import 'dart:async';
import 'dart:typed_data';

import 'package:flutter/material.dart';

import '../app/app_controller.dart';
import '../core/sqlite_reader.dart';
import '../core/vfs.dart';
import '../l10n/tr.dart';
import 'theme.dart';
import 'jj_title_bar.dart';

/// SQLite 로 볼 확장자
const sqliteExtensions = {'db', 'sqlite', 'sqlite3', 'db3'};

/// X-plore 비교 5-1 ④ (관리자 지시 10/21): SQLite 보기 (읽기 전용) - 원격 파일은 임시로 받아서 연다
Future<void> openSqliteViewer(BuildContext context, AppController c, String path) =>
    Navigator.of(context).push(MaterialPageRoute<void>(builder: (_) => SqliteViewerPage(c: c, path: path)));

class SqliteViewerPage extends StatefulWidget {
  final AppController c;
  final String path;
  const SqliteViewerPage({super.key, required this.c, required this.path});

  @override
  State<SqliteViewerPage> createState() => _SqliteViewerPageState();
}

class _SqliteViewerPageState extends State<SqliteViewerPage> {
  static const _pageRows = 200;
  SqliteFile? _db;
  List<SqliteTable> _tables = const [];
  SqliteTable? _table;
  List<SqliteRow> _rows = const [];
  int? _count;
  bool _more = false, _busy = true;
  String? _error;

  @override
  void initState() {
    super.initState();
    unawaited(_open());
  }

  @override
  void dispose() {
    unawaited(_db?.close());
    super.dispose();
  }

  Future<void> _open() async {
    try {
      final local = isDav(widget.path) ? await vLocalCopy(widget.path, await widget.c.services.storage.tempDirectory()) : widget.path;
      final db = await SqliteFile.open(local);
      if (!mounted) {
        await db.close();
        return;
      }
      _db = db;
      _tables = await db.tables();
      if (_tables.isNotEmpty) {
        await _pick(_tables.first);
      } else if (mounted) {
        setState(() => _busy = false);
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _busy = false;
          _error = e is SqliteFormatException ? tr('SQLite 파일이 아니거나 깨졌습니다') : trf('열 수 없습니다: {0}', [e]);
        });
      }
    }
  }

  Future<void> _pick(SqliteTable t) async {
    setState(() {
      _table = t;
      _rows = const [];
      _count = null;
      _busy = true;
      _error = null;
    });
    final db = _db!;
    try {
      if (t.withoutRowid) {
        setState(() {
          _busy = false;
          _error = tr('WITHOUT ROWID 테이블은 아직 볼 수 없습니다');
        });
        return;
      }
      final rows = await db.rows(t, limit: _pageRows);
      final count = await db.count(t);
      if (!mounted || _table != t) return;
      setState(() {
        _rows = rows;
        _count = count;
        _more = rows.length < count;
        _busy = false;
      });
    } catch (e) {
      if (mounted) {
        setState(() {
          _busy = false;
          _error = tr('SQLite 파일이 아니거나 깨졌습니다');
        });
      }
    }
  }

  Future<void> _loadMore() async {
    final t = _table!;
    setState(() => _busy = true);
    final more = await _db!.rows(t, offset: _rows.length, limit: _pageRows);
    if (!mounted || _table != t) return;
    setState(() {
      _rows = [..._rows, ...more];
      _more = _rows.length < (_count ?? 0);
      _busy = false;
    });
  }

  String _cell(Object? v) => switch (v) {
        null => 'NULL',
        Uint8List b => trf('(BLOB {0}바이트)', [b.length]),
        String s => s.length > 120 ? '${s.substring(0, 120).replaceAll('\n', ' ')} …' : s.replaceAll('\n', ' '),
        _ => '$v',
      };

  void _showCell(String column, Object? v) => showDialog<void>(
        context: context,
        builder: (ctx) => AlertDialog(
          scrollable: true,
          title: Text(column),
          content: SelectableText(
            v is Uint8List ? v.take(256).map((x) => x.toRadixString(16).padLeft(2, '0')).join(' ') + (v.length > 256 ? ' …' : '') : '${v ?? 'NULL'}',
            style: const TextStyle(fontSize: 13),
          ),
          actions: [TextButton(onPressed: () => Navigator.of(ctx).pop(), child: Text(tr('닫기')))],
        ),
      );

  @override
  Widget build(BuildContext context) {
    final t = _table;
    return Scaffold(
      appBar: jjTitleBar(
        context,
        title: vBasename(widget.path),
      ),
      body: Column(crossAxisAlignment: CrossAxisAlignment.stretch, children: [
        Padding(
          padding: const EdgeInsets.fromLTRB(12, 8, 12, 0),
          child: Text(tr('읽기 전용 - 이 앱은 파일을 바꾸지 않습니다. 쓰는 중인 바뀐 것 (-wal) 은 보이지 않을 수 있습니다'),
              style: TextStyle(fontSize: 12, color: JjColors.textDim)),
        ),
        if (_tables.isNotEmpty)
          Padding(
            padding: const EdgeInsets.symmetric(horizontal: 12),
            child: Row(children: [
              Expanded(
                child: DropdownButton<SqliteTable>(
                  isExpanded: true,
                  value: t,
                  items: [for (final x in _tables) DropdownMenuItem(value: x, child: Text(x.name, overflow: TextOverflow.ellipsis))],
                  onChanged: _busy ? null : (x) => _pick(x!),
                ),
              ),
              const SizedBox(width: 8),
              if (_count != null) Text(trf('{0}행', [_count!]), style: TextStyle(color: JjColors.textDim)),
            ]),
          ),
        if (_error != null)
          Padding(padding: const EdgeInsets.all(16), child: Text(_error!, style: TextStyle(color: JjColors.danger))),
        if (_busy && _rows.isEmpty) const Padding(padding: EdgeInsets.all(24), child: Center(child: CircularProgressIndicator())),
        if (!_busy && _error == null && _tables.isEmpty) Padding(padding: const EdgeInsets.all(16), child: Text(tr('테이블이 없습니다'))),
        if (t != null && _rows.isNotEmpty)
          Expanded(
            child: Scrollbar(
              child: SingleChildScrollView(
                child: SingleChildScrollView(
                  scrollDirection: Axis.horizontal,
                  child: DataTable(
                    headingRowHeight: 36,
                    dataRowMinHeight: 32,
                    dataRowMaxHeight: 40,
                    columns: [for (final col in t.displayColumns) DataColumn(label: Text(col, style: const TextStyle(fontWeight: FontWeight.w600)))],
                    rows: [
                      for (final r in _rows)
                        DataRow(cells: [
                          for (var i = 0; i < t.columns.length; i++)
                            DataCell(
                              ConstrainedBox(
                                constraints: const BoxConstraints(maxWidth: 280),
                                child: Text(_cell(i < r.values.length ? r.values[i] : null),
                                    maxLines: 1,
                                    overflow: TextOverflow.ellipsis,
                                    style: TextStyle(color: (i < r.values.length ? r.values[i] : null) == null ? JjColors.textDim : null)),
                              ),
                              onTap: () => _showCell(t.displayColumns[i], i < r.values.length ? r.values[i] : null),
                            ),
                        ]),
                    ],
                  ),
                ),
              ),
            ),
          ),
        if (_more)
          Padding(
            padding: const EdgeInsets.all(8),
            child: OutlinedButton(
              onPressed: _busy ? null : _loadMore,
              child: Text(trf('더 보기 ({0} / {1})', [_rows.length, _count ?? 0])),
            ),
          ),
      ]),
    );
  }
}