///
/// Copyright (c) 2016-2022 Sensus Slovensko a.s.
///
using System;
using System.Collections.Generic;
using System.Windows.Forms;
using Common;
using Users.Entities;

namespace Users
{
    class UserAndForm
    {
        public readonly User User;
        public readonly Form Form;

        public UserAndForm(User user, Form form)
        {
            User = user;
            Form = form;
        }
    }

    public class CurrentUser
    {
		public static DBSettings RemoteUsersDB = null;
		public static DBSettings LocalUsersDB = null;


        static readonly Stack<UserAndForm> userStack = new Stack<UserAndForm>();

        public static AuthorizedAs AuthorizedAs;
        public static DateTime LastAuthorization = DateTime.Now;

        public static int MinPasswdLength = 0;
        public static int PasswdExpirationPeriodDays = 0;


        /// <summary>
        /// Push a new user into the stack of users and form references.
        /// Prevent double user stack entry for the same Windows form.
        /// </summary>
        /// <param name="newUser">New user</param>
        /// <param name="currentForm">Reference to the current form</param>
        public static void Change(User newUser, Form currentForm)
        {
            if (userStack.Count > 0 && userStack.Peek().Form == currentForm)
            {
                userStack.Pop();
            }

            userStack.Push(new UserAndForm(newUser, currentForm));
        }

        /// <summary>
        /// Restore an original user from the stack of users - remove user at the top of the stack.
        /// Prevent restoring when there is no entry for the form currently being closed.
        /// </summary>
        /// <param name="formBeingClosed">Reference to the form currently being closed</param>
        /// <returns>true = current user was restored, false = no current user change</returns>
        public static bool Restore(Form formBeingClosed)
        {
            if (userStack.Count > 0 && userStack.Peek().Form == formBeingClosed)
            {
                userStack.Pop();
                return true;
            }

            return false;
        }

        /// <summary>
        /// Return the user currenty at the top of the stack of users.
        /// </summary>
        public static User User()
        {
            return (userStack.Count > 0) ? userStack.Peek().User : null;    /// TODO: Return default user when stack is empty
        }

        /// <summary>
        /// Return the current user name or an empty string
        /// </summary>
        public static string UserName()
        {
            return (User() != null) ? User().UserName : string.Empty;
        }

        /// <summary>
        /// Return the current user number or 0
        /// </summary>
        public static int Number()
        {
            return (User() != null) ? User().Number : 0;
        }

        public static bool IsPowerUser()
        {
            return (User() != null) ? User().IsPowerUser() : false;
        }

        public static bool IsMemberOf(GID groupId)
        {
            return (User() != null) ? User().IsMemberOf(groupId) : false;
        }

        public static bool IsMemberOf(GID[] groupIds)
        {
            return (User() != null) ? User().IsMemberOf(groupIds) : (groupIds == null);
        }
    }
}