import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:get/get.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import '../../core/services/chit_group_service.dart';
import '../../core/models/chit_group.dart';
import '../../core/themes/draw_slot_theme.dart';
import '../../shared/widgets/draw_animation_selector.dart';
import '../../core/utils/whatsapp_util.dart';

class DrawAnimationPage extends StatefulWidget {
  final ChitGroup group;
  final int month;
  final int year;
  final String serverSeed;
  final int nonce;
  final List<Map<String, dynamic>> eligibleMembers;
  
  const DrawAnimationPage({
    super.key,
    required this.group,
    required this.month,
    required this.year,
    required this.serverSeed,
    required this.nonce,
    required this.eligibleMembers,
  });

  @override
  State<DrawAnimationPage> createState() => _DrawAnimationPageState();
}

class _DrawAnimationPageState extends State<DrawAnimationPage>
    with SingleTickerProviderStateMixin {
  late AnimationController _fadeController;
  late Animation<double> _fadeAnimation;
  bool _isComplete = false;
  /// True after the draw is successfully persisted (safe to leave without prompt).
  bool _drawRecorded = false;
  /// Single client seed for the whole page so animation + API save use the same value.
  late final String _animationClientSeed;

  void _exitDrawScreen({required bool recorded}) {
    if (!mounted) return;
    Navigator.of(context).pop(recorded);
  }

  /// System back / header — always offers a way out.
  Future<void> _handleLeaveIntent() async {
    if (!_isComplete) {
      final cancel = await showDialog<bool>(
        context: context,
        builder: (ctx) => AlertDialog(
          title: const Text('Cancel draw?'),
          content: const Text(
            'The draw is still in progress. Stop and go back?',
          ),
          actions: [
            TextButton(
              onPressed: () => Navigator.pop(ctx, false),
              child: const Text('Keep drawing'),
            ),
            FilledButton(
              onPressed: () => Navigator.pop(ctx, true),
              style: FilledButton.styleFrom(
                backgroundColor: Colors.red.shade700,
                foregroundColor: Colors.white,
              ),
              child: const Text('Stop'),
            ),
          ],
        ),
      );
      if (cancel == true && mounted) {
        _exitDrawScreen(recorded: false);
      }
      return;
    }

    if (_drawRecorded) {
      _exitDrawScreen(recorded: true);
      return;
    }

    final leave = await showDialog<bool>(
      context: context,
      builder: (ctx) => AlertDialog(
        title: const Text('Leave without saving?'),
        content: const Text(
          'This winner is not recorded yet. If you leave now, you will need to run the draw again.',
        ),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(ctx, false),
            child: const Text('Stay'),
          ),
          FilledButton(
            onPressed: () => Navigator.pop(ctx, true),
            style: FilledButton.styleFrom(
              backgroundColor: Colors.red.shade700,
              foregroundColor: Colors.white,
            ),
            child: const Text('Leave anyway'),
          ),
        ],
      ),
    );
    if (leave == true && mounted) {
      _exitDrawScreen(recorded: false);
    }
  }

  @override
  void initState() {
    super.initState();
    _animationClientSeed = 'DRAW_${DateTime.now().millisecondsSinceEpoch}';
    
    _fadeController = AnimationController(
      duration: const Duration(milliseconds: 800),
      vsync: this,
    );
    
    _fadeAnimation = Tween<double>(
      begin: 0.0,
      end: 1.0,
    ).animate(CurvedAnimation(
      parent: _fadeController,
      curve: Curves.easeInOut,
    ));
    
    _fadeController.forward();
  }

  @override
  void dispose() {
    _fadeController.dispose();
    super.dispose();
  }

  void _onDrawComplete(String winnerId) async {
    if (_isComplete) return;
    
    setState(() {
      _isComplete = true;
    });

    // Let the slot settle on the winner before the confirmation sheet
    await Future.delayed(const Duration(milliseconds: 900));
    
    // Find winner (avoid firstWhere/orElse RTI mismatch Map<String,String> vs dynamic on web)
    Map<String, dynamic> winner = {'name': 'Unknown', 'mobile': ''};
    for (final raw in widget.eligibleMembers) {
      final m = Map<String, dynamic>.from(raw);
      if ('${m['id']}' == '$winnerId') {
        winner = m;
        break;
      }
    }
    
    // Get the bid amount for this month from financial data
    final chitGroupService = Get.find<ChitGroupService>();
    await chitGroupService.loadGroupFinancialData(widget.group.id);
    
    // Find the financial data for this specific month
    final monthNames = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
    final monthKey = '${monthNames[widget.month - 1]}-${widget.year.toString().substring(2)}';
    
    final financialEntry = chitGroupService.financialData.firstWhereOrNull(
      (entry) => entry.monthYear == monthKey,
    );
    
    final bidAmount = financialEntry?.bidAmount ?? widget.group.monthlyInstallment;
    
    // Show confirmation dialog with winner and bid amount
    final shouldSave = await _showWinnerConfirmation(winner, bidAmount);
    
    if (shouldSave == true) {
      await _saveDrawResult(winnerId, bidAmount);
    } else {
      _exitDrawScreen(recorded: false);
    }
  }
  
  Future<bool?> _showWinnerConfirmation(Map<String, dynamic> winner, double bidAmount) async {
    await HapticFeedback.mediumImpact();
    final monthNames = [
      'January', 'February', 'March', 'April', 'May', 'June',
      'July', 'August', 'September', 'October', 'November', 'December',
    ];
    final periodLabel =
        '${monthNames[widget.month - 1]} ${widget.year} · ${widget.group.name}';

    return showDialog<bool>(
      context: context,
      barrierDismissible: false,
      builder: (dialogContext) => TweenAnimationBuilder<double>(
        tween: Tween(begin: 0.88, end: 1.0),
        duration: const Duration(milliseconds: 420),
        curve: Curves.easeOutCubic,
        builder: (context, scale, child) =>
            Transform.scale(scale: scale, child: child),
        child: AlertDialog(
          insetPadding: EdgeInsets.symmetric(horizontal: 20.w, vertical: 24.h),
          backgroundColor: Colors.white,
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(20.r),
          ),
          title: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Row(
                children: [
                  Container(
                    padding: EdgeInsets.all(10.w),
                    decoration: BoxDecoration(
                      color: Colors.amber.shade50,
                      shape: BoxShape.circle,
                    ),
                    child: Icon(
                      Icons.emoji_events_rounded,
                      color: Colors.amber.shade800,
                      size: 28.w,
                    ),
                  ),
                  SizedBox(width: 12.w),
                  Expanded(
                    child: Text(
                      'Winner',
                      style: TextStyle(
                        fontSize: 22.sp,
                        fontWeight: FontWeight.w800,
                        color: Colors.grey.shade900,
                        letterSpacing: -0.5,
                      ),
                    ),
                  ),
                  IconButton(
                    tooltip: 'Close',
                    onPressed: () => Navigator.pop(dialogContext, false),
                    icon: Icon(Icons.close, color: Colors.grey.shade700),
                  ),
                ],
              ),
              SizedBox(height: 8.h),
              Text(
                periodLabel,
                style: TextStyle(
                  fontSize: 12.sp,
                  fontWeight: FontWeight.w500,
                  color: Colors.grey.shade600,
                  height: 1.3,
                ),
              ),
            ],
          ),
          content: SingleChildScrollView(
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                Container(
                  width: double.infinity,
                  padding: EdgeInsets.symmetric(horizontal: 18.w, vertical: 22.h),
                  decoration: BoxDecoration(
                    gradient: LinearGradient(
                      begin: Alignment.topLeft,
                      end: Alignment.bottomRight,
                      colors: [
                        Colors.green.shade50,
                        Colors.teal.shade50.withOpacity(0.85),
                      ],
                    ),
                    borderRadius: BorderRadius.circular(16.r),
                    border: Border.all(color: Colors.green.shade200, width: 1.5),
                  ),
                  child: Column(
                    children: [
                      Text(
                        winner['name']?.toString() ?? 'Unknown',
                        style: TextStyle(
                          fontSize: 26.sp,
                          fontWeight: FontWeight.w800,
                          color: Colors.green.shade900,
                          height: 1.15,
                        ),
                        textAlign: TextAlign.center,
                      ),
                      if ((winner['mobile']?.toString() ?? '').isNotEmpty) ...[
                        SizedBox(height: 10.h),
                        Text(
                          winner['mobile']?.toString() ?? '',
                          style: TextStyle(
                            fontSize: 15.sp,
                            color: Colors.grey.shade700,
                            fontWeight: FontWeight.w500,
                          ),
                          textAlign: TextAlign.center,
                        ),
                      ],
                      SizedBox(height: 18.h),
                      Container(
                        height: 1,
                        color: Colors.green.shade200.withOpacity(0.9),
                      ),
                      SizedBox(height: 14.h),
                      Text(
                        'Prize amount',
                        style: TextStyle(
                          fontSize: 13.sp,
                          color: Colors.grey.shade600,
                          fontWeight: FontWeight.w600,
                          letterSpacing: 0.3,
                        ),
                      ),
                      SizedBox(height: 6.h),
                      Text(
                        _formatIndianCurrency(bidAmount),
                        style: TextStyle(
                          fontSize: 30.sp,
                          fontWeight: FontWeight.w800,
                          color: Colors.green.shade800,
                        ),
                      ),
                    ],
                  ),
                ),
                SizedBox(height: 16.h),
                Row(
                  children: [
                    Expanded(
                      child: OutlinedButton.icon(
                        onPressed: () => _shareViaWhatsApp(winner, bidAmount),
                        icon: Icon(Icons.send_rounded,
                            size: 18.w, color: const Color(0xFF25D366)),
                        label: Text(
                          'Share',
                          style: TextStyle(
                              fontSize: 13.sp, color: const Color(0xFF25D366)),
                        ),
                        style: OutlinedButton.styleFrom(
                          padding: EdgeInsets.symmetric(vertical: 12.h),
                          side: const BorderSide(color: Color(0xFF25D366)),
                        ),
                      ),
                    ),
                    SizedBox(width: 8.w),
                    Expanded(
                      child: OutlinedButton.icon(
                        onPressed: () {
                          Get.snackbar(
                            'Screenshot',
                            'Capture this screen if you want a local copy.',
                            backgroundColor: Colors.blue.shade700,
                            colorText: Colors.white,
                            duration: const Duration(seconds: 3),
                          );
                        },
                        icon: Icon(Icons.photo_camera_outlined,
                            size: 18.w, color: Colors.blue.shade700),
                        label: Text(
                          'Capture',
                          style: TextStyle(
                              fontSize: 13.sp, color: Colors.blue.shade700),
                        ),
                        style: OutlinedButton.styleFrom(
                          padding: EdgeInsets.symmetric(vertical: 12.h),
                          side: BorderSide(color: Colors.blue.shade700),
                        ),
                      ),
                    ),
                  ],
                ),
                SizedBox(height: 12.h),
                Text(
                  'Save to record this result and get a shareable public link.',
                  style: TextStyle(
                    fontSize: 14.sp,
                    color: Colors.grey.shade700,
                    fontWeight: FontWeight.w500,
                    height: 1.35,
                  ),
                  textAlign: TextAlign.center,
                ),
              ],
            ),
          ),
          actionsPadding: EdgeInsets.fromLTRB(20.w, 0, 20.w, 16.h),
          actions: [
            Row(
              children: [
                Expanded(
                  child: OutlinedButton(
                    onPressed: () => Navigator.pop(dialogContext, false),
                    style: OutlinedButton.styleFrom(
                      padding: EdgeInsets.symmetric(vertical: 14.h),
                      side: BorderSide(color: Colors.grey.shade400),
                    ),
                    child: Text(
                      'Discard',
                      style: TextStyle(
                        fontSize: 15.sp,
                        fontWeight: FontWeight.w600,
                        color: Colors.grey.shade800,
                      ),
                    ),
                  ),
                ),
                SizedBox(width: 10.w),
                Expanded(
                  flex: 2,
                  child: FilledButton.icon(
                    onPressed: () => Navigator.pop(dialogContext, true),
                    style: FilledButton.styleFrom(
                      backgroundColor: Colors.green.shade700,
                      foregroundColor: Colors.white,
                      padding: EdgeInsets.symmetric(vertical: 14.h),
                    ),
                    icon: Icon(Icons.check_circle_outline, size: 20.w),
                    label: Text(
                      'Save result',
                      style: TextStyle(
                        fontSize: 15.sp,
                        fontWeight: FontWeight.w700,
                      ),
                    ),
                  ),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
  
  void _shareViaWhatsApp(Map<String, dynamic> winner, double bidAmount) {
    final monthNames = ['January', 'February', 'March', 'April', 'May', 'June', 
                        'July', 'August', 'September', 'October', 'November', 'December'];
    final monthName = monthNames[widget.month - 1];
    
    final message = '''
🎉 *${widget.group.name}* 🎉

📅 *Monthly Draw Result*
Month: $monthName ${widget.year}

🏆 *WINNER*
${winner['name']}
${winner['mobile']}

💰 *Prize Amount*
${_formatIndianCurrency(bidAmount)}

✨ This draw was conducted using our provably fair system for complete transparency.

_Congratulations to the winner!_
    ''';
    
    // Share to all members or specific number
    WhatsAppUtil.shareText(message);
  }
  
  Future<void> _saveDrawResult(String winnerId, double bidAmount) async {
    final chitGroupService = Get.find<ChitGroupService>();
    
    try {
      // Show loading
      Get.dialog(
        PopScope(
          canPop: false,
          child: Center(
            child: Container(
              padding: EdgeInsets.all(32.w),
              decoration: BoxDecoration(
                color: Colors.white,
                borderRadius: BorderRadius.circular(16.r),
              ),
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  CircularProgressIndicator(),
                  SizedBox(height: 16.h),
                  Text(
                    'Saving draw result...',
                    style: TextStyle(fontSize: 16.sp),
                  ),
                ],
              ),
            ),
          ),
        ),
        barrierDismissible: false,
      );
      
      final created = await chitGroupService.createMonthlyDraw(
        widget.group.id,
        widget.month,
        widget.year,
        clientSeed: _animationClientSeed,
        prizeAmount: bidAmount,
        animationWinnerUserId: winnerId,
        serverSeed: widget.serverSeed,
        nonce: widget.nonce,
      );

      if (!mounted) return;
      Get.back();

      if (created == null) {
        Get.snackbar(
          'Error',
          'Failed to save draw result',
          backgroundColor: Colors.red,
          colorText: Colors.white,
          duration: const Duration(seconds: 4),
          snackPosition: SnackPosition.TOP,
        );
        return;
      }

      setState(() {
        _drawRecorded = true;
      });

      final drawId = created['id']?.toString();
      if (drawId != null) {
        final publicUrl = await WhatsAppUtil.getDrawPublicShareUrl(drawId);
        if (mounted && publicUrl != null && publicUrl.isNotEmpty) {
          await _showPublicResultLinkDialog(publicUrl);
        } else if (mounted && (publicUrl == null || publicUrl.isEmpty)) {
          Get.snackbar(
            'Draw saved',
            'Public link unavailable — set PUBLIC_BASE_URL on the server to share results.',
            backgroundColor: Colors.orange.shade700,
            colorText: Colors.white,
            duration: const Duration(seconds: 5),
            snackPosition: SnackPosition.TOP,
          );
        }
      }

      if (!mounted) return;
      _exitDrawScreen(recorded: true);

      Get.snackbar(
        'Draw Saved! 🎉',
        'Winner has been recorded. Share the public link so anyone can view results.',
        backgroundColor: Colors.green,
        colorText: Colors.white,
        duration: const Duration(seconds: 3),
        snackPosition: SnackPosition.TOP,
      );
    } catch (e) {
      if (mounted) {
        try {
          Get.back();
        } catch (_) {}
      }

      if (mounted) {
        Get.snackbar(
          'Error',
          'Failed to save draw result: ${e.toString()}',
          backgroundColor: Colors.red,
          colorText: Colors.white,
          duration: const Duration(seconds: 4),
        );
      }
    }
  }

  Future<void> _showPublicResultLinkDialog(String url) async {
    await showDialog<void>(
      context: context,
      barrierDismissible: true,
      builder: (ctx) => AlertDialog(
        title: Row(
          children: [
            Expanded(child: const Text('Public result link')),
            IconButton(
              tooltip: 'Close',
              onPressed: () => Navigator.of(ctx).pop(),
              icon: const Icon(Icons.close),
            ),
          ],
        ),
        content: SingleChildScrollView(
          child: SelectableText(
            url,
            style: TextStyle(fontSize: 13.sp),
          ),
        ),
        actions: [
          TextButton(
            onPressed: () async {
              await Clipboard.setData(ClipboardData(text: url));
              if (ctx.mounted) {
                Get.snackbar(
                  'Copied',
                  'Link copied — anyone can open it in a browser',
                  snackPosition: SnackPosition.BOTTOM,
                  duration: const Duration(seconds: 3),
                );
              }
            },
            child: const Text('Copy only'),
          ),
          FilledButton(
            onPressed: () => Navigator.of(ctx).pop(),
            child: const Text('Done'),
          ),
        ],
      ),
    );
  }

  String _formatIndianCurrency(double amount) {
    int intAmount = amount.round();
    String amountStr = intAmount.toString();
    String formatted = '';
    
    if (amountStr.length <= 3) {
      formatted = amountStr;
    } else {
      int remaining = amountStr.length;
      int start = 0;
      
      if (remaining > 3) {
        formatted = amountStr.substring(amountStr.length - 3);
        remaining -= 3;
        start = amountStr.length - 3;
      } else {
        formatted = amountStr;
        remaining = 0;
      }
      
      while (remaining > 0) {
        int groupSize = remaining >= 2 ? 2 : remaining;
        int groupStart = start - groupSize;
        String group = amountStr.substring(groupStart, start);
        formatted = group + ',' + formatted;
        start = groupStart;
        remaining -= groupSize;
      }
    }
    
    return '₹$formatted';
  }

  @override
  Widget build(BuildContext context) {
    const monthLabels = [
      'Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun',
      'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec',
    ];
    final drawPeriodShort =
        '${monthLabels[widget.month - 1]} ${widget.year}';
    final theme = Theme.of(context);
    final d = DrawSlotTheming(theme.colorScheme, theme.brightness);

    return PopScope(
      canPop: false,
      onPopInvokedWithResult: (didPop, result) async {
        if (didPop || !mounted) return;
        await _handleLeaveIntent();
      },
      child: Scaffold(
        backgroundColor: Colors.transparent,
        body: SafeArea(
          child: FadeTransition(
            opacity: _fadeAnimation,
            child: Container(
              width: double.infinity,
              height: double.infinity,
              decoration: BoxDecoration(
                gradient: d.pageBackdrop,
              ),
              child: Column(
                children: [
                  // Header
                  Padding(
                    padding: EdgeInsets.fromLTRB(8.w, 12.h, 12.w, 8.h),
                    child: Column(
                      children: [
                        Row(
                          children: [
                            IconButton(
                              tooltip: _drawRecorded
                                  ? 'Done'
                                  : (_isComplete
                                      ? 'Close'
                                      : 'Cancel draw'),
                              icon: Icon(
                                _drawRecorded
                                    ? Icons.check_circle_outline_rounded
                                    : Icons.close_rounded,
                                color: d.pageOnText,
                                size: 28.w,
                              ),
                              onPressed: () => _handleLeaveIntent(),
                            ),
                            Expanded(
                              child: Column(
                                children: [
                                  Text(
                                    widget.group.name,
                                    style: theme.textTheme.headlineSmall?.copyWith(
                                      color: d.pageOnText,
                                      fontWeight: FontWeight.w800,
                                      letterSpacing: -0.3,
                                    ),
                                    textAlign: TextAlign.center,
                                    maxLines: 2,
                                    overflow: TextOverflow.ellipsis,
                                  ),
                                  SizedBox(height: 10.h),
                                  Container(
                                    padding: EdgeInsets.symmetric(
                                      horizontal: 14.w,
                                      vertical: 8.h,
                                    ),
                                    decoration: BoxDecoration(
                                      color: d.chipFill,
                                      borderRadius: BorderRadius.circular(20.r),
                                      border: Border.all(color: d.chipBorder),
                                    ),
                                    child: Text(
                                      drawPeriodShort,
                                      style: theme.textTheme.labelLarge?.copyWith(
                                        color: d.pageOnText,
                                        fontWeight: FontWeight.w600,
                                        letterSpacing: 0.2,
                                      ),
                                    ),
                                  ),
                                ],
                              ),
                            ),
                            SizedBox(width: 48.w),
                          ],
                        ),
                      ],
                    ),
                  ),
                  
                  // Animation Area - Scrollable
                  Expanded(
                    child: SingleChildScrollView(
                      padding: EdgeInsets.symmetric(horizontal: 16.w, vertical: 20.h),
                      child: DrawAnimationSelector(
                        members: widget.eligibleMembers,
                        onDrawComplete: _onDrawComplete,
                        serverSeed: widget.serverSeed,
                        clientSeed: _animationClientSeed,
                        nonce: widget.nonce,
                        animationDuration: const Duration(seconds: 8),
                        allowReplay: !_isComplete,
                      ),
                    ),
                  ),
                  
                  // Footer
                  Padding(
                    padding: EdgeInsets.fromLTRB(20.w, 8.h, 20.w, 16.h),
                    child: Column(
                      children: [
                        Container(
                          padding: EdgeInsets.symmetric(
                            horizontal: 12.w,
                            vertical: 14.h,
                          ),
                          decoration: BoxDecoration(
                            color: d.chipFill,
                            borderRadius: BorderRadius.circular(18.r),
                            border: Border.all(color: d.chipBorder),
                          ),
                          child: Row(
                            mainAxisAlignment: MainAxisAlignment.spaceAround,
                            children: [
                              _buildInfoItem(
                                d,
                                'In this draw',
                                '${widget.eligibleMembers.length}',
                                Icons.how_to_reg_rounded,
                              ),
                              Container(
                                width: 1,
                                height: 36.h,
                                color: d.chipBorder.withOpacity(0.6),
                              ),
                              _buildInfoItem(
                                d,
                                'Group size',
                                '${widget.group.maxMembers}',
                                Icons.groups_rounded,
                              ),
                            ],
                          ),
                        ),
                        SizedBox(height: 14.h),
                        Row(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: [
                            Icon(
                              Icons.verified_user_rounded,
                              size: 16.w,
                              color: theme.colorScheme.tertiary,
                            ),
                            SizedBox(width: 8.w),
                            Text(
                              'Provably fair · transparent draw',
                              style: theme.textTheme.bodyMedium?.copyWith(
                                color: d.pageMuted,
                                fontWeight: FontWeight.w600,
                              ),
                            ),
                          ],
                        ),
                      ],
                    ),
                  ),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }

  Widget _buildInfoItem(
    DrawSlotTheming d,
    String label,
    String value,
    IconData icon,
  ) {
    return Column(
      children: [
        Icon(
          icon,
          color: d.pageMuted,
          size: 22.w,
        ),
        SizedBox(height: 6.h),
        Text(
          value,
          style: TextStyle(
            fontSize: 20.sp,
            fontWeight: FontWeight.w800,
            color: d.pageOnText,
          ),
        ),
        Text(
          label,
          style: TextStyle(
            fontSize: 11.sp,
            fontWeight: FontWeight.w600,
            color: d.pageMuted,
            letterSpacing: 0.2,
          ),
        ),
      ],
    );
  }
}