Basics for user prefs, logging in, etc

app/src/main/java/com/github/damontecres/dolphin/preferences/UserPreferencesSeralizer.kt

@@ -0,0 +1,27 @@
+package com.github.damontecres.dolphin.preferences
+
+import androidx.datastore.core.CorruptionException
+import androidx.datastore.core.Serializer
+import com.google.protobuf.InvalidProtocolBufferException
+import java.io.InputStream
+import java.io.OutputStream
+import javax.inject.Inject
+
+class UserPreferencesSerializer
+    @Inject
+    constructor() : Serializer<UserPreferences> {
+        override val defaultValue: UserPreferences = UserPreferences.getDefaultInstance()
+
+        override suspend fun readFrom(input: InputStream): UserPreferences {
+            try {
+                return UserPreferences.parseFrom(input)
+            } catch (exception: InvalidProtocolBufferException) {
+                throw CorruptionException("Cannot read proto.", exception)
+            }
+        }
+
+        override suspend fun writeTo(
+            t: UserPreferences,
+            output: OutputStream,
+        ) = t.writeTo(output)
+    }