saat-app/flutter/lib/edit_saham_screen.dart

import 'package:flutter/material.dart';

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

class EditSahamScreen extends StatefulWidget {
  const EditSahamScreen({super.key, required this.service, this.saham});
  final StockService service;
  final Saham? saham; // null = tambah baru; ada = edit
  @override
  State<EditSahamScreen> createState() => _EditSahamScreenState();
}

class _EditSahamScreenState extends State<EditSahamScreen> {
  final _kode = TextEditingController();
  final _perusahaan = TextEditingController();
  final _sektor = TextEditingController();
  bool _busy = false;
  String? _error;

  @override
  void initState() {
    super.initState();
    final s = widget.saham;
    if (s != null) {
      _kode.text = s.kode;
      _perusahaan.text = s.perusahaan ?? '';
      _sektor.text = s.sektor ?? '';
    } else {
      _sektor.text = 'Financial';
    }
  }

  @override
  Widget build(BuildContext context) {
    final isEdit = widget.saham != null;
    return Scaffold(
      appBar: AppBar(title: Text(isEdit ? 'Edit Saham' : 'Tambah Saham')),
      body: Padding(
        padding: const EdgeInsets.all(16),
        child: ListView(
          children: [
            TextField(
              controller: _kode,
              enabled: !isEdit, // kode tidak boleh diubah saat edit
              decoration: const InputDecoration(
                  labelText: 'Kode Saham (Ticker)',
                  hintText: 'misal: BBRI, UNVR, TLKM',
                  prefixIcon: Icon(Icons.business)),
            ),
            const SizedBox(height: 12),
            TextField(
              controller: _perusahaan,
              decoration: const InputDecoration(
                  labelText: 'Nama Perusahaan / Emiten',
                  prefixIcon: Icon(Icons.apartment)),
            ),
            const SizedBox(height: 12),
            TextField(
              controller: _sektor,
              decoration: const InputDecoration(
                  labelText: 'Sektor', prefixIcon: Icon(Icons.category)),
            ),
            if (_error != null)
              Padding(
                padding: const EdgeInsets.only(top: 8),
                child: Text(_error!, 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;
      _error = null;
    });
    try {
      final kode = _kode.text.trim().toUpperCase();
      if (kode.isEmpty) throw Exception('Kode saham wajib diisi');

      if (widget.saham == null) {
        await widget.service.addSaham(
          kode: kode,
          perusahaan: _perusahaan.text.trim(),
          sektor: _sektor.text.trim(),
        );
      } else {
        await widget.service.updateSaham(widget.saham!.id,
          perusahaan: _perusahaan.text.trim(),
          sektor: _sektor.text.trim(),
        );
      }
      if (!mounted) return;
      Navigator.pop(context, true);
    } catch (e) {
      if (!mounted) return;
      setState(() {
        _busy = false;
        _error = e.toString().replaceFirst('Exception: ', '');
      });
    }
  }
}