import 'package:flutter/material.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import 'package:smpn1_lengkong/core/constants/app_colors.dart';
import 'package:smpn1_lengkong/core/models/student_model.dart';
import 'package:smpn1_lengkong/core/routes/app_routes.dart';
import 'package:smpn1_lengkong/core/service/student_service.dart';
import 'package:smpn1_lengkong/main.dart';

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

  @override
  State<NotificationScreen> createState() => _NotificationScreenState();
}

class _NotificationScreenState extends State<NotificationScreen> {
  late Future<List<Map<String, dynamic>>> _notificationsFuture;
  late StudentModel student;
  bool _isInitialized = false;

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    if (!_isInitialized) {
      student = ModalRoute.of(context)!.settings.arguments as StudentModel;
      _notificationsFuture = StudentService().getNotifications(
        student.id,
        student.className,
      );
      _isInitialized = true;
    }
  }

  Future<void> _refreshData() async {
    setState(() {
      _notificationsFuture = StudentService().getNotifications(
        student.id,
        student.className,
      );
    });
    await _notificationsFuture;
  }

  Future<void> _handleReadAll() async {
    await StudentService().markAllAsRead(student.id, student.className);
    await _refreshData();
    if (mounted) {}
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: AppColors.backgroundWhite,
      appBar: AppBar(
        title: Text(
          "Pemberitahuan Kelas ${student.className}",
          style: const TextStyle(color: Colors.white),
        ),
        backgroundColor: AppColors.primaryBlue,
        foregroundColor: Colors.white,
        elevation: 0,
      ),
      body: RefreshIndicator(
        onRefresh: _refreshData,
        color: AppColors.primaryBlue,
        child: FutureBuilder<List<Map<String, dynamic>>>(
          future: _notificationsFuture,
          builder: (context, snapshot) {
            if (snapshot.connectionState == ConnectionState.waiting) {
              return const Center(child: CircularProgressIndicator());
            }

            if (snapshot.hasError) {
              return Center(
                child: Text("Terjadi kesalahan: ${snapshot.error}"),
              );
            }

            // Ambil data dan lakukan pengurutan (Sorting)
            final List<Map<String, dynamic>> notifications =
                snapshot.data ?? [];

            if (notifications.isNotEmpty) {
              notifications.sort((a, b) {
                // Parsing tanggal, berikan fallback waktu sekarang jika null/error
                DateTime dateA =
                    DateTime.tryParse(a['tanggal']?.toString() ?? '') ??
                    DateTime.now();
                DateTime dateB =
                    DateTime.tryParse(b['tanggal']?.toString() ?? '') ??
                    DateTime.now();

                // b.compareTo(a) untuk urutan descending (Terbaru -> Terlama)
                return dateB.compareTo(dateA);
              });
            }

            final int unreadCount =
                notifications.where((n) => n['status'] == 'unread').length;

            if (notifications.isEmpty) {
              return Stack(
                children: [
                  _buildEmptyState(),
                  ListView(physics: const AlwaysScrollableScrollPhysics()),
                ],
              );
            }

            return CustomScrollView(
              physics: const AlwaysScrollableScrollPhysics(
                parent: BouncingScrollPhysics(),
              ),
              slivers: [
                SliverToBoxAdapter(
                  child: Padding(
                    padding: EdgeInsets.fromLTRB(20.w, 24.h, 20.w, 16.h),
                    child: Row(
                      mainAxisAlignment: MainAxisAlignment.spaceBetween,
                      crossAxisAlignment: CrossAxisAlignment.end,
                      children: [
                        Column(
                          crossAxisAlignment: CrossAxisAlignment.start,
                          children: [
                            Text(
                              unreadCount > 0
                                  ? "Anda memiliki $unreadCount pemberitahuan baru"
                                  : "Semua pemberitahuan sudah diperiksa",
                              style: TextStyle(
                                fontSize: 13.sp,
                                color: AppColors.textSecondary,
                              ),
                            ),
                          ],
                        ),
                        if (unreadCount > 0)
                          GestureDetector(
                            onTap: _handleReadAll,
                            child: Container(
                              padding: EdgeInsets.symmetric(
                                horizontal: 12.w,
                                vertical: 8.h,
                              ),
                              decoration: BoxDecoration(
                                color: AppColors.primaryBlue.withOpacity(0.08),
                                borderRadius: BorderRadius.circular(10.r),
                              ),
                              child: Text(
                                "Baca Semua",
                                style: TextStyle(
                                  color: AppColors.primaryBlue,
                                  fontWeight: FontWeight.bold,
                                  fontSize: 12.sp,
                                ),
                              ),
                            ),
                          ),
                      ],
                    ),
                  ),
                ),
                SliverPadding(
                  padding: EdgeInsets.symmetric(horizontal: 20.w),
                  sliver: SliverList(
                    delegate: SliverChildBuilderDelegate((context, index) {
                      final item = notifications[index];
                      return Padding(
                        padding: EdgeInsets.only(bottom: 12.h),
                        child: _buildNotificationCard(context, item),
                      );
                    }, childCount: notifications.length),
                  ),
                ),
                SliverToBoxAdapter(child: SizedBox(height: 30.h)),
              ],
            );
          },
        ),
      ),
    );
  }

  Widget _buildNotificationCard(
    BuildContext context,
    Map<String, dynamic> item,
  ) {
    final bool isUnread = item['status'] == 'unread';

    return InkWell(
      onTap: () async {
        if (isUnread) {
          await StudentService().markNotificationAsRead(item['id']);
          await _refreshData();
        }

        // Gunakan navigatorKey sebagai pengganti Navigator.pushNamed(context, ...)
        navigatorKey.currentState?.pushNamed(
          AppRoutes.notificationDetail,
          arguments: {
            'title': item['title'] ?? 'Pengumuman',
            'body': item['body'] ?? '',
            'date': item['tanggal'] ?? '',
          },
        );
      },
      borderRadius: BorderRadius.circular(16.r),
      child: Container(
        padding: EdgeInsets.all(16.w),
        decoration: BoxDecoration(
          color: Colors.white,
          borderRadius: BorderRadius.circular(16.r),
          border: Border.all(
            color:
                isUnread
                    ? AppColors.primaryBlue.withOpacity(0.3)
                    : Colors.grey.shade100,
            width: isUnread ? 1.5 : 1,
          ),
          boxShadow: [
            BoxShadow(
              color: Colors.black.withOpacity(0.02),
              blurRadius: 10,
              offset: const Offset(0, 4),
            ),
          ],
        ),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Container(
              padding: EdgeInsets.all(12.w),
              decoration: BoxDecoration(
                color:
                    isUnread
                        ? AppColors.primaryBlue.withOpacity(0.1)
                        : Colors.grey.shade50,
                borderRadius: BorderRadius.circular(12.r),
              ),
              child: Icon(
                Icons.notifications_active_outlined,
                color: isUnread ? AppColors.primaryBlue : Colors.grey.shade400,
                size: 24.sp,
              ),
            ),
            SizedBox(width: 16.w),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Expanded(
                        child: Text(
                          item['title'] ?? '-',
                          maxLines: 1,
                          overflow: TextOverflow.ellipsis,
                          style: TextStyle(
                            fontWeight:
                                isUnread ? FontWeight.w800 : FontWeight.w600,
                            fontSize: 15.sp,
                            color: AppColors.textPrimary,
                          ),
                        ),
                      ),
                      if (isUnread)
                        Container(
                          width: 8.w,
                          height: 8.w,
                          decoration: const BoxDecoration(
                            color: AppColors.dangerRed,
                            shape: BoxShape.circle,
                          ),
                        ),
                    ],
                  ),
                  SizedBox(height: 4.h),
                  Text(
                    item['body'] ?? '-',
                    maxLines: 2,
                    overflow: TextOverflow.ellipsis,
                    style: TextStyle(
                      color: isUnread ? Colors.black87 : Colors.grey.shade600,
                      fontSize: 13.sp,
                      height: 1.5,
                    ),
                  ),
                  SizedBox(height: 10.h),
                  Row(
                    children: [
                      Icon(
                        Icons.access_time_rounded,
                        size: 12.sp,
                        color: Colors.grey,
                      ),
                      SizedBox(width: 4.w),
                      Text(
                        item['tanggal']?.toString().length == 16
                            ? item['tanggal']
                            : (item['tanggal']?.toString().substring(0, 16) ??
                                ''),
                        style: TextStyle(
                          fontSize: 11.sp,
                          color: Colors.grey,
                          fontWeight: FontWeight.w500,
                        ),
                      ),
                    ],
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildEmptyState() {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(
            Icons.notifications_none_rounded,
            size: 60.sp,
            color: Colors.grey.shade300,
          ),
          SizedBox(height: 16.h),
          Text(
            "Belum Ada Notifikasi",
            style: TextStyle(color: Colors.grey.shade500),
          ),
        ],
      ),
    );
  }
}