#ifndef AL_MALLOC_H
#define AL_MALLOC_H

#include <algorithm>
#include <cstddef>
#include <iterator>
#include <limits>
#include <memory>
#include <new>
#include <type_traits>
#include <utility>

#include "pragmadefs.h"


void al_free(void *ptr) noexcept;
[[gnu::alloc_align(1), gnu::alloc_size(2), gnu::malloc]]
void *al_malloc(size_t alignment, size_t size);
[[gnu::alloc_align(1), gnu::alloc_size(2), gnu::malloc]]
void *al_calloc(size_t alignment, size_t size);


#define DISABLE_ALLOC()                                                       \
    void *operator new(size_t) = delete;                                      \
    void *operator new[](size_t) = delete;                                    \
    void operator delete(void*) noexcept = delete;                            \
    void operator delete[](void*) noexcept = delete;

#define DEF_NEWDEL(T)                                                         \
    void *operator new(size_t size)                                           \
    {                                                                         \
        static_assert(&operator new == &T::operator new,                      \
            "Incorrect container type specified");                            \
        if(void *ret{al_malloc(alignof(T), size)})                            \
            return ret;                                                       \
        throw std::bad_alloc();                                               \
    }                                                                         \
    void *operator new[](size_t size) { return operator new(size); }          \
    void operator delete(void *block) noexcept { al_free(block); }            \
    void operator delete[](void *block) noexcept { operator delete(block); }

#define DEF_PLACE_NEWDEL()                                                    \
    void *operator new(size_t /*size*/, void *ptr) noexcept { return ptr; }   \
    void *operator new[](size_t /*size*/, void *ptr) noexcept { return ptr; } \
    void operator delete(void *block, void*) noexcept { al_free(block); }     \
    void operator delete(void *block) noexcept { al_free(block); }            \
    void operator delete[](void *block, void*) noexcept { al_free(block); }   \
    void operator delete[](void *block) noexcept { al_free(block); }

enum FamCount : size_t { };

#define DEF_FAM_NEWDEL(T, FamMem)                                             \
    static constexpr size_t Sizeof(size_t count) noexcept                     \
    {                                                                         \
        static_assert(&Sizeof == &T::Sizeof,                                  \
            "Incorrect container type specified");                            \
        return std::max(decltype(FamMem)::Sizeof(count, offsetof(T, FamMem)), \
            sizeof(T));                                                       \
    }                                                                         \
                                                                              \
    void *operator new(size_t /*size*/, FamCount count)                       \
    {                                                                         \
        if(void *ret{al_malloc(alignof(T), T::Sizeof(count))})                \
            return ret;                                                       \
        throw std::bad_alloc();                                               \
    }                                                                         \
    void *operator new[](size_t /*size*/) = delete;                           \
    void operator delete(void *block, FamCount) { al_free(block); }           \
    void operator delete(void *block) noexcept { al_free(block); }            \
    void operator delete[](void* /*block*/) = delete;


namespace al {

template<typename T, std::size_t Align=alignof(T)>
struct allocator {
    static constexpr std::size_t alignment{std::max(Align, alignof(T))};

    using value_type = T;
    using reference = T&;
    using const_reference = const T&;
    using pointer = T*;
    using const_pointer = const T*;
    using size_type = std::size_t;
    using difference_type = std::ptrdiff_t;
    using is_always_equal = std::true_type;

    template<typename U>
    struct rebind {
        using other = allocator<U, Align>;
    };

    constexpr explicit allocator() noexcept = default;
    template<typename U, std::size_t N>
    constexpr explicit allocator(const allocator<U,N>&) noexcept { }

    T *allocate(std::size_t n)
    {
        if(n > std::numeric_limits<std::size_t>::max()/sizeof(T)) throw std::bad_alloc();
        if(auto p = al_malloc(alignment, n*sizeof(T))) return static_cast<T*>(p);
        throw std::bad_alloc();
    }
    void deallocate(T *p, std::size_t) noexcept { al_free(p); }
};
template<typename T, std::size_t N, typename U, std::size_t M>
constexpr bool operator==(const allocator<T,N>&, const allocator<U,M>&) noexcept { return true; }
template<typename T, std::size_t N, typename U, std::size_t M>
constexpr bool operator!=(const allocator<T,N>&, const allocator<U,M>&) noexcept { return false; }


template<typename T>
constexpr T *to_address(T *p) noexcept
{
    static_assert(!std::is_function<T>::value, "Can't be a function type");
    return p;
}

template<typename T>
constexpr auto to_address(const T &p) noexcept
{
    return ::al::to_address(p.operator->());
}


template<typename T, typename ...Args>
constexpr T* construct_at(T *ptr, Args&& ...args)
    noexcept(std::is_nothrow_constructible<T, Args...>::value)
{ return ::new(static_cast<void*>(ptr)) T{std::forward<Args>(args)...}; }

} // namespace al

#endif /* AL_MALLOC_H */