// lib/screens/invoice_input_screen.dart
import 'package:flutter/material.dart';
import 'package:uuid/uuid.dart';
import '../models/customer_model.dart';
import '../models/invoice_models.dart';
import '../services/pdf_generator.dart';
import '../services/invoice_repository.dart';
import '../services/master_repository.dart';
import 'customer_picker_modal.dart';

/// 帳票の初期入力（ヘッダー部分）を管理するウィジェット
class InvoiceInputForm extends StatefulWidget {
  final Function(Invoice invoice, String filePath) onInvoiceGenerated;

  const InvoiceInputForm({
    Key? key,
    required this.onInvoiceGenerated,
  }) : super(key: key);

  @override
  State<InvoiceInputForm> createState() => _InvoiceInputFormState();
}

class _InvoiceInputFormState extends State<InvoiceInputForm> {
  final _clientController = TextEditingController();
  final _amountController = TextEditingController(text: "250000");
  final _invoiceRepository = InvoiceRepository();
  final _masterRepository = MasterRepository();

  DocumentType _selectedType = DocumentType.invoice; // デフォルトは請求書
  String _status = "取引先を選択してPDFを生成してください";
  List<Customer> _customerBuffer = [];
  Customer? _selectedCustomer;
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    _loadInitialData();
  }

  /// 初期データの読み込み
  Future<void> _loadInitialData() async {
    setState(() => _isLoading = true);

    final savedCustomers = await _masterRepository.loadCustomers();

    setState(() {
      _customerBuffer = savedCustomers;
      if (_customerBuffer.isNotEmpty) {
        _selectedCustomer = _customerBuffer.first;
        _clientController.text = _selectedCustomer!.formalName;
      }
      _isLoading = false;
    });

    _invoiceRepository.cleanupOrphanedPdfs().then((count) {
      if (count > 0) {
        debugPrint('Cleaned up $count orphaned PDF files.');
      }
    });
  }

  @override
  void dispose() {
    _clientController.dispose();
    _amountController.dispose();
    super.dispose();
  }

  /// 顧客選択モーダルを開く
  Future<void> _openCustomerPicker() async {
    setState(() => _status = "顧客マスターを開いています...");

    await showModalBottomSheet<void>(
      context: context,
      isScrollControlled: true,
      backgroundColor: Colors.transparent,
      builder: (context) => FractionallySizedBox(
        heightFactor: 0.9,
        child: CustomerPickerModal(
          existingCustomers: _customerBuffer,
          onCustomerSelected: (customer) async {
            setState(() {
              int index = _customerBuffer.indexWhere((c) => c.id == customer.id);
              if (index != -1) {
                _customerBuffer[index] = customer;
              } else {
                _customerBuffer.add(customer);
              }

              _selectedCustomer = customer;
              _clientController.text = customer.formalName;
              _status = "「${customer.formalName}」を選択しました";
            });

            await _masterRepository.saveCustomers(_customerBuffer);
            if (mounted) Navigator.pop(context);
          },
          onCustomerDeleted: (customer) async {
            setState(() {
              _customerBuffer.removeWhere((c) => c.id == customer.id);
              if (_selectedCustomer?.id == customer.id) {
                _selectedCustomer = null;
                _clientController.clear();
              }
            });
            await _masterRepository.saveCustomers(_customerBuffer);
          },
        ),
      ),
    );
  }

  /// 初期PDFを生成して詳細画面へ進む
  Future<void> _handleInitialGenerate() async {
    if (_selectedCustomer == null) {
      setState(() => _status = "取引先を選択してください");
      return;
    }

    final unitPrice = int.tryParse(_amountController.text) ?? 0;

    final initialItems = [
      InvoiceItem(
        description: "${_selectedType.label}分",
        quantity: 1,
        unitPrice: unitPrice,
      )
    ];

    final invoice = Invoice(
      customer: _selectedCustomer!,
      date: DateTime.now(),
      items: initialItems,
      type: _selectedType,
    );

    setState(() => _status = "${_selectedType.label}を生成中...");
    final path = await generateInvoicePdf(invoice);

    if (path != null) {
      final updatedInvoice = invoice.copyWith(filePath: path);
      await _invoiceRepository.saveInvoice(updatedInvoice);
      widget.onInvoiceGenerated(updatedInvoice, path);
      setState(() => _status = "${_selectedType.label}を生成しDBに登録しました。");
    } else {
      setState(() => _status = "PDFの生成に失敗しました");
    }
  }

  @override
  Widget build(BuildContext context) {
    if (_isLoading) {
      return const Center(child: CircularProgressIndicator());
    }

    return Padding(
      padding: const EdgeInsets.all(16.0),
      child: SingleChildScrollView(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            const Text(
              "帳票の種類を選択",
              style: TextStyle(fontWeight: FontWeight.bold, color: Colors.blueGrey),
            ),
            const SizedBox(height: 8),
            Wrap(
              spacing: 8.0,
              children: DocumentType.values.map((type) {
                return ChoiceChip(
                  label: Text(type.label),
                  selected: _selectedType == type,
                  onSelected: (selected) {
                    if (selected) {
                      setState(() => _selectedType = type);
                    }
                  },
                  selectedColor: Colors.indigo.shade100,
                );
              }).toList(),
            ),
            const SizedBox(height: 24),
            const Text(
              "宛先と基本金額の設定",
              style: TextStyle(fontWeight: FontWeight.bold, color: Colors.blueGrey),
            ),
            const SizedBox(height: 12),
            Row(children: [
              Expanded(
                child: TextField(
                  controller: _clientController,
                  readOnly: true,
                  onTap: _openCustomerPicker,
                  decoration: const InputDecoration(
                    labelText: "取引先名 (タップして選択)",
                    hintText: "マスターから選択または電話帳から取り込み",
                    prefixIcon: Icon(Icons.business),
                    border: OutlineInputBorder(),
                  ),
                ),
              ),
              const SizedBox(width: 8),
              IconButton(
                icon: const Icon(Icons.person_add_alt_1, color: Colors.indigo, size: 40),
                onPressed: _openCustomerPicker,
                tooltip: "顧客を選択・登録",
              ),
            ]),
            const SizedBox(height: 16),
            TextField(
              controller: _amountController,
              keyboardType: TextInputType.number,
              decoration: const InputDecoration(
                labelText: "基本金額 (税抜)",
                hintText: "明細の1行目として登録されます",
                prefixIcon: Icon(Icons.currency_yen),
                border: OutlineInputBorder(),
              ),
            ),
            const SizedBox(height: 24),
            ElevatedButton.icon(
              onPressed: _handleInitialGenerate,
              icon: const Icon(Icons.description),
              label: Text("${_selectedType.label}を作成して詳細編集へ"),
              style: ElevatedButton.styleFrom(
                minimumSize: const Size(double.infinity, 60),
                backgroundColor: Colors.indigo,
                foregroundColor: Colors.white,
                elevation: 4,
                shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
              ),
            ),
            const SizedBox(height: 24),
            Container(
              width: double.infinity,
              padding: const EdgeInsets.all(12),
              decoration: BoxDecoration(
                color: Colors.grey[100],
                borderRadius: BorderRadius.circular(8),
                border: Border.all(color: Colors.grey.shade300),
              ),
              child: Text(
                _status,
                style: const TextStyle(fontSize: 12, color: Colors.black54),
                textAlign: TextAlign.center,
              ),
            ),
          ],
        ),
      ),
    );
  }
}