#ifndef MALACHSCRIPT_MEMORYPOOL_HPP
#define MALACHSCRIPT_MEMORYPOOL_HPP

#include <cstddef>
#include <cstdint>
#include <stdexcept>

namespace MalachScript::Utils {
    template <size_t steps> class MemoryPool {
    public:
        MemoryPool() { AllocateBlock(); }
        MemoryPool(MemoryPool const&) = delete;
        MemoryPool& operator=(MemoryPool const&) = delete;

        ~MemoryPool() {
            for (auto c : _chunks) {
                free(c);
            }
        }

        template <class T, class... parameters> T* Create(parameters... args) {
            auto* p = _tail + sizeof(T);
            if (p >= _end) {
                AllocateBlock();
                p = _tail + sizeof(T);
            }
            auto* element = new (_tail) T(args...);
            _tail = p;
            return element;
        }

    private:
        std::vector<uint8_t*> _chunks;

        uint8_t* _tail = nullptr;
        uint8_t* _end;
        uint8_t* _head = nullptr;

        void AllocateBlock() {
            auto* newPtr = malloc(steps * sizeof(uint8_t*));
            if (newPtr == nullptr) {
                throw std::logic_error("Out of memory.");
            }
            _tail = _head = static_cast<uint8_t*>(newPtr);
            _end = _head + (steps * sizeof(uint8_t*));
            _chunks.push_back(_head);
        }
    };
}

#endif // MALACHSCRIPT_MEMORYPOOL_HPP