import 'package:eatvio_app/core/locator_service.dart';
import 'package:eatvio_app/core/utils/toasts.dart';
import 'package:eatvio_app/features/payment/models/promo_apply_response.dart';
import 'package:eatvio_app/features/payment/models/promo_code_model.dart';
import 'package:eatvio_app/features/payment/models/promo_validate_response.dart';
import 'package:eatvio_app/features/payment/presentation/widgets/promo_code_gate_bottom_sheet.dart';
import 'package:eatvio_app/features/payment/presentation/widgets/promo_code_modal.dart';
import 'package:eatvio_app/features/payment/presentation/widgets/sbp_banks_bottom_sheet.dart';
import 'package:eatvio_app/features/payment/repositories/payment_repository.dart';
import 'package:flutter/material.dart';

/// Оркестрирует флоу оплаты консультации:
/// applied rehydrate → (или гейт → форма) → apply при необходимости → SbpBanks.
Future<void> showConsultationPaymentFlow(
  BuildContext context, {
  required int planId,
  Future<bool?> Function(BuildContext)? showGate,
  Future<PromoCodeResult?> Function(
    BuildContext, {
    Future<PromoValidation> Function(String)? onValidate,
    Future<bool> Function()? onRemove,
    PromoCodeModel? initialPromo,
  })? showForm,
  Future<void> Function(BuildContext, {required int planId})? showSbp,
  Future<PromoValidateResponse> Function({
    required int planId,
    required String promoCode,
  })? validatePromo,
  Future<PromoApplyResponse> Function({
    required int planId,
    required String promoCode,
  })? applyPromo,
  Future<PromoCodeModel?> Function(int planId)? listApplied,
  Future<bool> Function(int planId)? removePromo,
}) async {
  final gate = showGate ?? _showGate;
  final form = showForm ?? _showForm;
  final sbp = showSbp ?? _showSbp;
  final validate = validatePromo ?? _defaultValidatePromo;
  final apply = applyPromo ?? _defaultApplyPromo;
  final findApplied = listApplied ?? _defaultFindApplied;
  final remove = removePromo ?? _defaultRemovePromo;

  final existing = await findApplied(planId);
  if (!context.mounted) return;

  if (existing != null) {
    final formResult = await form(
      context,
      initialPromo: existing,
      onRemove: () => remove(planId),
      onValidate: (code) => _mapValidateResponse(
        validate(planId: planId, promoCode: code),
      ),
    );
    if (formResult == null || !context.mounted) return;

    if (formResult.hasPromoCode && !formResult.alreadyApplied) {
      final applied = await _tryApplyPromo(
        apply: apply,
        planId: planId,
        promoCode: formResult.code!,
      );
      if (!applied || !context.mounted) return;
    }

    if (!context.mounted) return;
    await sbp(context, planId: planId);
    return;
  }

  final gateChoice = await gate(context);
  if (gateChoice == null || !context.mounted) return;

  if (gateChoice) {
    final formResult = await form(
      context,
      onValidate: (code) => _mapValidateResponse(
        validate(planId: planId, promoCode: code),
      ),
    );
    if (formResult == null || !context.mounted) return;

    if (formResult.hasPromoCode && !formResult.alreadyApplied) {
      final applied = await _tryApplyPromo(
        apply: apply,
        planId: planId,
        promoCode: formResult.code!,
      );
      if (!applied || !context.mounted) return;
    }
  }

  if (!context.mounted) return;
  await sbp(context, planId: planId);
}

Future<bool?> _showGate(BuildContext context) {
  return showPromoCodeGateBottomSheet(context);
}

Future<PromoCodeResult?> _showForm(
  BuildContext context, {
  Future<PromoValidation> Function(String)? onValidate,
  Future<bool> Function()? onRemove,
  PromoCodeModel? initialPromo,
}) {
  return ItvioPromoCodeModal.show(
    context,
    onValidate: onValidate,
    onRemove: onRemove,
    initialPromo: initialPromo,
  );
}

Future<void> _showSbp(BuildContext context, {required int planId}) {
  return showSbpBanksBottomSheet(context, planId: planId);
}

Future<PromoValidateResponse> _defaultValidatePromo({
  required int planId,
  required String promoCode,
}) {
  return sl<PaymentRepository>().validatePromoCode(
    planId: planId,
    promoCode: promoCode,
  );
}

Future<PromoApplyResponse> _defaultApplyPromo({
  required int planId,
  required String promoCode,
}) {
  return sl<PaymentRepository>().applyPromoCode(
    planId: planId,
    promoCode: promoCode,
  );
}

Future<PromoCodeModel?> _defaultFindApplied(int planId) {
  return sl<PaymentRepository>().findAppliedPromoForPlan(planId);
}

Future<bool> _defaultRemovePromo(int planId) async {
  try {
    final response = await sl<PaymentRepository>().removePromoCode(planId: planId);
    if (response.success) return true;
    showErrorToast(response.error ?? 'Не удалось убрать промокод.');
    return false;
  } catch (_) {
    showErrorToast('Не удалось убрать промокод. Попробуйте позже');
    return false;
  }
}

Future<PromoValidation> _mapValidateResponse(
  Future<PromoValidateResponse> request,
) async {
  try {
    final response = await request;
    if (!response.valid) {
      return PromoValidation.failure(
        response.error ?? 'Промокод невалиден.',
      );
    }
    return PromoValidation.success(
      discountPercent: response.discountPercent,
      discountAmountRub: response.discountAmountRub,
      originalAmountRub: response.originalAmountRub,
      finalAmountRub: response.finalAmountRub,
    );
  } catch (_) {
    return const PromoValidation.failure(
      'Не удалось проверить промокод. Попробуйте позже',
    );
  }
}

Future<bool> _tryApplyPromo({
  required Future<PromoApplyResponse> Function({
    required int planId,
    required String promoCode,
  }) apply,
  required int planId,
  required String promoCode,
}) async {
  try {
    final response = await apply(planId: planId, promoCode: promoCode);
    if (response.success) return true;

    showErrorToast(response.error ?? 'Не удалось применить промокод.');
    return false;
  } catch (_) {
    showErrorToast('Не удалось применить промокод. Попробуйте позже');
    return false;
  }
}