import 'dart:convert'; import 'package:flutter/cupertino.dart'; import 'package:http/http.dart'; import '../../../models/gas_refill/gas_refill_model.dart'; import '../../../models/user.dart'; import '../../api_routes/urls.dart'; class GasRefillProvider extends ChangeNotifier { // number of items call in each request final pageItemNumber = 50; //reset provider data void reset() { items = null; nextPage = true; stateCode = null; } // state code of current request to defied error message // like 400 customer request failed // 500 service not available int? stateCode; // true if there is next page in product list and false if not bool nextPage = true; // list of user requests List? items; // when requests in-process _loading = true // done _loading = true // failed _loading = false bool? isLoading; /// return -2 if request in progress /// return -1 if error happen when sending request /// return state code if request complete may be 200, 404 or 403 /// for more details check http state manager /// lib\controllers\http_status_manger\http_status_manger.dart Future getRequests({ required String host, required User user, }) async { if (isLoading == true) { return -2; } isLoading = true; Response response; try { response = await get( Uri.parse("$host${URLs.getGasRefill}?uid=${user.id}" "&token=${user.token}&page=${(items?.length ?? 0) ~/ pageItemNumber}"), headers: {"Content-Type": "application/json; charset=utf-8"}); stateCode = response.statusCode; if (stateCode != null && stateCode! >= 200 && stateCode! < 300) { // client's request was successfully received List requestsListJson = json.decode(utf8.decode(response.bodyBytes)); List itemsPage = requestsListJson .map((request) => GasRefillModel.fromJson(request)) .toList(); items ??= []; items?.addAll(itemsPage); if (itemsPage.length == pageItemNumber) { nextPage = true; } else { nextPage = false; } } isLoading = false; notifyListeners(); return response.statusCode; } catch (error) { isLoading = false; stateCode = -1; notifyListeners(); return -1; } } Future createModel({ required String host, required User user, required GasRefillModel model, }) async { Map body = { "uid": user.id.toString(), "token": user.token ?? "", "title": model.title ?? "", "status": "0", //model.status.value.toString(), }; body["details"] = jsonEncode(model.details ?.map((model) => { "type": model.type?.id.toString(), "size": model.cylinderSize?.id.toString(), "requsted_qty": model.requestedQuantity.toString(), }) .toList()); Response response; try { response = await post( Uri.parse(host + URLs.requestGasRefill), body: body, ); stateCode = response.statusCode; if (response.statusCode >= 200 && response.statusCode < 300) { final items = this.items; if (items != null) { items.insert( 0, GasRefillModel.fromJson( json.decode(utf8.decode(response.bodyBytes))[0])); notifyListeners(); } } return response.statusCode; } catch (error) { return -1; } } Future updateModel({ required String host, required User user, required GasRefillModel oldModel, required GasRefillModel newModel, }) async { Map body = { "uid": user.id.toString(), "token": user.token, "title": newModel.title ?? "", "status": newModel.status?.id.toString(), }; body["details"] = jsonEncode(newModel.details ?.map((model) => { "type": model.type?.id.toString(), "size": model.cylinderSize?.id.toString(), "requsted_qty": model.requestedQuantity.toString(), "deliverd_qty": model.deliveredQuantity.toString(), }) .toList()); Response response; try { response = await post( Uri.parse("$host${URLs.updateGasRefill}/${newModel.id}"), body: body, ); stateCode = response.statusCode; if (response.statusCode >= 200 && response.statusCode < 300) { oldModel.fromGasRefillModel(newModel); notifyListeners(); } return response.statusCode; } catch (error) { return -1; } } }