inv/gemi_invoice/lib/main.dart

// version: 1.2.0 (Share-ready, Bottom-8 Hash, Template Edition)
import 'dart:io';
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart' show rootBundle;

// パッケージ
import 'package:flutter_contacts/flutter_contacts.dart';
import 'package:permission_handler/permission_handler.dart';
import 'package:share_plus/share_plus.dart'; // 共有機能
import 'package:pdf/widgets.dart' as pw;
import 'package:path_provider/path_provider.dart';
import 'package:crypto/crypto.dart';
import 'package:intl/intl.dart';

void main() => runApp(const MaterialApp(home: InvoiceApp()));

class InvoiceApp extends StatefulWidget {
  const InvoiceApp({super.key});
  @override
  State<InvoiceApp> createState() => _InvoiceAppState();
}

class _InvoiceAppState extends State<InvoiceApp> {
  final _clientController = TextEditingController(text: "佐々木製作所");
  final _amountController = TextEditingController(text: "250000");
  String _status = "内容を入力してPDFを発行してください";

  // 【設定】ファイル名のフォーマット定数
  static const String filenameTemplate = "{date}(請求){name}_{amount}円_{hash}.pdf";

  // --- 電話帳から選ぶ ---
  Future<void> _pickContact() async {
    try {
      var status = await Permission.contacts.request();
      if (status.isGranted) {
        final contact = await FlutterContacts.openExternalPick();
        if (contact != null) {
          final fullContact = await FlutterContacts.getContact(contact.id);
          setState(() {
            String name = fullContact?.displayName ?? "名称不明";
            _clientController.text = name;
            _status = "連絡先から「$name」を読み込みました";
          });
        }
      } else if (status.isPermanentlyDenied) {
        openAppSettings();
      }
    } catch (e) {
      setState(() => _status = "エラー: $e");
    }
  }

  // --- PDF発行 & 共有ロジック ---
  Future<void> _generateInvoice() async {
    final pdf = pw.Document();

    // フォント読み込み
    final fontData = await rootBundle.load("assets/fonts/ipaexg.ttf");
    final ttf = pw.Font.ttf(fontData);
    final myTheme = pw.ThemeData.withFont(base: ttf, bold: ttf);

    final clientName = _clientController.text;
    final int unitPrice = int.tryParse(_amountController.text) ?? 0;
    final int tax = (unitPrice * 0.1).floor();
    final int total = unitPrice + tax;

    final now = DateTime.now();
    final dateStr = DateFormat('yyyy/MM/dd HH:mm').format(now);
    final dateFileStr = DateFormat('yyyyMMdd').format(now);
    final amountFormatter = NumberFormat("#,###");

    // PDFレイアウト作成
    pdf.addPage(
      pw.Page(
        theme: myTheme,
        build: (context) => pw.Column(
          crossAxisAlignment: pw.CrossAxisAlignment.start,
          children: [
            pw.Text("請求書 (Invoice)", style: pw.TextStyle(fontSize: 30)),
            pw.Divider(),
            pw.Text("宛名: $clientName 様"),
            pw.Text("日付: $dateStr"),
            pw.SizedBox(height: 20),
            pw.Text("単価（税抜）: ${amountFormatter.format(unitPrice)} 円"),
            pw.Text("消費税 (10%): ${amountFormatter.format(tax)} 円"),
            pw.Text("合計金額（税込）: ${amountFormatter.format(total)} 円",
              style: pw.TextStyle(fontWeight: pw.FontWeight.bold, fontSize: 20)),
            pw.SizedBox(height: 40),
            pw.Text("※本証憑はSHA-256ハッシュにより改ざん耐性を担保しています。"),
          ],
        ),
      ),
    );

    final Uint8List bytes = await pdf.save();

    // SHA-256ハッシュ計算（末尾8文字）
    final String fullHash = sha256.convert(bytes).toString();
    final String hash = fullHash.substring(fullHash.length - 8);

    // ファイル名生成
    String fileName = filenameTemplate
        .replaceAll("{date}", dateFileStr)
        .replaceAll("{name}", clientName)
        .replaceAll("{amount}", amountFormatter.format(total))
        .replaceAll("{hash}", hash);

    // 一時保存
    final directory = await getTemporaryDirectory(); // 共有用なので一時フォルダでOK
    final file = File("${directory.path}/$fileName");
    await file.writeAsBytes(bytes);

    // 【新機能】共有メニューを起動！
    await Share.shareXFiles(
      [XFile(file.path)],
      text: '請求書を送付します: $fileName',
      subject: '請求書: $clientName 様'
    );

    setState(() {
      _status = "【発行＆共有】\n$fileName\nHASH: $hash";
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("現場のじぇみエモン請求書 V1.2"),
        backgroundColor: Colors.blueGrey,
      ),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: SingleChildScrollView(
          child: Column(children: [
            Row(children: [
              Expanded(
                child: TextField(
                  controller: _clientController,
                  decoration: const InputDecoration(labelText: "取引先名", border: OutlineInputBorder())
                ),
              ),
              const SizedBox(width: 8),
              IconButton(
                icon: const Icon(Icons.contact_mail, color: Colors.blue, size: 36),
                onPressed: _pickContact,
              ),
            ]),
            const SizedBox(height: 16),
            TextField(
              controller: _amountController,
              keyboardType: TextInputType.number,
              decoration: const InputDecoration(labelText: "単価 (税抜)", border: OutlineInputBorder())
            ),
            const SizedBox(height: 24),
            ElevatedButton.icon(
              onPressed: _generateInvoice,
              icon: const Icon(Icons.send),
              label: const Text("PDF発行 & 共有 (Nextcloudへ)"),
              style: ElevatedButton.styleFrom(
                minimumSize: const Size(double.infinity, 60),
                backgroundColor: Colors.blueAccent,
                foregroundColor: Colors.white,
              ),
            ),
            const SizedBox(height: 24),
            Container(
              width: double.infinity,
              padding: const EdgeInsets.all(12),
              color: Colors.grey[200],
              child: SelectableText(_status, style: const TextStyle(fontFamily: 'monospace')),
            ),
          ]),
        ),
      ),
    );
  }
}