import 'dart:async';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:provider/provider.dart';
import 'package:xterm/xterm.dart';
import '../providers/auth_provider.dart';
import '../services/terminal_service.dart';

class TerminalScreen extends StatefulWidget {
  final String sessionName;

  const TerminalScreen({super.key, required this.sessionName});

  @override
  State<TerminalScreen> createState() => _TerminalScreenState();
}

class _TerminalScreenState extends State<TerminalScreen> {
  late Terminal _terminal;
  late TerminalService _terminalService;
  StreamSubscription? _outputSubscription;
  StreamSubscription? _stateSubscription;
  final _terminalController = TerminalController();

  @override
  void initState() {
    super.initState();
    _terminal = Terminal(
      maxLines: 10000,
    );
    _terminalService = TerminalService();
    _connect();
  }

  void _connect() {
    final auth = context.read<AuthProvider>();
    _terminalService.setToken(auth.token);

    _outputSubscription = _terminalService.output.listen((data) {
      _terminal.write(data);
    });

    _stateSubscription = _terminalService.connectionState.listen((state) {
      setState(() {});
      if (state == TerminalConnectionState.connected) {
        _terminal.write('Connected to ${widget.sessionName}\r\n');
      } else if (state == TerminalConnectionState.error) {
        _terminal.write('\r\n[Connection Error]\r\n');
      }
    });

    _terminal.onOutput = (data) {
      _terminalService.sendInput(data);
    };

    _terminal.onResize = (width, height, pixelWidth, pixelHeight) {
      _terminalService.resize(height, width);
    };

    _terminalService.connect(widget.sessionName);
  }

  @override
  void dispose() {
    _outputSubscription?.cancel();
    _stateSubscription?.cancel();
    _terminalService.dispose();
    _terminalController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.sessionName),
        actions: [
          // Connection status indicator
          Padding(
            padding: const EdgeInsets.only(right: 8),
            child: Icon(
              Icons.circle,
              size: 12,
              color: switch (_terminalService.currentState) {
                TerminalConnectionState.connected => Colors.green,
                TerminalConnectionState.connecting => Colors.orange,
                _ => Colors.red,
              },
            ),
          ),
          // Copy button
          IconButton(
            icon: const Icon(Icons.copy),
            onPressed: () {
              final selection = _terminalController.selection;
              if (selection != null) {
                final text = _terminal.buffer.getText(selection);
                Clipboard.setData(ClipboardData(text: text));
                ScaffoldMessenger.of(context).showSnackBar(
                  const SnackBar(content: Text('Copied to clipboard')),
                );
              }
            },
            tooltip: 'Copy Selection',
          ),
          // Paste button
          IconButton(
            icon: const Icon(Icons.paste),
            onPressed: () async {
              final data = await Clipboard.getData(Clipboard.kTextPlain);
              if (data?.text != null) {
                _terminalService.sendInput(data!.text!);
              }
            },
            tooltip: 'Paste',
          ),
          // Reconnect button
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: () {
              _terminalService.disconnect();
              _terminal.write('\r\n[Reconnecting...]\r\n');
              _connect();
            },
            tooltip: 'Reconnect',
          ),
        ],
      ),
      body: SafeArea(
        child: TerminalView(
          _terminal,
          controller: _terminalController,
          textStyle: const TerminalStyle(
            fontSize: 13,
            fontFamily: 'JetBrainsMono',
          ),
          theme: const TerminalTheme(
            cursor: Color(0xFFD97706),
            selection: Color(0x40D97706),
            foreground: Color(0xFFE5E5E5),
            background: Color(0xFF1A1A1A),
            black: Color(0xFF1A1A1A),
            red: Color(0xFFEF4444),
            green: Color(0xFF22C55E),
            yellow: Color(0xFFEAB308),
            blue: Color(0xFF3B82F6),
            magenta: Color(0xFFA855F7),
            cyan: Color(0xFF06B6D4),
            white: Color(0xFFE5E5E5),
            brightBlack: Color(0xFF6B7280),
            brightRed: Color(0xFFF87171),
            brightGreen: Color(0xFF4ADE80),
            brightYellow: Color(0xFFFDE047),
            brightBlue: Color(0xFF60A5FA),
            brightMagenta: Color(0xFFC084FC),
            brightCyan: Color(0xFF22D3EE),
            brightWhite: Color(0xFFFFFFFF),
            searchHitBackground: Color(0xFFD97706),
            searchHitBackgroundCurrent: Color(0xFFEF4444),
            searchHitForeground: Color(0xFF1A1A1A),
          ),
          autofocus: true,
          alwaysShowCursor: true,
        ),
      ),
      // Quick action buttons for mobile
      bottomNavigationBar: Container(
        height: 48,
        color: const Color(0xFF2D2D2D),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: [
            _buildQuickButton('Ctrl+C', () => _terminalService.sendInput('\x03')),
            _buildQuickButton('Ctrl+D', () => _terminalService.sendInput('\x04')),
            _buildQuickButton('Tab', () => _terminalService.sendInput('\t')),
            _buildQuickButton('Esc', () => _terminalService.sendInput('\x1b')),
            _buildQuickButton('Up', () => _terminalService.sendInput('\x1b[A')),
            _buildQuickButton('Down', () => _terminalService.sendInput('\x1b[B')),
          ],
        ),
      ),
    );
  }

  Widget _buildQuickButton(String label, VoidCallback onTap) {
    return InkWell(
      onTap: onTap,
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
        child: Text(
          label,
          style: TextStyle(
            color: Colors.grey.shade400,
            fontSize: 12,
            fontWeight: FontWeight.w500,
          ),
        ),
      ),
    );
  }
}