hash-wallet/lib/view_model/anon_invoice_page_view_model.dart

import 'package:hash_wallet/anonpay/anonpay_api.dart';
import 'package:hash_wallet/anonpay/anonpay_invoice_info.dart';
import 'package:hash_wallet/anonpay/anonpay_request.dart';
import 'package:hash_wallet/core/execution_state.dart';
import 'package:hash_wallet/entities/fiat_currency.dart';
import 'package:hash_wallet/entities/preferences_key.dart';
import 'package:hash_wallet/utils/qr_util.dart';
import 'package:cw_core/receive_page_option.dart';
import 'package:hash_wallet/store/settings_store.dart';
import 'package:cw_core/crypto_currency.dart';
import 'package:cw_core/currency.dart';
import 'package:cw_core/wallet_base.dart';
import 'package:hive/hive.dart';
import 'package:mobx/mobx.dart';
import 'package:shared_preferences/shared_preferences.dart';

part 'anon_invoice_page_view_model.g.dart';

class AnonInvoicePageViewModel = AnonInvoicePageViewModelBase with _$AnonInvoicePageViewModel;

abstract class AnonInvoicePageViewModelBase with Store {
  AnonInvoicePageViewModelBase(
    this.anonPayApi,
    this.address,
    this.settingsStore,
    this._wallet,
    this._anonpayInvoiceInfoSource,
    this.sharedPreferences,
    this.pageOption,
  )   : receipientEmail = '',
        receipientName = '',
        description = '',
        amount = '',
        state = InitialExecutionState(),
        selectedCurrency = _wallet.currency,
        cryptoCurrency = _wallet.currency {
    _getPreviousDonationLink();
    _fetchLimits();
  }

  List<Currency> get currencies => [_wallet.currency, ...FiatCurrency.all];
  final AnonPayApi anonPayApi;
  final String address;
  final SettingsStore settingsStore;
  final WalletBase _wallet;
  final Box<AnonpayInvoiceInfo> _anonpayInvoiceInfoSource;
  final SharedPreferences sharedPreferences;
  final ReceivePageOption pageOption;

  @observable
  Currency selectedCurrency;

  CryptoCurrency cryptoCurrency;

  @observable
  String receipientEmail;

  @observable
  String receipientName;

  @observable
  String description;

  @observable
  String amount;

  @observable
  ExecutionState state;

  @computed
  int get selectedCurrencyIndex => currencies.indexOf(selectedCurrency);

  @observable
  double? minimum;

  @observable
  double? maximum;

  @action
  void selectCurrency(Currency currency) {
    selectedCurrency = currency;
    maximum = minimum = null;
    if (currency is CryptoCurrency) {
      cryptoCurrency = currency;
    } else {
      cryptoCurrency = _wallet.currency;
    }

    _fetchLimits();
  }

  @action
  Future<void> createInvoice() async {
    state = IsExecutingState();
    if (amount.isNotEmpty) {
      final amountInCrypto = double.tryParse(amount);
      if (amountInCrypto == null) {
        state = FailureState('Amount is invalid');
        return;
      }
      if (minimum != null && amountInCrypto < minimum!) {
        state = FailureState('Amount is too small');
        return;
      }
      if (maximum != null && amountInCrypto > maximum!) {
        state = FailureState('Amount is too big');
        return;
      }
    }
    try {
      final result = await anonPayApi.createInvoice(AnonPayRequest(
        cryptoCurrency: cryptoCurrency,
        address: address,
        amount: amount.isEmpty ? null : amount,
        description: description,
        email: receipientEmail,
        name: receipientName,
        fiatEquivalent:
            selectedCurrency is FiatCurrency ? (selectedCurrency as FiatCurrency).raw : null,
      ));

      _anonpayInvoiceInfoSource.add(result);

      state = ExecutedSuccessfullyState(payload: result);
    } catch (e) {
      state = FailureState(e.toString());
    }
  }

  @action
  void setRequestParams({
    required String inputAmount,
    required String inputName,
    required String inputEmail,
    required String inputDescription,
  }) {
    receipientName = inputName;
    receipientEmail = inputEmail;
    description = inputDescription;
    amount = inputAmount;
  }

  @action
  Future<void> generateDonationLink() async {
    state = IsExecutingState();

    final result = await anonPayApi.generateDonationLink(AnonPayRequest(
      cryptoCurrency: cryptoCurrency,
      address: address,
      description: description,
      email: receipientEmail,
      name: receipientName,
    ));

    await sharedPreferences.setString(PreferencesKey.clearnetDonationLink, result.clearnetUrl);
    await sharedPreferences.setString(PreferencesKey.onionDonationLink, result.onionUrl);
    await sharedPreferences.setString(PreferencesKey.donationLinkWalletName, _wallet.name);

    state = ExecutedSuccessfullyState(payload: result);
  }

  Future<void> _fetchLimits() async {
    try {
      final limit = await anonPayApi.fetchLimits(
        cryptoCurrency: cryptoCurrency,
        fiatCurrency: selectedCurrency is FiatCurrency ? selectedCurrency as FiatCurrency : null,
      );
      minimum = limit.min;
      maximum = limit.max != null ? limit.max! / 4 : null;
    } catch (e) {
      state = FailureState(e.toString());
    }
  }

  @computed
  String get currentWalletName => _wallet.name;

  @computed
  String get qrImage => getQrImage(_wallet.type);

  @action
  void reset() {
    selectedCurrency = _wallet.currency;
    cryptoCurrency = _wallet.currency;
    receipientEmail = '';
    receipientName = '';
    description = '';
    amount = '';
    _fetchLimits();
  }

  Future<void> _getPreviousDonationLink() async {
    if (pageOption == ReceivePageOption.anonPayDonationLink) {
      final donationLink = sharedPreferences.getString(PreferencesKey.clearnetDonationLink);
      final donationLinkWalletName =
          sharedPreferences.getString(PreferencesKey.donationLinkWalletName);

      if (donationLink != null && currentWalletName == donationLinkWalletName) {
        final url = Uri.parse(donationLink);
        url.queryParameters.forEach((key, value) {
          if (key == 'name') receipientName = value;
          if (key == 'email') receipientEmail = value;
          if (key == 'description') description = Uri.decodeComponent(value);
        });
      }
    }
  }
}