Kylin/DataStructure/CircularDoublyLinkedList.h

#ifndef DUALCIRCULARLIST_H
#define DUALCIRCULARLIST_H

#include "DoublyLinkedList.h"

namespace Kylin {
template <typename T>
class CircularDoublyLinkedList : public DoublyLinkedList<T> {
    using Node = typename DoublyLinkedList<T>::Node;
    using Iterator = typename DoublyLinkedList<T>::Iterator;

public:
    static constexpr size_t npos = static_cast<size_t>(-1);
    CircularDoublyLinkedList() {
        this->m_header.next = reinterpret_cast<Node *>(&(this->m_header));
        this->m_header.prev = reinterpret_cast<Node *>(&(this->m_header));
        this->m_last = reinterpret_cast<Node *>(&this->m_header);
    }

    CircularDoublyLinkedList(std::initializer_list<T> init) {
        this->m_header.next = reinterpret_cast<Node *>(&(this->m_header));
        this->m_header.prev = reinterpret_cast<Node *>(&(this->m_header));
        this->m_last = reinterpret_cast<Node *>(&this->m_header);
        for (auto &value : init) append(value);
    }

    CircularDoublyLinkedList(const CircularDoublyLinkedList &other) {
        this->m_header.next = reinterpret_cast<Node *>(&(this->m_header));
        this->m_header.prev = reinterpret_cast<Node *>(&(this->m_header));
        this->m_last = reinterpret_cast<Node *>(&this->m_header);

        auto sourceNode = other.m_header.next;
        auto targetNode = reinterpret_cast<Node *>(&this->m_header);

        for (size_t i = 0; i < other.m_size; i++) {
            auto newNode = this->create();
            if (newNode == nullptr) THROW_EXCEPTION(NoEnoughMemoryException, "No memory to create node ...");
            newNode->value = sourceNode->value;
            newNode->prev = targetNode;
            newNode->next = targetNode->next;

            targetNode->next = newNode;
            targetNode = newNode;
            sourceNode = sourceNode->next;
            this->m_size++;
            this->m_last = targetNode;
        }
    }

    CircularDoublyLinkedList(CircularDoublyLinkedList &&other) {
        this->m_size = other.m_size;
        this->m_header = other.m_header;
        this->m_last = other.m_last;

        other.m_size = 0;
        other.m_header.next = nullptr;
        other.m_last = reinterpret_cast<Node *>(&other.m_header);
    }

    void insert(size_t index, const T &value) override {
        index = index % (this->m_size + 1);
        if (index == this->m_size) return append(value);
        auto node = this->create();
        if (node == nullptr) THROW_EXCEPTION(NoEnoughMemoryException, "No momery to insert new element...");

        node->value = value;

        auto prev = position(index);
        auto next = prev->next;

        node->next = next;
        node->prev = prev;

        prev->next = node;
        next->prev = node;

        this->m_size++;
    }

    inline void append(const T &value) {
        auto node = this->create();
        if (node == nullptr) THROW_EXCEPTION(NoEnoughMemoryException, "No memory to create node ...");
        node->value = value;

        node->prev = this->m_last;
        node->next = this->m_last->next;

        this->m_last->next->prev = node;
        this->m_last->next = node;

        this->m_last = node;
        this->m_size++;
    }

    void removeAt(size_t index) override {
        index = mod(index);
        auto prev = position(index);
        auto toDel = prev->next;
        auto next = toDel->next;

        prev->next = next;
        next->prev = prev;

        this->destroy(toDel);

        this->m_size--;
    }

    T &last() override {
        if (this->m_size <= 0) THROW_EXCEPTION(InvalidOperationException, "There is no element in the container.");
        return this->m_header.prev->value;
    }

    void clear() override {
        while (this->m_size > 0) {
            removeAt(0);
        }
    }
    Iterator end() override { return Iterator(reinterpret_cast<Node *>(&this->m_header)); }

    Iterator end() const override { return Iterator(reinterpret_cast<Node *>(&this->m_header)); }

    ~CircularDoublyLinkedList() { clear(); }

    T &operator[](size_t index) override {
        index = mod(index);
        return position(index)->next->value;
    }

protected:
    size_t mod(size_t index) const { return (this->m_size == 0) ? 0 : (index % this->m_size); }
    Node *position(size_t index) const override {
        auto node = reinterpret_cast<Node *>(&(this->m_header));
        for (size_t i = 0; i < index; i++) {
            node = node->next;
        }
        return node;
    }
};
} // namespace Kylin
#endif // DUALCIRCULARLIST_H