import 'dart:async';

import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:fcs/data/services/services.dart';
import 'package:fcs/domain/constants.dart';
import 'package:fcs/domain/entities/user.dart';
import 'package:fcs/domain/vo/privilege.dart';
import 'package:fcs/helpers/firebase_helper.dart';
import 'package:fcs/pages/main/model/base_model.dart';
import 'package:logging/logging.dart';

class StaffModel extends BaseModel {
  final log = Logger('StaffModel');
  StreamSubscription<QuerySnapshot>? listener;
  StreamSubscription<QuerySnapshot>? privilegeListener;

  List<User> employees = [];
  List<Privilege> privileges = [];

  @override
  void privilegeChanged() {
    super.privilegeChanged();
    _loadPrivileges();
    _loadEmployees();
  }

  @override
  logout() async {
    if (listener != null) listener!.cancel();
    if (privilegeListener != null) privilegeListener!.cancel();
    employees = [];
    privileges = [];
  }

  Future<void> _loadEmployees() async {
    if (user == null || !user!.hasStaffs()) throw "No Privilege";

    try {
      if (listener != null) listener!.cancel();

      listener = FirebaseFirestore.instance
          .collection("/$user_collection")
          .where("is_employee", isEqualTo: true)
          .where("is_sys_admin", isEqualTo: false)
          .snapshots()
          .listen((QuerySnapshot snapshot) {
        employees.clear();
        employees = snapshot.docs.map((documentSnapshot) {
          var user = User.fromMap(
              documentSnapshot.data() as Map<String, dynamic>,
              documentSnapshot.id);
          return user;
        }).toList();
        notifyListeners();
      });
    } catch (e) {
      log.warning("Error!! $e");
    }
  }

  Future<void> _loadPrivileges() async {
    try {
      privilegeListener = FirebaseFirestore.instance
          .collection("/$privilege_collection")
          .snapshots()
          .listen((QuerySnapshot snapshot) {
        privileges.clear();
        privileges = snapshot.docs.map((documentSnapshot) {
          var privilege = Privilege.fromMap(
              documentSnapshot.data() as Map<String, dynamic>,
              documentSnapshot.id);
          return privilege;
        }).toList();
        notifyListeners();
      });
    } catch (e) {
      log.warning("Error!! $e");
    }
  }

  Future<void> updatePrivileges(String userID, List<String> privileges) async {
    await request("/employee/privileges", "PUT",
        payload: {"id": userID, "privileges": privileges},
        token: await getToken());
  }

  Future<User?> findUser(String phoneNumber) {
    return Services.instance.userService.findUser(phoneNumber);
  }

  Future<List<User>> getPickupEmployees() async {
    if (user == null || !user!.hasShipment()) return [];
    return _getUsers(privilege_shipment);
  }

  Future<List<User>> _getUsers(String privilege) async {
    List<User> users = [];
    try {
      var snaps = await FirebaseFirestore.instance
          .collection("/$user_collection")
          .where("is_employee", isEqualTo: true)
          .where("is_sys_admin", isEqualTo: false)
          .where("privileges", arrayContains: privilege)
          .get(const GetOptions(source: Source.server));
      users = snaps.docs.map((documentSnapshot) {
        var user = User.fromMap(
            documentSnapshot.data as Map<String, dynamic>, documentSnapshot.id);
        return user;
      }).toList();
    } catch (e) {
      log.warning("Error!! $e");
    }
    return users;
  }
}