Do not use SQLite anymore for users

lib/enums/user_page_visibility.dart

@@ -3,12 +3,3 @@
 /// @author Pierre HUBERT
 
 enum UserPageVisibility { PRIVATE, PUBLIC, OPEN }
-
-/// Find the visibility level matching a string
-UserPageVisibility userPageVisibilityFromString(String str) {
-  for (int i = 0; i < UserPageVisibility.values.length; i++)
-    if (UserPageVisibility.values[i].toString() == str)
-      return UserPageVisibility.values[i];
-
-  throw "$str is not a valid user page visibility level!";
-}

lib/generated_plugin_registrant.dart

@@ -5,12 +5,13 @@
 // ignore_for_file: lines_longer_than_80_chars
 
 import 'package:file_picker/src/file_picker_web.dart';
-import 'package:flutter_web_plugins/flutter_web_plugins.dart';
 import 'package:shared_preferences_web/shared_preferences_web.dart';
 import 'package:url_launcher_web/url_launcher_web.dart';
 import 'package:video_player_web/video_player_web.dart';
 import 'package:wakelock_web/wakelock_web.dart';
 
+import 'package:flutter_web_plugins/flutter_web_plugins.dart';
+
 // ignore: public_member_api_docs
 void registerPlugins(Registrar registrar) {
   FilePickerWeb.registerWith(registrar);

lib/helpers/database/database_contract.dart

@@ -13,18 +13,6 @@ abstract class BaseTableContract {
   static const C_ID = "id";
 }
 
-/// User table contract
-abstract class UserTableContract {
-  static const TABLE_NAME = "users";
-  static const C_ID = BaseTableContract.C_ID;
-  static const C_FIRST_NAME = "first_name";
-  static const C_LAST_NAME = "last_name";
-  static const C_VISIBILITY = "visibility";
-  static const C_VIRTUAL_DIRECTORY = "virtual_directory";
-  static const C_ACCOUNT_IMAGE_URL = "account_image_url";
-  static const C_CUSTOM_EMOJIES = "custom_emojies";
-}
-
 /// Friends table contract
 abstract class FriendsListTableContract {
   static const TABLE_NAME = "friends";

lib/helpers/database/database_helper.dart

@@ -1,5 +1,4 @@
 import 'package:comunic/helpers/database/database_contract.dart';
-import 'package:connectivity/connectivity.dart';
 import 'package:path/path.dart';
 import 'package:sqflite/sqflite.dart';
 
@@ -30,21 +29,11 @@ abstract class DatabaseHelper {
     return _db;
   }
 
-  /// Cleanup database
-  static Future<void> cleanUpDatabase() async {
-    // If connected to a network, cleanup user information
-    if (await Connectivity().checkConnectivity() != ConnectivityResult.none)
-      await _db.execute("DELETE FROM ${UserTableContract.TABLE_NAME}");
-  }
-
   /// Perform database update
   ///
   /// Currently : delete all the database tables and initialize it again
   static Future<void> _performDatabaseUpdate(
       Database db, int oldVersion, int newVersion) async {
-    // Drop users table
-    await db.execute("DROP TABLE IF EXISTS ${UserTableContract.TABLE_NAME}");
-
     // Drop friends list table
     await db
         .execute("DROP TABLE IF EXISTS ${FriendsListTableContract.TABLE_NAME}");
@@ -55,17 +44,6 @@ abstract class DatabaseHelper {
 
   /// Initialize the database
   static Future<void> _initializeDatabase(Database db, int version) async {
-    // Create users table
-    await db.execute("CREATE TABLE ${UserTableContract.TABLE_NAME} ("
-        "${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, "
-        "${UserTableContract.C_ACCOUNT_IMAGE_URL} TEXT, "
-        "${UserTableContract.C_CUSTOM_EMOJIES} TEXT"
-        ")");
-
     // Friends list table
     await db.execute("CREATE TABLE ${FriendsListTableContract.TABLE_NAME} ("
         "${FriendsListTableContract.C_ID} INTEGER PRIMARY KEY, "

lib/helpers/database/users_database_helper.dart

@@ -1,24 +0,0 @@
-import 'package:comunic/helpers/database/model_database_helper.dart';
-import 'package:comunic/models/user.dart';
-
-import 'database_contract.dart';
-
-/// User database helper
-///
-/// @author Pierre HUBERT
-
-class UsersDatabaseHelper extends ModelDatabaseHelper<User> {
-
-
-  @override
-  String tableName() {
-    return UserTableContract.TABLE_NAME;
-  }
-
-  @override
-  User initializeFromMap(Map<String, dynamic> map) {
-    return User.fromMap(map);
-  }
-
-
-}

lib/helpers/serialization/base_serialization_helper.dart

@@ -102,6 +102,8 @@ abstract class BaseSerializationHelper<T extends SerializableElement> {
     return _cache.any((element) => isContained(element));
   }
 
+  Future<bool> has(T el) => any((t) => t == el);
+
   /// Check if any entry in the last match the predicate
   Future<T> first(bool filter(T t)) async {
     await _loadCache();
@@ -120,10 +122,26 @@ abstract class BaseSerializationHelper<T extends SerializableElement> {
     await _saveCache();
   }
 
+  /// Insert or replace many elements
+  Future<void> insertOrReplaceElements(List<T> list) async {
+    await _loadCache();
+
+    _cache.removeWhere((element) => list.any((newEl) => element == newEl));
+    _cache.addAll(list);
+
+    await _saveCache();
+  }
+
   /// Remove elements
   Future<void> removeElement(bool isToRemove(T t)) async {
     await _loadCache();
     _cache.removeWhere((element) => isToRemove(element));
     await _saveCache();
   }
+
+  /// Remove all elements
+  Future<void> removeAll() async {
+    _cache = [];
+    await _saveCache();
+  }
 }

lib/helpers/serialization/user_list_serialization_helper.dart

@@ -0,0 +1,28 @@
+import 'package:comunic/helpers/serialization/base_serialization_helper.dart';
+import 'package:comunic/models/user.dart';
+
+/// User serialization helper
+///
+/// @author Pierre Hubert
+
+UsersListSerialisationHelper _singleton;
+
+class UsersListSerialisationHelper extends BaseSerializationHelper<User> {
+  UsersListSerialisationHelper._();
+
+  factory UsersListSerialisationHelper() {
+    if (_singleton == null) _singleton = UsersListSerialisationHelper._();
+
+    return _singleton;
+  }
+
+  @override
+  String get type => "users-list";
+
+  @override
+  User parse(Map<String, dynamic> m) => User.fromJson(m);
+
+  /// Remove a user by its ID
+  Future<void> removeUserByID(int userID) =>
+      removeElement((t) => t.id == userID);
+}

lib/helpers/users_helper.dart

@@ -1,5 +1,5 @@
 import 'package:comunic/enums/user_page_visibility.dart';
-import 'package:comunic/helpers/database/users_database_helper.dart';
+import 'package:comunic/helpers/serialization/user_list_serialization_helper.dart';
 import 'package:comunic/lists/custom_emojies_list.dart';
 import 'package:comunic/lists/users_list.dart';
 import 'package:comunic/models/advanced_user_info.dart';
@@ -27,7 +27,6 @@ class GetUserAdvancedUserError extends Error {
 }
 
 class UsersHelper {
-  final UsersDatabaseHelper _usersDatabaseHelper = UsersDatabaseHelper();
 
   /// Download information about some given users ID
   ///
@@ -64,7 +63,7 @@ class UsersHelper {
         );
 
     // Save the list
-    _usersDatabaseHelper.insertOrUpdateAll(list);
+    await UsersListSerialisationHelper().insertOrReplaceElements(list);
 
     return list;
   }
@@ -114,8 +113,8 @@ class UsersHelper {
 
     // Check cache
     for (int userID in users) {
-      if (!forceDownload && await _usersDatabaseHelper.has(userID))
-        list.add(await _usersDatabaseHelper.get(userID));
+      if (!forceDownload && await UsersListSerialisationHelper().any((u) => u.id == userID))
+        list.add(await UsersListSerialisationHelper().first((u) => u.id == userID));
       else
         toDownload.add(userID);
     }

lib/main.dart

@@ -1,10 +1,12 @@
 import 'package:comunic/helpers/account_helper.dart';
 import 'package:comunic/helpers/database/database_helper.dart';
 import 'package:comunic/helpers/preferences_helper.dart';
+import 'package:comunic/helpers/serialization/user_list_serialization_helper.dart';
 import 'package:comunic/helpers/version_helper.dart';
 import 'package:comunic/ui/widgets/init_widget.dart';
 import 'package:comunic/utils/flutter_utils.dart';
 import 'package:comunic/utils/intl_utils.dart';
+import 'package:connectivity/connectivity.dart';
 import 'package:flutter/material.dart';
 
 /// Main file of the application
@@ -18,9 +20,11 @@ void subMain() async {
   await VersionHelper.ensureLoaded();
 
   // Connect to database
-  if(!isWeb) {
+  if (!isWeb) {
     await DatabaseHelper.open();
-    await DatabaseHelper.cleanUpDatabase();
+
+    if (await Connectivity().checkConnectivity() != ConnectivityResult.none)
+      await UsersListSerialisationHelper().removeAll();
   }
 
   // Get current system language

lib/models/user.dart

@@ -1,9 +1,8 @@
 import 'dart:convert';
 
 import 'package:comunic/enums/user_page_visibility.dart';
-import 'package:comunic/helpers/database/database_contract.dart';
+import 'package:comunic/helpers/serialization/base_serialization_helper.dart';
 import 'package:comunic/lists/custom_emojies_list.dart';
-import 'package:comunic/models/cache_model.dart';
 import 'package:comunic/utils/ui_utils.dart';
 import 'package:meta/meta.dart';
 
@@ -11,7 +10,8 @@ import 'package:meta/meta.dart';
 ///
 /// @author Pierre HUBERT
 
-class User extends CacheModel {
+class User implements SerializableElement<User> {
+  final int id;
   final String firstName;
   final String lastName;
   final UserPageVisibility pageVisibility;
@@ -20,7 +20,7 @@ class User extends CacheModel {
   final CustomEmojiesList customEmojies;
 
   const User({
-    @required int id,
+    @required this.id,
     @required this.firstName,
     @required this.lastName,
     @required this.pageVisibility,
@@ -28,12 +28,12 @@ class User extends CacheModel {
     @required this.accountImageURL,
     @required this.customEmojies,
   })  : assert(id != null),
+        assert(id > 0),
         assert(firstName != null),
         assert(lastName != null),
         assert(pageVisibility != null),
         assert(accountImageURL != null),
-        assert(customEmojies != null),
-        super(id: id);
+        assert(customEmojies != null);
 
   /// Get user full name
   String get fullName => firstName + " " + lastName;
@@ -44,27 +44,27 @@ class User extends CacheModel {
   bool get hasVirtualDirectory =>
       virtualDirectory != null && virtualDirectory.length > 0;
 
-  Map<String, dynamic> toMap() {
-    return {
-      UserTableContract.C_ID: id,
-      UserTableContract.C_FIRST_NAME: firstName,
-      UserTableContract.C_LAST_NAME: lastName,
-      UserTableContract.C_VISIBILITY: pageVisibility.toString(),
-      UserTableContract.C_VIRTUAL_DIRECTORY: virtualDirectory,
-      UserTableContract.C_ACCOUNT_IMAGE_URL: accountImageURL,
-      UserTableContract.C_CUSTOM_EMOJIES:
-          jsonEncode(customEmojies.toSerializableList()),
+  Map<String, dynamic> toJson() => {
+        "id": id,
+        "firstName": firstName,
+        "lastName": lastName,
+        "pageVisibility": pageVisibility.toString(),
+        "virtualDirectory": virtualDirectory,
+        "accountImageURL": accountImageURL,
+        "customEmojies": customEmojies.toSerializableList()
       };
-  }
 
-  User.fromMap(Map<String, dynamic> map)
-      : this.firstName = map[UserTableContract.C_FIRST_NAME],
-        this.lastName = map[UserTableContract.C_LAST_NAME],
-        this.pageVisibility =
-            userPageVisibilityFromString(map[UserTableContract.C_VISIBILITY]),
-        this.virtualDirectory = map[UserTableContract.C_VIRTUAL_DIRECTORY],
-        this.accountImageURL = map[UserTableContract.C_ACCOUNT_IMAGE_URL],
+  User.fromJson(Map<String, dynamic> map)
+      : this.id = map["id"],
+        this.firstName = map["firstName"],
+        this.lastName = map["lastName"],
+        this.pageVisibility = UserPageVisibility.values.firstWhere(
+            (element) => element.toString() == map["pageVisibility"]),
+        this.virtualDirectory = map["virtualDirectory"],
+        this.accountImageURL = map["accountImageURL"],
         this.customEmojies = CustomEmojiesList.fromSerializedList(
-            jsonDecode(map[UserTableContract.C_CUSTOM_EMOJIES])),
-        super.fromMap(map);
+            jsonDecode(map["customEmojies"]));
+
+  @override
+  int compareTo(User other) => id.compareTo(other.id);
 }

lib/ui/routes/settings/account_image_settings.dart

@@ -1,4 +1,4 @@
-import 'package:comunic/helpers/database/users_database_helper.dart';
+import 'package:comunic/helpers/serialization/user_list_serialization_helper.dart';
 import 'package:comunic/helpers/settings_helper.dart';
 import 'package:comunic/models/account_image_settings.dart';
 import 'package:comunic/ui/dialogs/multi_choices_dialog.dart';
@@ -38,7 +38,7 @@ class _AccountImageSettingsScreenState
   @override
   void dispose() {
     // Remove current user information to force refresh of account image
-    UsersDatabaseHelper().delete(userID());
+    UsersListSerialisationHelper().removeUserByID(userID());
 
     super.dispose();
   }

lib/ui/routes/settings/general_account_settings.dart

@@ -1,5 +1,5 @@
 import 'package:comunic/enums/user_page_visibility.dart';
-import 'package:comunic/helpers/database/users_database_helper.dart';
+import 'package:comunic/helpers/serialization/user_list_serialization_helper.dart';
 import 'package:comunic/helpers/settings_helper.dart';
 import 'package:comunic/models/general_settings.dart';
 import 'package:comunic/ui/dialogs/multi_choices_dialog.dart';
@@ -34,7 +34,7 @@ class _GeneralAccountSettingsScreenState
   @override
   void dispose() {
     // Remove current user information to force refresh of account image
-    UsersDatabaseHelper().delete(userID());
+    UsersListSerialisationHelper().removeUserByID(userID());
 
     super.dispose();
   }