import 'dart:async';
import 'dart:convert';
import 'dart:io';

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:wakelock_plus/wakelock_plus.dart';

import 'package:external_cam/frame_server.dart';

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

  @override
  State<ViewerScreen> createState() => _ViewerScreenState();
}

class _ViewerScreenState extends State<ViewerScreen> {
  final _ipController = TextEditingController();
  WebSocket? _socket;
  Uint8List? _currentFrame;
  bool _isConnected = false;
  bool _isSearching = true;
  bool _isConnecting = false;
  int _fps = 0;
  int _frameCount = 0;
  int _rotation = 0;
  bool _mirrored = false;
  Timer? _fpsTimer;

  int _cameraCount = 0;
  bool _flashOn = false;
  String _lensDirection = '';
  String _cameraName = '';
  double _zoom = 1.0;
  double _minZoom = 1.0;
  double _maxZoom = 1.0;
  int _quality = 50;

  @override
  void initState() {
    super.initState();
    SystemChrome.setPreferredOrientations([
      DeviceOrientation.landscapeLeft,
      DeviceOrientation.landscapeRight,
    ]);
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.immersiveSticky);
    _autoDiscover();
  }

  Future<void> _autoDiscover() async {
    setState(() => _isSearching = true);
    final ip = await discoverServer();
    if (!mounted) return;

    if (ip != null) {
      _ipController.text = ip;
      _connectTo(ip);
    } else {
      setState(() => _isSearching = false);
    }
  }

  Future<void> _connectTo(String ip) async {
    if (_isConnecting) return;
    setState(() {
      _isConnecting = true;
      _isSearching = false;
    });

    try {
      _socket = await WebSocket.connect(
        'ws://$ip:$serverPort/stream',
      ).timeout(const Duration(seconds: 5));

      _fpsTimer = Timer.periodic(const Duration(seconds: 1), (_) {
        if (!mounted) return;
        setState(() {
          _fps = _frameCount;
          _frameCount = 0;
        });
      });

      _socket!.listen(
        _onData,
        onDone: _onDisconnected,
        onError: (_) => _onDisconnected(),
      );

      setState(() {
        _isConnected = true;
        _isConnecting = false;
      });
      WakelockPlus.enable();
    } catch (error) {
      setState(() => _isConnecting = false);
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Connection failed: $error')));
      }
    }
  }

  void _connect() {
    final ip = _ipController.text.trim();
    if (ip.isNotEmpty) _connectTo(ip);
  }

  void _onData(dynamic data) {
    if (data is List<int>) {
      setState(() {
        _currentFrame = Uint8List.fromList(data);
        _frameCount++;
      });
    } else if (data is String) {
      _handleState(data);
    }
  }

  void _handleState(String json) {
    try {
      final state = jsonDecode(json) as Map<String, dynamic>;
      setState(() {
        _cameraCount = state['cameras'] as int? ?? 0;
        _flashOn = state['flash'] as bool? ?? false;
        _lensDirection = state['lens'] as String? ?? '';
        _cameraName = state['name'] as String? ?? '';
        _zoom = (state['zoom'] as num?)?.toDouble() ?? 1.0;
        _minZoom = (state['minZoom'] as num?)?.toDouble() ?? 1.0;
        _maxZoom = (state['maxZoom'] as num?)?.toDouble() ?? 1.0;
        _quality = state['quality'] as int? ?? 50;
      });
    } catch (_) {}
  }

  void _sendCommand(String command) => _socket?.add(command);

  void _onDisconnected() {
    _fpsTimer?.cancel();
    _fpsTimer = null;
    if (!mounted) return;
    setState(() {
      _isConnected = false;
      _currentFrame = null;
    });
    WakelockPlus.disable();
  }

  void _disconnect() {
    _socket?.close();
    _onDisconnected();
  }

  void _cycleRotation() {
    setState(() => _rotation = (_rotation + 1) % 4);
  }

  @override
  void dispose() {
    _fpsTimer?.cancel();
    _socket?.close();
    _ipController.dispose();
    WakelockPlus.disable();
    SystemChrome.setPreferredOrientations(DeviceOrientation.values);
    SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    if (_isConnected) return _buildViewer();
    return _buildConnectScreen();
  }

  Widget _buildConnectScreen() {
    return Scaffold(
      appBar: AppBar(title: const Text('Viewer')),
      body: Center(
        child: Padding(
          padding: const EdgeInsets.all(32),
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              if (_isSearching) ...[
                const CircularProgressIndicator(),
                const SizedBox(height: 16),
                const Text('Searching for camera...'),
              ] else ...[
                TextField(
                  controller: _ipController,
                  decoration: const InputDecoration(
                    labelText: 'Camera IP address',
                    border: OutlineInputBorder(),
                  ),
                  keyboardType: TextInputType.number,
                  onSubmitted: (_) => _connect(),
                ),
                const SizedBox(height: 16),
                Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    FilledButton.icon(
                      onPressed: _isConnecting ? null : _connect,
                      icon: _isConnecting
                          ? const SizedBox(
                              width: 16,
                              height: 16,
                              child: CircularProgressIndicator(strokeWidth: 2),
                            )
                          : const Icon(Icons.play_arrow),
                      label: Text(_isConnecting ? 'Connecting...' : 'Connect'),
                    ),
                    const SizedBox(width: 16),
                    OutlinedButton.icon(
                      onPressed: _isConnecting ? null : _autoDiscover,
                      icon: const Icon(Icons.search),
                      label: const Text('Search'),
                    ),
                  ],
                ),
              ],
            ],
          ),
        ),
      ),
    );
  }

  Widget _buildViewer() {
    return Scaffold(
      backgroundColor: Colors.black,
      body: Stack(
        fit: StackFit.expand,
        children: [
          if (_currentFrame != null)
            Center(
              child: Transform.flip(
                flipX: _mirrored,
                child: RotatedBox(
                  quarterTurns: _rotation,
                  child: Image.memory(
                    _currentFrame!,
                    gaplessPlayback: true,
                    fit: BoxFit.contain,
                  ),
                ),
              ),
            ),
          _buildTopBar(),
          _buildBottomControls(),
        ],
      ),
    );
  }

  Widget _buildTopBar() {
    return Positioned(
      top: 16,
      right: 16,
      child: SafeArea(
        child: Container(
          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
          decoration: BoxDecoration(
            color: Colors.black54,
            borderRadius: BorderRadius.circular(8),
          ),
          child: Row(
            mainAxisSize: MainAxisSize.min,
            children: [
              const Icon(Icons.circle, color: Colors.green, size: 12),
              const SizedBox(width: 8),
              Text('$_fps fps'),
              if (_cameraName.isNotEmpty) ...[
                const SizedBox(width: 8),
                Text(
                  '$_lensDirection $_cameraName',
                  style: const TextStyle(fontSize: 12),
                ),
              ],
            ],
          ),
        ),
      ),
    );
  }

  List<double> get _availableZoomPresets {
    const presets = [0.5, 1.0, 2.0, 3.0, 5.0, 10.0];
    return presets.where((z) => z >= _minZoom && z <= _maxZoom).toList();
  }

  Widget _buildBottomControls() {
    return Positioned(
      bottom: 0,
      left: 0,
      right: 0,
      child: SafeArea(
        child: Container(
          padding: const EdgeInsets.symmetric(vertical: 8, horizontal: 8),
          decoration: const BoxDecoration(
            gradient: LinearGradient(
              begin: Alignment.bottomCenter,
              end: Alignment.topCenter,
              colors: [Colors.black54, Colors.transparent],
            ),
          ),
          child: Row(
            children: [
              IconButton(
                onPressed: _disconnect,
                icon: const Icon(Icons.close, size: 20),
                visualDensity: VisualDensity.compact,
              ),
              if (_cameraCount > 1)
                IconButton(
                  onPressed: () => _sendCommand('switch_camera'),
                  icon: const Icon(Icons.flip_camera_android, size: 20),
                  visualDensity: VisualDensity.compact,
                ),
              IconButton(
                onPressed: () => _sendCommand('toggle_flash'),
                icon: Icon(
                  _flashOn ? Icons.flash_on : Icons.flash_off,
                  size: 20,
                ),
                visualDensity: VisualDensity.compact,
              ),
              IconButton(
                onPressed: _cycleRotation,
                icon: const Icon(Icons.rotate_right, size: 20),
                visualDensity: VisualDensity.compact,
              ),
              IconButton(
                onPressed: () => setState(() => _mirrored = !_mirrored),
                icon: const Icon(Icons.flip, size: 20),
                visualDensity: VisualDensity.compact,
              ),
              const Spacer(),
              if (_availableZoomPresets.length > 1)
                ..._buildChipGroup(
                  _availableZoomPresets.map((level) {
                    final active = (_zoom - level).abs() < 0.1;
                    final label = level == level.roundToDouble()
                        ? '${level.toInt()}x'
                        : '${level}x';
                    return _chip(label, active, () => _sendCommand('zoom:$level'));
                  }),
                ),
              const SizedBox(width: 8),
              ..._buildChipGroup(
                [30, 50, 70, 90].map(
                  (q) => _chip('$q%', _quality == q, () => _sendCommand('quality:$q')),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  List<Widget> _buildChipGroup(Iterable<Widget> chips) => chips.toList();

  Widget _chip(String label, bool active, VoidCallback onTap) {
    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 2),
      child: GestureDetector(
        onTap: onTap,
        child: Container(
          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
          decoration: BoxDecoration(
            color: active ? Colors.white24 : Colors.transparent,
            borderRadius: BorderRadius.circular(12),
            border: Border.all(
              color: active ? Colors.white70 : Colors.white30,
            ),
          ),
          child: Text(
            label,
            style: TextStyle(
              fontSize: 11,
              color: active ? Colors.white : Colors.white70,
            ),
          ),
        ),
      ),
    );
  }
}