Can sign in user

lib/helpers/account_credentials_helper.dart

@@ -1,3 +1,8 @@
+import 'dart:convert';
+
+import 'package:comunic/models/login_tokens.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
 /// Accounts credentials helper
 ///
 /// Stores current account tokens
@@ -8,7 +13,27 @@ class AccountCredentialsHelper {
 
   /// Checkout whether current user is signed in or not
   Future<bool> signedIn() async {
-    return false; // TODO : implement
+    return await get() != null;
   }
 
+  /// Set new login tokens
+  Future<void> set(LoginTokens tokens) async {
+    SharedPreferences prefs = await SharedPreferences.getInstance();
+    await prefs.setString("login_tokens", tokens.toString());
+  }
+
+  /// Get current [LoginTokens]. Returns null if none or in case of failure
+  Future<LoginTokens> get() async {
+    try {
+
+      SharedPreferences prefs = await SharedPreferences.getInstance();
+      final string = prefs.getString("login_tokens");
+      if(string == null) return null;
+      return LoginTokens.fromJSON(jsonDecode(string));
+
+    } on Exception catch(e){
+      print(e.toString());
+      return null;
+    }
+  }
 }

lib/helpers/account_helper.dart

@@ -0,0 +1,41 @@
+import 'package:comunic/helpers/account_credentials_helper.dart';
+import 'package:comunic/helpers/api_helper.dart';
+import 'package:comunic/models/api_request.dart';
+import 'package:comunic/models/authentication_details.dart';
+import 'package:comunic/models/login_tokens.dart';
+
+/// Account helper
+///
+/// @author Pierre HUBERT
+
+enum AuthResult {
+  SUCCESS,
+  TOO_MANY_ATTEMPTS,
+  NETWORK_ERROR,
+  INVALID_CREDENTIALS
+}
+
+class AccountHelper {
+  /// Sign in user
+  Future<AuthResult> signIn(AuthenticationDetails auth) async {
+    final request = APIRequest(uri: "account/login");
+    request.addString("userMail", auth.email);
+    request.addString("userPassword", auth.password);
+
+    final response = await APIHelper().exec(request);
+
+    // Handle errors
+    if (response.code == 401)
+      return AuthResult.INVALID_CREDENTIALS;
+    else if (response.code == 429)
+      return AuthResult.TOO_MANY_ATTEMPTS;
+    else if (response.code != 200) return AuthResult.NETWORK_ERROR;
+
+    //Save login tokens
+    final tokensObj = response.getObject()["tokens"];
+    await AccountCredentialsHelper()
+        .set(LoginTokens(tokensObj["token1"], tokensObj["token2"]));
+
+    return AuthResult.SUCCESS;
+  }
+}

lib/helpers/api_helper.dart

@@ -0,0 +1,68 @@
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:comunic/models/api_request.dart';
+import 'package:comunic/models/api_response.dart';
+import 'package:comunic/models/config.dart';
+
+/// API Helper
+///
+/// @author Pierre HUBERT
+
+class APIHelper {
+  final _httpClient = HttpClient();
+
+  /// Execute a [request] on the server and returns a [APIResponse]
+  ///
+  /// This method should never throw but the response code of the [APIResponse]
+  /// should be verified before accessing response content
+  Future<APIResponse> exec(APIRequest request) async {
+    try {
+      //Add API tokens
+      request.addString("serviceName", config().serviceName);
+      request.addString("serviceToken", config().serviceToken);
+
+      //Add user tokens (if required)
+      if (request.needLogin) throw "Can add user tokens right now !";
+
+      // Prepare request body
+      String requestBody = "";
+      request.args.forEach((key, value) => requestBody +=
+          Uri.encodeQueryComponent(key) +
+              "=" +
+              Uri.encodeQueryComponent(value) +
+              "&");
+
+      List<int> bodyBytes = utf8.encode(requestBody);
+
+      // Determine server URL
+      final path = config().apiServerUri + request.uri;
+      Uri url;
+      if (!config().apiServerSecure)
+        url = Uri.http(config().apiServerName, path);
+      else
+        url = Uri.https(config().apiServerName, path);
+
+      //Connect to server
+      final connection = await _httpClient.postUrl(url);
+      connection.headers.set("Content-Length", bodyBytes.length.toString());
+      connection.headers
+          .set("Content-Type", "application/x-www-form-urlencoded");
+      connection.add(bodyBytes);
+
+      final response = await connection.close();
+
+      if (response.statusCode != HttpStatus.ok)
+        return APIResponse(response.statusCode, null);
+
+      //Save & return response
+      final responseBody = await response.transform(utf8.decoder).join();
+
+      return APIResponse(response.statusCode, responseBody);
+    } on Exception catch (e) {
+      print(e.toString());
+      print("Could not execute a request!");
+      return APIResponse(-1, null);
+    }
+  }
+}