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

import '../models/saham_transaksi.dart';
import '../services/stock_service.dart';

class AddTransaksiScreen extends StatefulWidget {
  const AddTransaksiScreen({super.key, required this.service});
  final StockService service;

  @override
  State<AddTransaksiScreen> createState() => _AddTransaksiScreenState();
}

class _AddTransaksiScreenState extends State<AddTransaksiScreen> {
  final _tanggal = TextEditingController(
      text: DateFormat('yyyy-MM-dd').format(DateTime.now()));
  final _volume = TextEditingController();
  final _harga = TextEditingController();
  final _fee = TextEditingController(text: '0');

  late Future<List<Saham>> _sahamFut;
  int? _sahamId;
  bool _isBuy = true;
  bool _busy = false;
  String? _err;

  @override
  void initState() {
    super.initState();
    _sahamFut = widget.service.listSaham();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Catat Transaksi')),
      body: Padding(
        padding: const EdgeInsets.all(16),
        child: ListView(
          children: [
            SegmentedButton<bool>(
              segments: const [
                ButtonSegment(value: true, label: Text('Beli'), icon: Icon(Icons.add)),
                ButtonSegment(value: false, label: Text('Jual'), icon: Icon(Icons.remove)),
              ],
              selected: {_isBuy},
              onSelectionChanged: (s) => setState(() => _isBuy = s.first),
            ),
            const SizedBox(height: 16),
            TextField(controller: _tanggal,
                decoration: const InputDecoration(labelText: 'Tanggal (YYYY-MM-DD)',
                    prefixIcon: Icon(Icons.calendar_today))),
            const SizedBox(height: 12),
            FutureBuilder<List<Saham>>(
              future: _sahamFut,
              builder: (context, snap) {
                if (snap.connectionState != ConnectionState.done) {
                  return const ListTile(
                      leading: SizedBox(width:18,height:18,child:CircularProgressIndicator(strokeWidth:2)),
                      title: Text('Memuat saham...'));
                }
                if (snap.hasError) {
                  return Text('Error saham: ${snap.error}', style: const TextStyle(color: Colors.red));
                }
                final saham = snap.data ?? [];
                return DropdownButtonFormField<int>(
                  initialValue: _sahamId,
                  decoration: const InputDecoration(labelText: 'Pilih Saham',
                      prefixIcon: Icon(Icons.business)),
                  items: [
                    for (final s in saham)
                      DropdownMenuItem(value: s.id, child: Text('${s.kode} — ${s.perusahaan ?? ''}')),
                  ],
                  onChanged: (v) => setState(() => _sahamId = v),
                );
              },
            ),
            const SizedBox(height: 12),
            TextField(controller: _volume, keyboardType: TextInputType.number,
                decoration: const InputDecoration(labelText: 'Jumlah Lembar', prefixIcon: Icon(Icons.numbers))),
            const SizedBox(height: 12),
            TextField(controller: _harga, keyboardType: const TextInputType.numberWithOptions(decimal: true),
                decoration: const InputDecoration(labelText: 'Harga per Lembar (Rp)', prefixIcon: Icon(Icons.attach_money))),
            const SizedBox(height: 12),
            TextField(controller: _fee, keyboardType: const TextInputType.numberWithOptions(decimal: true),
                decoration: const InputDecoration(labelText: 'Biaya / Fee (Rp)', prefixIcon: Icon(Icons.payments))),
            if (_err != null)
              Padding(padding: const EdgeInsets.only(top: 8),
                  child: Text(_err!, style: const TextStyle(color: Colors.red))),
            const SizedBox(height: 20),
            FilledButton.icon(
              onPressed: _busy ? null : _save,
              icon: _busy ? const SizedBox(width:18,height:18,child:CircularProgressIndicator(strokeWidth:2))
                          : const Icon(Icons.save),
              label: const Text('Simpan'),
            ),
          ],
        ),
      ),
    );
  }

  Future<void> _save() async {
    setState(() { _busy = true; _err = null; });
    try {
      final date = _tanggal.text.trim();
      final vol = int.tryParse(_volume.text.trim()) ?? 0;
      final harga = double.tryParse(_harga.text.replaceAll('.', '').replaceAll(',', '.')) ?? 0;
      final feeC = double.tryParse(_fee.text.trim().isEmpty ? '0' : _fee.text.trim()) ?? 0;
      if (_sahamId == null) throw Exception('Pilih saham dulu');
      if (vol <= 0) throw Exception('Volume harus > 0');
      if (harga <= 0) throw Exception('Harga harus > 0');
      if (!date.contains('-')) throw Exception('Format tanggal salah');

      await widget.service.addTransaksi(
          sahamId: _sahamId!, tipe: _isBuy ? 'buy' : 'sell',
          volume: vol, harga: harga, fee: feeC, tanggal: date);
      if (!mounted) return;
      Navigator.pop(context, true);
    } catch (e) {
      if (!mounted) return;
      setState(() { _busy = false; _err = e.toString().replaceFirst('Exception: ', ''); });
    }
  }
}