cb_prestige_qr/lib/features/scan/presentation/viewmodels/scan_controller.dart

import 'package:cb_prestige_qr/features/scan/presentation/providers/scan_providers.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';

final scanControllerProvider = NotifierProvider<ScanController, ScanState>(
  ScanController.new,
);

class ScanState {
  const ScanState({
    this.isScanning = true,
    this.isProcessing = false,
    this.isSubmitting = false,
    this.scannedValue,
    this.errorMessage,
  });

  final bool isScanning;
  final bool isProcessing;
  final bool isSubmitting;
  final String? scannedValue;
  final String? errorMessage;

  static const _sentinel = Object();

  ScanState copyWith({
    bool? isScanning,
    bool? isProcessing,
    bool? isSubmitting,
    Object? scannedValue = _sentinel,
    Object? errorMessage = _sentinel,
  }) {
    return ScanState(
      isScanning: isScanning ?? this.isScanning,
      isProcessing: isProcessing ?? this.isProcessing,
      isSubmitting: isSubmitting ?? this.isSubmitting,
      scannedValue: identical(scannedValue, _sentinel)
          ? this.scannedValue
          : scannedValue as String?,
      errorMessage: identical(errorMessage, _sentinel)
          ? this.errorMessage
          : errorMessage as String?,
    );
  }
}

class ScanController extends Notifier<ScanState> {
  @override
  ScanState build() => const ScanState();

  Future<void> onBarcodeDetected(String value) async {
    if (!state.isScanning || state.isProcessing) return;
    state = state.copyWith(
      isScanning: false,
      isProcessing: true,
      errorMessage: null,
    );

    try {
      final result = await ref.read(processScanUseCaseProvider)(value);
      state = state.copyWith(
        isProcessing: false,
        scannedValue: result.rawValue,
      );
    } catch (error) {
      state = state.copyWith(
        isProcessing: false,
        isScanning: true,
        scannedValue: null,
        errorMessage: error.toString(),
      );
    }
  }

  Future<void> submitScannedValue(String value) async {
    if (state.isSubmitting) return;
    state = state.copyWith(isSubmitting: true, errorMessage: null);

    try {
      await ref.read(scanRepositoryProvider).submitScan(value);
      state = state.copyWith(
        isSubmitting: false,
        scannedValue: null,
        errorMessage: null,
      );
    } catch (error) {
      state = state.copyWith(
        isSubmitting: false,
        errorMessage: error.toString(),
      );
      rethrow;
    }
  }

  void resumeScanning() {
    state = const ScanState(
      isScanning: true,
      isProcessing: false,
      isSubmitting: false,
      scannedValue: null,
      errorMessage: null,
    );
  }
}