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

import '../labels.dart';
import '../models/models.dart';
import '../services/auth_controller.dart';
import '../ui/feedback.dart';

class StockFormScreen extends StatefulWidget {
  const StockFormScreen({super.key, required this.dealers});

  final List<Dealer> dealers;

  @override
  State<StockFormScreen> createState() => _StockFormScreenState();
}

class _StockFormScreenState extends State<StockFormScreen> {
  final _chassis = TextEditingController();
  final _engine = TextEditingController();
  final _color = TextEditingController();
  String _model = modelOptions.first;
  String? _dealerId;
  DateTime _received = DateTime.now();
  bool _saving = false;

  @override
  void initState() {
    super.initState();
    final user = context.read<AuthController>().user;
    if (user?.role == 'dealer') {
      _dealerId = user?.dealerId ?? (widget.dealers.isNotEmpty ? widget.dealers.first.id : null);
    } else if (widget.dealers.length == 1) {
      _dealerId = widget.dealers.first.id;
    }
  }

  @override
  void dispose() {
    _chassis.dispose();
    _engine.dispose();
    _color.dispose();
    super.dispose();
  }

  Future<void> _save() async {
    if (_dealerId == null) {
      showError(context, 'Choose a dealer');
      return;
    }
    setState(() => _saving = true);
    try {
      await context.read<AuthController>().api.createStock({
        'chassisNumber': _chassis.text.trim(),
        'engineNumber': _engine.text.trim(),
        'model': _model,
        'color': _color.text.trim(),
        'currentDealerId': _dealerId,
        'dateReceived': _received.toUtc().toIso8601String(),
      });
      if (mounted) Navigator.pop(context, true);
    } catch (error) {
      if (mounted) showError(context, error);
    } finally {
      if (mounted) setState(() => _saving = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    final lockedToOwnDealer = context.watch<AuthController>().user?.role == 'dealer';
    Dealer? ownDealer;
    for (final dealer in widget.dealers) {
      if (dealer.id == _dealerId) {
        ownDealer = dealer;
        break;
      }
    }
    return Scaffold(
      appBar: AppBar(title: const Text('Add stock')),
      body: ListView(
        padding: const EdgeInsets.all(16),
        children: [
          TextField(controller: _chassis, decoration: const InputDecoration(labelText: 'Chassis number')),
          const SizedBox(height: 12),
          TextField(controller: _engine, decoration: const InputDecoration(labelText: 'Engine number')),
          const SizedBox(height: 12),
          DropdownButtonFormField<String>(
            initialValue: _model,
            decoration: const InputDecoration(labelText: 'Model'),
            items: [
              for (final model in modelOptions)
                DropdownMenuItem(value: model, child: Text(modelLabel(model))),
            ],
            onChanged: (value) {
              if (value != null) setState(() => _model = value);
            },
          ),
          const SizedBox(height: 12),
          TextField(controller: _color, decoration: const InputDecoration(labelText: 'Color')),
          const SizedBox(height: 12),
          if (lockedToOwnDealer)
            InputDecorator(
              decoration: const InputDecoration(labelText: 'Dealer'),
              child: Text(
                ownDealer == null ? 'Your dealership' : '${ownDealer.name} (${ownDealer.code})',
              ),
            )
          else
            DropdownButtonFormField<String>(
              initialValue: _dealerId,
              decoration: const InputDecoration(labelText: 'Dealer'),
              items: [
                for (final dealer in widget.dealers)
                  DropdownMenuItem(value: dealer.id, child: Text('${dealer.name} (${dealer.code})')),
              ],
              onChanged: (value) => setState(() => _dealerId = value),
            ),
          const SizedBox(height: 12),
          ListTile(
            contentPadding: EdgeInsets.zero,
            title: const Text('Received date'),
            subtitle: Text(_received.toLocal().toString().split(' ').first),
            trailing: const Icon(Icons.calendar_today),
            onTap: () async {
              final picked = await showDatePicker(
                context: context,
                initialDate: _received,
                firstDate: DateTime(2000),
                lastDate: DateTime.now().add(const Duration(days: 1)),
              );
              if (picked != null) setState(() => _received = picked);
            },
          ),
          const SizedBox(height: 16),
          FilledButton(
            onPressed: _saving ? null : _save,
            child: Text(_saving ? 'Saving' : 'Save stock'),
          ),
        ],
      ),
    );
  }
}