Queue.h

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/*
 * Copyright (C) 2019 Niek Linnenbank
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
#ifndef __LIBSTD_QUEUE_H
#define __LIBSTD_QUEUE_H
 
#include "Types.h"
#include "Macros.h"
#include "Container.h"
 
template <class T, Size N> class Queue : public Container
{
  public:
 
    Queue()
    {
        clear();
    }
 
    bool push(const T & item)
    {
        if (m_count >= N)
        {
            return false;
        }
 
        m_array[m_head] = item;
        m_head = (m_head + 1) % N;
        m_count++;
 
        return true;
    }
 
    T & pop()
    {
        uint idx = m_tail;
        m_tail = (m_tail + 1) % N;
        m_count--;
 
        return m_array[idx];
    }
 
    bool contains(const T & item) const
    {
        for (Size i = 0; i < m_count; i++)
        {
            if (m_array[(m_tail + i) % N] == item)
                return true;
        }
 
        return false;
    }
 
    Size remove(T value)
    {
        const Size numItems = m_count;
        Size numRemoved = 0;
 
        for (Size i = 0; i < numItems; i++)
        {
            T & item = pop();
 
            if (item != value)
                push(item);
            else
                numRemoved++;
        }
 
        return numRemoved;
    }
 
    virtual void clear()
    {
        m_head = 0;
        m_tail = 0;
        m_count = 0;
    }
 
    virtual Size size() const
    {
        return N;
    }
 
    virtual Size count() const
    {
        return m_count;
    }
 
  private:
 
    T m_array[N];
 
    uint m_head;
 
    uint m_tail;
 
    uint m_count;
};
 
#endif /* __LIBSTD_QUEUE_H */