Add backing infra for Room

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

app/src/main/java/dev/msfjarvis/todo/data/source/DateTimeTypeConverters.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package dev.msfjarvis.todo.data.source
+
+import androidx.room.TypeConverter
+import java.time.LocalDateTime
+import java.time.format.DateTimeFormatter
+
+object DateTimeTypeConverters {
+  @TypeConverter
+  @JvmStatic
+  fun toLocalDateTime(value: String?): LocalDateTime? {
+    return value?.let { LocalDateTime.parse(value) }
+  }
+
+  @TypeConverter
+  @JvmStatic
+  fun fromLocalDateTime(value: LocalDateTime?): String? {
+    return value?.format(DateTimeFormatter.ISO_LOCAL_DATE_TIME)
+  }
+}

app/src/main/java/dev/msfjarvis/todo/data/source/TodoDatabase.kt

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+package dev.msfjarvis.todo.data.source
+
+import androidx.room.Database
+import androidx.room.RoomDatabase
+import androidx.room.TypeConverters
+import dev.msfjarvis.todo.data.model.TodoItem
+
+@Database(
+  entities = [
+    TodoItem::class,
+  ],
+  version = 1,
+  exportSchema = false,
+)
+@TypeConverters(DateTimeTypeConverters::class)
+abstract class TodoDatabase : RoomDatabase() {
+  abstract fun todoItemsDao(): TodoItemDao
+}

app/src/main/java/dev/msfjarvis/todo/data/source/TodoItemDao.kt

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+package dev.msfjarvis.todo.data.source
+
+import androidx.room.Dao
+import androidx.room.Delete
+import androidx.room.Insert
+import androidx.room.OnConflictStrategy
+import androidx.room.Query
+import androidx.room.Update
+import dev.msfjarvis.todo.data.model.TodoItem
+import kotlinx.coroutines.flow.Flow
+
+/**
+ * Room [Dao] for [TodoItem]
+ */
+@Dao
+abstract class TodoItemDao {
+
+  @Query("SELECT * FROM todo_items")
+  abstract fun getAllItems(): Flow<List<TodoItem>>
+
+  @Insert(onConflict = OnConflictStrategy.REPLACE)
+  abstract suspend fun insert(entity: TodoItem): Long
+
+  @Insert(onConflict = OnConflictStrategy.REPLACE)
+  abstract suspend fun insertAll(vararg entity: TodoItem)
+
+  @Insert(onConflict = OnConflictStrategy.REPLACE)
+  abstract suspend fun insertAll(entities: Collection<TodoItem>)
+
+  @Update(onConflict = OnConflictStrategy.REPLACE)
+  abstract suspend fun update(entity: TodoItem)
+
+  @Delete
+  abstract suspend fun delete(entity: TodoItem): Int
+}