import 'dart:async';
import 'dart:developer';
import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter_webrtc/flutter_webrtc.dart';
import 'package:provider/provider.dart';
import 'package:test_sa/extensions/int_extensions.dart';
import 'package:test_sa/extensions/text_extensions.dart';
import 'package:test_sa/extensions/widget_extensions.dart';
import 'package:test_sa/modules/cx_module/chat/services/call_manager.dart';
import 'package:test_sa/modules/cx_module/chat/model/call_session.dart';
import 'package:test_sa/modules/cx_module/chat/call/utils/permission_helper.dart';
import 'package:test_sa/new_views/app_style/app_color.dart';

class VideoCallPage extends StatefulWidget {
  const VideoCallPage({Key? key}) : super(key: key);

  @override
  State<VideoCallPage> createState() => _VideoCallPageState();
}

class _VideoCallPageState extends State<VideoCallPage> {
  late CallManager _callManager;
  Timer? _streamCheckTimer;
  bool _isLocalVideoFullscreen = false;

  @override
  void initState() {
    super.initState();
    // HYBRID: Get CallManager from Provider (UI layer)
    _callManager = Provider.of<CallManager>(context, listen: false);

    // Listen for call end
    _callManager.addListener(_checkCallStatus);

    // Start periodic check to ensure remote stream gets assigned
    _startStreamCheckTimer();
    
    // CRITICAL: Check permissions after first frame
    // Permissions must be requested in UI layer, not service layer
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _checkPermissions();
    });
  }

  /// Request video call permissions using production-ready helper
  Future<void> _checkPermissions() async {
    if (!mounted) return;
    
    // Request all video call permissions (microphone + camera)
    final granted = await CallPermissionHelper.requestVideoCallPermissions(context);
    
    if (!granted && mounted) {
      // Permission denied - end the call gracefully
      await CallPermissionHelper.handlePermissionDeniedDuringCall(
        context,
        'Camera or Microphone',
        onEndCall: () => _callManager.declineCall('permission_denied'),
        delaySeconds: 2,
      );
    }
  }

  void _startStreamCheckTimer() {
    _streamCheckTimer = Timer.periodic(const Duration(milliseconds: 500), (timer) {
      final webrtc = _callManager.webrtcService;

      if (webrtc == null || !mounted) {
        timer.cancel();
        return;
      }

      // If we have remote stream but renderer doesn't have it, assign it
      if (webrtc.remoteStream != null &&
          webrtc.remoteRenderer != null &&
          webrtc.remoteRenderer!.srcObject == null) {
        try {
          webrtc.remoteRenderer!.srcObject = webrtc.remoteStream;
          if (mounted) setState(() {});
        } catch (e) {
          if (kDebugMode) {
            log('⚠️ Stream assignment failed: $e', name: 'VideoCallPage');
          }
        }
      }

      // If call is connected and remote stream is assigned, slow down checks
      if (_callManager.callStatus == CallStatus.connected &&
          webrtc.remoteRenderer?.srcObject != null) {
        timer.cancel();
      }
    });
  }

  void _checkCallStatus() {
    if (_callManager.callStatus == CallStatus.idle && mounted) {
      Navigator.of(context).pop();
    }
  }

  @override
  void dispose() {
    _streamCheckTimer?.cancel();
    _callManager.removeListener(_checkCallStatus);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: AppColor.backgroundTabBarDark,
      body: SafeArea(
        top: false,
        child: ListenableBuilder(
          listenable: _callManager,
          builder: (context, _) {
            final session = _callManager.currentCall;
            if (session == null) {
              return const Center(
                child: Text('No active call', style: TextStyle(color: Colors.white)),
              );
            }

            return Stack(
              children: [
                // Remote video (fullscreen by default)
                if (!_isLocalVideoFullscreen) _buildRemoteVideo(context),

                // Local video (fullscreen when tapped)
                if (_isLocalVideoFullscreen) _buildFullscreenLocalVideo(context),

                // Small preview (top-right corner)
                if (_isLocalVideoFullscreen)
                  _buildSmallRemoteVideo(context)
                else
                  _buildLocalVideoPreview(context),

                _buildTopBar(context, session),
                _buildBottomControls(context, session),
              ],
            );
          },
        ),
      ),
    );
  }

  Widget _buildRemoteVideo(BuildContext context) {
    final webrtc = _callManager.webrtcService;
    final isPeerCameraOn = _callManager.isPeerCameraOn;

    return Positioned.fill(
      child: GestureDetector(
        onTap: () => setState(() => _isLocalVideoFullscreen = true),
        child: Container(
          color: Colors.black,
          child: !isPeerCameraOn || webrtc?.remoteRenderer == null
              ? _buildAvatarPlaceholder(_callManager.currentCall?.peerName ?? 'User', large: true)
              : RTCVideoView(
                  webrtc!.remoteRenderer!,
                  objectFit: RTCVideoViewObjectFit.RTCVideoViewObjectFitCover,
                ),
        ),
      ),
    );
  }

  Widget _buildFullscreenLocalVideo(BuildContext context) {
    final webrtc = _callManager.webrtcService;
    final isCameraOn = _callManager.isCameraOn;

    return Positioned.fill(
      child: GestureDetector(
        onTap: () => setState(() => _isLocalVideoFullscreen = false),
        child: Container(
          color: Colors.grey[800],
          child: !isCameraOn || webrtc?.localRenderer == null
              ? const Center(child: Icon(Icons.videocam_off, color: Colors.white, size: 64))
              : RTCVideoView(
                  webrtc!.localRenderer!,
                  objectFit: RTCVideoViewObjectFit.RTCVideoViewObjectFitCover,
                  mirror: true,
                ),
        ),
      ),
    );
  }

  Widget _buildLocalVideoPreview(BuildContext context) {
    final webrtc = _callManager.webrtcService;
    final isCameraOn = _callManager.isCameraOn;

    return Positioned(
      top: 100,
      right: 16,
      child: GestureDetector(
        onTap: () => setState(() => _isLocalVideoFullscreen = true),
        child: Container(
          width: 120,
          height: 160,
          decoration: BoxDecoration(
            color: Colors.grey[800],
            borderRadius: BorderRadius.circular(12),
            border: Border.all(color: Colors.white24, width: 2),
          ),
          child: ClipRRect(
            borderRadius: BorderRadius.circular(10),
            child: !isCameraOn || webrtc?.localRenderer == null
                ? const Center(child: Icon(Icons.videocam_off, color: Colors.white, size: 32))
                : RTCVideoView(
                    webrtc!.localRenderer!,
                    objectFit: RTCVideoViewObjectFit.RTCVideoViewObjectFitCover,
                    mirror: true,
                  ),
          ),
        ),
      ),
    );
  }

  Widget _buildSmallRemoteVideo(BuildContext context) {
    final webrtc = _callManager.webrtcService;
    final isPeerCameraOn = _callManager.isPeerCameraOn;

    return Positioned(
      top: 100,
      right: 16,
      child: GestureDetector(
        onTap: () => setState(() => _isLocalVideoFullscreen = false),
        child: Container(
          width: 120,
          height: 160,
          decoration: BoxDecoration(
            color: Colors.black,
            borderRadius: BorderRadius.circular(12),
            border: Border.all(color: Colors.white24, width: 2),
          ),
          child: ClipRRect(
            borderRadius: BorderRadius.circular(10),
            child: !isPeerCameraOn || webrtc?.remoteRenderer == null
                ? _buildAvatarPlaceholder(_callManager.currentCall?.peerName ?? 'User', large: false)
                : RTCVideoView(
                    webrtc!.remoteRenderer!,
                    objectFit: RTCVideoViewObjectFit.RTCVideoViewObjectFitCover,
                  ),
          ),
        ),
      ),
    );
  }

  Widget _buildAvatarPlaceholder(String name, {required bool large}) {
    return Container(
      color: AppColor.backgroundTabBarDark,
      child: Center(
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Icon(
              Icons.person,
              size: large ? 80 : 40,
              color: Colors.white54,
            ),
            if (large) ...[
              12.height,
              Text(
                name,
                style: AppTextStyles.heading5.copyWith(color: Colors.white),
              ),
              4.height,
              Text(
                'Camera is off',
                style: AppTextStyles.bodyText2.copyWith(color: Colors.white54),
              ),
            ],
          ],
        ),
      ),
    );
  }

  Widget _buildTopBar(BuildContext context, CallSession session) {
    final status = _callManager.callStatus;
    final duration = _callManager.callDuration;

    String statusText;
    if (status == CallStatus.connected) {
      final minutes = duration.inMinutes;
      final seconds = duration.inSeconds % 60;
      statusText = '${minutes.toString().padLeft(2, '0')}:${seconds.toString().padLeft(2, '0')}';
    } else {
      statusText = _getStatusText(status);
    }

    return Positioned(
      top: 0,
      left: 0,
      right: 0,
      child: Container(
        padding: EdgeInsets.only(
          top: MediaQuery.of(context).padding.top + 16,
          bottom: 16,
          left: 16,
          right: 16,
        ),
        decoration: BoxDecoration(
          gradient: LinearGradient(
            begin: Alignment.topCenter,
            end: Alignment.bottomCenter,
            colors: [
              Colors.black.withOpacity(0.6),
              Colors.transparent,
            ],
          ),
        ),
        child: Row(
          children: [
            IconButton(
              icon: const Icon(Icons.arrow_back, color: Colors.white),
              onPressed: () => Navigator.pop(context),
            ),
            Expanded(
              child: Column(
                children: [
                  Text(
                    session.peerName,
                    style: AppTextStyles.heading6.copyWith(color: Colors.white),
                  ),
                  4.height,
                  Text(
                    statusText,
                    style: AppTextStyles.bodyText2.copyWith(color: Colors.white70),
                  ),
                ],
              ),
            ),
            const SizedBox(width: 48),
          ],
        ),
      ),
    );
  }

  String _getStatusText(CallStatus status) {
    switch (status) {
      case CallStatus.connecting:
        return 'Connecting...';
      case CallStatus.incomingRinging:
        return 'Incoming call...';
      case CallStatus.outgoingRinging:
        return 'Ringing...';
      case CallStatus.connected:
        return 'Connected';
      default:
        return '';
    }
  }

  Widget _buildBottomControls(BuildContext context, CallSession session) {
    final isMuted = _callManager.isMuted;
    final isCameraOn = _callManager.isCameraOn;
    final isSpeakerOn = _callManager.isSpeakerOn;

    return Positioned(
      bottom: 40,
      left: 0,
      right: 0,
      child: Container(
        padding: const EdgeInsets.symmetric(horizontal: 32),
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          children: [
            _buildControlButton(
              icon: isMuted ? Icons.mic_off : Icons.mic,
              label: isMuted ? 'Unmute' : 'Mute',
              onPressed: () => _callManager.toggleMute(),
              backgroundColor: isMuted ? Colors.red : Colors.white24,
            ),
            _buildControlButton(
              icon: isCameraOn ? Icons.videocam : Icons.videocam_off,
              label: isCameraOn ? 'Camera' : 'Camera Off',
              onPressed: () => _callManager.toggleCamera(),
              backgroundColor: isCameraOn ? Colors.white24 : Colors.red,
            ),
            _buildControlButton(
              icon: Icons.cameraswitch,
              label: 'Switch',
              onPressed: () => _callManager.switchCamera(),
              backgroundColor: Colors.white24,
            ),
            _buildControlButton(
              icon: Icons.call_end,
              label: 'End',
              onPressed: () => _callManager.hangUp(),
              backgroundColor: Colors.red,
              iconColor: Colors.white,
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildControlButton({
    required IconData icon,
    required String label,
    required VoidCallback onPressed,
    Color? backgroundColor,
    Color? iconColor,
  }) {
    return Column(
      children: [
        Container(
          padding: const EdgeInsets.all(16),
          decoration: BoxDecoration(
            color: backgroundColor ?? Colors.white24,
            shape: BoxShape.circle,
            border: Border.all(color: Colors.white24),
          ),
          child: Icon(icon, size: 24, color: iconColor ?? Colors.white),
        ).onPress(onPressed),
        8.height,
        Text(
          label,
          style: AppTextStyles.bodyText2.copyWith(color: Colors.white),
        ),
      ],
    );
  }
}