import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:accessible_terminal/state/terminal_provider.dart';
import 'package:dartssh2/dartssh2.dart';
import 'file_editor_view.dart';

class FileBrowserView extends ConsumerStatefulWidget {
  final String initialPath;
  const FileBrowserView({super.key, this.initialPath = '.'});

  @override
  ConsumerState<FileBrowserView> createState() => _FileBrowserViewState();
}

class _FileBrowserViewState extends ConsumerState<FileBrowserView> {
  late String _currentPath;
  List<SftpName>? _files;
  bool _isLoading = true;
  String? _error;

  @override
  void initState() {
    super.initState();
    _currentPath = widget.initialPath;
    _loadDirectory();
  }

  Future<void> _loadDirectory() async {
    setState(() {
      _isLoading = true;
      _error = null;
    });

    try {
      final sshService = ref.read(sshServiceProvider);
      final files = await sshService.listDirectory(_currentPath);
      
      // Sort: Directories first, then alphabetically
      files.sort((a, b) {
        if (a.attr.isDirectory && !b.attr.isDirectory) return -1;
        if (!a.attr.isDirectory && b.attr.isDirectory) return 1;
        return a.filename.toLowerCase().compareTo(b.filename.toLowerCase());
      });

      if (mounted) {
        setState(() {
          _files = files.where((f) => f.filename != '.' && f.filename != '..').toList();
          _isLoading = false;
        });
      }
    } catch (e) {
      if (mounted) {
        setState(() {
          _error = e.toString();
          _isLoading = false;
        });
      }
    }
  }

  void _navigate(String filename) {
    setState(() {
      if (_currentPath == '/') {
        _currentPath = '/$filename';
      } else {
        _currentPath = '$_currentPath/$filename'.replaceAll('//', '/');
      }
    });
    _loadDirectory();
  }

  void _goUp() {
    if (_currentPath == '/' || _currentPath == '.') return;
    final parts = _currentPath.split('/');
    parts.removeLast();
    setState(() {
      _currentPath = parts.isEmpty ? '/' : parts.join('/');
      if (_currentPath.isEmpty) _currentPath = '/';
    });
    _loadDirectory();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(_currentPath),
        actions: [
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: _loadDirectory,
            tooltip: 'Refresh',
          ),
        ],
      ),
      body: _buildBody(),
    );
  }

  Widget _buildBody() {
    if (_isLoading) {
      return const Center(child: CircularProgressIndicator());
    }

    if (_error != null) {
      return Center(
        child: Padding(
          padding: const EdgeInsets.all(16.0),
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              const Icon(Icons.error, color: Colors.red, size: 48),
              const SizedBox(height: 16),
              Text('Error: $_error', textAlign: TextAlign.center),
              const SizedBox(height: 16),
              ElevatedButton(onPressed: _loadDirectory, child: const Text('Retry')),
            ],
          ),
        ),
      );
    }

    return Column(
      children: [
        if (_currentPath != '/' && _currentPath != '.')
          ListTile(
            leading: const Icon(Icons.arrow_upward),
            title: const Text('.. (Go Up)'),
            onTap: _goUp,
          ),
        Expanded(
          child: ListView.builder(
            itemCount: _files?.length ?? 0,
            itemBuilder: (context, index) {
              final file = _files![index];
              final isDir = file.attr.isDirectory;

              return ListTile(
                leading: Icon(isDir ? Icons.folder : Icons.insert_drive_file),
                title: Text(file.filename),
                subtitle: isDir ? null : Text(_formatSize(file.attr.size ?? 0)),
                onTap: () {
                  if (isDir) {
                    _navigate(file.filename);
                  } else {
                    _openFile(file.filename);
                  }
                },
              );
            },
          ),
        ),
      ],
    );
  }

  String _formatSize(int bytes) {
    if (bytes < 1024) return '$bytes B';
    if (bytes < 1024 * 1024) return '${(bytes / 1024).toStringAsFixed(1)} KB';
    return '${(bytes / (1024 * 1024)).toStringAsFixed(1)} MB';
  }

  void _openFile(String filename) {
    final fullPath = _currentPath == '/' ? '/$filename' : '$_currentPath/$filename';
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => FileEditorView(path: fullPath),
      ),
    ).then((_) => _loadDirectory()); // Refresh on return in case of changes
  }
}