refactor: migrate data storage from SharedPreferences to Room database

app/build.gradle.kts

@@ -2,6 +2,7 @@ plugins {
     alias(libs.plugins.android.application)
     alias(libs.plugins.kotlin.android)
     alias(libs.plugins.kotlin.compose)
+    alias(libs.plugins.ksp)
 }
 
 android {
@@ -85,4 +86,8 @@ dependencies {
     
     implementation("org.osmdroid:osmdroid-android:6.1.16")
     implementation("org.osmdroid:osmdroid-mapsforge:6.1.16")
+    
+    implementation(libs.androidx.room.runtime)
+    implementation(libs.androidx.room.ktx)
+    ksp(libs.androidx.room.compiler)
 }

app/src/main/java/org/noxylva/lbjconsole/database/TrainDatabase.kt

@@ -0,0 +1,35 @@
+package org.noxylva.lbjconsole.database
+
+import android.content.Context
+import androidx.room.Database
+import androidx.room.Room
+import androidx.room.RoomDatabase
+import androidx.room.migration.Migration
+import androidx.sqlite.db.SupportSQLiteDatabase
+
+@Database(
+    entities = [TrainRecordEntity::class],
+    version = 1,
+    exportSchema = false
+)
+abstract class TrainDatabase : RoomDatabase() {
+    
+    abstract fun trainRecordDao(): TrainRecordDao
+    
+    companion object {
+        @Volatile
+        private var INSTANCE: TrainDatabase? = null
+        
+        fun getDatabase(context: Context): TrainDatabase {
+            return INSTANCE ?: synchronized(this) {
+                val instance = Room.databaseBuilder(
+                    context.applicationContext,
+                    TrainDatabase::class.java,
+                    "train_database"
+                ).build()
+                INSTANCE = instance
+                instance
+            }
+        }
+    }
+}

app/src/main/java/org/noxylva/lbjconsole/database/TrainRecordDao.kt

@@ -0,0 +1,50 @@
+package org.noxylva.lbjconsole.database
+
+import androidx.room.*
+import kotlinx.coroutines.flow.Flow
+
+@Dao
+interface TrainRecordDao {
+    
+    @Query("SELECT * FROM train_records ORDER BY timestamp DESC")
+    suspend fun getAllRecords(): List<TrainRecordEntity>
+    
+    @Query("SELECT * FROM train_records ORDER BY timestamp DESC")
+    fun getAllRecordsFlow(): Flow<List<TrainRecordEntity>>
+    
+    @Query("SELECT * FROM train_records WHERE uniqueId = :uniqueId")
+    suspend fun getRecordById(uniqueId: String): TrainRecordEntity?
+    
+    @Query("SELECT COUNT(*) FROM train_records")
+    suspend fun getRecordCount(): Int
+    
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertRecord(record: TrainRecordEntity)
+    
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insertRecords(records: List<TrainRecordEntity>)
+    
+    @Delete
+    suspend fun deleteRecord(record: TrainRecordEntity)
+    
+    @Delete
+    suspend fun deleteRecords(records: List<TrainRecordEntity>)
+    
+    @Query("DELETE FROM train_records")
+    suspend fun deleteAllRecords()
+    
+    @Query("DELETE FROM train_records WHERE uniqueId = :uniqueId")
+    suspend fun deleteRecordById(uniqueId: String)
+    
+    @Query("DELETE FROM train_records WHERE uniqueId IN (:uniqueIds)")
+    suspend fun deleteRecordsByIds(uniqueIds: List<String>)
+    
+    @Query("SELECT * FROM train_records WHERE train LIKE '%' || :train || '%' AND route LIKE '%' || :route || '%' AND (:direction = '全部' OR (:direction = '上行' AND direction = 3) OR (:direction = '下行' AND direction = 1)) ORDER BY timestamp DESC")
+    suspend fun getFilteredRecords(train: String, route: String, direction: String): List<TrainRecordEntity>
+    
+    @Query("SELECT * FROM train_records ORDER BY timestamp DESC LIMIT :limit")
+    suspend fun getLatestRecords(limit: Int): List<TrainRecordEntity>
+    
+    @Query("SELECT * FROM train_records WHERE timestamp >= :fromTime ORDER BY timestamp DESC")
+    suspend fun getRecordsFromTime(fromTime: Long): List<TrainRecordEntity>
+}

app/src/main/java/org/noxylva/lbjconsole/database/TrainRecordEntity.kt

@@ -0,0 +1,66 @@
+package org.noxylva.lbjconsole.database
+
+import androidx.room.Entity
+import androidx.room.PrimaryKey
+import org.noxylva.lbjconsole.model.TrainRecord
+import org.json.JSONObject
+import java.util.*
+
+@Entity(tableName = "train_records")
+data class TrainRecordEntity(
+    @PrimaryKey val uniqueId: String,
+    val timestamp: Long,
+    val receivedTimestamp: Long,
+    val train: String,
+    val direction: Int,
+    val speed: String,
+    val position: String,
+    val time: String,
+    val loco: String,
+    val locoType: String,
+    val lbjClass: String,
+    val route: String,
+    val positionInfo: String,
+    val rssi: Double
+) {
+    fun toTrainRecord(): TrainRecord {
+        val jsonData = JSONObject().apply {
+            put("uniqueId", uniqueId)
+            put("timestamp", timestamp)
+            put("receivedTimestamp", receivedTimestamp)
+            put("train", train)
+            put("dir", direction)
+            put("speed", speed)
+            put("pos", position)
+            put("time", time)
+            put("loco", loco)
+            put("loco_type", locoType)
+            put("lbj_class", lbjClass)
+            put("route", route)
+            put("position_info", positionInfo)
+            put("rssi", rssi)
+        }
+        return TrainRecord(jsonData)
+    }
+    
+    companion object {
+        fun fromTrainRecord(record: TrainRecord): TrainRecordEntity {
+            return TrainRecordEntity(
+                uniqueId = record.uniqueId,
+                timestamp = record.timestamp.time,
+                receivedTimestamp = record.receivedTimestamp.time,
+                train = record.train,
+                direction = record.direction,
+                speed = record.speed,
+                position = record.position,
+                time = record.time,
+                loco = record.loco,
+                locoType = record.locoType,
+                lbjClass = record.lbjClass,
+                route = record.route,
+                positionInfo = record.positionInfo,
+                rssi = record.rssi
+            )
+        }
+    }
+}

app/src/main/java/org/noxylva/lbjconsole/model/TrainRecordManager.kt

@@ -7,6 +7,8 @@ import android.util.Log
 import kotlinx.coroutines.*
 import org.json.JSONArray
 import org.json.JSONObject
+import org.noxylva.lbjconsole.database.TrainDatabase
+import org.noxylva.lbjconsole.database.TrainRecordEntity
 import java.io.File
 import java.io.FileWriter
 import java.text.SimpleDateFormat
@@ -27,6 +29,8 @@ class TrainRecordManager(private val context: Context) {
     private val trainRecords = CopyOnWriteArrayList<TrainRecord>()
     private val recordCount = AtomicInteger(0)
     private val prefs: SharedPreferences = context.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+    private val database = TrainDatabase.getDatabase(context)
+    private val trainRecordDao = database.trainRecordDao()
     private val ioScope = CoroutineScope(Dispatchers.IO + SupervisorJob())
     
     var mergeSettings = MergeSettings()
@@ -34,11 +38,36 @@ class TrainRecordManager(private val context: Context) {
     
     init {
         ioScope.launch {
+            migrateFromSharedPreferences()
             loadRecords()
             loadMergeSettings()
         }
     }
     
+    private suspend fun migrateFromSharedPreferences() {
+        try {
+            val jsonStr = prefs.getString(KEY_RECORDS, null)
+            if (jsonStr != null && jsonStr != "[]") {
+                val jsonArray = JSONArray(jsonStr)
+                val records = mutableListOf<TrainRecordEntity>()
+                
+                for (i in 0 until jsonArray.length()) {
+                    val jsonObject = jsonArray.getJSONObject(i)
+                    val trainRecord = TrainRecord(jsonObject)
+                    records.add(TrainRecordEntity.fromTrainRecord(trainRecord))
+                }
+                
+                if (records.isNotEmpty()) {
+                    trainRecordDao.insertRecords(records)
+                    prefs.edit().remove(KEY_RECORDS).apply()
+                    Log.d(TAG, "Migrated ${records.size} records from SharedPreferences to Room database")
+                }
+            }
+        } catch (e: Exception) {
+            Log.e(TAG, "Failed to migrate records: ${e.message}")
+        }
+    }
+    
     
     private var filterTrain: String = ""
     private var filterRoute: String = ""
@@ -52,11 +81,16 @@ class TrainRecordManager(private val context: Context) {
         
         
         while (trainRecords.size > MAX_RECORDS) {
-            trainRecords.removeAt(trainRecords.size - 1)
+            val removedRecord = trainRecords.removeAt(trainRecords.size - 1)
+            ioScope.launch {
+                trainRecordDao.deleteRecordById(removedRecord.uniqueId)
+            }
         }
         
         recordCount.incrementAndGet()
-        saveRecords()
+        ioScope.launch {
+            trainRecordDao.insertRecord(TrainRecordEntity.fromTrainRecord(record))
+        }
         return record
     }
     
@@ -76,6 +110,16 @@ class TrainRecordManager(private val context: Context) {
         }
     }
     
+    suspend fun getFilteredRecordsFromDatabase(): List<TrainRecord> {
+        return try {
+            val entities = trainRecordDao.getFilteredRecords(filterTrain, filterRoute, filterDirection)
+            entities.map { it.toTrainRecord() }
+        } catch (e: Exception) {
+            Log.e(TAG, "Failed to get filtered records from database: ${e.message}")
+            emptyList()
+        }
+    }
+    
     
     private fun matchFilter(record: TrainRecord): Boolean {
         
@@ -118,32 +162,56 @@ class TrainRecordManager(private val context: Context) {
     }
     
     
+    suspend fun refreshRecordsFromDatabase() {
+        try {
+            val entities = trainRecordDao.getAllRecords()
+            trainRecords.clear()
+            entities.forEach { entity ->
+                trainRecords.add(entity.toTrainRecord())
+            }
+            recordCount.set(trainRecords.size)
+            Log.d(TAG, "Refreshed ${trainRecords.size} records from database")
+        } catch (e: Exception) {
+            Log.e(TAG, "Failed to refresh records from database: ${e.message}")
+        }
+    }
+    
+    
     fun clearRecords() {
         trainRecords.clear()
         recordCount.set(0)
-        saveRecords()
+        ioScope.launch {
+            trainRecordDao.deleteAllRecords()
+        }
     }
     
     fun deleteRecord(record: TrainRecord): Boolean {
         val result = trainRecords.remove(record)
         if (result) {
             recordCount.decrementAndGet()
-            saveRecords()
+            ioScope.launch {
+                trainRecordDao.deleteRecordById(record.uniqueId)
+            }
         }
         return result
     }
 
     fun deleteRecords(records: List<TrainRecord>): Int {
         var deletedCount = 0
+        val idsToDelete = mutableListOf<String>()
+        
         records.forEach { record ->
             if (trainRecords.remove(record)) {
                 deletedCount++
+                idsToDelete.add(record.uniqueId)
             }
         }
         
         if (deletedCount > 0) {
             recordCount.addAndGet(-deletedCount)
-            saveRecords()
+            ioScope.launch {
+                trainRecordDao.deleteRecordsByIds(idsToDelete)
+            }
         }
         return deletedCount
     }
@@ -151,12 +219,9 @@ class TrainRecordManager(private val context: Context) {
     private fun saveRecords() {
         ioScope.launch {
             try {
-                val jsonArray = JSONArray()
+                val entities = trainRecords.map { TrainRecordEntity.fromTrainRecord(it) }
-                for (record in trainRecords) {
+                trainRecordDao.insertRecords(entities)
-                    jsonArray.put(record.toJSON())
+                Log.d(TAG, "Saved ${trainRecords.size} records to database")
-                }
-                prefs.edit().putString(KEY_RECORDS, jsonArray.toString()).apply()
-                Log.d(TAG, "Saved ${trainRecords.size} records")
             } catch (e: Exception) {
                 Log.e(TAG, "Failed to save records: ${e.message}")
             }
@@ -164,19 +229,17 @@ class TrainRecordManager(private val context: Context) {
     }
     
     
-    private fun loadRecords() {
+    private suspend fun loadRecords() {
         try {
-            val jsonStr = prefs.getString(KEY_RECORDS, "[]")
+            val entities = trainRecordDao.getAllRecords()
-            val jsonArray = JSONArray(jsonStr)
             trainRecords.clear()
             
-            for (i in 0 until jsonArray.length()) {
+            entities.forEach { entity ->
-                val jsonObject = jsonArray.getJSONObject(i)
+                trainRecords.add(entity.toTrainRecord())
-                trainRecords.add(TrainRecord(jsonObject))
             }
             
             recordCount.set(trainRecords.size)
-            Log.d(TAG, "Loaded ${trainRecords.size} records")
+            Log.d(TAG, "Loaded ${trainRecords.size} records from database")
         } catch (e: Exception) {
             Log.e(TAG, "Failed to load records: ${e.message}")
         }
@@ -349,4 +412,41 @@ class TrainRecordManager(private val context: Context) {
             mergeSettings = MergeSettings()
         }
     }
+    
+    suspend fun exportRecordsToJson(): JSONArray {
+        val jsonArray = JSONArray()
+        try {
+            val entities = trainRecordDao.getAllRecords()
+            entities.forEach { entity ->
+                val record = entity.toTrainRecord()
+                jsonArray.put(record.toJSON())
+            }
+            Log.d(TAG, "Exported ${entities.size} records to JSON")
+        } catch (e: Exception) {
+            Log.e(TAG, "Failed to export records to JSON: ${e.message}")
+        }
+        return jsonArray
+    }
+    
+    suspend fun importRecordsFromJson(jsonArray: JSONArray): Int {
+        var importedCount = 0
+        try {
+            val records = mutableListOf<TrainRecordEntity>()
+            for (i in 0 until jsonArray.length()) {
+                val jsonObject = jsonArray.getJSONObject(i)
+                val trainRecord = TrainRecord(jsonObject)
+                records.add(TrainRecordEntity.fromTrainRecord(trainRecord))
+            }
+            
+            if (records.isNotEmpty()) {
+                trainRecordDao.insertRecords(records)
+                importedCount = records.size
+                refreshRecordsFromDatabase()
+                Log.d(TAG, "Imported $importedCount records from JSON")
+            }
+        } catch (e: Exception) {
+            Log.e(TAG, "Failed to import records from JSON: ${e.message}")
+        }
+        return importedCount
+    }
 }

gradle/libs.versions.toml

@@ -8,6 +8,7 @@ espressoCore = "3.6.1"
 lifecycleRuntimeKtx = "2.9.0"
 activityCompose = "1.10.1"
 composeBom = "2024.04.01"
+room = "2.6.1"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -24,9 +25,13 @@ androidx-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-toolin
 androidx-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-manifest" }
 androidx-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
 androidx-material3 = { group = "androidx.compose.material3", name = "material3" }
+androidx-room-runtime = { group = "androidx.room", name = "room-runtime", version.ref = "room" }
+androidx-room-compiler = { group = "androidx.room", name = "room-compiler", version.ref = "room" }
+androidx-room-ktx = { group = "androidx.room", name = "room-ktx", 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 = "2.0.0-1.0.21" }