public void LoadUsers(List<String> Users)
{
//We use this boolean to know when to spend computational time to do group management over again
Boolean ChangeInUsers = false;
List<Notification> TempNotifications = new List<Notification>();
//Since these lists are sorted we can make use of
//techniques that will enhance the efficiency of the history traversal
Users.Sort();
int count = ActiveUsers.Count;
for (int i = 0; i < count; i++)
{
User user = ActiveUsers[i];
if (user is Guest)
{
ActiveUsers.RemoveAt(i);
i--;
count = ActiveUsers.Count;
}
}
NumberOfGuests = 0;
Groups[0].NumberOfUsers = NumberOfGuests;
//If the list of active users are empty
// then just create one where all the users present are added
if (HistoryMatrix.Count == 0)
{
foreach (String id in Users)
{
User cur;
if (id.Equals("Guest"))
{
cur = new Guest();
NumberOfGuests++;
Groups[0].NumberOfUsers = NumberOfGuests;
TempNotifications.Add(new Notification("New guest detected.", 2));
}
else
{
cur = new RegisteredUser();
cur.Load(id);
ChangeInUsers = true;
String Name = ((RegisteredUser)cur).FullName;
int type;
if (((RegisteredUser)cur).Gender.Equals("Female"))
type = 0;
else
type = 2;
TempNotifications.Add(new Notification("Registered user detected.", type));
//TempNotifications.Add(new Notification(Name +" detected.", type));
}
ActiveUsers.Add(cur);
}
}
// otherwise if the list is not empty we remove users that are no longer present
// and add users that are new to the list
else
{
Boolean temp;
temp = AddToList(Users, TempNotifications);
if (temp)
{
ChangeInUsers = true;
temp = false;
}
temp = PruneList(Users, TempNotifications);
if (temp)
ChangeInUsers = true;
}
HistoryMatrix.Add(Users);
// if the history count is more than 5 (which means that 600ms*5 = every 3 seconds)
// the oldest part of the list needs to be forgotten
// I changed this to 10 instead of 5 which is perhaps better
if (HistoryMatrix.Count > 10)
{
HistoryMatrix.RemoveAt(0);
}
// the management of the active users will be complete at this point
// this is where group management comes into play
if (ChangeInUsers)
{
foreach (User user in ActiveUsers)
{
if (user is RegisteredUser)
{
String SQL = String.Format("SELECT GroupID FROM UserGroup WHERE UserID = '{0}';", ((RegisteredUser)user).UserID);
try
{
DataTable DT = OcDBLink.getDataTable(SQL);
for (int x = 0; x < DT.Rows.Count; x++)
{
DataRow curRow = DT.Rows[x];
String groupID = curRow.ItemArray[0].ToString();
Boolean found = false;
foreach (Group group in Groups)
{
if (group.GroupID.Equals(groupID))
{
found = true;
group.NumberOfUsers++;
ChangeInGroups = true;
}
}
if (!found)
{
Group cur = new Group(groupID);
cur.NumberOfUsers++;
Groups.Add(cur);
ChangeInGroups = true;
}
}
}
catch { }
}
}
}
int counter = 0;
Boolean newGuest = false;
for (int i = 0; i < TempNotifications.Count; i++)
{
if (TempNotifications[i].Type != 3)
{
counter++;
}
else
{
if (!newGuest)
{
Notifications.Enqueue(TempNotifications[i]);
newGuest = true;
}
TempNotifications.RemoveAt(i);
}
}
if (counter > 3)
Notifications.Enqueue(new Notification("Group of users detected.", 1));
else
for (int i = 0; i < TempNotifications.Count; i++)
Notifications.Enqueue(TempNotifications[i]);
}
private Boolean AddToList(List<String> Users, List<Notification> TempNotifications)
{
Boolean Return = false;
// To add to a list first we need to be sure the user is not already in the list
// Then ascertain if the person was detected atleast once before (this will be used to improve the accuracy of the users being selected)
foreach (String newUser in Users)
{
Boolean CanAdd = true;
// because the list is sorted, it is plausible to do the binary search method.
// but this method will not be used because it only becomes more efficient than linear search after a certain size
// the list's sizes are too small for it to make a significant impact
foreach (User u in ActiveUsers)
{
if (u is RegisteredUser)
{
RegisteredUser user = (RegisteredUser)u;
if (user.UserID.Equals(newUser))
{
CanAdd = false;
break;
}
}
}
if (CanAdd)
{
foreach (String user in HistoryMatrix[HistoryMatrix.Count - 1])
{
if (user.Equals(newUser))
{
User cur;
if (user.Equals("Guest"))
{
cur = new Guest();
NumberOfGuests++;
Groups[0].NumberOfUsers = NumberOfGuests;
TempNotifications.Add(new Notification("New guest detected.", 2));
}
else
{
cur = new RegisteredUser();
cur.Load(user);
Return = true;
String Name = ((RegisteredUser)cur).FullName;
int type;
if (((RegisteredUser)cur).Gender.Equals("Female"))
type = 0;
else
type = 2;
TempNotifications.Add(new Notification("Registered user detected.", type));
//TempNotifications.Add(new Notification(Name + " detected.", type));
}
ActiveUsers.Add(cur);
break;
}
}
}
}
return Return;
}