class Node:

    def __init__(self, data = None, next = None, prev = None):
        self.data = data
        self.next = next
        self.prev = prev

class DLL:

    def __init__(self):
        self.head = Node()
        self.tail = Node()
        self.head.next = self.tail
        self.tail.prev = self.head
        self.curr = self.tail
        self.size = 0
        self.pos = 0
        #self.reversed = False

    def insert(self, value):

        new_node = Node(value)
        #if self.reversed:
        #    new_node.next = self.curr.next
        #    new_node.prev = self.curr
        #    self.curr.next.prev = new_node
        #    self.curr.next = new_node
        #    self.curr = new_node
        #    self.size += 1
        #if self.pos == self.size and self.size != 0:
        #    new_node.next = self.tail
        #    new_node.prev = self.tail.prev
        #    self.curr.next = self.tail
        #    self.tail.prev = new_node
        #    self.curr = new_node


        if self.curr == self.head:

            print('You SNEAKI MADAFAKKA')
        else:
            new_node.next = self.curr
            new_node.prev = self.curr.prev
            self.curr.prev.next = new_node
            self.curr.prev = new_node
            self.curr = new_node
            self.size += 1



    def remove(self):
        if self.curr.data == None:
            return
        if self.curr != self.head and self.curr != self.tail:
            self.curr.next.prev = self.curr.prev
            self.curr.prev.next = self.curr.next
            self.size -= 1
            #if self.reversed:
            #    self.curr = self.curr.prev

            self.curr = self.curr.next



    def get_value(self):

        return self.curr.data

    def move_to_next(self):

        #if self.reversed:
        #    if self.curr.prev != None:
        #        self.curr = self.curr.prev
        #        self.pos -= 1


        if self.curr.next != None:
            if self.pos >= self.size:
                self.pos = self.size

            else:
                self.curr = self.curr.next
                self.pos += 1

        else:

            return
            #print('EKKKI Next REVERSE POS: ', self.pos)

    def move_to_prev(self):

        #if self.reversed:
        #    if self.curr == self.tail:
        #        self.curr = self.curr.next
        #    if self.curr.next != self.tail:
        #        self.curr = self.curr.next
        #        self.pos += 1
        #        print('POS' ,self.pos)
        #
        #    else:
        #        return


        if self.curr == self.head:
            self.curr = self.curr.prev

        if self.curr.prev != self.head:
            self.curr = self.curr.prev
            self.pos -= 1



        else:

            return

    def move_to_pos(self, position):

        if position > self.size or position < 0:
            return

        if self.pos == position:
            return

        if position == self.size:
            self.curr = self.tail
            #if self.reversed:
            #    self.pos = 0

            self.pos = self.size


        else:
            if position > self.pos:  #  move next
                while self.pos != position:
                    self.move_to_next()
                #self.move_to_pos(position)

            elif position < self.pos:  #  move prev
                while self.pos != position:
                    self.move_to_prev()
                    #print('PREv')
                    #print(position,':  BIL  :',self.pos)
                #self.move_to_pos(position)

            else:
                return

    def remove_all(self, value):

        #if self.reversed:
        #    iterator = self.tail.prev
#
        #    if self.curr.data == value:
        #        self.curr = self.tail.prev


        iterator = self.head.next
        if self.curr.data == value:
            self.curr = self.head.next

        while iterator != None:

            if iterator.data == value:
                iterator.prev.next = iterator.next
                iterator.next.prev = iterator.prev
                self.size -= 1

            #if self.reversed:
            #    iterator = iterator.prev

            iterator = iterator.next

        #if self.reversed:
#
        #    if self.curr.data == value:
        #        self.curr = self.tail.prev

        if self.curr.data == value:
            self.curr = self.head.next

    def reverse(self):

        temp_pointer = None
        self.curr = self.head

        while self.curr != None:
            temp_pointer = self.curr.prev
            self.curr.prev = self.curr.next
            self.curr.next = temp_pointer
            self.curr = self.curr.prev
        if temp_pointer != None:
            self.head = temp_pointer.prev
            self.curr = self.head.next

    def sort(self):

        if self.head.next == self.tail:
            return

        else:
            self.curr = self.head.next

            while self.curr.next != None:
                compare = self.curr.next
                while compare.next != None:
                    if self.curr.data > compare.data:
                        temp = self.curr.data
                        self.curr.data = compare.data
                        compare.data = temp

                    compare = compare.next
                self.curr = self.curr.next

            #self.reversed = False
            self.curr = self.head.next
            #if self.reversed:
            #    self.pos = self.size

            self.pos = 0

    def __len__(self):

        return self.size

    def __str__(self):

        ret_str = ''

        #if self.reversed:
        #    ret_val = self.tail.prev
        #    while ret_val.prev != None:
        #        ret_str += str(ret_val.data) + ' '
        #        ret_val = ret_val.prev


        ret_val = self.head.next
        while ret_val.next != None:
            ret_str += str(ret_val.data) + ' '
            ret_val = ret_val.next

        return ret_str

    #def getStatus(self):
    #    return self.reversed

    def getPos(self):
        return self.pos