import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flux/core/blocs/session/session_cubit.dart';
import 'package:flux/features/attachments/blocs/attachments_bloc.dart';
import 'package:flux/features/operations/blocs/operations_cubit.dart';
import 'package:flux/features/operations/models/operation_model.dart';
import 'package:flux/core/widgets/shared_forms/shared_customer_section.dart';
import 'package:flux/features/operations/ui/widgets/details_section.dart';
import 'package:flux/core/widgets/shared_forms/shared_attachments_section.dart';
import 'package:flux/core/widgets/shared_forms/shared_staff_section.dart';
import 'package:get_it/get_it.dart';

class OperationFormScreen extends StatefulWidget {
  final String? operationId;
  final OperationModel? existingOperation;

  const OperationFormScreen({
    super.key,
    this.operationId,
    this.existingOperation,
  });

  @override
  State<OperationFormScreen> createState() => _OperationFormScreenState();
}

class _OperationFormScreenState extends State<OperationFormScreen> {
  final _formKey = GlobalKey<FormState>();

  final _referenceController = TextEditingController();
  final _noteController = TextEditingController();
  final _freeTextSubtypeController = TextEditingController();
  final _freeTextDescriptionController = TextEditingController();

  final List<String> _availableTypes = [
    'AL',
    'MNP',
    'NIP',
    'UNICA',
    'TELEPASS',
    'Energy',
    'Fin',
    'Entertainment',
    'Custom',
  ];

  bool _isInitialized = false;

  @override
  void initState() {
    super.initState();
    final cubit = context.read<OperationsCubit>();
    final currentLoggedStaff = GetIt.I
        .get<SessionCubit>()
        .state
        .currentStaffMember!;

    // 1. Diciamo al Cubit di prepararsi
    cubit.initOperationForm(
      existingOperation: widget.existingOperation,
      operationId: widget.operationId,
      staffId: currentLoggedStaff.id,
      staffDisplayName: currentLoggedStaff.name,
    );

    // 2. IL TRUCCO MAGICO:
    // Se abbiamo passato existingOperation, il Cubit si è appena aggiornato.
    // Lo stato è già pronto, quindi sincronizziamo i controller SUBITO!
    if (cubit.state.currentOperation != null) {
      _syncTextControllers(cubit.state.currentOperation!);
    }
  }

  @override
  void dispose() {
    _referenceController.dispose();
    _noteController.dispose();
    _freeTextSubtypeController.dispose();
    super.dispose();
  }

  void _syncTextControllers(OperationModel model) {
    if (_referenceController.text.isEmpty && model.reference.isNotEmpty) {
      _referenceController.text = model.reference;
    }
    if (_noteController.text.isEmpty && model.note.isNotEmpty) {
      _noteController.text = model.note;
    }
    if (_freeTextSubtypeController.text.isEmpty &&
        model.subtype != null &&
        model.subtype!.isNotEmpty) {
      _freeTextSubtypeController.text = model.subtype!;
    }
    if (_freeTextDescriptionController.text.isEmpty &&
        model.description != null &&
        model.description!.isNotEmpty) {
      _freeTextDescriptionController.text = model.description!;
    }
    _isInitialized = true;
  }

  void _saveOperation({required bool keepAdding}) {
    if (_formKey.currentState!.validate()) {
      final cubit = context.read<OperationsCubit>();
      final currentOperation = cubit.state.currentOperation!;

      final operationToSave = currentOperation.copyWith(
        reference: _referenceController.text,
        note: _noteController.text,
        subtype: ['Entertainment', 'Custom'].contains(currentOperation.type)
            ? _freeTextSubtypeController.text
            : currentOperation.subtype,
        description: ['Energy', 'Custom'].contains(currentOperation.type)
            ? _freeTextDescriptionController.text
            : currentOperation.description,
      );

      cubit.initOperationForm(existingOperation: operationToSave);
      cubit.saveCurrentOperation(
        targetStatus: OperationStatus.ok,
        shouldPop: !keepAdding,
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return BlocConsumer<OperationsCubit, OperationsState>(
      listenWhen: (previous, current) =>
          previous.status != current.status ||
          previous.currentOperation?.id != current.currentOperation?.id,
      listener: (context, state) {
        if (state.status == OperationsStatus.ready &&
            state.currentOperation != null &&
            !_isInitialized) {
          _syncTextControllers(state.currentOperation!);
        }

        if (state.status == OperationsStatus.saved) {
          Navigator.of(context).pop();
        } else if (state.status == OperationsStatus.savedNoPop) {
          context.read<OperationsCubit>().prepareNextOperationInBatch();
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(
              content: Text('Servizio aggiunto! Inserisci il prossimo.'),
            ),
          );
          _freeTextSubtypeController.clear();
          _freeTextDescriptionController.clear();
        } else if (state.status == OperationsStatus.failure) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(
              content: Text(state.errorMessage ?? 'Errore'),
              backgroundColor: theme.colorScheme.error,
            ),
          );
        }
      },
      builder: (context, state) {
        if (!_isInitialized &&
            (widget.operationId != null || widget.existingOperation != null) &&
            state.status == OperationsStatus.loading) {
          return const Scaffold(
            body: Center(child: CircularProgressIndicator()),
          );
        }

        return Scaffold(
          appBar: AppBar(
            title: Text(
              state.currentOperation?.id == null
                  ? 'Nuova Pratica'
                  : 'Modifica Pratica',
            ),
          ),
          body: Form(
            key: _formKey,
            child: LayoutBuilder(
              builder: (context, constraints) {
                final isUltraWide = constraints.maxWidth > 1400;
                final isDesktop = constraints.maxWidth > 900;
                if (isUltraWide) {
                  // --- LAYOUT 3 COLONNE (Schermi giganti) ---
                  return Row(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      // 1. FORM PRINCIPALE (40%)
                      Expanded(
                        flex: 4,
                        child: SingleChildScrollView(
                          padding: const EdgeInsets.all(16.0),
                          // Attenzione: devi togliere la sezione file dal _buildMainFormContent!
                          child: _buildMainFormContent(
                            theme,
                            state,
                            showFiles: false,
                          ),
                        ),
                      ),
                      VerticalDivider(width: 1, color: theme.dividerColor),

                      // 2. NOTE (30%)
                      Expanded(
                        flex: 3,
                        child: Padding(
                          padding: const EdgeInsets.all(16.0),
                          child: _buildNotesSection(isDesktop: true),
                        ),
                      ),
                      VerticalDivider(width: 1, color: theme.dividerColor),

                      // 3. FILE (30%)
                      Expanded(
                        flex: 3,
                        child: SingleChildScrollView(
                          padding: const EdgeInsets.all(16.0),
                          child: SharedAttachmentsSection(
                            parentType: AttachmentParentType.operation,
                            parentId: state.currentOperation?.id,
                          ),
                        ),
                      ),
                    ],
                  );
                } else if (isDesktop) {
                  return Row(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Expanded(
                        flex: 7,
                        child: SingleChildScrollView(
                          padding: const EdgeInsets.all(16.0),
                          child: _buildMainFormContent(theme, state),
                        ),
                      ),
                      VerticalDivider(width: 1, color: theme.dividerColor),
                      Expanded(
                        flex: 3,
                        child: Padding(
                          padding: const EdgeInsets.all(16.0),
                          child: _buildNotesSection(isDesktop: true),
                        ),
                      ),
                    ],
                  );
                } else {
                  return SingleChildScrollView(
                    padding: const EdgeInsets.all(16.0),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        _buildMainFormContent(theme, state),
                        const Divider(height: 32),
                        _buildNotesSection(isDesktop: false),
                        const SizedBox(height: 80),
                      ],
                    ),
                  );
                }
              },
            ),
          ),
          bottomNavigationBar: SafeArea(
            child: Padding(
              padding: const EdgeInsets.all(16.0),
              child: Row(
                children: [
                  Expanded(
                    flex: 1,
                    child: OutlinedButton(
                      onPressed: state.status == OperationsStatus.saving
                          ? null
                          : () => _saveOperation(keepAdding: true),
                      child: const Text(
                        'Salva e Aggiungi Altro',
                        textAlign: TextAlign.center,
                      ),
                    ),
                  ),
                  const SizedBox(width: 12),
                  Expanded(
                    flex: 1,
                    child: ElevatedButton(
                      onPressed: state.status == OperationsStatus.saving
                          ? null
                          : () => _saveOperation(keepAdding: false),
                      child: state.status == OperationsStatus.saving
                          ? const SizedBox(
                              width: 20,
                              height: 20,
                              child: CircularProgressIndicator(
                                color: Colors.white,
                                strokeWidth: 2,
                              ),
                            )
                          : const Text('Salva ed Esci'),
                    ),
                  ),
                ],
              ),
            ),
          ),
        );
      },
    );
  }

  Widget _buildMainFormContent(
    ThemeData theme,
    OperationsState state, {
    bool showFiles = true,
  }) {
    final currentOp = state.currentOperation;
    final currentType = currentOp?.type ?? 'AL';

    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        StaffSection(
          staffId: currentOp?.staffId,
          staffName: currentOp?.staffDisplayName,
          onStaffSelected: (staff) => {
            context.read<OperationsCubit>().updateOperationFields(
              staffId: staff.id,
              staffDisplayName: staff.name,
            ),
          },
        ),
        const Divider(height: 50),
        _buildSectionTitle('Cliente & Riferimento'),
        SharedCustomerSection(
          customerId: currentOp?.customerId,
          customerName: currentOp?.customerDisplayName,
          onCustomerSelected: (customer) {
            context.read<OperationsCubit>().updateOperationFields(
              customerId: customer.id,
              customerDisplayName: customer.name,
            );
          },
        ),
        const SizedBox(height: 16),
        TextFormField(
          controller: _referenceController,
          decoration: const InputDecoration(
            labelText: 'Riferimento (es. numero di telefono, targa...)',
            prefixIcon: Icon(Icons.tag),
          ),
        ),
        const Divider(height: 32),

        _buildSectionTitle('Cosa stiamo facendo?'),
        Wrap(
          spacing: 8.0,
          runSpacing: 8.0,
          children: _availableTypes.map((type) {
            return ChoiceChip(
              label: Text(type),
              selected: currentType == type,
              onSelected: (selected) {
                if (selected) {
                  context.read<OperationsCubit>().setTypeWithSmartDefault(type);
                }
              },
            );
          }).toList(),
        ),
        const Divider(height: 32),

        _buildSectionTitle('Dettagli Servizio'),
        DetailsSection(
          currentOp: currentOp,
          currentType: currentType,
          freeTextSubtypeController: _freeTextSubtypeController,
          freeTextDescriptionController: _freeTextDescriptionController,
          durationQuickPicks: _buildDurationQuickPicks(currentOp),
        ),

        // QUANTITÀ
        Row(
          children: [
            const Text('Quantità: '),
            IconButton(
              icon: const Icon(Icons.remove),
              onPressed: () {
                final q = currentOp?.quantity ?? 1;
                if (q > 1) {
                  context.read<OperationsCubit>().updateOperationFields(
                    quantity: q - 1,
                  );
                }
              },
            ),
            Text(
              '${currentOp?.quantity ?? 1}',
              style: const TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
            ),
            IconButton(
              icon: const Icon(Icons.add),
              onPressed: () {
                final q = currentOp?.quantity ?? 1;
                context.read<OperationsCubit>().updateOperationFields(
                  quantity: q + 1,
                );
              },
            ),
          ],
        ),
        const Divider(height: 32),

        if (showFiles) ...[
          SharedAttachmentsSection(
            parentType: AttachmentParentType.operation,
            parentId: currentOp?.id,
          ),
        ],
      ],
    );
  }

  Widget _buildDurationQuickPicks(OperationModel? currentOp) {
    final durations = [3, 6, 12, 24, 30, 36, 48];
    return Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        const Text(
          "Imposta durata rapida (mesi):",
          style: TextStyle(
            fontSize: 12,
            fontWeight: FontWeight.w600,
            color: Colors.grey,
          ),
        ),
        const SizedBox(height: 8),
        SingleChildScrollView(
          scrollDirection: Axis.horizontal,
          child: Row(
            children: durations.map((months) {
              return Padding(
                padding: const EdgeInsets.only(right: 8.0),
                child: ActionChip(
                  label: Text("$months m"),
                  backgroundColor: Colors.blue.withValues(alpha: 0.05),
                  onPressed: () {
                    final now = DateTime.now();
                    context.read<OperationsCubit>().updateOperationFields(
                      expirationDate: DateTime(
                        now.year,
                        now.month + months,
                        now.day,
                      ),
                    );
                  },
                ),
              );
            }).toList(),
          ),
        ),
      ],
    );
  }

  Widget _buildNotesSection({required bool isDesktop}) {
    final title = _buildSectionTitle('Note Interne');
    final noteField = TextFormField(
      controller: _noteController,
      keyboardType: TextInputType.multiline,
      minLines: isDesktop ? null : 5,
      maxLines: null,
      expands: isDesktop,
      textAlignVertical: TextAlignVertical.top,
      decoration: const InputDecoration(
        hintText: 'Incolla qui seriali, ICCID, IBAN, indirizzi...',
        alignLabelWithHint: true,
        border: OutlineInputBorder(),
      ),
    );
    return isDesktop
        ? Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              title,
              const SizedBox(height: 8),
              Expanded(child: noteField),
            ],
          )
        : Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [title, const SizedBox(height: 8), noteField],
          );
  }

  Widget _buildSectionTitle(String title) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 12.0),
      child: Text(
        title,
        style: Theme.of(
          context,
        ).textTheme.titleLarge?.copyWith(fontWeight: FontWeight.bold),
      ),
    );
  }
}