LnurlScanResponse? {
-        val entry = memCache[key] ?: return null
+        val entity = memCache[key] ?: dao.getByKey(key)?.also { memCache[key] = it }
-        val ageMs = System.currentTimeMillis() - entry.savedAt
+        ?: return null
 
+        val ageMs = System.currentTimeMillis() - entity.savedAt
         if (ageMs > WalletConstants.LNURL_CACHE_TTL_MS) {
             Log.d(TAG, "LNURL [CACHE STALE] $key (age ${ageMs / 1000}s)")
-            memCache.remove(key)
+            evict(key)
-            persistToDisk()
+            return null
+        }
+
+        val response = deserialise(entity.responseJson) ?: run {
+            Log.w(TAG, "LNURL [DESER ERR  ] $key — removing corrupt entry")
+            evict(key)
             return null
         }
 
         // LUD-06: disposable == null means treat as true — do not serve from cache
-        val disposable = entry.response.disposable
+        val disposable = response.disposable
-        if (disposable == null || disposable == true) {
+        if (disposable == true) {
             Log.d(TAG, "LNURL [DISPOSABLE ] $key — not serving from cache (disposable=$disposable)")
             return null
         }
 
         Log.d(TAG, "LNURL [CACHE HIT  ] $key (age ${ageMs / 1000}s)")
-        return entry.response
+        return response
     }
 
     /**
      * Stores [response] under [key].
      * Silently skips if the response is marked disposable (or disposable is null).
      */
-    fun put(key: String, response: LnurlScanResponse) {
+    suspend fun put(key: String, response: LnurlScanResponse) {
         val disposable = response.disposable
-        if (disposable == null || disposable == true) {
+        if ( disposable == true) {
             Log.d(TAG, "LNURL [SKIP CACHE ] $key — disposable=$disposable, not caching")
             return
         }
-        val entry = LnurlCacheEntry(key, response, System.currentTimeMillis())
+        val entity = LnurlCacheEntity(
-        memCache[key] = entry
+            key          = key,
-        persistToDisk()
+            responseJson = gson.toJson(response),
-        Log.d(TAG, "LNURL [CACHE SET  ] $key")
+            savedAt      = System.currentTimeMillis()
-    }
+        )
-
-    /**
-     * Removes the entry for [key] from both memory and disk.
-     * Called when a payment attempt with cached data fails, so the next
-     * scan will always fetch fresh metadata from the server.
-     */
-    fun invalidate(key: String) {
-        if (memCache.remove(key) != null) {
-            persistToDisk()
-            Log.d(TAG, "LNURL [INVALIDATED] $key")
-        }
-    }
-
-    fun clearAll() {
-        memCache.clear()
-        prefs.edit().clear().apply()
-        Log.d(TAG, "LNURL [CLEARED    ] all entries")
-    }
-
-    // ── Persistence ───────────────────────────────────────────────────────────
-
-    private fun loadFromDisk() {
-        val json = prefs.getString(WalletConstants.LNURL_CACHE_PREFS_KEY, null) ?: return
         runCatching {
-            val type = object : TypeToken<List<LnurlCacheEntry>>() {}.type
+            dao.insert(entity)
-            val list: List<LnurlCacheEntry> = gson.fromJson(json, type)
+            memCache[key] = entity
-            val now = System.currentTimeMillis()
+            Log.d(TAG, "LNURL [CACHE SET  ] $key")
-            var loaded = 0
-            list.forEach { entry ->
-                if (now - entry.savedAt < WalletConstants.LNURL_CACHE_TTL_MS) {
-                    memCache[entry.key] = entry
-                    loaded++
-                }
-            }
-            Log.d(TAG, "LNURL [LOADED     ] $loaded valid entries from disk (${list.size - loaded} expired)")
-        }.onFailure {
-            Log.w(TAG, "LNURL [LOAD ERR   ] ${it.message}")
-        }
-    }
-
-    private fun persistToDisk() {
-        runCatching {
-            prefs.edit()
-                .putString(WalletConstants.LNURL_CACHE_PREFS_KEY, gson.toJson(memCache.values.toList()))
-                .apply()
         }.onFailure {
             Log.w(TAG, "LNURL [PERSIST ERR] ${it.message}")
         }
     }
+
+    /**
+     * Removes the entry for [key] from both memory and DB.
+     * Called when a payment attempt with cached data fails, so the next
+     * scan will always fetch fresh metadata from the server.
+     */
+    suspend fun invalidate(key: String) {
+        evict(key)
+        Log.d(TAG, "LNURL [INVALIDATED] $key")
+    }
+
+    suspend fun clearAll() {
+        memCache.clear()
+        runCatching { dao.deleteAll() }
+            .onFailure { Log.w(TAG, "LNURL [CLEAR ERR  ] ${it.message}") }
+        Log.d(TAG, "LNURL [CLEARED    ] all entries")
+    }
+
+    // ── Helpers ────────────────────────────────────────────────────────────────
+
+    private suspend fun evict(key: String) {
+        memCache.remove(key)
+        runCatching { dao.deleteByKey(key) }
+    }
+
+    private fun deserialise(json: String): LnurlScanResponse? =
+        runCatching { gson.fromJson(json, LnurlScanResponse::class.java) }
+            .getOrNull()
 }

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

@@ -5,27 +5,48 @@ import androidx.room.Database
 import androidx.room.Room
 import androidx.room.RoomDatabase
 import androidx.room.TypeConverters
+import androidx.room.migration.Migration
+import androidx.sqlite.db.SupportSQLiteDatabase
 
 @Database(
-    entities = [PaymentRecordEntity::class],
+    entities = [PaymentRecordEntity::class, LnurlCacheEntity::class],
-    version = 1,
+    version = 2,
     exportSchema = false
 )
 @TypeConverters(PaymentConverters::class)
 abstract class AppDatabase : RoomDatabase() {
 
     abstract fun paymentDao(): PaymentDao
+    abstract fun lnurlCacheDao(): LnurlCacheDao
 
     companion object {
         @Volatile private var INSTANCE: AppDatabase? = null
 
+        private val MIGRATION_1_2 = object : Migration(1, 2) {
+            override fun migrate(db: SupportSQLiteDatabase) {
+                db.execSQL(
+                    """
+                    CREATE TABLE IF NOT EXISTS `lnurl_cache` (
+                        `key`          TEXT    NOT NULL,
+                        `responseJson` TEXT    NOT NULL,
+                        `savedAt`      INTEGER NOT NULL,
+                        PRIMARY KEY(`key`)
+                    )
+                    """.trimIndent()
+                )
+            }
+        }
+
         fun getInstance(context: Context): AppDatabase =
             INSTANCE ?: synchronized(this) {
                 INSTANCE ?: Room.databaseBuilder(
                     context.applicationContext,
                     AppDatabase::class.java,
                     "gudari_wallet.db"
-                ).build().also { INSTANCE = it }
+                )
+                    .addMigrations(MIGRATION_1_2)
+                    .build()
+                    .also { INSTANCE = it }
             }
     }
 }

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

@@ -0,0 +1,22 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import androidx.room.Dao
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+
+@Dao
+interface LnurlCacheDao {
+
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insert(entry: LnurlCacheEntity)
+
+    @Query("SELECT * FROM lnurl_cache WHERE `key` = :key LIMIT 1")
+    suspend fun getByKey(key: String): LnurlCacheEntity?
+
+    @Query("DELETE FROM lnurl_cache WHERE `key` = :key")
+    suspend fun deleteByKey(key: String)
+
+    @Query("DELETE FROM lnurl_cache")
+    suspend fun deleteAll()
+}

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

@@ -0,0 +1,12 @@
+package com.bitcointxoko.gudariwallet.data.db
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+
+@Entity(tableName = "lnurl_cache")
+data class LnurlCacheEntity(
+    @PrimaryKey
+    val key: String,          // the decoded LNURL / lightning-address string
+    val responseJson: String, // full LnurlScanResponse serialised as JSON
+    val savedAt: Long         // epoch ms — used for TTL check
+)

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

@@ -57,7 +57,6 @@ class WalletViewModelFactory(private val app: Application) : ViewModelProvider.F
         return WalletViewModel(
             repo,
             aliasRepo = aliasRepo,
-            lnurlCache = lnurlCache,
             paymentCache = paymentCache,
             balancePrefs = balancePrefs,
             balanceVm = balanceVm,

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

@@ -36,10 +36,9 @@ object WalletConstants {
     const val ALIAS_PREFS_NAME      = "alias_cache_prefs"
     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
+    // ── LNURL metadata cache ──────────────────────────────────────────────────
+    const val LNURL_CACHE_TTL_MS        = 7 * 24 * 60 * 60 * 1000L   // 7 days
     // ── Payments cache ────────────────────────────────────────────────────────
-//    const val PAYMENTS_PREFS_NAME       = "payment_cache_prefs"
-//    const val PAYMENTS_PREFS_KEY        = "payment_list"
-//    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
     // ── Payments sync ─────────────────────────────────────────────────────────────
     const val PAYMENTS_SYNC_CHECKPOINT  = 100   // max payments fetched on auto-sync at startup
@@ -49,8 +48,5 @@ object WalletConstants {
     const val BALANCE_PREFS_KEY         = "last_balance_sats"
     const val BALANCE_PREFS_SAVED_AT    = "last_balance_saved_at"
     const val BALANCE_CACHE_TTL_MS      = 3_600_000L              // 1 hour
-    // ── LNURL metadata cache ──────────────────────────────────────────────────
+
-    const val LNURL_CACHE_PREFS_NAME    = "lnurl_cache_prefs"
-    const val LNURL_CACHE_PREFS_KEY     = "lnurl_entries"
-    const val LNURL_CACHE_TTL_MS        = 3_600_000L   // 1 hour
 }