From 26a86de7fc67663e221cd7ba160f368043da2bec Mon Sep 17 00:00:00 2001
From: MohammadTaha Basiri <m.taha.basiri@gmail.com>
Date: Sun, 12 Dec 2021 18:37:11 +0330
Subject: [PATCH] D1APP-22 configuration (network services)

---
 lib/services/request_handler.dart | 175 ++++++++++++++++++++++++++++++
 1 file changed, 175 insertions(+)
 create mode 100644 lib/services/request_handler.dart

diff --git a/lib/services/request_handler.dart b/lib/services/request_handler.dart
new file mode 100644
index 0000000..462ee4d
--- /dev/null
+++ b/lib/services/request_handler.dart
@@ -0,0 +1,175 @@
+import 'dart:convert';
+import 'dart:developer';
+import 'dart:io';
+import 'package:http/http.dart' as http;
+
+class RequestHandler {
+  static late String token;
+
+  String? errorMessage;
+
+  dynamic body;
+  final Map<String, String> _headers = {
+    "accept": "*/*",
+    "Content-Type": "application/json; charset=UTF-8",
+  };
+  final String url;
+  dynamic _requestBody;
+
+  bool isSuccess = false;
+
+  RequestHandler(
+    this.url, {
+    Map<String, String>? requestHeaders,
+    body,
+    bool useAutherization = true,
+  }) {
+    if (body != null) _requestBody = body;
+    if (requestHeaders != null) _headers.addAll(requestHeaders);
+    if (useAutherization) _headers.addAll({'Authorization': 'Bearer $token'});
+    if (body != null) _requestBody = body;
+  }
+
+  Future<void> httpGet() async {
+    try {
+      final response = await http
+          .get(
+            Uri.parse(url),
+            headers: _headers,
+          )
+          .timeout(
+            const Duration(seconds: 10),
+          )
+          .catchError(
+            (e) => throw e,
+          );
+      _handleResponse(response);
+    } catch (e) {
+      _handleError(null);
+    }
+  }
+
+  Future<void> post() async {
+    try {
+      final response = await http
+          .post(
+            Uri.parse(url),
+            body: json.encode(_requestBody),
+            headers: _headers,
+          )
+          .timeout(
+            const Duration(seconds: 10),
+          )
+          .catchError(
+            (e) => throw e,
+          );
+      _handleResponse(response);
+    } catch (e) {
+      _handleError(null);
+    }
+  }
+
+  Future<void> delete() async {
+    try {
+      final response = await http
+          .delete(
+            Uri.parse(url),
+            body: json.encode(_requestBody),
+            headers: _headers,
+          )
+          .timeout(
+            const Duration(seconds: 10),
+          )
+          .catchError(
+            (e) => throw e,
+          );
+      _handleResponse(response);
+    } catch (e) {
+      _handleError(null);
+    }
+  }
+
+  Future<void> multipart(File file) async {
+    try {
+      final request = http.MultipartRequest('POST', Uri.parse(url));
+      _headers.update('Content-Type', (_) => 'multipart/form-data');
+      request.headers.addAll(_headers);
+      request.files.add(
+        http.MultipartFile(
+          'file',
+          file.readAsBytes().asStream(),
+          file.lengthSync(),
+          filename: 'desc',
+        ),
+      );
+      final streamedResponse = await request
+          .send()
+          .timeout(
+            const Duration(seconds: 10),
+          )
+          .catchError(
+            (e) => throw e,
+          );
+      final response = await http.Response.fromStream(streamedResponse);
+      _handleResponse(response);
+    } catch (e) {
+      _handleError(null);
+    }
+  }
+
+  Future<void> put() async {
+    try {
+      final response = await http
+          .put(
+            Uri.parse(url),
+            body: json.encode(_requestBody),
+            headers: _headers,
+          )
+          .timeout(
+            const Duration(seconds: 10),
+          )
+          .catchError(
+            (e) => throw e,
+          );
+      _handleResponse(response);
+    } catch (e) {
+      _handleError(null);
+    }
+  }
+
+  void _handleResponse(http.Response? response) {
+    if (_handleError(response)) {
+      if (response!.body.isNotEmpty) {
+        body = json.decode(response.body);
+      }
+    }
+  }
+
+  bool _handleError(http.Response? response) {
+    if (response == null) {
+      log(
+        'Connecion failed or request timedout! ("$url")',
+        name: 'Request fail error',
+      );
+      isSuccess = false;
+      errorMessage = _errorMessageGenerator(response);
+      return false;
+    }
+    if (response.statusCode != 200 && response.statusCode != 204) {
+      log(
+        'Request to [$url] failed with status code ${response.statusCode} & result : \n ${response.body.isNotEmpty ? json.decode(response.body) : 'No result.'}',
+        name: 'Request fail error',
+      );
+      isSuccess = false;
+      errorMessage = _errorMessageGenerator(response);
+      return false;
+    }
+    isSuccess = true;
+    return true;
+  }
+
+  String _errorMessageGenerator(http.Response? response) {
+    //TODO: Needs implementation
+    return '';
+  }
+}