import 'package:pshared/controllers/payment/source.dart';
import 'package:pshared/models/payment/asset.dart';
import 'package:pshared/models/payment/chain_network.dart';
import 'package:pshared/models/payment/customer.dart';
import 'package:pshared/models/payment/currency_pair.dart';
import 'package:pshared/models/payment/fees/treatment.dart';
import 'package:pshared/models/payment/fx/intent.dart';
import 'package:pshared/models/payment/fx/side.dart';
import 'package:pshared/models/payment/kind.dart';
import 'package:pshared/models/payment/methods/card.dart';
import 'package:pshared/models/payment/methods/crypto_address.dart';
import 'package:pshared/models/payment/methods/data.dart';
import 'package:pshared/models/payment/methods/iban.dart';
import 'package:pshared/models/payment/methods/ledger.dart';
import 'package:pshared/models/payment/methods/managed_wallet.dart';
import 'package:pshared/models/payment/methods/russian_bank.dart';
import 'package:pshared/models/payment/methods/type.dart';
import 'package:pshared/models/money.dart';
import 'package:pshared/models/payment/settlement_mode.dart';
import 'package:pshared/models/payment/intent.dart';
import 'package:pshared/models/recipient/recipient.dart';
import 'package:pshared/provider/payment/amount.dart';
import 'package:pshared/provider/payment/flow.dart';
import 'package:pshared/provider/recipient/provider.dart';
import 'package:pshared/utils/payment/fx_helpers.dart';


class QuotationIntentBuilder {
  static const String _settlementCurrency = 'RUB';

  PaymentIntent? build({
    required PaymentAmountProvider payment,
    required PaymentSourceController source,
    required PaymentFlowProvider flow,
    required RecipientsProvider recipients,
  }) {
    final sourceMethod = _resolveSourceMethod(source);
    final sourceCurrency = source.selectedCurrencyCode;
    final paymentData = flow.selectedPaymentData;
    final selectedMethod = flow.selectedMethod;
    if (sourceMethod == null || sourceCurrency == null || paymentData == null) {
      return null;
    }

    final customer = _buildCustomer(
      recipient: recipients.currentObject,
      method: selectedMethod,
      data: paymentData,
    );
    final amountCurrency = payment.settlementMode == SettlementMode.fixReceived
        ? _settlementCurrency
        : sourceCurrency;
    final amount = Money(
      amount: payment.amount.toString(),
      currency: amountCurrency,
    );
    final isLedgerSource = source.selectedLedgerAccount != null;
    final isCryptoToCrypto =
        paymentData is CryptoAddressPaymentMethod &&
        (paymentData.asset?.tokenSymbol ?? '').trim().toUpperCase() ==
            amount.currency;
    final fxIntent = _buildFxIntent(
      sourceCurrency: sourceCurrency,
      settlementMode: payment.settlementMode,
      isLedgerSource: isLedgerSource,
      enabled: !isCryptoToCrypto,
    );
    return PaymentIntent(
      kind: PaymentKind.payout,
      amount: amount,
      destination: paymentData,
      source: sourceMethod,
      fx: fxIntent,
      feeTreatment: payment.payerCoversFee
          ? FeeTreatment.addToSource
          : FeeTreatment.deductFromDestination,
      settlementMode: payment.settlementMode,
      customer: customer,
    );
  }

  FxIntent? _buildFxIntent({
    required String sourceCurrency,
    required SettlementMode settlementMode,
    required bool isLedgerSource,
    required bool enabled,
  }) {
    if (!enabled) return null;

    // Ledger sources in fix_received mode need explicit reverse side.
    // BFF maps only settlement currency + fx side, then quotation derives pair.
    // For ledger this preserves source debit in ledger currency (e.g. USDT).
    if (isLedgerSource && settlementMode == SettlementMode.fixReceived) {
      final base = sourceCurrency.trim();
      final quote = _settlementCurrency;
      if (base.isEmpty || base.toUpperCase() == quote.toUpperCase()) {
        return null;
      }
      return FxIntent(
        pair: CurrencyPair(base: base, quote: quote),
        side: FxSide.sellBaseBuyQuote,
      );
    }

    return FxIntentHelper.buildSellBaseBuyQuote(
      baseCurrency: sourceCurrency,
      quoteCurrency: _settlementCurrency, // TODO: exentd target currencies
      enabled: true,
    );
  }

  PaymentMethodData? _resolveSourceMethod(PaymentSourceController source) {
    final wallet = source.selectedWallet;
    if (wallet != null) {
      return ManagedWalletPaymentMethod(
        managedWalletRef: wallet.id,
        asset: PaymentAsset(
          tokenSymbol: wallet.tokenSymbol ?? '',
          chain: wallet.network ?? ChainNetwork.unspecified,
        ),
      );
    }

    final ledger = source.selectedLedgerAccount;
    if (ledger != null) {
      return LedgerPaymentMethod(ledgerAccountRef: ledger.ledgerAccountRef);
    }

    return null;
  }

  Customer? _buildCustomer({
    required Recipient? recipient,
    required PaymentMethod? method,
    required PaymentMethodData? data,
  }) {
    final id = recipient?.id ?? method?.recipientRef;
    if (id == null || id.isEmpty) return null;

    final name = _resolveCustomerName(
      method: method,
      data: data,
      recipient: recipient,
    );
    final parts = name == null || name.trim().isEmpty
        ? const <String>[]
        : name.trim().split(RegExp(r'\s+'));
    final firstName = parts.isNotEmpty ? parts.first : null;
    final lastName = parts.length >= 2 ? parts.last : null;
    final middleName = parts.length > 2
        ? parts.sublist(1, parts.length - 1).join(' ')
        : null;

    return Customer(
      id: id,
      firstName: firstName,
      middleName: middleName,
      lastName: lastName,
      country: _resolveCustomerCountry(method: method, data: data),
    );
  }

  String? _resolveCustomerName({
    required PaymentMethod? method,
    required PaymentMethodData? data,
    required Recipient? recipient,
  }) {
    final card = method?.cardData ?? (data is CardPaymentMethod ? data : null);
    if (card != null) {
      final fullName = '${card.firstName} ${card.lastName}'.trim();
      if (fullName.isNotEmpty) return fullName;
    }

    final iban = method?.ibanData ?? (data is IbanPaymentMethod ? data : null);
    if (iban != null && iban.accountHolder.trim().isNotEmpty) {
      return iban.accountHolder.trim();
    }

    final bank =
        method?.bankAccountData ??
        (data is RussianBankAccountPaymentMethod ? data : null);
    if (bank != null && bank.recipientName.trim().isNotEmpty) {
      return bank.recipientName.trim();
    }

    final recipientName = recipient?.name.trim();
    return recipientName?.isNotEmpty == true ? recipientName : null;
  }

  String? _resolveCustomerCountry({
    required PaymentMethod? method,
    required PaymentMethodData? data,
  }) {
    final card = method?.cardData ?? (data is CardPaymentMethod ? data : null);
    return card?.country;
  }
}