Store locally the list of conversations

lib/helpers/database/conversations_database_helper.dart

@@ -0,0 +1,20 @@
+import 'package:comunic/helpers/database/database_contract.dart';
+import 'package:comunic/helpers/database/model_database_helper.dart';
+import 'package:comunic/models/conversation.dart';
+
+/// Conversations database helper
+///
+/// @author Pierre HUBERT
+
+class ConversationsDatabaseHelper extends ModelDatabaseHelper<Conversation> {
+  @override
+  Conversation initializeFromMap(Map<String, dynamic> map) {
+    return Conversation.fromMap(map);
+  }
+
+  @override
+  String tableName() {
+    return ConversationTableContract.TABLE_NAME;
+  }
+
+}

lib/helpers/database/database_contract.dart

@@ -22,4 +22,16 @@ abstract class UserTableContract {
   static const C_VISIBILITY  = "visibility";
   static const C_VIRTUAL_DIRECTORY = "virtual_directory";
   static const C_ACCOUNT_IMAGE_URL = "account_image_url";
+}
+
+/// Conversations table contract
+abstract class ConversationTableContract {
+  static const TABLE_NAME = "conversations";
+  static const C_ID = BaseTableContract.C_ID;
+  static const C_OWNER_ID = "owner_id";
+  static const C_LAST_ACTIVE = "last_active";
+  static const C_NAME = "name";
+  static const C_FOLLOWING = "following";
+  static const C_SAW_LAST_MESSAGE = "saw_last_message";
+  static const C_MEMBERS = "members";
 }

lib/helpers/database/database_helper.dart

@@ -34,7 +34,14 @@ abstract class DatabaseHelper {
   /// Currently : delete all the database tables and initialize it again
   static Future<void> _performDatabaseUpdate(
       Database db, int oldVersion, int newVersion) async {
-    //Initialize database again
+    // Drop users table
+    await db.execute("DROP TABLE IF EXISTS ${UserTableContract.TABLE_NAME}");
+
+    // Drop conversations table
+    await db
+        .execute("DROP TABLE IF EXISTS ${ConversationTableContract.TABLE_NAME}");
+
+    // Initialize database again
     await _initializeDatabase(db, newVersion);
   }
 
@@ -45,9 +52,20 @@ abstract class DatabaseHelper {
         "${UserTableContract.C_ID} INTEGER PRIMARY KEY, "
         "${UserTableContract.C_FIRST_NAME} TEXT, "
         "${UserTableContract.C_LAST_NAME} TEXT, "
-        "${UserTableContract.C_VISIBILITY} TEXT,"
-        "${UserTableContract.C_VIRTUAL_DIRECTORY} TEXT,"
+        "${UserTableContract.C_VISIBILITY} TEXT, "
+        "${UserTableContract.C_VIRTUAL_DIRECTORY} TEXT, "
         "${UserTableContract.C_ACCOUNT_IMAGE_URL} TEXT"
         ")");
+
+    //Create conversations table
+    await db.execute("CREATE TABLE ${ConversationTableContract.TABLE_NAME} ("
+        "${ConversationTableContract.C_ID} INTEGER PRIMARY KEY, "
+        "${ConversationTableContract.C_OWNER_ID} INTEGER, "
+        "${ConversationTableContract.C_LAST_ACTIVE} INTEGER, "
+        "${ConversationTableContract.C_NAME} TEXT, "
+        "${ConversationTableContract.C_FOLLOWING} INTEGER, "
+        "${ConversationTableContract.C_SAW_LAST_MESSAGE} INTEGER, "
+        "${ConversationTableContract.C_MEMBERS} TEXT"
+        ")");
   }
 }

lib/helpers/database/model_database_helper.dart

@@ -9,7 +9,6 @@ import 'package:comunic/models/cache_model.dart';
 /// @author Pierre HUBERT
 
 abstract class ModelDatabaseHelper<T extends CacheModel> {
-
   /// Get the name of the target table. Must be specified by the children
   /// of this class
   String tableName();
@@ -19,8 +18,7 @@ abstract class ModelDatabaseHelper<T extends CacheModel> {
 
   /// Insert an entry in the database
   Future<void> _insertDB(T el) async {
-    await (await DatabaseHelper.get())
-        .insert(tableName(), el.toMap());
+    await (await DatabaseHelper.get()).insert(tableName(), el.toMap());
   }
 
   /// Update an element in the database
@@ -48,6 +46,11 @@ abstract class ModelDatabaseHelper<T extends CacheModel> {
     return null;
   }
 
+  /// Empty the table
+  Future<void> clearTable() async {
+    await (await DatabaseHelper.get()).execute("DELETE FROM ${tableName()}");
+  }
+
   /// Check out whether an element specified with its [id] is present
   /// or not in the local database
   Future<bool> has(int id) async {
@@ -65,8 +68,13 @@ abstract class ModelDatabaseHelper<T extends CacheModel> {
 
   /// Insert or update an important amount of elements
   Future<void> insertOrUpdateAll(List<T> list) async {
-    for(int i = 0; i < list.length; i++)
-      await insertOrUpdate(list[i]);
+    for (int i = 0; i < list.length; i++) await insertOrUpdate(list[i]);
   }
 
-}
+  /// Insert  an important amount of elements
+  ///
+  /// This might throw if there are conflicting IDs
+  Future<void> insertAll(List<T> list) async {
+    for (T el in list) await _insertDB(el);
+  }
+}