#8: Global refactoring (#13)

* use StateList, models refactoring

* Caching with Room, NetworkStatus implemented

* Added user agent

* fix Key [CurrencyCode] was already used

java.lang.IllegalArgumentException: Key TRX was already used. If you are using LazyColumn/Row please make sure you provide a unique key for each item.

* Format amount input

* Fix api links

app/build.gradle

@@ -75,17 +75,25 @@ android {
 }
 
 dependencies {
-    implementation 'com.squareup.moshi:moshi-kotlin:1.14.0'
-    kapt 'com.squareup.moshi:moshi-kotlin-codegen:1.14.0'
-    implementation "com.squareup.okhttp3:okhttp:5.0.0-alpha.3"
     implementation "androidx.compose.ui:ui:$compose_version"
-    implementation 'io.coil-kt:coil:2.2.1'
-    implementation 'io.coil-kt:coil-gif:2.2.1'
-    implementation 'io.coil-kt:coil-compose:2.2.1'
+    implementation "androidx.navigation:navigation-compose:2.5.2"
+    implementation "com.google.accompanist:accompanist-navigation-animation:0.27.0"
     implementation "androidx.compose.material:material:$compose_version"
     implementation "androidx.compose.ui:ui-tooling-preview:$compose_version"
     implementation 'androidx.lifecycle:lifecycle-runtime-ktx:2.5.1'
     implementation 'androidx.activity:activity-compose:1.5.1'
+
+    implementation "com.google.dagger:dagger:2.42"
+    kapt "com.google.dagger:dagger-compiler:2.42"
+
+    implementation "androidx.room:room-runtime:2.4.3"
+    implementation "androidx.room:room-ktx:2.4.3"
+    kapt "androidx.room:room-compiler:2.4.3"
+
+    implementation 'com.squareup.retrofit2:retrofit:2.9.0'
+    implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
+    implementation 'com.squareup.okhttp3:logging-interceptor:4.9.1'
+
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.3'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'

app/src/main/AndroidManifest.xml

@@ -3,10 +3,11 @@
     xmlns:tools="http://schemas.android.com/tools"
     package="space.taran.arkrate">
 
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
     <uses-permission android:name="android.permission.INTERNET" />
 
     <application
-        android:name=".App"
+        android:name=".presentation.App"
         android:allowBackup="true"
         android:dataExtractionRules="@xml/data_extraction_rules"
         android:fullBackupContent="@xml/backup_rules"
@@ -18,7 +19,7 @@
         android:usesCleartextTraffic="true"
         tools:targetApi="31">
         <activity
-            android:name=".MainActivity"
+            android:name=".presentation.MainActivity"
             android:exported="true"
             android:theme="@style/Theme.Exchange">
             <intent-filter>

app/src/main/java/space/taran/arkrate/data/CurrencyAmount.kt

@@ -0,0 +1,6 @@
+package space.taran.arkrate.data
+
+data class CurrencyAmount(
+    val code: String,
+    var amount: Double
+)

app/src/main/java/space/taran/arkrate/data/CurrencyName.kt

@@ -0,0 +1,6 @@
+package space.taran.arkrate.data
+
+data class CurrencyName(
+    val code: String,
+    val name: String
+)

app/src/main/java/space/taran/arkrate/data/CurrencyRate.kt

@@ -0,0 +1,6 @@
+package space.taran.arkrate.data
+
+data class CurrencyRate(
+    val code: String,
+    val rate: Double
+)

app/src/main/java/space/taran/arkrate/data/CurrencyRepo.kt

@@ -0,0 +1,56 @@
+package space.taran.arkrate.data
+
+import android.util.Log
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.sync.Mutex
+import space.taran.arkrate.data.db.CurrencyRateLocalDataSource
+import space.taran.arkrate.data.db.FetchTimestampDataSource
+import space.taran.arkrate.data.network.NetworkStatus
+import space.taran.arkrate.utils.withContextAndLock
+import java.util.concurrent.TimeUnit
+
+abstract class CurrencyRepo(
+    private val local: CurrencyRateLocalDataSource,
+    private val networkStatus: NetworkStatus,
+    private val fetchTimestampDataSource: FetchTimestampDataSource
+) {
+    protected abstract val type: CurrencyType
+    private var currencyRates: List<CurrencyRate>? = null
+    private var updatedTS: Long? = null
+    private val mutex = Mutex()
+
+    suspend fun getCurrencyRate(): List<CurrencyRate> =
+        withContextAndLock(Dispatchers.IO, mutex) {
+            if (!networkStatus.isOnline()) {
+                currencyRates = local.getByType(type)
+                return@withContextAndLock currencyRates!!
+            }
+
+            updatedTS ?: let {
+                updatedTS = fetchTimestampDataSource.getTimestamp(type)
+            }
+
+            if (
+                updatedTS == null ||
+                updatedTS!! + dayInMillis < System.currentTimeMillis()
+            ) {
+                currencyRates = fetchRemote()
+                launch { fetchTimestampDataSource.rememberTimestamp(type) }
+                launch { local.insert(currencyRates!!, type) }
+                updatedTS = System.currentTimeMillis()
+            }
+
+            currencyRates ?: let {
+                currencyRates = local.getByType(type)
+            }
+            Log.d("Test", "${currencyRates!!.sortedBy { it.code }}")
+            return@withContextAndLock currencyRates!!
+        }
+
+    protected abstract suspend fun fetchRemote(): List<CurrencyRate>
+
+    abstract suspend fun getCurrencyName(): List<CurrencyName>
+
+    private val dayInMillis = TimeUnit.DAYS.toMillis(1)
+}

app/src/main/java/space/taran/arkrate/data/CurrencyType.kt

@@ -0,0 +1,5 @@
+package space.taran.arkrate.data
+
+enum class CurrencyType {
+    FIAT, CRYPTO
+}

app/src/main/java/space/taran/arkrate/data/GeneralCurrencyRepo.kt

@@ -0,0 +1,27 @@
+package space.taran.arkrate.data
+
+import space.taran.arkrate.data.crypto.CryptoCurrencyRepo
+import space.taran.arkrate.data.fiat.FiatCurrencyRepo
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class GeneralCurrencyRepo @Inject constructor(
+    val fiatRepo: FiatCurrencyRepo,
+    val cryptoRepo: CryptoCurrencyRepo
+) {
+    private val currencyRepos = listOf(
+        fiatRepo,
+        cryptoRepo
+    )
+
+    suspend fun getCurrencyRate(): List<CurrencyRate> =
+        currencyRepos.fold(emptyList()) { codeToRate, repo ->
+            codeToRate + repo.getCurrencyRate()
+        }
+
+    suspend fun getCurrencyName(): List<CurrencyName> =
+        currencyRepos.fold(emptyList()) { currencyName, repo ->
+            currencyName + repo.getCurrencyName()
+        }
+}

app/src/main/java/space/taran/arkrate/data/assets/AssetsRepo.kt

@@ -0,0 +1,60 @@
+package space.taran.arkrate.data.assets
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.SharedFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import space.taran.arkrate.data.CurrencyAmount
+import space.taran.arkrate.data.db.AssetsLocalDataSource
+import space.taran.arkrate.utils.replace
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class AssetsRepo @Inject constructor(
+    private val local: AssetsLocalDataSource
+) {
+    private var currencyAmountList = listOf<CurrencyAmount>()
+    private val currencyAmountFlow =
+        MutableStateFlow<List<CurrencyAmount>>(emptyList())
+    private val scope = CoroutineScope(Dispatchers.IO)
+
+    init {
+        scope.launch {
+            currencyAmountList = local.getAll()
+            currencyAmountFlow.emit(currencyAmountList)
+        }
+    }
+
+    fun allCurrencyAmount(): List<CurrencyAmount> = currencyAmountList
+
+    fun allCurrencyAmountFlow(): StateFlow<List<CurrencyAmount>> = currencyAmountFlow
+
+    suspend fun setCurrencyAmount(code: String, amount: Double) =
+        withContext(Dispatchers.IO) {
+            currencyAmountList.find {
+                it.code == code
+            }?.let { currencyAmount ->
+                currencyAmountList = currencyAmountList.replace(
+                    currencyAmount,
+                    currencyAmount.copy(amount = amount)
+                )
+            } ?: let {
+                currencyAmountList =
+                    currencyAmountList + CurrencyAmount(code, amount)
+            }
+            currencyAmountFlow.emit(currencyAmountList.toList())
+            local.insert(CurrencyAmount(code, amount))
+        }
+
+    suspend fun removeCurrency(code: String) = withContext(Dispatchers.IO) {
+        currencyAmountList.find { it.code == code }?.let {
+            currencyAmountList = currencyAmountList - it
+        }
+        currencyAmountFlow.emit(currencyAmountList)
+        local.delete(code)
+    }
+}

app/src/main/java/space/taran/arkrate/data/crypto/CryptoAPI.kt

@@ -0,0 +1,8 @@
+package space.taran.arkrate.data.crypto
+
+import retrofit2.http.GET
+
+interface CryptoAPI {
+    @GET("/ARK-Builders/ark-exchange-rates/main/crypto-rates.json")
+    suspend fun getCryptoRates(): List<CryptoRateResponse>
+}

app/src/main/java/space/taran/arkrate/data/crypto/CryptoCurrencyRepo.kt

@@ -0,0 +1,39 @@
+package space.taran.arkrate.data.crypto
+
+import space.taran.arkrate.data.CurrencyName
+import space.taran.arkrate.data.CurrencyRate
+import space.taran.arkrate.data.CurrencyRepo
+import space.taran.arkrate.data.CurrencyType
+import space.taran.arkrate.data.network.NetworkStatus
+import space.taran.arkrate.data.db.CurrencyRateLocalDataSource
+import space.taran.arkrate.data.db.FetchTimestampDataSource
+import javax.inject.Inject
+import javax.inject.Singleton
+
+@Singleton
+class CryptoCurrencyRepo @Inject constructor(
+    private val cryptoAPI: CryptoAPI,
+    private val local: CurrencyRateLocalDataSource,
+    private val networkStatus: NetworkStatus,
+    private val fetchTimestampDataSource: FetchTimestampDataSource
+) : CurrencyRepo(local, networkStatus, fetchTimestampDataSource) {
+    override val type = CurrencyType.CRYPTO
+
+    override suspend fun fetchRemote(): List<CurrencyRate> =
+        cryptoAPI.getCryptoRates().findUSDTPairs()
+
+    override suspend fun getCurrencyName(): List<CurrencyName> =
+        getCurrencyRate().map {
+            CurrencyName(it.code, name = "")
+        }
+
+    // api returns pairs like ETHBTC, ETHBNB, ETHTRX, ETHUSDT
+    // we only take USDT pairs
+    private fun List<CryptoRateResponse>.findUSDTPairs() =
+        mapNotNull { (code, price) ->
+            if (code.takeLast(4) == "USDT") {
+                CurrencyRate(code.dropLast(4), price)
+            } else
+                null
+        }
+}

app/src/main/java/space/taran/arkrate/data/crypto/CryptoRatesResponse.kt

@@ -0,0 +1,6 @@
+package space.taran.arkrate.data.crypto
+
+data class CryptoRateResponse(
+    val symbol: String,
+    val price: Double
+)

app/src/main/java/space/taran/arkrate/data/db/AssetsDao.kt

@@ -0,0 +1,41 @@
+package space.taran.arkrate.data.db
+
+import androidx.room.Dao
+import androidx.room.Entity
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.PrimaryKey
+import androidx.room.Query
+import space.taran.arkrate.data.CurrencyAmount
+import javax.inject.Inject
+
+@Entity
+data class RoomCurrencyAmount(
+    @PrimaryKey
+    val code: String,
+    val amount: Double
+)
+
+@Dao
+interface AssetsDao {
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insert(currencyAmount: RoomCurrencyAmount)
+
+    @Query("SELECT * FROM RoomCurrencyAmount")
+    suspend fun getAll(): List<RoomCurrencyAmount>
+
+    @Query("DELETE FROM RoomCurrencyAmount where code = :code")
+    suspend fun delete(code: String)
+}
+
+class AssetsLocalDataSource @Inject constructor(val dao: AssetsDao) {
+    suspend fun insert(currencyAmount: CurrencyAmount) =
+        dao.insert(currencyAmount.toRoom())
+
+    suspend fun getAll() = dao.getAll().map { it.toCurrencyAmount() }
+
+    suspend fun delete(code: String) = dao.delete(code)
+}
+
+private fun RoomCurrencyAmount.toCurrencyAmount() = CurrencyAmount(code, amount)
+private fun CurrencyAmount.toRoom() = RoomCurrencyAmount(code, amount)

app/src/main/java/space/taran/arkrate/data/db/CurrencyRateDao.kt

@@ -0,0 +1,42 @@
+package space.taran.arkrate.data.db
+
+import androidx.room.Dao
+import androidx.room.Entity
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.PrimaryKey
+import androidx.room.Query
+import space.taran.arkrate.data.CurrencyRate
+import space.taran.arkrate.data.CurrencyType
+import javax.inject.Inject
+
+@Entity
+data class RoomCurrencyRate(
+    @PrimaryKey
+    val code: String,
+    val currencyType: String,
+    val rate: Double
+)
+
+@Dao
+interface CurrencyRateDao {
+    @Insert(onConflict = OnConflictStrategy.REPLACE)
+    suspend fun insert(currencyRate: List<RoomCurrencyRate>)
+
+    @Query("SELECT * FROM RoomCurrencyRate where currencyType = :currencyType")
+    suspend fun getByType(currencyType: String): List<RoomCurrencyRate>
+}
+
+class CurrencyRateLocalDataSource @Inject constructor(val dao: CurrencyRateDao) {
+    suspend fun insert(
+        currencyRate: List<CurrencyRate>,
+        currencyType: CurrencyType
+    ) = dao.insert(currencyRate.map { it.toRoom(currencyType) })
+
+    suspend fun getByType(currencyType: CurrencyType) =
+        dao.getByType(currencyType.name).map { it.toCurrencyRate() }
+}
+
+private fun RoomCurrencyRate.toCurrencyRate() = CurrencyRate(code, rate)
+private fun CurrencyRate.toRoom(currencyType: CurrencyType) =
+    RoomCurrencyRate(code, currencyType.name, rate)