import 'package:flutter/material.dart';
import 'package:flutter/services.dart' show rootBundle;
import 'package:flutter_markdown/flutter_markdown.dart';

class ChangelogPage extends StatefulWidget {
  const ChangelogPage({super.key});

  @override
  State<ChangelogPage> createState() => _ChangelogPageState();
}

class _ChangelogPageState extends State<ChangelogPage> {
  String _markdownContent = '';
  bool _isLoading = true;
  String? _error;

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

  Future<void> _loadChangelog() async {
    try {
      final content = await rootBundle.loadString('assets/CHANGELOG.md');
      setState(() {
        _markdownContent = content;
        _isLoading = false;
      });
    } catch (e) {
      setState(() {
        _error = '无法加载更新日志: $e';
        _isLoading = false;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,
      appBar: AppBar(
        title: const Text(
          '更新日志',
          style: TextStyle(
            fontFamily: 'HarmonyOS_Sans_SC',
            color: Colors.black,
          ),
        ),
        backgroundColor: Colors.white,
        elevation: 0,
        foregroundColor: Colors.black,
        iconTheme: const IconThemeData(color: Colors.black),
      ),
      body: _isLoading
          ? const Center(child: CircularProgressIndicator())
          : _error != null
          ? Center(
              child: Text(
                _error!,
                style: const TextStyle(
                  fontFamily: 'HarmonyOS_Sans_SC',
                  color: Colors.grey,
                ),
              ),
            )
          : SingleChildScrollView(
              padding: const EdgeInsets.all(20),
              child: Markdown(
                data: _markdownContent,
                styleSheet: MarkdownStyleSheet(
                  h1: const TextStyle(
                    fontFamily: 'HarmonyOS_Sans_SC',
                    fontSize: 24,
                    fontWeight: FontWeight.w700,
                    color: Colors.black,
                  ),
                  h2: const TextStyle(
                    fontFamily: 'HarmonyOS_Sans_SC',
                    fontSize: 20,
                    fontWeight: FontWeight.w600,
                    color: Colors.black87,
                  ),
                  p: const TextStyle(
                    fontFamily: 'HarmonyOS_Sans_SC',
                    fontSize: 16,
                    color: Colors.black87,
                  ),
                  listBullet: const TextStyle(
                    fontFamily: 'HarmonyOS_Sans_SC',
                    fontSize: 16,
                    color: Colors.black87,
                  ),
                ),
              ),
            ),
    );
  }
}