Fix Fastpay SHow sdk when the app is not installed

sdk_initialize_screen.dart

import 'dart:io';

import 'package:fastpay_merchant/models/request/payment_initiation_request.dart';
import 'package:fastpay_merchant/ui/paymentScreen/payment_screen.dart';
import 'package:fastpay_merchant/ui/widget/text_style.dart';
import 'package:flutter/material.dart';
import 'package:flutter/scheduler.dart';
import 'package:flutter/services.dart';
import 'package:url_launcher/url_launcher.dart';

import '../../fastpay_flutter_sdk.dart';
import '../../models/fastpay_payment_response.dart';
import '../../models/request/payment_validate_request.dart';
import '../../models/response/payment_validate_response.dart';
import '../../services/fastpay_sdk_controller.dart';

class SdkInitializeScreen extends StatefulWidget {
  //final FastpayPaymentRequest fastpayPaymentRequest;

  const SdkInitializeScreen({super.key});

  @override
  State<SdkInitializeScreen> createState() => _SdkInitializeScreenState();
}

class _SdkInitializeScreenState extends State<SdkInitializeScreen>
    with WidgetsBindingObserver {
  String titleText = "Initiating...";

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    super.didChangeAppLifecycleState(state);

    if (state == AppLifecycleState.resumed) {
      SchedulerBinding.instance.addPostFrameCallback((_) {
        PaymentValidateRequest request = PaymentValidateRequest(
            FastpayFlutterSdk.instance.fastpayPaymentRequest?.stroreId ?? '',
            FastpayFlutterSdk.instance.fastpayPaymentRequest?.storePassword ??
                '',
            FastpayFlutterSdk.instance.fastpayPaymentRequest?.orderID ?? '');
        FastpaySdkController.instance.paymentValidate(request,
            (response) async {
          if (response.status?.toLowerCase() == "success") {
            var fastpayResult = FastpayPaymentResponse(
                "success",
                response.gwTransactionId,
                FastpayFlutterSdk.instance.fastpayPaymentRequest?.orderID ?? '',
                FastpayFlutterSdk.instance.fastpayPaymentRequest?.amount,
                "IQD",
                response.customerName,
                response.customerMobileNumber,
                DateTime.now().microsecondsSinceEpoch.toString());
            FastpayFlutterSdk.instance.dispose(fastpayResult);
            FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
                SDKStatus.SUCCESS, 'Payment success',
                result: fastpayResult);
          } else {
            FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback
                ?.call(SDKStatus.FAILED, 'Payment failed');
            FastpayFlutterSdk.instance.dispose(null);
          }
        }, onFailed: (_, error) {
          FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback
              ?.call(SDKStatus.CANCEL, error);
          FastpayFlutterSdk.instance.dispose(null);
        });
      });
    }
  }

  @override
  void initState() {
    WidgetsBinding.instance.addObserver(this);
    super.initState();
    FastpayFlutterSdk.instance.startTimer();
    var paymentRequest = FastpayFlutterSdk.instance.fastpayPaymentRequest;
    var errorList = <String>[];
    if (paymentRequest?.stroreId == null ||
        paymentRequest?.stroreId.isEmpty == true) {
      //FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(SDKStatus.CANCEL,'Order id is empty');
      errorList.add('Store id is empty');
    }
    if (paymentRequest?.storePassword == null ||
        paymentRequest?.storePassword.isEmpty == true) {
      errorList.add('Store password is empty');
    }
    if (paymentRequest?.orderID == null ||
        paymentRequest?.orderID.isEmpty == true) {
      errorList.add('Order id is empty');
    }
    if (paymentRequest?.amount == null ||
        paymentRequest?.amount.isEmpty == true) {
      errorList.add('Amount is empty');
    }
    if (errorList.isEmpty) {
      FastpaySdkController.instance.initPayment(
          PaymentInitiationRequest(
              paymentRequest?.stroreId ?? '',
              paymentRequest?.storePassword ?? '',
              paymentRequest?.amount ?? '',
              paymentRequest?.orderID ?? '',
              'IQD'), (response) async {
        try {
          if (Platform.isAndroid) {
            setState(() {
              titleText = "Waiting for payment completion..";
            });
            FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
              SDKStatus.PAYMENT_WITH_FASTPAY_APP,
              'Payment is redirected to fastpay application',
            );
            final Uri _url = Uri.parse(
              'appFpp://fast-pay.cash/qrpay?qrData=${response.qrToken}&redirect_url=sdk://fp.com&order_id=${paymentRequest?.orderID ?? ''}',
            );
            final bool canOpenAndroidFastPayApp = await launchUrl(_url);
            if (canOpenAndroidFastPayApp) {
              FastpayFlutterSdk.instance.dispose(null);
            } else {
              FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
                SDKStatus.PAYMENT_WITH_FASTPAY_SDK,
                'Fastpay payment processing with fastpay SDK',
              );
              Navigator.of(context).pushReplacement(
                MaterialPageRoute(builder: (_) => PaymentScreen(response)),
              );
            }
          } else {
            setState(() {
              titleText = "Waiting for payment completion..";
            });

            FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
              SDKStatus.PAYMENT_WITH_FASTPAY_APP,
              'Payment is redirected to fastpay application',
            );
            final Uri _url = Uri.parse(
              'appFpp://fast-pay.cash/qrpay?qrdata=${response.qrToken}&clientUri=${FastpayFlutterSdk.instance.fastpayPaymentRequest?.callbackUriIos}&transactionId=${paymentRequest?.orderID ?? ''}',
            );
            final bool canOpenFastPayApp = await launchUrl(_url);
            if (canOpenFastPayApp) {
              FastpayFlutterSdk.instance.dispose(null);
            } else {
              FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
                SDKStatus.PAYMENT_WITH_FASTPAY_SDK,
                'Fastpay payment processing with fastpay SDK',
              );
              Navigator.of(context).pushReplacement(
                MaterialPageRoute(builder: (_) => PaymentScreen(response)),
              );
            }
          }
        } catch (e) {
          FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
            SDKStatus.PAYMENT_WITH_FASTPAY_SDK,
            'Fastpay payment processing with fastpay SDK',
          );
          Navigator.of(context).pushReplacement(
            MaterialPageRoute(builder: (_) => PaymentScreen(response)),
          );
        }
      }, onFailed: (code, message) {
        FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
          SDKStatus.CANCEL,
          'Payment initialization failed',
        );
        Navigator.pop(context);
      });
    } else {
      FastpayFlutterSdk.instance.fastpayPaymentRequest?.callback?.call(
        SDKStatus.CANCEL,
        errorList.join(","),
      );
      Navigator.pop(context);
    }
  }

  @override
  void dispose() {
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.landscapeRight,
      DeviceOrientation.landscapeLeft,
      DeviceOrientation.portraitUp,
      DeviceOrientation.portraitDown,
    ]);
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.portraitUp,
      DeviceOrientation.portraitDown,
    ]);

    return SafeArea(
        child: Scaffold(
      body: Container(
        width: MediaQuery.of(context).size.width,
        height: MediaQuery.of(context).size.height,
        color: Colors.white,
        child: Padding(
          padding:
              EdgeInsets.only(top: MediaQuery.of(context).size.width / 1.5),
          child: Column(
            children: [
              Image.asset(
                AssetImage("asset/ic_logo.png").assetName,
                package: 'fastpay_merchant',
                width: MediaQuery.of(context).size.width / 3,
              ),
              const SizedBox(
                height: 25,
              ),
              Text(
                titleText,
                style: getTextStyle(textSize: 12),
              )
            ],
          ),
        ),
      ),
    ));
  }
}