import 'dart:async';
import 'package:e_scan/components/components.dart';
import 'package:e_scan/pages/operation/reception/reception_scan_page_model.dart';
import 'package:e_scan/themes/app_theme.dart';
import 'package:e_scan/utils/utils.dart';
import 'package:flutter/material.dart';
import 'package:flutter/scheduler.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:mobile_scanner/mobile_scanner.dart';

class ReceptionScanPage extends ConsumerStatefulWidget {
  const ReceptionScanPage({super.key, required this.receptionId});
  final int receptionId;

  @override
  ConsumerState<ConsumerStatefulWidget> createState() =>
      _ReceptionScanPageState();
}

class _ReceptionScanPageState extends ConsumerState<ReceptionScanPage>
    with WidgetsBindingObserver {
  final MobileScannerController mobileScannerController =
      MobileScannerController(
        // required options for the scanner
      );

  StreamSubscription<Object?>? _subscription;
  bool qrcodeFound = false;

  @override
  void initState() {
    super.initState();
    // Start listening to lifecycle changes.
    WidgetsBinding.instance.addObserver(this);

    SchedulerBinding.instance.addPostFrameCallback((_) {
      ref
          .read(receptionScanPageModelProvider.notifier)
          .getReceptionById(id: widget.receptionId);
    });

    // Start listening to the barcode events.
    _subscription = mobileScannerController.barcodes.listen(_handleBarcode);

    // Finally, start the scanner itself.
    unawaited(mobileScannerController.start());
  }

  @override
  void dispose() {
    // Stop listening to lifecycle changes.
    WidgetsBinding.instance.removeObserver(this);
    // Stop listening to the barcode events.
    unawaited(_subscription?.cancel());
    _subscription = null;
    // Dispose the widget itself.
    // Finally, dispose of the controller.
    mobileScannerController.dispose();
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    // If the controller is not ready, do not try to start or stop it.
    // Permission dialogs can trigger lifecycle changes before the controller is ready.
    if (!mobileScannerController.value.hasCameraPermission) {
      return;
    }

    switch (state) {
      case AppLifecycleState.detached:
      case AppLifecycleState.hidden:
      case AppLifecycleState.paused:
        return;
      case AppLifecycleState.resumed:
        // Restart the scanner when the app is resumed.
        // Don't forget to resume listening to the barcode events.
        _subscription = mobileScannerController.barcodes.listen(_handleBarcode);

        unawaited(mobileScannerController.start());
      case AppLifecycleState.inactive:
        // Stop the scanner when the app is paused.
        // Also stop the barcode events subscription.
        unawaited(_subscription?.cancel());
        _subscription = null;
        unawaited(mobileScannerController.stop());
    }
  }

  Future<void> _handleBarcode(BarcodeCapture barcodeCapture) async {
    if (qrcodeFound) return;
    if (barcodeCapture.barcodes.isNotEmpty) {
      qrcodeFound = true;
      mobileScannerController.stop();
      final code = barcodeCapture.barcodes.first;
      final qrcodeValue = code.displayValue;
      debugPrint("Code détecté : ${code.displayValue}");
      final model = ref.read(receptionScanPageModelProvider.notifier);

      if (qrcodeValue == null) {
        debugPrint("Produit non attendu dans cette réception");
        Toast.showError('Produit non attendu dans cette réception');
        return;
      }
      // find product in local database
      final product = model.getProduct(
        receptionId: widget.receptionId,
        barcode: qrcodeValue,
      );
      if (product != null) {
        model.incrementMoveLineQuantity(
          barcode: qrcodeValue,
          receptionId: widget.receptionId,
          onError: () {
            Toast.showError('Aucun produit trouvé.');
          },
        );
        //show dialog
        await showDialog(
          barrierDismissible: false,
          context: context,
          builder: (dialogContext) {
            return Dialog(
              elevation: 0,
              insetPadding: EdgeInsets.zero,
              backgroundColor: Colors.transparent,
              alignment: AlignmentDirectional(
                0.0,
                0.0,
              ).resolve(Directionality.of(context)),
              child: GestureDetector(
                onTap: () {
                  FocusScope.of(dialogContext).unfocus();
                  FocusManager.instance.primaryFocus?.unfocus();
                },
                child: SizedBox(
                  width: MediaQuery.sizeOf(context).width * 0.9,
                  child: ProductScannedComponent(
                    productStruct: product,
                    onRescan: () async {
                      Navigator.of(context).pop();
                      qrcodeFound = false;
                      mobileScannerController.start();
                    },
                    onDetails: () {
                      unawaited(_subscription?.cancel());
                      _subscription = null;
                      unawaited(mobileScannerController.stop());
                      Navigator.of(context).pop();
                      Navigator.of(context).pop();
                    },
                  ),
                ),
              ),
            );
          },
        );
      } else {
        Toast.showError('Produit non attendu dans cette réception');
        debugPrint('Produit non attendu dans cette réception');
      }
    }
  }

  Future<void> _fakeBarcode() async {
    final qrcodeValue = "AIRF0001";
    qrcodeFound = true;
    final model = ref.read(receptionScanPageModelProvider.notifier);
    mobileScannerController.stop();
    // find product in local database
    final product = model.getProduct(
      receptionId: widget.receptionId,
      barcode: qrcodeValue,
    );
    if (product != null) {
      model.incrementMoveLineQuantity(
        barcode: qrcodeValue,
        receptionId: widget.receptionId,
        onError: () {
          Toast.showError('Aucun produit trouvé.');
        },
      );
      //show dialog
      await showDialog(
        barrierDismissible: false,
        context: context,
        builder: (dialogContext) {
          return Dialog(
            elevation: 0,
            insetPadding: EdgeInsets.zero,
            backgroundColor: Colors.transparent,
            alignment: AlignmentDirectional(
              0.0,
              0.0,
            ).resolve(Directionality.of(context)),
            child: GestureDetector(
              onTap: () {
                FocusScope.of(dialogContext).unfocus();
                FocusManager.instance.primaryFocus?.unfocus();
              },
              child: SizedBox(
                width: MediaQuery.sizeOf(context).width * 0.9,
                child: ProductScannedComponent(
                  productStruct: product,
                  onRescan: () async {
                    qrcodeFound = false;
                    mobileScannerController.start();
                    Navigator.of(context).pop();
                  },
                  onDetails: () {
                    unawaited(_subscription?.cancel());
                    _subscription = null;
                    unawaited(mobileScannerController.stop());
                    Navigator.of(context).pop();
                    Navigator.of(context).pop();
                  },
                ),
              ),
            ),
          );
        },
      );
    } else {
      Toast.showError('Aucun produit trouvé.');
      debugPrint('Aucun produit trouvé.');
    }
  }

  @override
  Widget build(BuildContext context) {
    final state = ref.watch(receptionScanPageModelProvider);
    final reception = state.reception;
    return Scaffold(
      backgroundColor: AppTheme.of(context).primaryBackground,
      appBar: AppBar(
        backgroundColor: AppTheme.of(context).primaryBackground,
        automaticallyImplyLeading: false,
        leading: IconButton(
          icon: Icon(
            Icons.arrow_back_ios,
            color: AppTheme.of(context).primaryText,
            size: 24.0,
          ),
          onPressed: () async {
            Navigator.of(context).pop();
          },
        ),
        title: Text(
          'Réception ${reception?.name}',
          style: AppTheme.of(context).titleLarge,
        ),
        actions: [
          Padding(
            padding: EdgeInsetsDirectional.fromSTEB(8.0, 0.0, 8.0, 0.0),
            child: IconButton(
              icon: Icon(Icons.help_outline, color: Colors.white, size: 24.0),
              onPressed: () {
                debugPrint('IconButton pressed ...');
              },
            ),
          ),
        ],
        centerTitle: true,
        elevation: 0.0,
      ),
      body: state.loading
          ? Center(child: LoadingProgressComponent())
          : SizedBox(
              width: double.infinity,
              height: double.infinity,
              child: Stack(
                children: [
                  SizedBox(
                    width: double.infinity,
                    height: double.infinity,
                    child: MobileScanner(
                      controller: mobileScannerController,
                      onDetectError: (error, stackTrace) {
                        debugPrint("===========> $error");
                      },
                      errorBuilder: (c, p2) {
                        return Center(child: Icon(Icons.error));
                      },
                    ),
                  ),
                  Container(
                    width: double.infinity,
                    height: double.infinity,
                    decoration: BoxDecoration(
                      gradient: LinearGradient(
                        colors: [
                          AppTheme.of(context).primaryBackground,
                          Colors.transparent,
                          AppTheme.of(context).primaryBackground,
                        ],
                        stops: [0.0, 0.5, 1.0],
                        begin: AlignmentDirectional(0.0, -1.0),
                        end: AlignmentDirectional(0, 1.0),
                      ),
                    ),
                    child: Padding(
                      padding: EdgeInsets.all(16.0),
                      child: Column(
                        mainAxisSize: MainAxisSize.max,
                        mainAxisAlignment: MainAxisAlignment.spaceBetween,
                        children: [
                          _InfoTextScan(),
                          _ZoneScanBox(
                            onTap: () {
                              // _fakeBarcode();
                              qrcodeFound = false;
                              mobileScannerController.start();
                            },
                          ),
                          FlashButtonComponent(
                            mobileScannerController: mobileScannerController,
                          ),
                        ],
                      ),
                    ),
                  ),
                ],
              ),
            ),
    );
  }
}

class _ZoneScanBox extends StatelessWidget {
  const _ZoneScanBox({this.onTap});
  final VoidCallback? onTap;

  @override
  Widget build(BuildContext context) {
    return Align(
      alignment: AlignmentDirectional(0.0, 0.0),
      child: Container(
        width: 280.0,
        height: 280.0,
        decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(16.0),
          border: Border.all(color: Colors.white, width: 3.0),
        ),
        child: GestureDetector(
          onTap: onTap,
          child: Container(
            width: 260.0,
            height: 260.0,
            decoration: BoxDecoration(
              color: Color(0x33FFFFFF),
              borderRadius: BorderRadius.circular(12.0),
            ),
            child: Padding(
              padding: EdgeInsets.all(16.0),
              child: Column(
                mainAxisSize: MainAxisSize.max,
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Icon(
                    Icons.qr_code_scanner,
                    color: Colors.white.withValues(alpha: .5),
                    size: 64.0,
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }
}

class _InfoTextScan extends StatelessWidget {
  const _InfoTextScan();

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: EdgeInsetsDirectional.fromSTEB(24.0, 40.0, 24.0, 0.0),
      child: Column(
        mainAxisSize: MainAxisSize.max,
        crossAxisAlignment: CrossAxisAlignment.center,
        children: [
          Text(
            'Scanner le code',
            textAlign: TextAlign.center,
            style: TextStyle(color: AppTheme.of(context).primaryText),
          ),
          Padding(
            padding: EdgeInsetsDirectional.fromSTEB(0.0, 8.0, 0.0, 0.0),
            child: Text(
              'Positionnez le code-barres ou QR code dans le cadre',
              textAlign: TextAlign.center,
              style: TextStyle(color: AppTheme.of(context).primaryText),
            ),
          ),
        ],
      ),
    );
  }
}