import 'dart:async';
import 'package:dialer/services/obfuscate_service.dart';
import 'package:dialer/widgets/color_darkener.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_contacts/flutter_contacts.dart';
import 'package:intl/intl.dart';
import 'package:permission_handler/permission_handler.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:dialer/features/contacts/contact_state.dart';
import 'package:dialer/widgets/username_color_generator.dart';
import '../../services/block_service.dart';
import '../contacts/widgets/contact_modal.dart';
import '../../services/call_service.dart';

class History {
  final Contact contact;
  final DateTime date;
  final String callType; // 'incoming' or 'outgoing'
  final String callStatus; // 'missed' or 'answered'
  final int attempts;

  History(
    this.contact,
    this.date,
    this.callType,
    this.callStatus,
    this.attempts,
  );
}

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

  @override
  _HistoryPageState createState() => _HistoryPageState();
}

class _HistoryPageState extends State<HistoryPage>
    with AutomaticKeepAliveClientMixin, SingleTickerProviderStateMixin {
  List<History> histories = [];
  bool loading = true;
  int? _expandedIndex;
  final ObfuscateService _obfuscateService = ObfuscateService();
  final CallService _callService = CallService();

  // Create a MethodChannel instance.
  static const MethodChannel _channel = MethodChannel('com.example.calllog');

  @override
  bool get wantKeepAlive => true; // Preserve state when switching pages

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    if (loading && histories.isEmpty) {
      _buildHistories();
    }
  }

  Future<void> _refreshContacts() async {
    final contactState = ContactState.of(context);
    try {
      await contactState.fetchContacts();
    } catch (e) {
      print('Error refreshing contacts: $e');
      ScaffoldMessenger.of(context)
          .showSnackBar(SnackBar(content: Text('Failed to refresh contacts')));
    }
  }

  void _toggleFavorite(Contact contact) async {
    try {
      if (await FlutterContacts.requestPermission()) {
        Contact? fullContact = await FlutterContacts.getContact(contact.id,
            withProperties: true,
            withAccounts: true,
            withPhoto: true,
            withThumbnail: true);

        if (fullContact != null) {
          fullContact.isStarred = !fullContact.isStarred;
          await FlutterContacts.updateContact(fullContact);
        }
        await _refreshContacts();
      } else {
        print("Could not fetch contact details");
      }
    } catch (e) {
      print("Error updating favorite status: $e");
      ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('Failed to update favorite status')));
    }
  }

  /// Helper: Remove all non-digit characters for simple matching.
  String sanitizeNumber(String number) {
    return number.replaceAll(RegExp(r'\D'), '');
  }

  /// Helper: Find a contact from our list by matching phone numbers.
  Contact? findContactForNumber(String number, List<Contact> contacts) {
    final sanitized = sanitizeNumber(number);
    for (var contact in contacts) {
      for (var phone in contact.phones) {
        if (sanitizeNumber(phone.number) == sanitized) {
          return contact;
        }
      }
    }
    return null;
  }

  /// Request permission for reading call logs.
  Future<bool> _requestCallLogPermission() async {
    var status = await Permission.phone.status;
    if (!status.isGranted) {
      status = await Permission.phone.request();
    }
    return status.isGranted;
  }

  /// Build histories from the native call log using the method channel.
  Future<void> _buildHistories() async {
    // Request permission.
    bool hasPermission = await _requestCallLogPermission();
    if (!hasPermission) {
      ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Call log permission not granted')));
      setState(() {
        loading = false;
      });
      return;
    }

    // Retrieve call logs from native code.
    List<dynamic> nativeLogs = [];
    try {
      nativeLogs = await _channel.invokeMethod('getCallLogs');
    } on PlatformException catch (e) {
      print("Error fetching call logs: ${e.message}");
    }

    // Ensure contacts are loaded.
    final contactState = ContactState.of(context);
    if (contactState.loading) {
      await Future.doWhile(() async {
        await Future.delayed(const Duration(milliseconds: 100));
        return contactState.loading;
      });
    }
    List<Contact> contacts = contactState.contacts;

    List<History> callHistories = [];
    // Process each log entry with intermittent yields to avoid freezing.
    for (int i = 0; i < nativeLogs.length; i++) {
      final entry = nativeLogs[i];
      final String number = entry['number'] ?? '';
      if (number.isEmpty) continue;

      // Convert timestamp to DateTime.
      DateTime callDate =
          DateTime.fromMillisecondsSinceEpoch(entry['date'] ?? 0);

      int typeInt = entry['type'] ?? 0;
      int duration = entry['duration'] ?? 0;
      String callType;
      String callStatus;

      // Map integer values to call type/status.
      // Commonly: 1 = incoming, 2 = outgoing, 3 = missed.
      switch (typeInt) {
        case 1:
          callType = "incoming";
          callStatus = (duration == 0) ? "missed" : "answered";
          break;
        case 2:
          callType = "outgoing";
          callStatus = "answered";
          break;
        case 3:
          callType = "incoming";
          callStatus = "missed";
          break;
        default:
          callType = "unknown";
          callStatus = "unknown";
      }

      // Try to find a matching contact.
      Contact? matchedContact = findContactForNumber(number, contacts);
      if (matchedContact == null) {
        // Create a dummy contact if not found.
        matchedContact = Contact(
          id: "dummy-$number",
          displayName: number,
          phones: [Phone(number)],
        );
      }

      callHistories
          .add(History(matchedContact, callDate, callType, callStatus, 1));
      // Yield every 10 iterations to avoid blocking the UI.
      if (i % 10 == 0) await Future.delayed(Duration(milliseconds: 1));
    }

    // Sort histories by most recent.
    callHistories.sort((a, b) => b.date.compareTo(a.date));

    setState(() {
      histories = callHistories;
      loading = false;
    });
  }

  List _buildGroupedList(List<History> historyList) {
    historyList.sort((a, b) => b.date.compareTo(a.date));

    final now = DateTime.now();
    final today = DateTime(now.year, now.month, now.day);
    final yesterday = today.subtract(const Duration(days: 1));

    List<History> todayHistories = [];
    List<History> yesterdayHistories = [];
    List<History> olderHistories = [];

    for (var history in historyList) {
      final callDate =
          DateTime(history.date.year, history.date.month, history.date.day);
      if (callDate == today) {
        todayHistories.add(history);
      } else if (callDate == yesterday) {
        yesterdayHistories.add(history);
      } else {
        olderHistories.add(history);
      }
    }

    final items = <dynamic>[];
    if (todayHistories.isNotEmpty) {
      items.add('Today');
      items.addAll(todayHistories);
    }
    if (yesterdayHistories.isNotEmpty) {
      items.add('Yesterday');
      items.addAll(yesterdayHistories);
    }
    if (olderHistories.isNotEmpty) {
      items.add('Older');
      items.addAll(olderHistories);
    }

    return items;
  }

  /// Returns an icon reflecting call type and status.
  Icon _getCallIcon(History history) {
    IconData iconData;
    Color iconColor;
    if (history.callType == 'incoming') {
      if (history.callStatus == 'missed') {
        iconData = Icons.call_missed;
        iconColor = Colors.red;
      } else {
        iconData = Icons.call_received;
        iconColor = Colors.green;
      }
    } else if (history.callType == 'outgoing') {
      iconData = Icons.call_made;
      iconColor = Colors.green;
    } else {
      iconData = Icons.phone;
      iconColor = Colors.white;
    }
    return Icon(iconData, color: iconColor);
  }

  @override
  Widget build(BuildContext context) {
    super.build(context); // required due to AutomaticKeepAliveClientMixin
    final contactState = ContactState.of(context);

    if (loading || contactState.loading) {
      return Scaffold(
        backgroundColor: Colors.black,
        body: const Center(child: CircularProgressIndicator()),
      );
    }

    if (histories.isEmpty) {
      return Scaffold(
        backgroundColor: Colors.black,
        body: const Center(
          child: Text(
            'No call history available.',
            style: TextStyle(color: Colors.white),
          ),
        ),
      );
    }

    List<History> missedCalls =
        histories.where((h) => h.callStatus == 'missed').toList();

    final allItems = _buildGroupedList(histories);
    final missedItems = _buildGroupedList(missedCalls);

    return DefaultTabController(
      length: 2,
      child: Scaffold(
        backgroundColor: Colors.black,
        appBar: PreferredSize(
          preferredSize: const Size.fromHeight(kToolbarHeight),
          child: Container(
            color: Colors.black,
            child: const TabBar(
              tabs: [
                Tab(text: 'All Calls'),
                Tab(text: 'Missed Calls'),
              ],
              indicatorColor: Colors.white,
            ),
          ),
        ),
        body: TabBarView(
          children: [
            _buildListView(allItems),
            _buildListView(missedItems),
          ],
        ),
      ),
    );
  }

  Widget _buildListView(List items) {
    return ListView.builder(
      itemCount: items.length,
      itemBuilder: (context, index) {
        final item = items[index];
        if (item is String) {
          return Container(
            padding: const EdgeInsets.symmetric(vertical: 8, horizontal: 16),
            color: Colors.grey[900],
            child: Text(
              item,
              style: const TextStyle(
                color: Colors.white70,
                fontWeight: FontWeight.bold,
              ),
            ),
          );
        } else if (item is History) {
          final history = item;
          final contact = history.contact;
          final isExpanded = _expandedIndex == index;
          Color avatarColor = generateColorFromName(contact.displayName);
          return Column(
            children: [
              ListTile(
                leading: GestureDetector(
                  onTap: () {
                    showModalBottomSheet(
                      context: context,
                      isScrollControlled: true,
                      backgroundColor: Colors.transparent,
                      builder: (context) {
                        return ContactModal(
                          contact: contact,
                          onEdit: () async {
                            if (await FlutterContacts.requestPermission()) {
                              final updatedContact =
                                  await FlutterContacts.openExternalEdit(
                                      contact.id);
                              if (updatedContact != null) {
                                await _refreshContacts();
                                Navigator.of(context).pop();
                                ScaffoldMessenger.of(context).showSnackBar(
                                  SnackBar(
                                    content: Text(
                                        '${contact.displayName} updated successfully!'),
                                  ),
                                );
                              } else {
                                ScaffoldMessenger.of(context).showSnackBar(
                                  SnackBar(
                                    content: Text('Edit canceled or failed.'),
                                  ),
                                );
                              }
                            }
                          },
                          onToggleFavorite: () {
                            _toggleFavorite(contact);
                          },
                          isFavorite: contact.isStarred,
                        );
                      },
                    );
                  },
                  child: ObfuscatedAvatar(
                    imageBytes: contact.thumbnail,
                    radius: 25,
                    backgroundColor: avatarColor,
                    fallbackInitial: contact.displayName,
                  ),
                ),
                title: Text(
                  _obfuscateService.obfuscateData(contact.displayName),
                  style: const TextStyle(color: Colors.white),
                ),
                subtitle: Text(
                  DateFormat('MMM dd, hh:mm a').format(history.date),
                  style: const TextStyle(color: Colors.grey),
                ),
                trailing: Row(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    _getCallIcon(history),
                    const SizedBox(width: 8),
                    Text(
                      '${history.attempts}x',
                      style: const TextStyle(color: Colors.white),
                    ),
                    IconButton(
                      icon: const Icon(Icons.phone, color: Colors.green),
                      onPressed: () async {
                        if (contact.phones.isNotEmpty) {
                          _callService.makeGsmCall(context, phoneNumber: contact.phones.first.number);
                        } else {
                          ScaffoldMessenger.of(context).showSnackBar(
                            const SnackBar(
                                content: Text('Contact has no phone number')),
                          );
                        }
                      },
                    ),
                  ],
                ),
                onTap: () {
                  setState(() {
                    _expandedIndex = isExpanded ? null : index;
                  });
                },
              ),
              if (isExpanded)
                Container(
                  color: Colors.grey[850],
                  child: FutureBuilder<bool>(
                    future: BlockService().isNumberBlocked(
                        contact.phones.isNotEmpty
                            ? contact.phones.first.number
                            : ''),
                    builder: (context, snapshot) {
                      final isBlocked = snapshot.data ?? false;
                      return Row(
                        mainAxisAlignment: MainAxisAlignment.spaceAround,
                        children: [
                          TextButton.icon(
                            onPressed: () async {
                              if (history.contact.phones.isNotEmpty) {
                                final Uri smsUri = Uri(
                                    scheme: 'sms',
                                    path: history.contact.phones.first.number);
                                if (await canLaunchUrl(smsUri)) {
                                  await launchUrl(smsUri);
                                } else {
                                  ScaffoldMessenger.of(context).showSnackBar(
                                    const SnackBar(
                                        content:
                                            Text('Could not send message')),
                                  );
                                }
                              } else {
                                ScaffoldMessenger.of(context).showSnackBar(
                                  const SnackBar(
                                      content:
                                          Text('Contact has no phone number')),
                                );
                              }
                            },
                            icon:
                                const Icon(Icons.message, color: Colors.white),
                            label: const Text('Message',
                                style: TextStyle(color: Colors.white)),
                          ),
                          TextButton.icon(
                            onPressed: () {
                              Navigator.push(
                                context,
                                MaterialPageRoute(
                                  builder: (_) =>
                                      CallDetailsPage(history: history),
                                ),
                              );
                            },
                            icon: const Icon(Icons.info, color: Colors.white),
                            label: const Text('Details',
                                style: TextStyle(color: Colors.white)),
                          ),
                          TextButton.icon(
                            onPressed: () async {
                              final phoneNumber = contact.phones.isNotEmpty
                                  ? contact.phones.first.number
                                  : null;
                              if (phoneNumber == null) {
                                ScaffoldMessenger.of(context).showSnackBar(
                                  const SnackBar(
                                      content:
                                          Text('Contact has no phone number')),
                                );
                                return;
                              }
                              if (isBlocked) {
                                await BlockService().unblockNumber(phoneNumber);
                                ScaffoldMessenger.of(context).showSnackBar(
                                  SnackBar(
                                      content: Text('$phoneNumber unblocked')),
                                );
                              } else {
                                await BlockService().blockNumber(phoneNumber);
                                ScaffoldMessenger.of(context).showSnackBar(
                                  SnackBar(
                                      content: Text('$phoneNumber blocked')),
                                );
                              }
                              setState(() {});
                            },
                            icon: Icon(
                                isBlocked ? Icons.lock_open : Icons.block,
                                color: Colors.white),
                            label: Text(isBlocked ? 'Unblock' : 'Block',
                                style: const TextStyle(color: Colors.white)),
                          ),
                        ],
                      );
                    },
                  ),
                ),
            ],
          );
        }
        return const SizedBox.shrink();
      },
    );
  }
}

class CallDetailsPage extends StatelessWidget {
  final History history;
  final ObfuscateService _obfuscateService = ObfuscateService();

  CallDetailsPage({super.key, required this.history});

  @override
  Widget build(BuildContext context) {
    final contact = history.contact;
    final contactBg = generateColorFromName(contact.displayName);
    final contactLetter = darken(contactBg);

    return Scaffold(
      backgroundColor: Colors.black,
      appBar: AppBar(
        title: const Text('Call Details'),
        backgroundColor: Colors.black,
      ),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          children: [
            // Display Contact Name and Thumbnail.
            Row(
              children: [
                (contact.thumbnail != null && contact.thumbnail!.isNotEmpty)
                    ? ObfuscatedAvatar(
                        imageBytes: contact.thumbnail,
                        radius: 30,
                        backgroundColor: contactBg,
                        fallbackInitial: contact.displayName,
                      )
                    : CircleAvatar(
                        backgroundColor:
                            generateColorFromName(contact.displayName),
                        radius: 30,
                        child: Text(
                          contact.displayName.isNotEmpty
                              ? contact.displayName[0].toUpperCase()
                              : '?',
                          style: TextStyle(color: contactLetter),
                        ),
                      ),
                const SizedBox(width: 16),
                Expanded(
                  child: Text(
                    _obfuscateService.obfuscateData(contact.displayName),
                    style: const TextStyle(color: Colors.white, fontSize: 24),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 24),
            // Display call details.
            DetailRow(
              label: 'Call Type:',
              value: history.callType,
            ),
            DetailRow(
              label: 'Call Status:',
              value: history.callStatus,
            ),
            DetailRow(
              label: 'Date:',
              value: DateFormat('MMM dd, yyyy - hh:mm a').format(history.date),
            ),
            DetailRow(
              label: 'Attempts:',
              value: '${history.attempts}',
            ),
            const SizedBox(height: 24),
            if (contact.phones.isNotEmpty)
              DetailRow(
                label: 'Number:',
                value: _obfuscateService
                    .obfuscateData(contact.phones.first.number),
              ),
          ],
        ),
      ),
    );
  }
}

class DetailRow extends StatelessWidget {
  final String label;
  final String value;

  const DetailRow({Key? key, required this.label, required this.value})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 8.0),
      child: Row(
        children: [
          Text(
            label,
            style: const TextStyle(
                color: Colors.white70, fontWeight: FontWeight.bold),
          ),
          const SizedBox(width: 8),
          Expanded(
            child: Text(
              value,
              style: const TextStyle(color: Colors.white),
              textAlign: TextAlign.right,
            ),
          ),
        ],
      ),
    );
  }
}