/// <summary>
/// Takes the first pet of the prefered type out of the shelter
/// </summary>
/// <param name="prefered">A Pet of the type that will be returned</param>
/// <returns>A Pet depending on the type of prefered Pet passed in</returns>
public Pet Dequeue(Pet preferred)
{
Pet result = null;
Pet temp = null;
if (preferred.GetType() == Front.GetType())
{
result = Dequeue();
}
else
{
temp = Dequeue();
Enqueue(temp);
while (Front != temp)
{
if ((Front.GetType() == preferred.GetType()) && (result == null))
{
result = Dequeue();
}
else
{
Enqueue(Dequeue());
}
}
}
if (result == null)
{
result = Dequeue();
}
return(result);
}
/// <summary>
/// dequeues the first of the animal entered as "pref", else dequeues any dog or cat at the front
/// </summary>
/// <param name="pref">the type of animal to dequeue</param>
/// <returns>the dequeued animal</returns>
public Animal Dequeue(string pref)
{
string fPref = pref.ToLower();
string frontType = Front.GetType().Name.ToLower();
if ((fPref != "cat" && fPref != "dog") || frontType == fPref)
{
Console.WriteLine($"Dequeueing a {Front.GetType().Name.ToLower()}");
return(Dequeue());
}
Animal oldFront = Front;
// handles a single animal and no match
if (fPref != frontType && Front == Rear)
{
Console.WriteLine($"There's only one animal in the shelter," +
$" and it's not a {fPref}.");
return(null);
}
while (frontType != fPref)
{
Enqueue(Dequeue());
if (Front == oldFront)
{
Console.WriteLine("That animal cannot be found here.");
return(null);
}
frontType = Front.GetType().Name.ToLower();
}
Console.WriteLine($"Dequeueing a {frontType}");
Animal tmp1 = Dequeue();
// loop to ensure the shelter is in proper order before returning
// the desired cat or dog
while (Front != oldFront)
{
Enqueue(Dequeue());
}
return(tmp1);
}