import 'dart:ui';

import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:flutter/services.dart'; // 复制功能需要
import 'package:win_text_editor/app/providers/editor_provider.dart';
import 'package:file_picker/file_picker.dart';
import 'dart:io';
import 'package:flutter_highlight/flutter_highlight.dart';
import 'package:flutter_highlight/themes/github.dart';
import 'package:flutter_highlight/themes/monokai-sublime.dart';

class TextTab extends StatefulWidget {
  final String tabId;

  const TextTab({super.key, required this.tabId});

  @override
  State<TextTab> createState() => _TextTabState();
}

class _TextTabState extends State<TextTab> {
  late TextEditingController _controller;
  late EditorProvider _provider;
  late FocusNode _focusNode;
  late ScrollController _scrollController;
  String _language = 'plaintext';

  @override
  void initState() {
    super.initState();
    _provider = Provider.of<EditorProvider>(context, listen: false);
    _controller = TextEditingController(text: _getCurrentContent());
    _focusNode = FocusNode();
    _scrollController = ScrollController(); // 添加这行
    _detectLanguage();
  }

  String _getCurrentContent() {
    return _provider.tabs.firstWhere((t) => t.id == widget.tabId).content;
  }

  void _detectLanguage() {
    final tab = _provider.tabs.firstWhere((t) => t.id == widget.tabId);
    final fileName = tab.title.toLowerCase();
    final content = tab.content.trim();

    if (fileName.endsWith('.dart')) {
      _language = 'dart';
    } else if (fileName.endsWith('.java')) {
      _language = 'java';
    } else if (fileName.endsWith('.py')) {
      _language = 'python';
    } else if (fileName.endsWith('.js')) {
      _language = 'javascript';
    } else if (fileName.endsWith('.html')) {
      _language = 'html';
    } else if (fileName.endsWith('.css')) {
      _language = 'css';
    } else if (fileName.endsWith('.json')) {
      _language = 'json';
    } else if (fileName.endsWith('.yaml') || fileName.endsWith('.yml')) {
      _language = 'yaml';
    } else if (fileName.endsWith('.xml')) {
      _language = 'xml';
    }
    // 如果扩展名未识别，检查内容特征
    else if (_isLikelyXml(content)) {
      _language = 'xml';
    } else {
      _language = 'plaintext';
    }
  }

  bool _isLikelyXml(String content) {
    if (content.isEmpty) return false;

    // 简单检查：内容以'<'开头，以'>'结尾
    final trimmed = content.trim();
    if (!trimmed.startsWith('<') || !trimmed.endsWith('>')) {
      return false;
    }

    // 更复杂的检查：包含常见的XML标签模式
    final xmlTagRegex = RegExp(r'<[^/>]+>.*<\/[^>]+>|<[^/>]+\/>');
    return xmlTagRegex.hasMatch(content);
  }

  @override
  void didUpdateWidget(TextTab oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (oldWidget.tabId != widget.tabId) {
      _controller.text = _getCurrentContent();
      _detectLanguage();
    }
  }

  @override
  void dispose() {
    _controller.dispose();
    _focusNode.dispose();
    _scrollController.dispose(); // 添加这行
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final tab = _provider.tabs.firstWhere((t) => t.id == widget.tabId);
    final isDarkMode = Theme.of(context).brightness == Brightness.dark;

    return Column(
      children: [
        Container(
          height: 40,
          padding: const EdgeInsets.symmetric(horizontal: 16),
          decoration: BoxDecoration(
            color: Colors.grey[100],
            border: Border(bottom: BorderSide(color: Colors.grey[300]!)),
          ),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Text(
                '源文本${tab.content.isEmpty ? '' : ' (${tab.content.length}字符)'}',
                style: const TextStyle(fontWeight: FontWeight.bold),
              ),
              Row(
                children: [
                  IconButton(
                    icon: const Icon(Icons.folder_open, size: 20),
                    tooltip: '打开文件',
                    onPressed: () => _openFile(context),
                  ),
                  IconButton(
                    icon: const Icon(Icons.content_copy, size: 20),
                    tooltip: '复制内容',
                    onPressed:
                        tab.content.isEmpty ? null : () => _copyToClipboard(context, tab.content),
                  ),
                  IconButton(
                    icon: const Icon(Icons.save, size: 20),
                    tooltip: '保存到文件',
                    onPressed: tab.content.isEmpty ? null : () => _saveFile(context, tab.content),
                  ),
                  DropdownButton<String>(
                    value: _language,
                    icon: const Icon(Icons.code, size: 20),
                    underline: Container(),
                    onChanged: (String? newValue) {
                      setState(() {
                        _language = newValue!;
                      });
                    },
                    items:
                        <String>[
                          'xml',
                          'plaintext',
                          'dart',
                          'java',
                          'python',
                          'javascript',
                          'html',
                          'css',
                          'json',
                          'yaml',
                        ].map<DropdownMenuItem<String>>((String value) {
                          return DropdownMenuItem<String>(value: value, child: Text(value));
                        }).toList(),
                  ),
                ],
              ),
            ],
          ),
        ),
        Expanded(
          child: ScrollConfiguration(
            behavior: ScrollConfiguration.of(context).copyWith(
              scrollbars: true,
              dragDevices: {PointerDeviceKind.touch, PointerDeviceKind.mouse},
            ),
            child: SingleChildScrollView(
              controller: _scrollController, // 添加滚动控制器
              child: Stack(
                children: [
                  // 高亮显示的背景文本
                  HighlightView(
                    tab.content,
                    language: _language,
                    theme: isDarkMode ? monokaiSublimeTheme : githubTheme,
                    padding: const EdgeInsets.all(16),
                    textStyle: const TextStyle(fontFamily: 'monospace', fontSize: 14),
                  ),
                  // 实际可编辑的TextField
                  TextField(
                    controller: _controller,
                    focusNode: _focusNode,
                    maxLines: null,
                    scrollController: _scrollController, // 使用同一个滚动控制器
                    onChanged: (text) => _provider.updateContent(widget.tabId, text),
                    decoration: const InputDecoration(
                      border: InputBorder.none,
                      contentPadding: EdgeInsets.all(16),
                    ),
                    style: const TextStyle(
                      fontFamily: 'monospace',
                      fontSize: 14,
                      color: Colors.transparent,
                    ),
                    cursorColor: Colors.black,
                  ),
                ],
              ),
            ),
          ),
        ),
      ],
    );
  }

  // _openFile方法现在需要更新控制器
  Future<void> _openFile(BuildContext context) async {
    try {
      final result = await FilePicker.platform.pickFiles(type: FileType.any, allowMultiple: false);

      if (result != null && result.files.single.path != null) {
        final file = File(result.files.single.path!);
        final content = await file.readAsString();

        _provider.updateContent(widget.tabId, content);
        setState(() {
          _controller.text = content;
          _detectLanguage();
        });

        // 强制刷新文本控制器
        if (context.mounted) {
          ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('已加载: ${file.path}')));
        }
      }
    } on FormatException {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('这不是可读的文本文件')));
    } on FileSystemException catch (e) {
      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('文件访问错误: ${e.message}')));
    } catch (e) {
      if (context.mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('读取失败: ${e.toString()}')));
      }
    }
  }

  // 复制到剪贴板
  Future<void> _copyToClipboard(BuildContext context, String content) async {
    await Clipboard.setData(ClipboardData(text: content));
    if (context.mounted) {
      ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('已复制到剪贴板')));
    }
  }

  // 保存文件模拟功能
  // 保存文件功能
  Future<void> _saveFile(BuildContext context, String content) async {
    try {
      // 让用户选择保存位置
      String? outputPath = await FilePicker.platform.saveFile(
        dialogTitle: '保存文件',
        fileName: 'untitled.txt',
        allowedExtensions: ['txt'],
        type: FileType.any,
      );

      if (outputPath == null) return;

      final file = File(outputPath);

      // 检查文件是否存在
      if (await file.exists()) {
        // 如果存在，显示确认对话框
        final shouldOverwrite = await showDialog<bool>(
          context: context,
          builder:
              (context) => AlertDialog(
                title: const Text('文件已存在'),
                content: const Text('要覆盖现有文件吗？'),
                actions: [
                  TextButton(
                    onPressed: () => Navigator.pop(context, false),
                    child: const Text('取消'),
                  ),
                  TextButton(
                    onPressed: () => Navigator.pop(context, true),
                    child: const Text('覆盖'),
                  ),
                ],
              ),
        );

        if (shouldOverwrite != true) return;
      }

      // 写入文件
      await file.writeAsString(content);

      if (context.mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('已保存到: ${file.path}')));
      }
    } on FileSystemException catch (e) {
      if (context.mounted) {
        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text('保存失败: ${e.message}')));
      }
    } catch (e) {
      if (context.mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('保存失败: ${e.toString()}')));
      }
    }
  }
}