#include <new>
#include "apothecary.h"
#include <cassert>
#include <cstddef>

using namespace std;

Apothecary::Apothecary() : backPtr(NULL), frontPtr(NULL)
{
}

Apothecary::Apothecary(const Apothecary& Apoth)
{
}

Apothecary::~Apothecary()
{
    while (!isEmpty())
        dequeue();
    assert ((backPtr == NULL) && (frontPtr == NULL));
}

bool Apothecary::isEmpty() const
{
    return backPtr == NULL;
}

void Apothecary::enqueue(const potionType& newPotion) throw(QueueException)
{
    try
    {
        StoreNode *newPtr = new StoreNode;

        newPtr ->potion = newPotion

            newPtr ->next = NULL;

        if(isEmpty())
            frontPtr = newPtr;
        else
            backPtr -> next = newPtr;

        backPtr = newPtr;
    }
    catch (bad_alloc e)
    {
        throw QueueException("QueueException: enqueue cannot allocate memory.");
    }
}

void Apothecary::dequeue() throw(QueueException)
{
    if (isEmpty())
        throw QueueException(
        "QueueException: empty queue, cannot dequeue");

    else
    {
        StoreNode *tempPtr = frontPtr;
        if(frontPtr == backPtr)
        {
            frontPtr = NULL;
            backPtr = NULL;
        }
        else
            frontPtr = frontPtr->next;
            tempPtr->next = NULL;
            delete tempPtr;
        }
}

void Apothecary::dequeue(potionType& storeFront)
                        throw(QueueException)
{
    if (isEmpty())
        throw QueueException( "QueueException: empty Queue, cannot dequeue");
    else
    {
        queueFront = frontPtr -> potion;
        dequeue();
    }
}

void Apothecary::getFront(potionType& storeFront) const
                            throw(QueueException)
{
    if (isEmpty())
        throw QueueException("QueueException: empty queue, cannot getFront");
    else
        storeFront = frontPtr->potion;
}