import 'package:flutter/material.dart';
import 'package:flutter_svg/svg.dart';
import 'package:go_router/go_router.dart';
import 'package:mobile_scanner/mobile_scanner.dart';
import 'package:seshat/domain/models/book.dart';
import 'package:seshat/routing/routes.dart';
import 'package:seshat/ui/add_page/view_model/add_view_model.dart';
import 'package:seshat/ui/add_page/widgets/form_popup.dart';
import 'package:seshat/ui/add_page/widgets/owner_popup.dart';
import 'package:seshat/ui/add_page/widgets/confirmation_popup.dart';
import 'package:seshat/ui/core/ui/navigation_bar.dart';
import 'package:seshat/ui/core/ui/await_loading.dart';
import 'package:seshat/utils/result.dart';

class AddPage extends StatefulWidget {
  const AddPage({super.key, required this.viewModel});

  final AddViewModel viewModel;

  @override
  State<AddPage> createState() => _AddPageState();
}

class _AddPageState extends State<AddPage> {
  final MobileScannerController scannerController = MobileScannerController(
    formats: [BarcodeFormat.ean13],
    detectionTimeoutMs: 1000,
  );

  @override
  void dispose() {
    scannerController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    return Scaffold(
      bottomNavigationBar: AppNavigationBar(startIndex: 1),
      body: ListenableBuilder(
        listenable: widget.viewModel,
        builder: (context, child) => switch (widget.viewModel.isLoaded) {
          false => AwaitLoading(),
          true => switch (widget.viewModel.ongoingBal) {
            null => Center(
              child: SizedBox(
                width: 300,
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  crossAxisAlignment: CrossAxisAlignment.center,
                  children: [
                    Text(
                      "Aucune bal n'est active.",
                      style: TextStyle(fontSize: 25),
                      textAlign: TextAlign.center,
                    ),
                    SizedBox(height: 15),
                    Text(
                      "Vous devez créer puis activer une BAL pour pouvoir scanner des livres.",
                      textAlign: TextAlign.center,
                    ),
                    SizedBox(height: 30),
                    ElevatedButton(
                      onPressed: () {
                        context.go(Routes.home);
                      },
                      child: Text("Gérer les BALs"),
                    ),
                  ],
                ),
              ),
            ),
            _ => Stack(
              children: [
                ColoredBox(color: Colors.black),
                MobileScanner(
                  controller: scannerController,
                  onDetect: (barcodes) async {
                    if (barcodes.barcodes.isEmpty) {
                      return;
                    }

                    if (widget.viewModel.currentOwner == null) {
                      _showMissingOwnerSnackBar(
                        context,
                        scannerController,
                        widget.viewModel,
                      );
                      return;
                    }

                    _scanEan(
                      context,
                      widget.viewModel,
                      barcodes.barcodes.first.rawValue!,
                      scannerController,
                    );
                  },
                ),

                Center(
                  child: SvgPicture.asset(
                    'assets/scan-overlay.svg',
                    height: (MediaQuery.sizeOf(context).height / 5) * 2,
                  ),
                ),

                SafeArea(
                  child: SingleChildScrollView(
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.center,
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        SizedBox(height: 5),
                        Center(
                          child: Card(
                            margin: EdgeInsets.symmetric(horizontal: 50),
                            child: Column(
                              mainAxisSize: MainAxisSize.min,
                              children: [
                                ListTile(
                                  leading: Icon(Icons.person),
                                  title: TextButton(
                                    child: Text(
                                      (widget.viewModel.currentOwner == null)
                                          ? "Aucun"
                                          : "${widget.viewModel.currentOwner!.firstName} ${widget.viewModel.currentOwner!.lastName}",
                                    ),
                                    onPressed: () => _ownerDialogBuilder(
                                      context,
                                      scannerController,
                                      widget.viewModel,
                                    ),
                                  ),
                                ),
                                ListTile(
                                  leading: Icon(Icons.attach_money),
                                  title: TextButton(
                                    child: Text(
                                      (widget.viewModel.askPrice)
                                          ? "Demander à chaque fois"
                                          : "Prix libre toujours",
                                    ),
                                    onPressed: () {
                                      setState(() {
                                        widget.viewModel.askPrice =
                                            !widget.viewModel.askPrice;
                                      });
                                    },
                                  ),
                                ),
                              ],
                            ),
                          ),
                        ),
                      ],
                    ),
                  ),
                ),

                SafeArea(
                  child: Column(
                    mainAxisAlignment: MainAxisAlignment.end,
                    children: [
                      Center(
                        child: TextButton(
                          style: ButtonStyle(
                            backgroundColor: WidgetStatePropertyAll(
                              theme.cardColor,
                            ),
                          ),
                          onPressed: () {
                            if (widget.viewModel.currentOwner == null) {
                              _showMissingOwnerSnackBar(
                                context,
                                scannerController,
                                widget.viewModel,
                              );
                              return;
                            }

                            _formDialogBuilder(
                              context,
                              scannerController,
                              widget.viewModel,
                            );
                          },
                          child: Text("Enregistrer manuellement"),
                        ),
                      ),
                      SizedBox(height: 5),
                    ],
                  ),
                ),
              ],
            ),
          },
        },
      ),
    );
    // },
    // );
  }
}

void _scanEan(
  BuildContext context,
  AddViewModel viewModel,
  String ean,
  MobileScannerController scannerController, {
  Function(BuildContext)? leaveLastPopup,
}) async {
  Result<Book> result = await viewModel.scanBook(ean);

  if (context.mounted) {
    if (leaveLastPopup != null) {
      leaveLastPopup(context);
    }
    switch (result) {
      case Ok():
        await _confirmationDialogBuilder(
          context,
          scannerController,
          viewModel,
          result.value,
        );
        break;
      case Error():
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(
            content: Text("Erreur : ${result.error}"),
            behavior: SnackBarBehavior.floating,
          ),
        );
        break;
    }
  }
}

void _showMissingOwnerSnackBar(
  BuildContext context,
  MobileScannerController scannerController,
  AddViewModel viewModel,
) {
  ScaffoldMessenger.of(context).showSnackBar(
    SnackBar(
      content: Text("Attention : vous devez choisir un·e propriétaire"),
      duration: Duration(seconds: 4),
      action: SnackBarAction(
        label: "Choisir",
        onPressed: () =>
            _ownerDialogBuilder(context, scannerController, viewModel),
      ),
      behavior: SnackBarBehavior.floating,
    ),
  );
}

Future<void> _confirmationDialogBuilder(
  BuildContext context,
  MobileScannerController scannerController,
  AddViewModel viewModel,
  Book book,
) {
  scannerController.stop();

  // Utility function to pass to downwards widgets
  void exitPopup(BuildContext localContext) {
    Navigator.of(localContext).pop();
    scannerController.start();
  }

  return showDialog(
    context: context,
    barrierDismissible: false,
    builder: (context) => ConfirmationPopup(
      exitPopup: exitPopup,
      viewModel: viewModel,
      book: book,
    ),
  );
}

Future<void> _formDialogBuilder(
  BuildContext context,
  MobileScannerController controller,
  AddViewModel viewModel,
) {
  controller.stop();

  // Utility function to pass to downwards widgets
  void exitPopup(BuildContext localContext) {
    Navigator.of(localContext).pop();
    controller.start();
  }

  return showDialog(
    context: context,
    barrierDismissible: false,
    builder: (context) => FormPopup(
      viewModel: viewModel,
      exitPopup: exitPopup,
      scannerController: controller,
      scanEan: _scanEan,
    ),
  );
}

Future<void> _ownerDialogBuilder(
  BuildContext context,
  MobileScannerController controller,
  AddViewModel viewModel,
) {
  controller.stop();

  // Utility function to pass to downwards widgets
  void exitPopup(BuildContext localContext) {
    Navigator.of(localContext).pop();
    controller.start();
  }

  return showDialog(
    context: context,
    barrierDismissible: false,
    builder: (context) =>
        OwnerPopup(viewModel: viewModel, exitPopup: exitPopup),
  );
}