BufferFunctions.h

/*--------------------------------------------------------------------------------------------
Copyright (c) 2019, NDEVR LLC
tyler.parke@ndevr.org
  __    __   ____     _____ __     __  _______
 |  \  |  | |  __ \  |  ___|\ \   / / |   __  \
 |   \ |  | | |  \ \ | |___  \ \ / /  |  |__)  |
 |  . \|  | | |__/ / | |___   \ V /   |   _   /
 |  |\    |_|_____/__|_____|___\_/____|  | \  \
 |__| \__________________________________|  \__\
 
Subject to the terms of the Enterprise+ Agreement, NDEVR hereby grants 
Licensee a limited, non-exclusive, non-transferable, royalty-free license 
(without the right to sublicense) to use the API solely for the purpose of 
Licensee's internal development efforts to develop applications for which 
the API was provided.
 
The above copyright notice and this permission notice shall be included in all 
copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
 
Library: Base
File: BufferFunctions
Included in API: True
Author(s): Tyler Parke
 *-----------------------------------------------------------------------------------------**/
#pragma once
#include <NDEVR/Buffer.h>
#include <algorithm>
namespace NDEVR
{
    class BufferFunctions
    {};

    template <class t_type, class t_buffer>
    class BufferInsertIterator
    {
    protected:
        t_buffer* m_container; 
        uint04 m_location; 
    public:
        using iterator_category = std::random_access_iterator_tag; 
        using value_type = t_type; 
        using difference_type = ptrdiff_t; 
        using pointer = t_type*; 
        using reference = t_type&; 

        explicit BufferInsertIterator(t_buffer& container, int i)
            : m_container(&container)
            , m_location(i)
        {}

        BufferInsertIterator<t_type, t_buffer>& operator=(const t_type& value)
        {
            m_container->add(m_location, value);
            ++m_location;
            return *this;
        }

        BufferInsertIterator<t_type, t_buffer>& operator=(t_type&& value)
        {
            m_container->add(m_location, std::move(value));
            ++m_location;
            return *this;
        }

        BufferInsertIterator<t_type, t_buffer>& operator++ ()
        {
            m_location++;
            m_location = getMin(m_location, m_container->size());
            lib_assert(m_location <= m_container->size(), "iterator going off edge");
            return *this;
        }

        BufferInsertIterator<t_type, t_buffer>& operator++(int val)
        {
            m_location += cast<uint04>(val);
            m_location = getMin(m_location, m_container->size());
            lib_assert(m_location <= m_container->size(), "iterator going off edge");
            return *this;
        }

        BufferInsertIterator<t_type, t_buffer>& operator*()
        {
            return *this;
        }

        const BufferInsertIterator<t_type, t_buffer>& operator*() const
        {
            return *this;
        }
    };

    template<class t_type, class t_memory_manager>
    Buffer<t_type, t_memory_manager> IntersectSorted(const Buffer<t_type, t_memory_manager>& a, const Buffer<t_type, t_memory_manager>& b)
    {
        Buffer<t_type, t_memory_manager> intersect_buf = a;
        BufferInsertIterator<t_type, Buffer<t_type, t_memory_manager>> iter(intersect_buf, 0);
        auto final_iter = std::set_intersection(a.begin(), a.end(), b.begin(), b.end(), iter);
        intersect_buf.setSize(cast<uint04>(final_iter - intersect_buf.begin()));
        return intersect_buf;
    }

    template<class t_type, class t_memory_manager>
    Buffer<t_type, t_memory_manager> ExceptSorted(const Buffer<t_type, t_memory_manager>& a, const Buffer<t_type, t_memory_manager>& b)
    {
        lib_assert(a.isSorted(), "A is not sorted");
        lib_assert(b.isSorted(), "B is not sorted");
        if (b.size() == 0)
            return a;
        if (a.size() == 0)
            return Buffer<t_type, t_memory_manager>();
        Buffer<t_type, t_memory_manager> intersect_buf;
        BufferInsertIterator<t_type, Buffer<t_type, t_memory_manager>> iter(intersect_buf, 0);
        std::set_difference(a.begin(), a.end(), b.begin(), b.end(), iter);
        return intersect_buf;
    }

    template<class t_type, class t_memory_manager>
    Buffer<t_type, t_memory_manager> Union(const Buffer<t_type, t_memory_manager>& a, const Buffer<t_type, t_memory_manager>& b)
    {
        Buffer<t_type, t_memory_manager> union_buf(a.size() + b.size());
        union_buf.addAll(a);
        union_buf.addAll(b);
        union_buf.makeUnique();
        return union_buf;
    }

    template<class t_type, class t_memory_manager>
    Buffer<t_type, t_memory_manager> Intersect(const Buffer<t_type, t_memory_manager>& a, const Buffer<t_type, t_memory_manager>& b)
    {
        Buffer<t_type, t_memory_manager> a_sorted = a;
        Buffer<t_type, t_memory_manager> b_sorted = b;
        a_sorted.sort();
        b_sorted.sort();
        a_sorted.setUniquePresorted();
        b_sorted.setUniquePresorted();
        return IntersectSorted(a_sorted, b_sorted);
    }

    template<class t_type, class t_memory_manager>
    Buffer<t_type, t_memory_manager> IntersectPreserveOrderA(const Buffer<t_type, t_memory_manager>& a, const Buffer<t_type, t_memory_manager>& b)
    {
        Buffer<t_type, t_memory_manager> intersect_buf = a;
        for (uint04 i = a.size() - 1; IsValid(i); i--)
        {
            if (!b.contains(a[i]))
                intersect_buf.removeIndex(i);
        }
        return intersect_buf;
    }

    template<class t_type, class t_memory_manager>
    Buffer<t_type, t_memory_manager> Except(const Buffer<t_type, t_memory_manager>& a, const Buffer<t_type, t_memory_manager>& b)
    {
        Buffer<t_type, t_memory_manager> a_sorted = a;
        Buffer<t_type, t_memory_manager> b_sorted = b;
        a_sorted.sort();
        b_sorted.sort();
        a_sorted.setUniquePresorted();
        b_sorted.setUniquePresorted();
        return ExceptSorted(a_sorted, b_sorted);
    }
 
    
    
}