velocity-pay-flutter/lib/screens/integration/integration_screen.dart

import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:provider/provider.dart';
import 'package:qpay/screens/gateway/gateway_controller.dart';
import 'package:qpay/screens/transaction_controller.dart';
import 'package:skeletonizer/skeletonizer.dart';

import 'integration_controller.dart';

class IntegrationScreen extends StatefulWidget {
  const IntegrationScreen({super.key});

  @override
  State<IntegrationScreen> createState() => _IntegrationScreenState();
}

class _IntegrationScreenState extends State<IntegrationScreen> {
  late IntegrationController controller;
  late TransactionController transactionController;
  late GatewayController gatewayController;

  bool integrating = false;

  @override
  void initState() {
    super.initState();
    controller = IntegrationController(context);
    gatewayController = GatewayController(context);
    transactionController = Provider.of<TransactionController>(
      context,
      listen: false,
    );

  }

  @override
  void didChangeDependencies() async {
    super.didChangeDependencies();

    if(integrating) return;

    String status = Provider.of<TransactionController>(context).model.paymentStatus;
    if(status == 'SUCCESS') {
      setState(() {
        integrating = true;
      });
      await controller.doIntegration();
    }
  }

  void _showErrorSnackBar(String? message) {
    WidgetsBinding.instance.addPostFrameCallback((_) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text(message.toString()),
          behavior: SnackBarBehavior.floating,
          backgroundColor: Colors.deepOrange,
        ),
      );
    });
  }


  @override
  void dispose() {
    controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Completing your transaction'),
      ),
      body: ListenableBuilder(
        listenable: gatewayController,
        builder: (context, child) {
          return ListenableBuilder(
            listenable: controller,
            builder: (context, child) {
              if (controller.model.status == 'SUCCESS') {
                WidgetsBinding.instance.addPostFrameCallback((_) {
                  context.go('/receipt');
                });
              }

              return Container(
                padding: EdgeInsets.all(50),
                child: Center(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.center,
                    children: [
                      SizedBox(height: 75),

                      if(transactionController.model.paymentStatus != 'SUCCESS')
                      Column(
                        children: [
                          Text(
                            'We failed to check your payment status',
                            style: TextStyle(fontSize: 20),
                            textAlign: TextAlign.center,
                          ),
                          SizedBox(height: 50,),
                          Skeletonizer(
                            enabled: gatewayController.model.isLoading,
                            child: OutlinedButton(
                              child: Text('Check latest status'),
                              onPressed: () {
                                gatewayController.poll(transactionController.model.receiptData?['id']);
                              },
                            ),
                          ),
                        ],
                      ),

                      if(transactionController.model.paymentStatus == 'SUCCESS')
                      Column(
                        children: [
                          Text(
                            'We\'ve successfully collected your funds. We are now '
                                'updating your billing account. This won\'t take long',
                            style: TextStyle(fontSize: 20),
                            textAlign: TextAlign.center,
                          ),
                          Image.asset('assets/peak-animation.gif', width: 150),
                          SizedBox(
                            width: 50,
                            child: LinearProgressIndicator(),
                          ),
                          SizedBox(height: 50),
                          if(controller.model.status == 'FAILED')
                          Column(
                            children: [
                              Text(
                                'We failed to update your billing account',
                                style: TextStyle(fontSize: 20),
                                textAlign: TextAlign.center,
                              ),
                              SizedBox(height: 20,),
                              Skeletonizer(
                                enabled: controller.model.isLoading,
                                child: OutlinedButton(
                                  child: Text('Retry'),
                                  onPressed: () {
                                    controller.doIntegration();
                                  },
                                ),
                              ),
                            ],
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
              );
            },
          );
        }
      ),
    );
  }
}