Add disk storage for Vault Timeout (#518)

app/src/main/java/com/x8bit/bitwarden/data/platform/datasource/disk/BaseDiskSource.kt

@@ -10,6 +10,37 @@ import androidx.core.content.edit
 abstract class BaseDiskSource(
     private val sharedPreferences: SharedPreferences,
 ) {
+    /**
+     * Gets the [Int] for the given [key] from [SharedPreferences], or return the [default] value
+     * if that key is not present.
+     */
+    protected fun getInt(
+        key: String,
+        default: Int? = null,
+    ): Int? =
+        if (sharedPreferences.contains(key)) {
+            sharedPreferences.getInt(key, 0)
+        } else {
+            // Make sure we can return a null value as a default if necessary
+            default
+        }
+
+    /**
+     * Puts the [value] in [SharedPreferences] for the given [key] (or removes the key when the
+     * value is `null`).
+     */
+    protected fun putInt(
+        key: String,
+        value: Int?,
+    ): Unit =
+        sharedPreferences.edit {
+            if (value != null) {
+                putInt(key, value)
+            } else {
+                remove(key)
+            }
+        }
+
     protected fun getString(
         key: String,
         default: String? = null,

app/src/main/java/com/x8bit/bitwarden/data/platform/datasource/disk/SettingsDiskSource.kt

@@ -0,0 +1,25 @@
+package com.x8bit.bitwarden.data.platform.datasource.disk
+
+import kotlinx.coroutines.flow.Flow
+
+/**
+ * Primary access point for general settings-related disk information.
+ */
+interface SettingsDiskSource {
+    /**
+     * Gets the current vault timeout (in minutes) for the given [userId] (or `null` if the vault
+     * should never time out).
+     */
+    fun getVaultTimeoutInMinutes(userId: String): Int?
+
+    /**
+     * Emits updates that track [getVaultTimeoutInMinutes] for the given [userId]. This will replay
+     * the last known value, if any.
+     */
+    fun getVaultTimeoutInMinutesFlow(userId: String): Flow<Int?>
+
+    /**
+     * Stores the given [vaultTimeoutInMinutes] for the given [userId].
+     */
+    fun storeVaultTimeoutInMinutes(userId: String, vaultTimeoutInMinutes: Int?)
+}

app/src/main/java/com/x8bit/bitwarden/data/platform/datasource/disk/SettingsDiskSourceImpl.kt

@@ -0,0 +1,46 @@
+package com.x8bit.bitwarden.data.platform.datasource.disk
+
+import android.content.SharedPreferences
+import com.x8bit.bitwarden.data.platform.datasource.disk.BaseDiskSource.Companion.BASE_KEY
+import com.x8bit.bitwarden.data.platform.repository.util.bufferedMutableSharedFlow
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableSharedFlow
+import kotlinx.coroutines.flow.onSubscription
+
+private const val VAULT_TIME_IN_MINUTES_KEY = "$BASE_KEY:vaultTimeout"
+
+/**
+ * Primary implementation of [SettingsDiskSource].
+ */
+class SettingsDiskSourceImpl(
+    val sharedPreferences: SharedPreferences,
+) : BaseDiskSource(sharedPreferences = sharedPreferences),
+    SettingsDiskSource {
+    private val mutableVaultTimeoutInMinutesFlowMap =
+        mutableMapOf<String, MutableSharedFlow<Int?>>()
+
+    override fun getVaultTimeoutInMinutes(userId: String): Int? =
+        getInt(key = "${VAULT_TIME_IN_MINUTES_KEY}_$userId")
+
+    override fun getVaultTimeoutInMinutesFlow(userId: String): Flow<Int?> =
+        getMutableVaultTimeoutInMinutesFlow(userId = userId)
+            .onSubscription { emit(getVaultTimeoutInMinutes(userId = userId)) }
+
+    override fun storeVaultTimeoutInMinutes(
+        userId: String,
+        vaultTimeoutInMinutes: Int?,
+    ) {
+        putInt(
+            key = "${VAULT_TIME_IN_MINUTES_KEY}_$userId",
+            value = vaultTimeoutInMinutes,
+        )
+        getMutableVaultTimeoutInMinutesFlow(userId = userId).tryEmit(vaultTimeoutInMinutes)
+    }
+
+    private fun getMutableVaultTimeoutInMinutesFlow(
+        userId: String,
+    ): MutableSharedFlow<Int?> =
+        mutableVaultTimeoutInMinutesFlowMap.getOrPut(userId) {
+            bufferedMutableSharedFlow(replay = 1)
+        }
+}