ente/lib/ui/subscription_page.dart

import 'dart:async';
import 'dart:io';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_inappwebview/flutter_inappwebview.dart';
import 'package:in_app_purchase/in_app_purchase.dart';
import 'package:logging/logging.dart';
import 'package:photos/core/event_bus.dart';
import 'package:photos/events/subscription_purchased_event.dart';
import 'package:photos/models/billing_plan.dart';
import 'package:photos/models/subscription.dart';
import 'package:photos/services/billing_service.dart';
import 'package:photos/ui/loading_widget.dart';
import 'package:photos/utils/data_util.dart';
import 'package:photos/utils/dialog_util.dart';
import 'package:photos/utils/toast_util.dart';
import 'package:progress_dialog/progress_dialog.dart';
import 'package:url_launcher/url_launcher.dart';

class SubscriptionPage extends StatefulWidget {
  const SubscriptionPage({Key key}) : super(key: key);

  @override
  _SubscriptionPageState createState() => _SubscriptionPageState();
}

class _SubscriptionPageState extends State<SubscriptionPage> {
  final _logger = Logger("SubscriptionPage");
  final _billingService = BillingService.instance;
  Subscription _currentSubscription;
  StreamSubscription _purchaseUpdateSubscription;
  ProgressDialog _dialog;
  Future<int> _usageFuture;
  bool _hasActiveSubscription;

  @override
  void initState() {
    _billingService.setIsOnSubscriptionPage(true);
    _currentSubscription = _billingService.getSubscription();
    _hasActiveSubscription =
        _currentSubscription != null && _currentSubscription.isValid();
    if (_currentSubscription != null) {
      _usageFuture = _billingService.fetchUsage();
    }

    _dialog = createProgressDialog(context, "please wait...");

    _purchaseUpdateSubscription = InAppPurchaseConnection
        .instance.purchaseUpdatedStream
        .listen((purchases) async {
      if (!_dialog.isShowing()) {
        await _dialog.show();
      }
      for (final purchase in purchases) {
        _logger.info("Purchase status " + purchase.status.toString());
        if (purchase.status == PurchaseStatus.purchased) {
          try {
            final newSubscription = await _billingService.verifySubscription(
              purchase.productID,
              purchase.verificationData.serverVerificationData,
            );
            await InAppPurchaseConnection.instance.completePurchase(purchase);
            Bus.instance.fire(SubscriptionPurchasedEvent());
            final isUpgrade = _hasActiveSubscription &&
                newSubscription.storage > _currentSubscription.storage;
            final isDowngrade = _hasActiveSubscription &&
                newSubscription.storage < _currentSubscription.storage;
            String text = "your photos and videos will now be backed up";
            if (isUpgrade) {
              text = "your plan was successfully upgraded";
            } else if (isDowngrade) {
              text = "your plan was successfully downgraded";
            }
            showToast(text);
            if (_currentSubscription != null) {
              _currentSubscription = _billingService.getSubscription();
              _hasActiveSubscription = _currentSubscription != null &&
                  _currentSubscription.isValid();
              setState(() {});
            } else {
              Navigator.of(context).popUntil((route) => route.isFirst);
            }
            await _dialog.hide();
          } catch (e) {
            _logger.warning("Could not complete payment ", e);
            await _dialog.hide();
            showErrorDialog(
                context,
                "payment failed",
                "please talk to " +
                    (Platform.isAndroid ? "PlayStore" : "AppStore") +
                    " support if you were charged");
            return;
          }
        } else if (Platform.isIOS && purchase.pendingCompletePurchase) {
          await InAppPurchaseConnection.instance.completePurchase(purchase);
          await _dialog.hide();
        }
      }
    });
    super.initState();
  }

  @override
  void dispose() {
    _purchaseUpdateSubscription.cancel();
    _billingService.setIsOnSubscriptionPage(false);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final appBar = AppBar(
      title: Text("subscription"),
    );
    return Scaffold(
      appBar: appBar,
      body: _getBody(appBar.preferredSize.height),
    );
  }

  Widget _getBody(final appBarSize) {
    return FutureBuilder<List<BillingPlan>>(
      future: _billingService.getBillingPlans(),
      builder: (BuildContext context, AsyncSnapshot snapshot) {
        if (snapshot.hasData) {
          return _buildPlans(context, snapshot.data, appBarSize);
        } else if (snapshot.hasError) {
          return Text("Oops, something went wrong.");
        } else {
          return loadWidget;
        }
      },
    );
  }

  Widget _buildPlans(
      BuildContext context, List<BillingPlan> plans, final appBarSize) {
    final planWidgets = List<Widget>();
    for (final plan in plans) {
      final productID = Platform.isAndroid ? plan.androidID : plan.iosID;
      if (productID == null || productID.isEmpty) {
        continue;
      }
      final isActive =
          _hasActiveSubscription && _currentSubscription.productID == productID;
      planWidgets.add(
        Material(
          child: InkWell(
            onTap: () async {
              if (isActive) {
                return;
              }
              await _dialog.show();
              if (_usageFuture != null) {
                final usage = await _usageFuture;
                if (usage > plan.storage) {
                  await _dialog.hide();
                  showErrorDialog(
                      context, "sorry", "you cannot downgrade to this plan");
                  return;
                }
              }
              final ProductDetailsResponse response =
                  await InAppPurchaseConnection.instance
                      .queryProductDetails([productID].toSet());
              if (response.notFoundIDs.isNotEmpty) {
                await _dialog.hide();
                showGenericErrorDialog(context);
                return;
              }
              final isCrossGradingOnAndroid = Platform.isAndroid &&
                  _hasActiveSubscription &&
                  _currentSubscription.productID != plan.androidID;
              if (isCrossGradingOnAndroid) {
                final existingProductDetailsResponse =
                    await InAppPurchaseConnection.instance.queryProductDetails(
                        [_currentSubscription.productID].toSet());
                if (existingProductDetailsResponse.notFoundIDs.isNotEmpty) {
                  await _dialog.hide();
                  showGenericErrorDialog(context);
                  return;
                }
                final subscriptionChangeParam = ChangeSubscriptionParam(
                  oldPurchaseDetails: PurchaseDetails(
                    purchaseID: null,
                    productID: _currentSubscription.productID,
                    verificationData: null,
                    transactionDate: null,
                  ),
                );
                await InAppPurchaseConnection.instance.buyNonConsumable(
                  purchaseParam: PurchaseParam(
                    productDetails: response.productDetails[0],
                    changeSubscriptionParam: subscriptionChangeParam,
                  ),
                );
              } else {
                await InAppPurchaseConnection.instance.buyNonConsumable(
                  purchaseParam: PurchaseParam(
                    productDetails: response.productDetails[0],
                  ),
                );
              }
            },
            child: SubscriptionPlanWidget(
              plan: plan,
              isActive: isActive,
            ),
          ),
        ),
      );
    }
    final pageSize = MediaQuery.of(context).size.height;
    final notifySize = MediaQuery.of(context).padding.top;
    final widgets = List<Widget>();
    if (_currentSubscription == null) {
      widgets.add(Padding(
        padding: const EdgeInsets.fromLTRB(12, 20, 12, 24),
        child: Text(
          "ente preserves your photos and videos, so they're always available, even if you lose your device",
          style: TextStyle(
            color: Colors.white54,
            height: 1.2,
          ),
        ),
      ));
    } else {
      widgets.add(Container(
        height: 50,
        child: FutureBuilder(
          future: _usageFuture,
          builder: (BuildContext context, AsyncSnapshot snapshot) {
            if (snapshot.hasData) {
              return Padding(
                padding: const EdgeInsets.all(16.0),
                child: Text("current usage is " +
                    convertBytesToGBs(snapshot.data).toString() +
                    " GB"),
              );
            } else if (snapshot.hasError) {
              return Container();
            } else {
              return Padding(
                padding: const EdgeInsets.all(16.0),
                child: loadWidget,
              );
            }
          },
        ),
      ));
    }
    widgets.addAll([
      Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: planWidgets,
      ),
      Padding(padding: EdgeInsets.all(8)),
    ]);

    if (_currentSubscription == null) {
      widgets.addAll([
        Align(
          alignment: Alignment.topLeft,
          child: Padding(
            padding: EdgeInsets.all(12),
            child: Text(
              "we offer a 14 day free trial, you can cancel anytime",
              style: TextStyle(
                color: Colors.white,
                height: 1.2,
              ),
            ),
          ),
        ),
        Expanded(child: Container()),
        Align(
          alignment: Alignment.center,
          child: GestureDetector(
            onTap: () {
              showDialog(
                context: context,
                builder: (builder) {
                  return LearnMoreWidget();
                },
              );
            },
            child: Container(
              padding: EdgeInsets.all(80),
              child: RichText(
                text: TextSpan(
                  text: "learn more",
                  style: TextStyle(
                    color: Colors.blue,
                    fontFamily: 'Ubuntu',
                  ),
                ),
              ),
            ),
          ),
        ),
      ]);
    } else {
      widgets.addAll([
        Expanded(child: Container()),
        Align(
          alignment: Alignment.center,
          child: GestureDetector(
            onTap: () {
              if (Platform.isAndroid) {
                launch(
                    "https://play.google.com/store/account/subscriptions?sku=" +
                        _currentSubscription.productID +
                        "&package=io.ente.photos");
              } else {
                launch("https://apps.apple.com/account/billing");
              }
            },
            child: Container(
              padding: EdgeInsets.all(80),
              child: RichText(
                text: TextSpan(
                  text: "payment details",
                  style: TextStyle(
                    color: Colors.blue,
                    fontFamily: 'Ubuntu',
                  ),
                ),
              ),
            ),
          ),
        ),
      ]);
    }
    return SingleChildScrollView(
      child: Container(
        height: pageSize - (appBarSize + notifySize),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: widgets,
        ),
      ),
    );
  }
}

class LearnMoreWidget extends StatefulWidget {
  const LearnMoreWidget({
    Key key,
  }) : super(key: key);

  @override
  _LearnMoreWidgetState createState() => _LearnMoreWidgetState();
}

class _LearnMoreWidgetState extends State<LearnMoreWidget> {
  int _progress = 0;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.fromLTRB(0, 40, 0, 0),
      child: ClipRRect(
        borderRadius: BorderRadius.only(
          topLeft: Radius.circular(20),
          topRight: Radius.circular(20),
        ),
        child: Column(
          children: [
            Expanded(
              child: InAppWebView(
                initialUrl: 'https://ente.io/faq',
                onProgressChanged: (c, progress) {
                  setState(() {
                    _progress = progress;
                  });
                },
              ),
            ),
            Column(
              children: [
                _progress < 100
                    ? LinearProgressIndicator(
                        value: _progress / 100,
                        minHeight: 2,
                      )
                    : Container(),
                Padding(
                  padding: const EdgeInsets.fromLTRB(16, 0, 16, 0),
                  child: FlatButton(
                    child: Text("close"),
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(12.0),
                    ),
                    color: Colors.grey[850],
                    minWidth: double.infinity,
                    onPressed: () {
                      Navigator.of(context).pop();
                    },
                  ),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

class SubscriptionPlanWidget extends StatelessWidget {
  const SubscriptionPlanWidget({
    Key key,
    @required this.plan,
    this.isActive = false,
  }) : super(key: key);

  final BillingPlan plan;
  final bool isActive;

  @override
  Widget build(BuildContext context) {
    return Container(
      color: Theme.of(context).cardColor,
      child: Column(
        children: [
          Row(
            children: [
              Padding(
                padding: const EdgeInsets.all(10.0),
                child: Card(
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(12.0),
                  ),
                  color: Color(0xDFFFFFFF),
                  child: Container(
                    width: 100,
                    padding: EdgeInsets.fromLTRB(0, 20, 0, 20),
                    child: Column(
                      children: [
                        Text(
                          (plan.storage / (1024 * 1024 * 1024))
                                  .round()
                                  .toString() +
                              " GB",
                          style: TextStyle(
                            fontWeight: FontWeight.bold,
                            fontSize: 16,
                            color: Theme.of(context).cardColor,
                          ),
                        ),
                      ],
                    ),
                  ),
                ),
              ),
              Text(plan.price + " per " + plan.period),
              isActive
                  ? Expanded(
                      child: Icon(
                        Icons.check_circle,
                        color: Colors.cyan[700],
                      ),
                    )
                  : Container(),
            ],
          ),
          Divider(
            height: 1,
          ),
        ],
      ),
    );
  }
}

class SubsriptionSuccessfulDialog extends StatelessWidget {
  const SubsriptionSuccessfulDialog({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Text("success!",
          style: TextStyle(
            fontWeight: FontWeight.bold,
          )),
      content: SingleChildScrollView(
        child: Column(children: [
          Text("your photos and videos will now be backed up"),
          Padding(padding: EdgeInsets.all(6)),
          Text("the first sync might take a while, please bear with us"),
        ]),
      ),
      actions: [
        FlatButton(
          child: Text("ok"),
          onPressed: () {
            Navigator.of(context).pop();
          },
        ),
      ],
    );
  }
}