#pragma once

#include "EHS.h"
#include "Log.h"
#include "Link.h"

namespace lwe
{
    template<typename T, typename N = UInt_64>
    class LinkedList
    {
    private:
        Link<T>* start;
        Link<T>* end;
        N size;

    public:
        ~LinkedList()
        {
            delete start;
        }

        LinkedList()
            : size(0), start(nullptr), end(nullptr)
        {
        }

        LinkedList(const LinkedList& list)
            : start(nullptr), end(nullptr), size(list.size)
        {
            const Link<T>* rLast = list.start;
            Link<T>* last = new Link<T>(rLast->value);
            start = last;

            while (rLast->child)
            {
                last->child = new Link<T>(rLast->child->value);
                last = last->child;
                rLast = rLast->child;
            }

            end = last;
        }

        LinkedList(LinkedList&& list) noexcept
            : start(list.start), end(list.end), size(list.size)
        {
            list.start = nullptr;
            list.end = nullptr;
            list.size = {};
        }

        LinkedList& operator=(const LinkedList& list)
        {
            if (this == &list)
                return *this;

            const Link<T>* rLast = list.start;
            Link<T>* last = new Link<T>(rLast->value);
            start = last;

            while (rLast->child)
            {
                last->child = new Link<T>(rLast->child->value);
                last = last->child;
                rLast = rLast->child;
            }

            end = last;
            size = list.size;

            return *this;
        }

        LinkedList& operator=(LinkedList&& list) noexcept
        {
            if (this == &list)
                return *this;

            start = list.start;
            end = list.end;
            size = list.size;

            list.start = nullptr;
            list.end = nullptr;
            list.size = {};

            return *this;
        }

        const Link<T>* operator[](const N index) const
        {
            const Link<T>* result = start;

            for (N i = 0; i != index; ++i)
                result = result->child;

            return result;
        }

        Link<T>* operator[](const N index)
        {
            Link<T>* result = start;

            for (N i = 0; i != index; ++i)
                result = result->child;

            return result;
        }

        T& Insert(const N index, const T value)
        {
            if (index && index == size - 1)
            {
                end->child = new Link<T>(value);
                end = end->child;
                ++size;
                return end->value;
            }
            else if (index)
            {
                Link<T>* hierarchy = start;
                for (N i = 0; i != index - 1; ++i)
                    hierarchy = hierarchy->child;

                hierarchy->child = new Link<T>(value, hierarchy->child);
                ++size;
                return hierarchy->child->value;
            }
            else
            {
                start = new Link<T>(value, start);
                ++size;
                return start->value;
            }
        }

        T Remove(const N index)
        {
            if (index && index == size - 1)
            {
                Link<T>* hierarchy = start;
                while (hierarchy->child->child)
                    hierarchy = hierarchy->child;

                T result = end->value;
                delete end;
                end = hierarchy;
                --size;
                return result;
            }
            else if (index)
            {
                Link<T>* hierarchy = start;
                for (N i = 0; i != index - 1; ++i)
                    hierarchy = hierarchy->child;

                Link<T>* tmp = hierarchy->child;
                T result = tmp->value;
                hierarchy->child = hierarchy->child->child;
                tmp->child = nullptr;
                delete tmp;
                return result;
            }
            else
            {
                Link<T>* tmp = start;
                T result = tmp->value;
                start = start->child;

                if (--size)
                    tmp->child = nullptr;
                else
                    end = nullptr;

                delete tmp;

                return result;
            }
        }

        T& Push(const T value)
        {
            if (size)
            {
                end->child = new Link<T>(value);
                end = end->child;
                ++size;
                return end->value;
            }
            else
            {
                start = new Link<T>(value);
                end = start;
                size = 1;
                return start->value;
            }
        }

        T Pop()
        {
            if (size == 1)
            {
                T result = start->value;
                delete start;
                start = nullptr;
                end = nullptr;
                size = 0;
                return result;
            }
            if (size > 1)
            {
                Link<T>* hierarchy = start;
                while (hierarchy->child->child)
                    hierarchy = hierarchy->child;

                T result = hierarchy->child->value;
                delete hierarchy->child;
                hierarchy->child = nullptr;
                end = hierarchy;
                return result;
            }
            else
                return {};
        }

        void Clear()
        {
            delete start;
            start = nullptr;
            end = nullptr;
            size = 0;
        }

        N Size() const
        {
            return size;
        }
    };
}