class Node(object):
    def __init__(self, item, next):
        self.item = item
        self.next = next


class Link(object):
    def __init__(self, init_list: list):
        """
        初始化
        """
        self._link = None
        self._init_link(init_list)
        self._reverse_link = None

    def _init_link(self, init_list: list):
        init_list.reverse()
        for item in init_list:
            self._link = Node(item, self._link)

    @property
    def list(self):
        """
        将链表转换成list
        :return:
        """
        res = []
        link = self._link
        while link:
            res.append(link.item)
            link = link.next
        return res

    def clear(self):
        """
        清空链表
        :return:
        """
        self._link = None

    def delete(self, item):
        """
        删除某个元素
        :param item:
        :return:
        """
        link = self._link
        prev = None
        i = 0
        while link:
            if item == link.item:
                if prev is None:
                    self._link = link.next
                else:
                    prev.next = link.next
                break
            prev = link
            link = link.next

    def insert(self, item, index):
        """
        向链表index位置插入一个item元素
        :param item:
        :param index:
        :return:
        """
        i = 0
        if index == 0:
            self._link = Node(item, self._link)
        else:
            if index == self.length - 1:
                _index = index
            else:
                _index = index - 1
            link = self._link
            while link:
                if _index == i:
                    link.next = Node(item, link.next)
                    break
                i = i + 1
                link = link.next

    def append(self, item):
        """
        向链表末尾添加一个元素
        :param item:
        :return:
        """
        self.insert(item, self.length - 1)

    def reverse(self, next=None):
        """
        链表反转（递归）
        :return:
        """
        if next is None:
            link = self._link
        else:
            link = next
        self._reverse_link = Node(link.item, self._reverse_link)
        if link.next is None:
            self._link = self._reverse_link
            self._reverse_link = None
            return
        self.reverse(link.next)



    @property
    def length(self):
        """
        获取链表的长度
        :return:
        """
        return len(self.list)

    def empty(self):
        """
        链表是否为空
        :return:
        """
        if self._link is None:
            return True
        else:
            return False

    def in_link(self, item):
        """
        判断元素是否在链表中
        :param item:
        :return:
        """
        link = self._link
        while link:
            if item == link.item:
                return True
            link = link.next
        return False


if __name__ == '__main__':
    link = Link(['zhangbo', 'liudong', 'zhuxiang', 'suirun'])
    print(link.list)
    link.insert('wuxiaokang', 3)
    print(link.list)
    link.append('hufang')
    print(link.list)
    link.insert('shenming', 0)
    print(link.list)
    link.delete('suirun')
    print(link.list)
    link.reverse()
    print(link.list)