import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../../../core/errors/failure.dart';
import '../../../../core/utils/formatters.dart';
import '../../../../core/utils/validators.dart';
import '../../../../shared/models/asset_model.dart';
import '../../../../shared/models/user_management_models.dart'
    show FilterOptionModel;
import '../../../../shared/widgets/api_feedback.dart';
import '../../../../shared/widgets/app_button.dart';
import '../../../../shared/widgets/app_card.dart';
import '../../../../shared/widgets/app_date_popup.dart';
import '../../../../shared/widgets/app_dropdown.dart';
import '../../../../shared/widgets/app_empty_state.dart';
import '../../../../shared/widgets/app_form_toggle_field.dart';
import '../../../../shared/widgets/app_searchable_dropdown.dart';
import '../../../../shared/widgets/app_side_panel.dart';
import '../../../../shared/widgets/app_text_field.dart';
import '../../../../shared/widgets/error_view.dart';
import '../providers/asset_form_lookups_provider.dart';
import '../providers/assets_provider.dart';

class AddAmcPanel extends ConsumerStatefulWidget {
  const AddAmcPanel({
    super.key,
    required this.assetId,
    this.contractId,
  });

  final String assetId;
  final String? contractId;

  bool get isEdit => contractId != null;

  @override
  ConsumerState<AddAmcPanel> createState() => _AddAmcPanelState();
}

class _AddAmcPanelState extends ConsumerState<AddAmcPanel> {
  final _formKey = GlobalKey<FormState>();
  final _contractNoController = TextEditingController();
  final _annualCostController = TextEditingController();
  final _visitsPerYearController = TextEditingController();
  final _contactPersonController = TextEditingController();
  final _contactPhoneController = TextEditingController();
  final _contactEmailController = TextEditingController();
  final _scopeOfWorkController = TextEditingController();
  final _exclusionsController = TextEditingController();
  final _remarksController = TextEditingController();
  DateTime? _startDate;
  DateTime? _endDate;
  DateTime? _renewalDate;
  int? _vendorId;
  String? _contractType;
  String? _paymentFrequency;
  String? _serviceFrequency;
  bool _isActive = true;
  bool _isSubmitting = false;
  String? _populatedContractId;

  @override
  void dispose() {
    _contractNoController.dispose();
    _annualCostController.dispose();
    _visitsPerYearController.dispose();
    _contactPersonController.dispose();
    _contactPhoneController.dispose();
    _contactEmailController.dispose();
    _scopeOfWorkController.dispose();
    _exclusionsController.dispose();
    _remarksController.dispose();
    super.dispose();
  }

  void _populateFromContract(AmcContractModel contract) {
    if (_populatedContractId == contract.id) return;
    _populatedContractId = contract.id;

    _vendorId = contract.vendorId;
    _contractNoController.text = contract.contractNo ?? '';
    _contractType = contract.contractType;
    _startDate = contract.startDate;
    _endDate = contract.endDate;
    _renewalDate = contract.renewalDate;
    if (contract.annualCost != null) {
      _annualCostController.text =
          CurrencyFormatter.formatEditable(contract.annualCost);
    }
    _paymentFrequency = contract.paymentFrequency;
    _serviceFrequency = contract.serviceFrequency;
    if (contract.visitsPerYear != null) {
      _visitsPerYearController.text = contract.visitsPerYear.toString();
    }
    _contactPersonController.text = contract.contactPerson ?? '';
    _contactPhoneController.text = contract.contactPhone ?? '';
    _contactEmailController.text = contract.contactEmail ?? '';
    _scopeOfWorkController.text = contract.scopeOfWork ?? '';
    _exclusionsController.text = contract.exclusions ?? '';
    _remarksController.text = contract.remarks ?? '';
    _isActive = contract.isActive;
  }

  Map<String, dynamic> _buildPayload() {
    final annualCost = CurrencyFormatter.tryParse(_annualCostController.text);
    final visitsPerYear = int.tryParse(_visitsPerYearController.text.trim());
    return {
      'vendor_id': _vendorId,
      if (_contractNoController.text.isNotEmpty)
        'contract_no': _contractNoController.text.trim(),
      if (_contractType != null && _contractType!.trim().isNotEmpty)
        'contract_type': _contractType,
      'start_date': DateFormatter.toApiDate(_startDate!),
      'end_date': DateFormatter.toApiDate(_endDate!),
      if (_renewalDate != null) 'renewal_date': DateFormatter.toApiDate(_renewalDate!),
      if (annualCost != null) 'annual_cost': annualCost,
      if (_paymentFrequency != null && _paymentFrequency!.trim().isNotEmpty)
        'payment_frequency': _paymentFrequency,
      if (_serviceFrequency != null && _serviceFrequency!.trim().isNotEmpty)
        'service_frequency': _serviceFrequency,
      if (visitsPerYear != null) 'visits_per_year': visitsPerYear,
      if (_contactPersonController.text.trim().isNotEmpty)
        'contact_person': _contactPersonController.text.trim(),
      if (_contactPhoneController.text.trim().isNotEmpty)
        'contact_phone': _contactPhoneController.text.trim(),
      if (_contactEmailController.text.trim().isNotEmpty)
        'contact_email': _contactEmailController.text.trim(),
      if (_scopeOfWorkController.text.trim().isNotEmpty)
        'scope_of_work': _scopeOfWorkController.text.trim(),
      if (_exclusionsController.text.trim().isNotEmpty)
        'exclusions': _exclusionsController.text.trim(),
      if (_remarksController.text.trim().isNotEmpty)
        'remarks': _remarksController.text.trim(),
      'is_active': _isActive,
    };
  }

  Future<void> _pickDate({
    required DateTime? current,
    required void Function(DateTime date) onPicked,
    DateTime? firstDate,
    DateTime? lastDate,
  }) async {
    final first = firstDate ?? DateTime(2000);
    final last = lastDate ?? DateTime(2100);
    var initial = current ?? DateTime.now();
    if (initial.isBefore(first)) initial = first;
    if (initial.isAfter(last)) initial = last;

    final picked = await showAppDatePopup(
      context: context,
      initialDate: initial,
      firstDate: first,
      lastDate: last,
      helpText: 'Select date',
    );
    if (picked != null) {
      setState(() => onPicked(picked));
    }
  }

  void _onStartDatePicked(DateTime date) {
    final clearedEnd = _endDate != null &&
        DateTime(_endDate!.year, _endDate!.month, _endDate!.day)
            .isBefore(DateTime(date.year, date.month, date.day));
    _startDate = date;
    if (clearedEnd) {
      _endDate = null;
      WidgetsBinding.instance.addPostFrameCallback((_) {
        if (!mounted) return;
        showSidePanelSnackBar(
          context,
          'End date cleared. Please select an end date on or after the start date.',
        );
      });
    }
  }

  Future<void> _save() async {
    if (!_formKey.currentState!.validate()) return;
    if (_startDate == null || _endDate == null) {
      showSidePanelSnackBar(context, 'Please select start and end dates');
      return;
    }
    if (DateTime(_endDate!.year, _endDate!.month, _endDate!.day).isBefore(
      DateTime(_startDate!.year, _startDate!.month, _startDate!.day),
    )) {
      showSidePanelSnackBar(
        context,
        'End date cannot be earlier than start date',
      );
      return;
    }

    if (_vendorId == null) {
      showSidePanelSnackBar(context, 'Please select a vendor');
      return;
    }

    setState(() => _isSubmitting = true);
    try {
      final payload = _buildPayload();
      final notifier = ref.read(assetDetailProvider(widget.assetId).notifier);
      if (widget.isEdit) {
        await notifier.updateAmc(widget.contractId!, payload);
      } else {
        await notifier.createAmc(payload);
      }
      if (mounted) Navigator.of(context, rootNavigator: true).pop(true);
    } catch (e) {
      if (mounted) {
        showSidePanelApiError(context, e);
      }
    } finally {
      if (mounted) setState(() => _isSubmitting = false);
    }
  }

  Widget _buildForm() {
    final lookupsAsync = ref.watch(assetFormLookupsProvider);
    final options = lookupsAsync.valueOrNull?.options ?? const AssetDropdownOptionsModel();

    if (lookupsAsync.hasValue) {
      final nextContractType = resolveAssetOptionValue(
        _contractType,
        options.contractTypes,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      final nextPaymentFrequency = resolveAssetOptionValue(
        _paymentFrequency,
        options.paymentFrequencies,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      final nextServiceFrequency = resolveAssetOptionValue(
        _serviceFrequency,
        options.serviceFrequencies,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      if (nextContractType != _contractType ||
          nextPaymentFrequency != _paymentFrequency ||
          nextServiceFrequency != _serviceFrequency) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (!mounted) return;
          setState(() {
            _contractType = nextContractType;
            _paymentFrequency = nextPaymentFrequency;
            _serviceFrequency = nextServiceFrequency;
          });
        });
      }
    }

    return Form(
      key: _formKey,
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          SidePanelFormRow(
            left: lookupsAsync.when(
              loading: () => const LinearProgressIndicator(),
              error: (_, __) => const Text('Failed to load vendors'),
              data: (lookups) => AppSearchableDropdown<int>(
                label: 'Vendor *',
                value: _vendorId,
                searchHint: 'Search vendor...',
                options: lookups.vendors
                    .map((vendor) => AppDropdownOption(
                          value: int.tryParse(vendor.id) ?? 0,
                          label: vendor.name,
                        ))
                    .where((option) => option.value != 0)
                    .toList(),
                onChanged: (v) => setState(() => _vendorId = v),
                validator: (v) => v == null ? 'Vendor is required' : null,
              ),
            ),
            right: AppTextField(
              controller: _contractNoController,
              label: 'Contract No',
            ),
          ),
          AppSearchableDropdown<String>(
            label: 'Contract Type',
            value: _contractType,
            searchHint: 'Search contract type...',
            options: assetOptionDropdowns(options.contractTypes),
            enabled: options.contractTypes.isNotEmpty,
            onChanged: (v) {
              if (v != null) setState(() => _contractType = v);
            },
            validator: (v) =>
                options.contractTypes.isEmpty ? null : (v == null ? 'Contract type is required' : null),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: _SidePanelDateField(
              label: 'Start Date',
              isRequired: true,
              value: _startDate,
              onPick: () => _pickDate(
                current: _startDate,
                onPicked: _onStartDatePicked,
              ),
            ),
            right: _SidePanelDateField(
              label: 'End Date',
              isRequired: true,
              value: _endDate,
              onPick: () => _pickDate(
                current: _endDate,
                firstDate: _startDate ?? DateTime(2000),
                onPicked: (date) => _endDate = date,
              ),
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: _SidePanelDateField(
              label: 'Renewal Date',
              value: _renewalDate,
              onPick: () => _pickDate(
                current: _renewalDate,
                onPicked: (date) => _renewalDate = date,
              ),
            ),
            right: AppTextField(
              controller: _annualCostController,
              label: 'Annual Cost',
              keyboardType: const TextInputType.numberWithOptions(decimal: true),
              inputFormatters: CurrencyFormatter.amountInput,
              validator: (v) => Validators.optionalNonNegativeDouble(
                v,
                fieldName: 'Annual Cost',
              ),
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: AppSearchableDropdown<String>(
              label: 'Payment Frequency',
              value: _paymentFrequency,
              searchHint: 'Search payment frequency...',
              options: assetOptionDropdowns(options.paymentFrequencies),
              enabled: options.paymentFrequencies.isNotEmpty,
              onChanged: (v) => setState(() => _paymentFrequency = v),
            ),
            right: AppSearchableDropdown<String>(
              label: 'Service Frequency',
              value: _serviceFrequency,
              searchHint: 'Search service frequency...',
              options: assetOptionDropdowns(options.serviceFrequencies),
              enabled: options.serviceFrequencies.isNotEmpty,
              onChanged: (v) => setState(() => _serviceFrequency = v),
            ),
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _visitsPerYearController,
            label: 'Visits Per Year',
            keyboardType: TextInputType.number,
            validator: (v) => Validators.optionalPositiveInt(
              v,
              fieldName: 'Visits Per Year',
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: AppTextField(
              controller: _contactPersonController,
              label: 'Contact Person',
            ),
            right: AppTextField(
              controller: _contactPhoneController,
              label: 'Contact Phone',
              keyboardType: TextInputType.phone,
              validator: Validators.optionalMobile,
              inputFormatters: Validators.mobileInput,
            ),
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _contactEmailController,
            label: 'Contact Email',
            keyboardType: TextInputType.emailAddress,
            validator: Validators.optionalEmail,
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _scopeOfWorkController,
            label: 'Scope Of Work',
            maxLines: 3,
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _exclusionsController,
            label: 'Exclusions',
            maxLines: 3,
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _remarksController,
            label: 'Remarks',
            maxLines: 3,
          ),
          const SizedBox(height: 8),
          AppFormToggleField(
            label: 'Active',
            value: _isActive,
            onChanged: (value) => setState(() => _isActive = value),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    if (widget.isEdit) {
      final contractAsync = ref.watch(
        amcContractFormProvider((
          assetId: widget.assetId,
          contractId: widget.contractId!,
        )),
      );
      return contractAsync.when(
        loading: () => SidePanelScaffold(
          title: 'Edit AMC Contract',
          footer: _panelFooter(
            context,
            isSubmitting: true,
            saveLabel: 'Update AMC Contract',
            onSave: () {},
          ),
          child: const Center(child: CircularProgressIndicator()),
        ),
        error: (error, _) => SidePanelScaffold(
          title: 'Edit AMC Contract',
          child: Center(child: Text(error.toString())),
        ),
        data: (contract) {
          _populateFromContract(contract);
          return SidePanelScaffold(
            title: 'Edit AMC Contract',
            footer: _panelFooter(
              context,
              isSubmitting: _isSubmitting,
              saveLabel: 'Update AMC Contract',
              onSave: _save,
            ),
            child: _buildForm(),
          );
        },
      );
    }

    return SidePanelScaffold(
      title: 'Add AMC Contract',
      footer: _panelFooter(
        context,
        isSubmitting: _isSubmitting,
        saveLabel: 'Save AMC Contract',
        onSave: _save,
      ),
      child: _buildForm(),
    );
  }
}

class LogServiceVisitPanel extends ConsumerStatefulWidget {
  const LogServiceVisitPanel({
    super.key,
    required this.assetId,
    this.visitId,
    this.amcContracts = const [],
  });

  final String assetId;
  final String? visitId;
  final List<AmcContractModel> amcContracts;

  bool get isEdit => visitId != null;

  @override
  ConsumerState<LogServiceVisitPanel> createState() => _LogServiceVisitPanelState();
}

class _LogServiceVisitPanelState extends ConsumerState<LogServiceVisitPanel> {
  final _formKey = GlobalKey<FormState>();
  final _complaintNoController = TextEditingController();
  final _complaintDescController = TextEditingController();
  final _engineerNameController = TextEditingController();
  final _engineerPhoneController = TextEditingController();
  final _workDoneController = TextEditingController();
  final _partsReplacedController = TextEditingController();
  final _downtimeHoursController = TextEditingController();
  final _serviceCostController = TextEditingController();
  final _remarksController = TextEditingController();
  DateTime? _visitDate = DateTime.now();
  DateTime? _complaintDate;
  DateTime? _nextServiceDate;
  int? _amcContractId;
  int? _vendorId;
  String? _visitType;
  String? _status;
  String? _assetConditionAfter;
  bool _isUnderAmc = false;
  bool _isSubmitting = false;
  String? _populatedVisitId;

  @override
  void dispose() {
    _complaintNoController.dispose();
    _complaintDescController.dispose();
    _engineerNameController.dispose();
    _engineerPhoneController.dispose();
    _workDoneController.dispose();
    _partsReplacedController.dispose();
    _downtimeHoursController.dispose();
    _serviceCostController.dispose();
    _remarksController.dispose();
    super.dispose();
  }

  void _populateFromVisit(ServiceVisitModel visit) {
    if (_populatedVisitId == visit.id) return;
    _populatedVisitId = visit.id;

    _visitType = visit.visitType;
    _visitDate = visit.visitDate;
    _amcContractId = visit.amcContractId;
    _complaintNoController.text = visit.complaintNo ?? '';
    _complaintDate = visit.complaintDate;
    _complaintDescController.text = visit.complaintDesc ?? '';
    _engineerNameController.text = visit.engineerName ?? '';
    _engineerPhoneController.text = visit.engineerPhone ?? '';
    _vendorId = visit.vendorId;
    _workDoneController.text = visit.workDone ?? '';
    _partsReplacedController.text = visit.partsReplaced ?? '';
    _nextServiceDate = visit.nextServiceDate;
    _status = visit.status;
    if (visit.downtimeHours != null) {
      _downtimeHoursController.text = visit.downtimeHours.toString();
    }
    if (visit.serviceCost != null) {
      _serviceCostController.text =
          CurrencyFormatter.formatEditable(visit.serviceCost);
    }
    _isUnderAmc = visit.isUnderAmc || visit.amcContractId != null;
    _assetConditionAfter = visit.assetConditionAfter;
    _remarksController.text = visit.remarks ?? '';
  }

  Future<void> _pickDate({
    required DateTime? current,
    required void Function(DateTime date) onPicked,
  }) async {
    final picked = await showAppDatePopup(
      context: context,
      initialDate: current ?? DateTime.now(),
      firstDate: DateTime(2000),
      lastDate: DateTime(2100),
      helpText: 'Select date',
    );
    if (picked != null) {
      setState(() => onPicked(picked));
    }
  }

  Map<String, dynamic> _buildPayload() {
    final downtimeHours =
        CurrencyFormatter.tryParse(_downtimeHoursController.text);
    final serviceCost =
        CurrencyFormatter.tryParse(_serviceCostController.text);
    return {
      if (_visitType != null && _visitType!.trim().isNotEmpty)
        'visit_type': _visitType,
      'visit_date': DateFormatter.toApiDate(_visitDate!),
      if (_isUnderAmc && _amcContractId != null)
        'amc_contract_id': _amcContractId,
      if (_complaintNoController.text.trim().isNotEmpty)
        'complaint_no': _complaintNoController.text.trim(),
      if (_complaintDate != null)
        'complaint_date': DateFormatter.toApiDate(_complaintDate!),
      if (_complaintDescController.text.trim().isNotEmpty)
        'complaint_desc': _complaintDescController.text.trim(),
      if (_engineerNameController.text.trim().isNotEmpty)
        'engineer_name': _engineerNameController.text.trim(),
      if (_engineerPhoneController.text.trim().isNotEmpty)
        'engineer_phone': _engineerPhoneController.text.trim(),
      if (_vendorId != null) 'vendor_id': _vendorId,
      if (_workDoneController.text.trim().isNotEmpty)
        'work_done': _workDoneController.text.trim(),
      if (_partsReplacedController.text.trim().isNotEmpty)
        'parts_replaced': _partsReplacedController.text.trim(),
      if (_nextServiceDate != null)
        'next_service_date': DateFormatter.toApiDate(_nextServiceDate!),
      if (_status != null && _status!.trim().isNotEmpty) 'status': _status,
      if (downtimeHours != null) 'downtime_hours': downtimeHours,
      if (serviceCost != null) 'service_cost': serviceCost,
      'is_under_amc': _isUnderAmc,
      if (_assetConditionAfter != null &&
          _assetConditionAfter!.trim().isNotEmpty)
        'asset_condition_after': _assetConditionAfter,
      if (_remarksController.text.trim().isNotEmpty)
        'remarks': _remarksController.text.trim(),
    };
  }

  Future<void> _save() async {
    if (!_formKey.currentState!.validate()) return;
    if (_visitDate == null) {
      showSidePanelSnackBar(context, 'Please select visit date');
      return;
    }

    setState(() => _isSubmitting = true);
    try {
      final payload = _buildPayload();
      final notifier = ref.read(assetDetailProvider(widget.assetId).notifier);
      if (widget.isEdit) {
        await notifier.updateVisit(widget.visitId!, payload);
      } else {
        await notifier.logVisit(payload);
      }
      if (mounted) Navigator.of(context, rootNavigator: true).pop(true);
    } catch (e) {
      if (mounted) {
        showSidePanelApiError(context, e);
      }
    } finally {
      if (mounted) setState(() => _isSubmitting = false);
    }
  }

  void _setUnderAmc(bool value) {
    setState(() {
      _isUnderAmc = value;
      if (!value) {
        _amcContractId = null;
      }
    });
  }

  void _onAmcContractChanged(
    int? contractId,
    List<AmcContractModel> amcContracts,
  ) {
    setState(() {
      _amcContractId = contractId;
      if (contractId == null) return;
      final contract = amcContracts
          .where((c) => int.tryParse(c.id) == contractId)
          .firstOrNull;
      if (contract?.vendorId != null) {
        _vendorId = contract!.vendorId;
      }
    });
  }

  List<AppDropdownOption<int>> _vendorOptions({
    required List<FilterOptionModel> vendors,
    required List<AmcContractModel> amcContracts,
  }) {
    final all = vendors
        .map(
          (vendor) => AppDropdownOption(
            value: int.tryParse(vendor.id) ?? 0,
            label: vendor.name,
          ),
        )
        .where((option) => option.value != 0)
        .toList();

    if (!_isUnderAmc || _amcContractId == null) return all;

    final contract = amcContracts
        .where((c) => int.tryParse(c.id) == _amcContractId)
        .firstOrNull;
    final contractVendorId = contract?.vendorId;
    if (contractVendorId == null) return all;

    return all.where((option) => option.value == contractVendorId).toList();
  }

  Widget _buildForm(List<AmcContractModel> amcContracts) {
    final lookupsAsync = ref.watch(assetFormLookupsProvider);
    final options =
        lookupsAsync.valueOrNull?.options ?? const AssetDropdownOptionsModel();

    if (lookupsAsync.hasValue) {
      final nextVisitType = resolveAssetOptionValue(
        _visitType,
        options.visitTypes,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      final nextStatus = resolveAssetOptionValue(
        _status,
        options.visitStatuses,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      final nextConditionAfter = resolveAssetOptionValue(
        _assetConditionAfter,
        options.visitConditionsAfter,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      if (nextVisitType != _visitType ||
          nextStatus != _status ||
          nextConditionAfter != _assetConditionAfter) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (!mounted) return;
          setState(() {
            _visitType = nextVisitType;
            _status = nextStatus;
            _assetConditionAfter = nextConditionAfter;
          });
        });
      }
    }

    return Form(
      key: _formKey,
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          // 1) Visit classification
          SidePanelFormRow(
            left: AppSearchableDropdown<String>(
              label: 'Visit Type *',
              value: _visitType,
              searchHint: 'Search visit type...',
              options: assetOptionDropdowns(options.visitTypes),
              enabled: options.visitTypes.isNotEmpty,
              onChanged: (v) {
                if (v != null) setState(() => _visitType = v);
              },
              validator: (v) => v == null ? 'Visit type is required' : null,
            ),
            right: AppSearchableDropdown<String>(
              label: 'Status',
              value: _status,
              searchHint: 'Search status...',
              options: assetOptionDropdowns(options.visitStatuses),
              enabled: options.visitStatuses.isNotEmpty,
              onChanged: (v) {
                if (v != null) setState(() => _status = v);
              },
            ),
          ),
          _SidePanelDateField(
            label: 'Visit Date',
            isRequired: true,
            value: _visitDate,
            onPick: () => _pickDate(
              current: _visitDate,
              onPicked: (date) => setState(() => _visitDate = date),
            ),
          ),
          const SizedBox(height: 8),

          // 2) Contract & Vendor
          AppFormToggleField(
            label: 'Under AMC',
            value: _isUnderAmc,
            onChanged: _setUnderAmc,
          ),
          if (_isUnderAmc) ...[
            const SizedBox(height: 8),
            AppSearchableDropdown<int>(
              label: 'AMC Contract',
              value: _amcContractId,
              searchHint: 'Search AMC contract...',
              options: amcContracts
                  .map((contract) {
                    final id = int.tryParse(contract.id);
                    if (id == null) return null;
                    final label =
                        contract.contractNo?.trim().isNotEmpty == true
                            ? contract.contractNo!
                            : 'AMC #${contract.id}';
                    return AppDropdownOption(value: id, label: label);
                  })
                  .whereType<AppDropdownOption<int>>()
                  .toList(),
              onChanged: (v) => _onAmcContractChanged(v, amcContracts),
            ),
          ],
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: lookupsAsync.when(
              loading: () => const Padding(
                padding: EdgeInsets.only(top: 8),
                child: LinearProgressIndicator(),
              ),
              error: (_, __) => const Text('Failed to load vendors'),
              data: (lookups) => AppSearchableDropdown<int>(
                label: 'Vendor',
                value: _vendorId,
                searchHint: 'Search vendor...',
                options: _vendorOptions(
                  vendors: lookups.vendors,
                  amcContracts: amcContracts,
                ),
                onChanged: (v) => setState(() => _vendorId = v),
              ),
            ),
            right: AppSearchableDropdown<String>(
              label: 'Asset Condition After',
              value: _assetConditionAfter,
              searchHint: 'Search condition...',
              options: assetOptionDropdowns(options.visitConditionsAfter),
              enabled: options.visitConditionsAfter.isNotEmpty,
              onChanged: (v) => setState(() => _assetConditionAfter = v),
            ),
          ),

          // 3) Complaint intake
          SidePanelFormRow(
            left: AppTextField(
              controller: _complaintNoController,
              label: 'Complaint No',
            ),
            right: _SidePanelDateField(
              label: 'Complaint Date',
              value: _complaintDate,
              onPick: () => _pickDate(
                current: _complaintDate,
                onPicked: (date) => setState(() => _complaintDate = date),
              ),
            ),
          ),
          AppTextField(
            controller: _complaintDescController,
            label: 'Complaint Description',
            maxLines: 3,
          ),
          const SizedBox(height: 12),

          // 4) Engineer & work performed
          SidePanelFormRow(
            left: AppTextField(
              controller: _engineerNameController,
              label: 'Engineer Name',
            ),
            right: AppTextField(
              controller: _engineerPhoneController,
              label: 'Engineer Phone',
              keyboardType: TextInputType.phone,
              validator: Validators.optionalMobile,
              inputFormatters: Validators.mobileInput,
            ),
          ),
          AppTextField(
            controller: _workDoneController,
            label: 'Work Done',
            maxLines: 3,
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _partsReplacedController,
            label: 'Parts Replaced',
            maxLines: 3,
          ),
          const SizedBox(height: 12),

          // 5) Outcome & cost
          SidePanelFormRow(
            left: _SidePanelDateField(
              label: 'Next Service Date',
              value: _nextServiceDate,
              onPick: () => _pickDate(
                current: _nextServiceDate,
                onPicked: (date) => setState(() => _nextServiceDate = date),
              ),
            ),
            right: AppTextField(
              controller: _downtimeHoursController,
              label: 'Downtime Hours',
              keyboardType:
                  const TextInputType.numberWithOptions(decimal: true),
              validator: (v) => Validators.optionalPositiveDouble(
                v,
                fieldName: 'Downtime Hours',
              ),
            ),
          ),
          AppTextField(
            controller: _serviceCostController,
            label: 'Service Cost',
            keyboardType: const TextInputType.numberWithOptions(decimal: true),
            inputFormatters: CurrencyFormatter.amountInput,
            validator: (v) => Validators.optionalPositiveDouble(
              v,
              fieldName: 'Service Cost',
            ),
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _remarksController,
            label: 'Remarks',
            maxLines: 3,
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    if (widget.isEdit) {
      final visitAsync = ref.watch(
        serviceVisitFormProvider((
          assetId: widget.assetId,
          visitId: widget.visitId!,
        )),
      );
      return visitAsync.when(
        loading: () => SidePanelScaffold(
          title: 'Edit Service Visit',
          footer: _panelFooter(
            context,
            isSubmitting: true,
            saveLabel: 'Update Service Visit',
            onSave: () {},
          ),
          child: const Center(child: CircularProgressIndicator()),
        ),
        error: (error, _) => SidePanelScaffold(
          title: 'Edit Service Visit',
          child: Center(child: Text(error.toString())),
        ),
        data: (visit) {
          _populateFromVisit(visit);
          return SidePanelScaffold(
            title: 'Edit Service Visit',
            footer: _panelFooter(
              context,
              isSubmitting: _isSubmitting,
              saveLabel: 'Update Service Visit',
              onSave: _save,
            ),
            child: _buildForm(widget.amcContracts),
          );
        },
      );
    }

    return SidePanelScaffold(
      title: 'Log Service Visit',
      footer: _panelFooter(
        context,
        isSubmitting: _isSubmitting,
        saveLabel: 'Log Service Visit',
        onSave: _save,
      ),
      child: _buildForm(widget.amcContracts),
    );
  }
}

class AddInsurancePanel extends ConsumerStatefulWidget {
  const AddInsurancePanel({
    super.key,
    required this.assetId,
    this.policyId,
  });

  final String assetId;
  final String? policyId;

  bool get isEdit => policyId != null;

  @override
  ConsumerState<AddInsurancePanel> createState() => _AddInsurancePanelState();
}

class _AddInsurancePanelState extends ConsumerState<AddInsurancePanel> {
  final _formKey = GlobalKey<FormState>();
  final _policyNoController = TextEditingController();
  final _insurerNameController = TextEditingController();
  final _insurerBranchController = TextEditingController();
  final _insurerContactController = TextEditingController();
  final _insurerPhoneController = TextEditingController();
  final _insurerEmailController = TextEditingController();
  final _sumInsuredController = TextEditingController();
  final _annualPremiumController = TextEditingController();
  final _remarksController = TextEditingController();
  DateTime? _startDate;
  DateTime? _endDate;
  DateTime? _renewalDate;
  DateTime? _premiumPaidDate;
  String? _policyType;
  bool _isAutoRenewal = false;
  bool _premiumPaid = false;
  bool _isActive = true;
  bool _isSubmitting = false;
  String? _populatedPolicyId;

  @override
  void dispose() {
    _policyNoController.dispose();
    _insurerNameController.dispose();
    _insurerBranchController.dispose();
    _insurerContactController.dispose();
    _insurerPhoneController.dispose();
    _insurerEmailController.dispose();
    _sumInsuredController.dispose();
    _annualPremiumController.dispose();
    _remarksController.dispose();
    super.dispose();
  }

  void _populateFromPolicy(InsurancePolicyModel policy) {
    if (_populatedPolicyId == policy.id) return;
    _populatedPolicyId = policy.id;

    _policyNoController.text = policy.policyNo;
    _insurerNameController.text = policy.insurerName;
    _insurerBranchController.text = policy.insurerBranch ?? '';
    _insurerContactController.text = policy.insurerContact ?? '';
    _insurerPhoneController.text = policy.insurerPhone ?? '';
    _insurerEmailController.text = policy.insurerEmail ?? '';
    _policyType = policy.policyType;
    if (policy.sumInsured != null) {
      _sumInsuredController.text =
          CurrencyFormatter.formatEditable(policy.sumInsured);
    }
    if (policy.annualPremium != null) {
      _annualPremiumController.text =
          CurrencyFormatter.formatEditable(policy.annualPremium);
    }
    _startDate = policy.policyStartDate;
    _endDate = policy.policyEndDate;
    _renewalDate = policy.renewalDate;
    _isAutoRenewal = policy.isAutoRenewal;
    _premiumPaid = policy.premiumPaid;
    _premiumPaidDate = policy.premiumPaidDate;
    _remarksController.text = policy.remarks ?? '';
    _isActive = policy.isActive;
  }

  Future<void> _pickDate({
    required DateTime? current,
    required void Function(DateTime date) onPicked,
    DateTime? firstDate,
    DateTime? lastDate,
  }) async {
    final first = firstDate ?? DateTime(2000);
    final last = lastDate ?? DateTime(2100);
    var initial = current ?? DateTime.now();
    if (initial.isBefore(first)) initial = first;
    if (initial.isAfter(last)) initial = last;

    final picked = await showAppDatePopup(
      context: context,
      initialDate: initial,
      firstDate: first,
      lastDate: last,
      helpText: 'Select date',
    );
    if (picked != null) {
      setState(() => onPicked(picked));
    }
  }

  void _onStartDatePicked(DateTime date) {
    final clearedEnd = _endDate != null &&
        DateTime(_endDate!.year, _endDate!.month, _endDate!.day)
            .isBefore(DateTime(date.year, date.month, date.day));
    _startDate = date;
    if (clearedEnd) {
      _endDate = null;
      WidgetsBinding.instance.addPostFrameCallback((_) {
        if (!mounted) return;
        showSidePanelSnackBar(
          context,
          'End date cleared. Please select an end date on or after the start date.',
        );
      });
    }
  }

  Map<String, dynamic> _buildPayload() {
    final sumInsured =
        CurrencyFormatter.tryParse(_sumInsuredController.text);
    final annualPremium =
        CurrencyFormatter.tryParse(_annualPremiumController.text);
    return {
      'policy_no': _policyNoController.text.trim(),
      'insurer_name': _insurerNameController.text.trim(),
      if (_insurerBranchController.text.trim().isNotEmpty)
        'insurer_branch': _insurerBranchController.text.trim(),
      if (_insurerContactController.text.trim().isNotEmpty)
        'insurer_contact': _insurerContactController.text.trim(),
      if (_insurerPhoneController.text.trim().isNotEmpty)
        'insurer_phone': _insurerPhoneController.text.trim(),
      if (_insurerEmailController.text.trim().isNotEmpty)
        'insurer_email': _insurerEmailController.text.trim(),
      if (_policyType != null && _policyType!.trim().isNotEmpty)
        'policy_type': _policyType,
      if (sumInsured != null) 'sum_insured': sumInsured,
      if (annualPremium != null) 'annual_premium': annualPremium,
      'policy_start_date': DateFormatter.toApiDate(_startDate!),
      'policy_end_date': DateFormatter.toApiDate(_endDate!),
      if (_renewalDate != null) 'renewal_date': DateFormatter.toApiDate(_renewalDate!),
      'is_auto_renewal': _isAutoRenewal,
      'premium_paid': _premiumPaid,
      if (_premiumPaidDate != null)
        'premium_paid_date': DateFormatter.toApiDate(_premiumPaidDate!),
      if (_remarksController.text.trim().isNotEmpty) 'remarks': _remarksController.text.trim(),
      'is_active': _isActive,
    };
  }

  Future<void> _save() async {
    if (!_formKey.currentState!.validate()) return;
    if (_startDate == null || _endDate == null) {
      showSidePanelSnackBar(context, 'Please select start and end dates');
      return;
    }
    if (DateTime(_endDate!.year, _endDate!.month, _endDate!.day).isBefore(
      DateTime(_startDate!.year, _startDate!.month, _startDate!.day),
    )) {
      showSidePanelSnackBar(
        context,
        'End date cannot be earlier than start date',
      );
      return;
    }

    setState(() => _isSubmitting = true);
    try {
      final payload = _buildPayload();
      final notifier = ref.read(assetDetailProvider(widget.assetId).notifier);
      if (widget.isEdit) {
        await notifier.updateInsurance(widget.policyId!, payload);
      } else {
        await notifier.createInsurance(payload);
      }
      if (mounted) Navigator.of(context, rootNavigator: true).pop(true);
    } catch (e) {
      if (mounted) {
        showSidePanelApiError(context, e);
      }
    } finally {
      if (mounted) setState(() => _isSubmitting = false);
    }
  }

  Widget _buildForm() {
    final lookupsAsync = ref.watch(assetFormLookupsProvider);
    final options = lookupsAsync.valueOrNull?.options ?? const AssetDropdownOptionsModel();

    if (lookupsAsync.hasValue) {
      final nextPolicyType = resolveAssetOptionValue(
        _policyType,
        options.policyTypes,
        preferFirstWhenEmpty: !widget.isEdit,
      );
      if (nextPolicyType != _policyType) {
        WidgetsBinding.instance.addPostFrameCallback((_) {
          if (!mounted) return;
          setState(() => _policyType = nextPolicyType);
        });
      }
    }

    return Form(
      key: _formKey,
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          SidePanelFormRow(
            left: AppTextField(
              controller: _policyNoController,
              label: 'Policy No *',
              validator: (v) => Validators.required(v, fieldName: 'Policy No'),
            ),
            right: AppTextField(
              controller: _insurerNameController,
              label: 'Insurer Name *',
              validator: (v) => Validators.required(v, fieldName: 'Insurer Name'),
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: AppTextField(
              controller: _insurerBranchController,
              label: 'Insurer Branch',
            ),
            right: AppTextField(
              controller: _insurerContactController,
              label: 'Insurer Contact',
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: AppTextField(
              controller: _insurerPhoneController,
              label: 'Insurer Phone',
            ),
            right: AppTextField(
              controller: _insurerEmailController,
              label: 'Insurer Email',
              keyboardType: TextInputType.emailAddress,
              validator: Validators.optionalEmail,
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: AppSearchableDropdown<String>(
              label: 'Policy Type',
              value: _policyType,
              searchHint: 'Search policy type...',
              options: assetOptionDropdowns(options.policyTypes),
              enabled: options.policyTypes.isNotEmpty,
              onChanged: (v) {
                if (v != null) setState(() => _policyType = v);
              },
            ),
            right: AppTextField(
              controller: _sumInsuredController,
              label: 'Sum Insured',
              keyboardType: const TextInputType.numberWithOptions(decimal: true),
              inputFormatters: CurrencyFormatter.amountInput,
              validator: (v) => Validators.optionalNonNegativeDouble(
                v,
                fieldName: 'Sum Insured',
              ),
            ),
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _annualPremiumController,
            label: 'Annual Premium',
            keyboardType: const TextInputType.numberWithOptions(decimal: true),
            inputFormatters: CurrencyFormatter.amountInput,
            validator: (v) => Validators.optionalNonNegativeDouble(
              v,
              fieldName: 'Annual Premium',
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: _SidePanelDateField(
              label: 'Start Date',
              isRequired: true,
              value: _startDate,
              onPick: () => _pickDate(
                current: _startDate,
                onPicked: _onStartDatePicked,
              ),
            ),
            right: _SidePanelDateField(
              label: 'End Date',
              isRequired: true,
              value: _endDate,
              onPick: () => _pickDate(
                current: _endDate,
                firstDate: _startDate ?? DateTime(2000),
                onPicked: (date) => _endDate = date,
              ),
            ),
          ),
          const SizedBox(height: 12),
          SidePanelFormRow(
            left: _SidePanelDateField(
              label: 'Renewal Date',
              value: _renewalDate,
              onPick: () => _pickDate(
                current: _renewalDate,
                onPicked: (date) => _renewalDate = date,
              ),
            ),
            right: _SidePanelDateField(
              label: 'Premium Paid Date',
              value: _premiumPaidDate,
              onPick: () => _pickDate(
                current: _premiumPaidDate,
                onPicked: (date) => _premiumPaidDate = date,
              ),
            ),
          ),
          const SizedBox(height: 8),
          AppFormToggleField(
            label: 'Auto Renewal',
            value: _isAutoRenewal,
            onChanged: (value) => setState(() => _isAutoRenewal = value),
          ),
          AppFormToggleField(
            label: 'Premium Paid',
            value: _premiumPaid,
            onChanged: (value) => setState(() => _premiumPaid = value),
          ),
          AppFormToggleField(
            label: 'Active',
            value: _isActive,
            onChanged: (value) => setState(() => _isActive = value),
          ),
          const SizedBox(height: 12),
          AppTextField(
            controller: _remarksController,
            label: 'Remarks',
            maxLines: 3,
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    if (widget.isEdit) {
      final policyAsync = ref.watch(
        insurancePolicyFormProvider((
          assetId: widget.assetId,
          policyId: widget.policyId!,
        )),
      );
      return policyAsync.when(
        loading: () => SidePanelScaffold(
          title: 'Edit Insurance Policy',
          footer: _panelFooter(
            context,
            isSubmitting: true,
            saveLabel: 'Update Insurance Policy',
            onSave: () {},
          ),
          child: const Center(child: CircularProgressIndicator()),
        ),
        error: (error, _) => SidePanelScaffold(
          title: 'Edit Insurance Policy',
          child: Center(child: Text(error.toString())),
        ),
        data: (policy) {
          _populateFromPolicy(policy);
          return SidePanelScaffold(
            title: 'Edit Insurance Policy',
            footer: _panelFooter(
              context,
              isSubmitting: _isSubmitting,
              saveLabel: 'Update Insurance Policy',
              onSave: _save,
            ),
            child: _buildForm(),
          );
        },
      );
    }

    return SidePanelScaffold(
      title: 'Add Insurance Policy',
      footer: _panelFooter(
        context,
        isSubmitting: _isSubmitting,
        saveLabel: 'Save Insurance Policy',
        onSave: _save,
      ),
      child: _buildForm(),
    );
  }
}

class TransferAssetPanel extends ConsumerStatefulWidget {
  const TransferAssetPanel({super.key, required this.assetId});

  final String assetId;

  @override
  ConsumerState<TransferAssetPanel> createState() => _TransferAssetPanelState();
}

class _TransferAssetPanelState extends ConsumerState<TransferAssetPanel> {
  final _formKey = GlobalKey<FormState>();
  final _reasonController = TextEditingController();
  DateTime _transferDate = DateTime.now();
  int? _toLocationId;
  int? _toUserId;
  bool _isSubmitting = false;

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

  Future<void> _pickDate() async {
    final picked = await showAppDatePopup(
      context: context,
      initialDate: _transferDate,
      firstDate: DateTime(2000),
      lastDate: DateTime(2100),
      helpText: 'Transfer date',
    );
    if (picked != null) {
      setState(() => _transferDate = picked);
    }
  }

  Future<void> _save() async {
    if (!_formKey.currentState!.validate()) return;

    final hasDestination = _toLocationId != null || _toUserId != null;
    if (!hasDestination) {
      showSidePanelSnackBar(
        context,
        'Choose at least one destination field',
      );
      return;
    }

    setState(() => _isSubmitting = true);
    try {
      await ref.read(assetDetailProvider(widget.assetId).notifier).transferAsset({
        'transfer_date': DateFormatter.toApiDate(_transferDate),
        if (_toLocationId != null) 'to_location_id': _toLocationId,
        if (_toUserId != null) 'to_user_id': _toUserId,
        'reason': _reasonController.text.trim(),
      });
      if (mounted) {
        Navigator.of(context, rootNavigator: true).pop(true);
      }
    } catch (e) {
      if (mounted) {
        showSidePanelApiError(context, e);
      }
    } finally {
      if (mounted) setState(() => _isSubmitting = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final lookupsAsync = ref.watch(assetFormLookupsProvider);
    return SidePanelScaffold(
      title: 'Transfer Asset',
      footer: _panelFooter(
        context,
        isSubmitting: _isSubmitting,
        saveLabel: 'Transfer',
        onSave: _save,
      ),
      child: lookupsAsync.when(
        loading: () => const Center(child: CircularProgressIndicator()),
        error: (error, _) => Center(child: Text(error.toString())),
        data: (lookups) => Form(
          key: _formKey,
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              _SidePanelDateField(
                label: 'Transfer Date',
                isRequired: true,
                value: _transferDate,
                onPick: _pickDate,
              ),
              const SizedBox(height: 12),
              AppSearchableDropdown<int>(
                label: 'To Location',
                value: _toLocationId,
                searchHint: 'Search plant or warehouse...',
                options: lookups.locations
                    .map((option) {
                      final id = int.tryParse(option.id);
                      if (id == null) return null;
                      return AppDropdownOption(value: id, label: option.name);
                    })
                    .whereType<AppDropdownOption<int>>()
                    .toList(),
                onChanged: (v) => setState(() => _toLocationId = v),
              ),
              const SizedBox(height: 12),
              AppSearchableDropdown<int>(
                label: 'To User',
                value: _toUserId,
                searchHint: 'Search user...',
                options: lookups.users
                    .map((option) {
                      final id = int.tryParse(option.id);
                      if (id == null) return null;
                      return AppDropdownOption(value: id, label: option.name);
                    })
                    .whereType<AppDropdownOption<int>>()
                    .toList(),
                onChanged: (v) => setState(() => _toUserId = v),
              ),
              const SizedBox(height: 12),
              AppTextField(
                controller: _reasonController,
                label: 'Reason *',
                maxLines: 3,
                validator: (v) => Validators.required(v, fieldName: 'Reason'),
              ),
            ],
          ),
        ),
      ),
    );
  }
}

class _TransferHistoryEntry extends StatelessWidget {
  const _TransferHistoryEntry({required this.item});

  final AssetTransferHistoryModel item;

  DateTime? _resolvedTransferDateTime() {
    final transferDate = item.transferDate?.toLocal();
    final createdAt = item.createdAt?.toLocal();
    if (transferDate == null) return createdAt;
    if (createdAt == null) return transferDate;
    return DateTime(
      transferDate.year,
      transferDate.month,
      transferDate.day,
      createdAt.hour,
      createdAt.minute,
    );
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final resolvedDateTime = _resolvedTransferDateTime();
    final transferDate = resolvedDateTime != null
        ? DateFormatter.displayDateTime(resolvedDateTime)
        : '—';
    final reason = item.reason?.trim();
    final showReason = reason != null && reason.isNotEmpty && reason.toLowerCase() != 'nil';

    return AppCard(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Icon(
                  Icons.swap_horiz_rounded,
                  size: 18,
                  color: theme.colorScheme.primary,
                ),
                const SizedBox(width: 8),
                Text(
                  transferDate,
                  style: theme.textTheme.titleSmall?.copyWith(
                    fontWeight: FontWeight.w700,
                  ),
                ),
              ],
            ),
            const SizedBox(height: 16),
            _TransferFromToGrid(
              fromLocation: item.fromLocationName,
              fromUser: item.fromUserName,
              toLocation: item.toLocationName,
              toUser: item.toUserName,
            ),
            if (showReason) ...[
              const SizedBox(height: 16),
              Divider(
                height: 1,
                color: theme.colorScheme.outline.withValues(alpha: 0.2),
              ),
              const SizedBox(height: 12),
              Text(
                'Reason',
                style: theme.textTheme.labelSmall?.copyWith(
                  fontWeight: FontWeight.w700,
                  letterSpacing: 0.6,
                  color: theme.colorScheme.onSurfaceVariant,
                ),
              ),
              const SizedBox(height: 4),
              Text(
                reason,
                style: theme.textTheme.bodySmall?.copyWith(
                  color: theme.colorScheme.onSurfaceVariant,
                ),
              ),
            ],
          ],
        ),
      ),
    );
  }
}

class _TransferFromToGrid extends StatelessWidget {
  const _TransferFromToGrid({
    this.fromLocation,
    this.fromUser,
    this.toLocation,
    this.toUser,
  });

  final String? fromLocation;
  final String? fromUser;
  final String? toLocation;
  final String? toUser;

  static const _arrowWidth = 34.0;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final labelStyle = theme.textTheme.labelSmall?.copyWith(
      fontWeight: FontWeight.w700,
      letterSpacing: 0.6,
      color: theme.colorScheme.onSurfaceVariant,
    );

    return Column(
      crossAxisAlignment: CrossAxisAlignment.stretch,
      children: [
        Row(
          children: [
            Expanded(child: Text('From', style: labelStyle)),
            const SizedBox(width: _arrowWidth),
            Expanded(child: Text('To', style: labelStyle)),
          ],
        ),
        const SizedBox(height: 8),
        Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Expanded(
              child: _TransferLocationRow(
                icon: Icons.place_outlined,
                value: fromLocation,
              ),
            ),
            SizedBox(
              width: _arrowWidth,
              child: Padding(
                padding: const EdgeInsets.only(top: 1),
                child: Icon(
                  Icons.arrow_forward_rounded,
                  size: 18,
                  color: theme.colorScheme.outline,
                ),
              ),
            ),
            Expanded(
              child: _TransferLocationRow(
                icon: Icons.place_outlined,
                value: toLocation,
              ),
            ),
          ],
        ),
        Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Expanded(
              child: _TransferLocationRow(
                icon: Icons.person_outline,
                value: fromUser,
              ),
            ),
            const SizedBox(width: _arrowWidth),
            Expanded(
              child: _TransferLocationRow(
                icon: Icons.person_outline,
                value: toUser,
              ),
            ),
          ],
        ),
      ],
    );
  }
}

class _TransferLocationRow extends StatelessWidget {
  const _TransferLocationRow({
    required this.icon,
    this.value,
  });

  final IconData icon;
  final String? value;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final display = value?.trim().isNotEmpty == true ? value!.trim() : '—';

    return Padding(
      padding: const EdgeInsets.only(bottom: 6),
      child: Row(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Icon(
            icon,
            size: 14,
            color: theme.colorScheme.onSurfaceVariant,
          ),
          const SizedBox(width: 6),
          Expanded(
            child: Text(
              display,
              style: theme.textTheme.bodySmall?.copyWith(
                color: display == '—'
                    ? theme.colorScheme.onSurfaceVariant
                    : theme.colorScheme.onSurface,
              ),
            ),
          ),
        ],
      ),
    );
  }
}

class TransferHistoryPanel extends ConsumerWidget {
  const TransferHistoryPanel({super.key, required this.assetId});

  final String assetId;

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final historyAsync = ref.watch(transferHistoryProvider(assetId));
    return SidePanelScaffold(
      title: 'Transfer History',
      child: historyAsync.when(
        loading: () => const Center(child: CircularProgressIndicator()),
        error: (error, _) => ErrorView(
          message: error is Failure
              ? error.message
              : 'Unable to load transfer history',
          onRetry: () => ref.invalidate(transferHistoryProvider(assetId)),
        ),
        data: (history) {
          if (history.isEmpty) {
            return const AppEmptyState(
              title: 'No transfer history',
              description: 'Transfers for this asset will appear here.',
              icon: Icons.swap_horiz_outlined,
            );
          }

          final theme = Theme.of(context);
          return Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(
                '${history.length} transfer${history.length == 1 ? '' : 's'}',
                style: theme.textTheme.bodySmall?.copyWith(
                  color: theme.colorScheme.onSurfaceVariant,
                  fontWeight: FontWeight.w600,
                ),
              ),
              const SizedBox(height: 16),
              for (var index = 0; index < history.length; index++) ...[
                if (index > 0) const SizedBox(height: 12),
                _TransferHistoryEntry(item: history[index]),
              ],
            ],
          );
        },
      ),
    );
  }
}

Widget _panelFooter(
  BuildContext context, {
  required bool isSubmitting,
  required String saveLabel,
  required VoidCallback onSave,
}) {
  return Row(
    mainAxisAlignment: MainAxisAlignment.end,
    children: [
      OutlinedButton(
        onPressed: isSubmitting
            ? null
            : () => Navigator.of(context, rootNavigator: true).pop(),
        child: const Text('Cancel'),
      ),
      const SizedBox(width: 12),
      AppButton(
        label: saveLabel,
        expand: false,
        icon: Icons.check,
        isLoading: isSubmitting,
        onPressed: isSubmitting ? null : onSave,
      ),
    ],
  );
}

class _SidePanelDateField extends StatefulWidget {
  const _SidePanelDateField({
    required this.label,
    required this.value,
    required this.onPick,
    this.isRequired = false,
  });

  final String label;
  final DateTime? value;
  final VoidCallback onPick;
  final bool isRequired;

  @override
  State<_SidePanelDateField> createState() => _SidePanelDateFieldState();
}

class _SidePanelDateFieldState extends State<_SidePanelDateField> {
  late final TextEditingController _controller;

  String get _displayText =>
      widget.value != null ? DateFormatter.displayDate(widget.value) : '';

  String get _labelText =>
      widget.isRequired ? '${widget.label} *' : widget.label;

  @override
  void initState() {
    super.initState();
    _controller = TextEditingController(text: _displayText);
  }

  @override
  void didUpdateWidget(covariant _SidePanelDateField oldWidget) {
    super.didUpdateWidget(oldWidget);
    final text = _displayText;
    if (_controller.text != text) {
      _controller.text = text;
    }
  }

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

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.only(top: 8),
      child: TextFormField(
        readOnly: true,
        onTap: widget.onPick,
        controller: _controller,
        decoration: InputDecoration(
          labelText: _labelText,
          hintText: 'Select date',
          floatingLabelBehavior: FloatingLabelBehavior.always,
          suffixIcon: const Icon(Icons.calendar_today_outlined, size: 20),
        ),
      ),
    );
  }
}