#include <cstdlib>
#include <cstdio>
#include <cassert>
#include <cstring>

template <typename T, size_t growSize = 10, size_t initialSize = 0> class ArrayStack
{
public:
    ArrayStack()
        : 
            m_array(nullptr)
        ,   m_arrayLen(0)
        ,   m_currentHead(0)
        ,   m_growSize(growSize)
    {
        if (initialSize > 0)
        {
            grow(initialSize);
        }
    }

    ~ArrayStack()
    {

    }

    void push(T obj)
    {
        if (m_currentHead+1 >= m_arrayLen)
        {
            grow();
        }

        m_array[m_currentHead] = obj;
        m_currentHead++;
    }

    void pop(T *obj)
    {
        if (m_currentHead > 0)
        {            
            auto temp = m_array[m_currentHead-1];
            *obj = temp;
            m_currentHead--;
        }
        else
        {
            assert(false);
        }
    }


private:
    void    grow(size_t size = growSize)
    {
        // Allocate for the new size
        auto newArrayLen = size + m_arrayLen;
        auto newArray = (T*)malloc(sizeof(T) * newArrayLen);
        
        // Copy over the old array
        if (newArray)
        {
            memcpy(newArray, m_array, m_arrayLen * sizeof(T));
        }

        // delete the old one
        if (m_array) free(m_array);

        // Set the new array
        m_array = newArray;
        m_arrayLen = newArrayLen;
    }
    

    T *m_array;
    size_t m_arrayLen;
    size_t m_currentHead;
    const size_t m_growSize;
};

#ifndef EXTERN_MAIN
int main(int argc, char **argv)
{
    ArrayStack<int> stack;
    const size_t stackSize = 50;

    for (size_t i = 0; i < stackSize; i++)
    {
        stack.push(i);
    }

    for (size_t i = 0; i < stackSize; i++)
    {
        int dest;
        stack.pop(&dest);
        printf("Got: %d\n", dest);
    }

    return 0;
}
#endif