import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/material.dart';
import 'package:intl/intl.dart';

class AllActivityScreen extends StatelessWidget {
  const AllActivityScreen({super.key});

  Future<Map<String, Map<String, double>>> fetchWeeklySummary() async {
    final user = FirebaseAuth.instance.currentUser;
    if (user == null) return {};

    final snapshot = await FirebaseFirestore.instance.collection('activities').get();
    final Map<String, Map<String, double>> weeklyData = {};

    final allDays = ['Senin', 'Selasa', 'Rabu', 'Kamis', 'Jumat', 'Sabtu', 'Minggu'];

    for (var doc in snapshot.docs) {
      final data = doc.data()['data'];
      if (data == null || data['userId'] != user.uid) continue;

      final timestamp = (data['timestamp'] as Timestamp?)?.toDate();
      if (timestamp == null) continue;

      final weekStart = DateTime(timestamp.year, timestamp.month, timestamp.day)
          .subtract(Duration(days: timestamp.weekday - 1));
      final weekKey = DateFormat('dd MMM yyyy').format(weekStart);

      final hari = DateFormat('EEEE', 'id_ID').format(timestamp);
      final jarak = (data['jarak'] ?? 0).toDouble();
      final satuan = data['satuan'] ?? 'M';
      final jarakKm = satuan == 'M' ? jarak / 1000.0 : jarak;

      weeklyData.putIfAbsent(weekKey, () => {
        for (var day in allDays) day: 0.0
      });

      weeklyData[weekKey]![hari] = (weeklyData[weekKey]![hari] ?? 0) + jarakKm;
    }

    return weeklyData;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white,
      appBar: AppBar(
        title: const Text("View All Weeks", style: TextStyle(color: Colors.white),),
        automaticallyImplyLeading: true,
        backgroundColor: Colors.blueAccent,
        iconTheme: const IconThemeData(color: Colors.white),
      ),
      body: FutureBuilder<Map<String, Map<String, double>>>(
        future: fetchWeeklySummary(),
        builder: (context, snapshot) {
          if (snapshot.connectionState == ConnectionState.waiting) {
            return const Center(child: CircularProgressIndicator());
          }

          final data = snapshot.data ?? {};
          if (data.isEmpty) {
            return const Center(child: Text("Belum ada data aktivitas lari."));
          }

          final sortedWeeks = data.keys.toList()
            ..sort((a, b) => DateFormat('dd MMM yyyy').parse(b).compareTo(DateFormat('dd MMM yyyy').parse(a)));

          return ListView.builder(
            itemCount: sortedWeeks.length,
            padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 12),
            itemBuilder: (context, index) {
              final week = sortedWeeks[index];
              final daysData = data[week]!;
              final totalKm = daysData.values.fold(0.0, (a, b) => a + b);

              return Card(
                color: Colors.white,
                elevation: 3,
                shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(16)),
                margin: const EdgeInsets.only(bottom: 16),
                child: Padding(
                  padding: const EdgeInsets.all(16),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          const Icon(Icons.calendar_today, size: 20, color: Colors.blue),
                          const SizedBox(width: 8),
                          Text(
                            'Minggu dimulai: $week',
                            style: const TextStyle(fontSize: 16, fontWeight: FontWeight.bold),
                          ),
                        ],
                      ),
                      const SizedBox(height: 12),
                      Column(
                        children: daysData.entries.map((entry) {
                          return Padding(
                            padding: const EdgeInsets.symmetric(vertical: 2),
                            child: Row(
                              mainAxisAlignment: MainAxisAlignment.spaceBetween,
                              children: [
                                Text(entry.key, style: const TextStyle(fontSize: 14)),
                                Text('${entry.value.toStringAsFixed(2)} KM',
                                    style: const TextStyle(fontSize: 14, fontWeight: FontWeight.w500)),
                              ],
                            ),
                          );
                        }).toList(),
                      ),
                      const Divider(height: 24, thickness: 1),
                      Row(
                        mainAxisAlignment: MainAxisAlignment.end,
                        children: [
                          const Icon(Icons.directions_run, size: 18, color: Colors.green),
                          const SizedBox(width: 6),
                          Text(
                            'Total: ${totalKm.toStringAsFixed(2)} KM',
                            style: const TextStyle(fontWeight: FontWeight.w600),
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
              );
            },
          );
        },
      ),
    );
  }
}