/*
 * DoubleLinkedList.c
 *
 *  Created on: Jun 26, 2014
 *      Author: Arun
 */


/*
 * DoubleLinkedList.c
 *
 *  Created on: Jun 18, 2014
 *      Author: Arun
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include "DoubleLinkedList.h"


typedef struct DNode mainTemp;
typedef struct DoubleLinkedList mainList;

//1 DONE
DoubleLinkedList* allocDList(uint elementSize){

    struct DoubleLinkedList* list = &mainList;

     list->head = NULL;
     list->tail = NULL;

     list->length = 0;
     list->elementSize = elementSize;

     return list;



}
//2 DONE
void releaseDList(DoubleLinkedList* list){

    struct DNode* node = list->head;
    struct DNode* next = NULL;

    while(node){

        struct DNode* next = node->next;
        free(node);
        node = next;

    }

}
//3 DONE
void insertDListElementAt(DoubleLinkedList* list, Object newElement, uint position){

    struct DNode* newNode = calloc(list, sizeOf(newElement));
    newNode->data = newElement;

    int counter = 0;

    struct _DNode* current = list->head;

    while(counter < list->length){

            if(counter == position){

                current->next = newNode;
                newNode->prev = current;
                newNode->next = current->next;
                current->next->prev = newNode;

            }
            counter++;
            current = current->next;
        }

}
//4 DONE
void appendDList(DoubleLinkedList* list, Object newElement){

    struct DNode* newNode = calloc(list, sizeOf(newElement));
    newNode->data = newElement;

    newNode = list->tail->next; // setting newNode as current tail's next
    newNode->prev = list->tail; // setting up current tail as newNodes's prev
    newNode = list->tail; // newNode as the new tail


}
//5 DONE
void insertDList(DoubleLinkedList* list, Object newElement){



    struct DNode* newNode = (DNode*)calloc(list, sizeOf(newElement));

    newNode->data = newElement;


    newNode->next = list->head;
    newNode = list->head->prev;
    newNode->prev = NULL;
    list->head = newNode;

}
//6 DONE
DoubleLinkedList* reverseDList(DoubleLinkedList* list){

    struct DoubleLinkedList* newList = NULL;
    newList = (struct DoubleLinkedList*) malloc(sizeOf(DoubleLinkedList));

    struct DNode* temp = NULL;

    temp = (DNode*)malloc(sizeOf(DNode));

    temp = list->tail;



    while(temp->prev != NULL){

        appendDList(newList, temp->data);
        temp = temp->prev;

    }

    return newList;




}
//7 DONE
DoubleLinkedList* halfList(DoubleLinkedList* list){

    struct DNode* slow = list->head;
    struct DNode* fast = list->head;
    struct DoubleLinkedList* newList = malloc(uint);

    if(list->head != NULL){

        while(fast != NULL && fast->next != NULL){

            fast = fast->next->next;
            slow = slow->next;

        } // slow now ='s midpoint

        while(slow != NULL){

            appendDList(newList, slow->data);
            slow = slow->next;

        }

        return newList;
    }

    return newList;

}
//8 DONE
Object removeDList(DoubleLinkedList* list, int position){

    int counter = 0;
    struct _DNode* temp = list->head;

    while(counter < list->length){

        if(counter == position){

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

            return temp->data;

        }
        counter++;
        temp = temp->next;
    }

return NULL;

}

//9 DONE
void printDList(DoubleLinkedList* list){

    struct _DNode* temp = list->head;

    while(temp->next != NULL){

        printf("%d", temp->data);
        temp = temp->next;

    }

}

void debugDList(DoubleLinkedList* list){
    DNode* iter = list->head;
    while(iter){
        printf("%p\t", iter);
        iter = iter->next;
    }
    printf("\n");
    iter = list->tail;
    while(iter){
        printf("%p\t", iter);
        iter = iter->prev;
    }
    printf("\n\n");
}
// end of DoubleLinkedList.c


// DoubleLinkedList.h

/*
 * DoubleLinkedList.h
 *
 *  Created on: Jun 18, 2014
 *      Author: Arun
 */

#ifndef DOUBLELINKEDLIST_H_
#define DOUBLELINKEDLIST_H_

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>


typedef unsigned int uint;
typedef unsigned long ulong;
typedef void* Object;

typedef struct _DNode{

    Object data;

    struct _DNode* prev;

    struct _DNode* next;

} DNode;


typedef struct _DoubleLinkedList{

    DNode* head;

    DNode* tail;

    uint length;

    uint elementSize;

} DoubleLinkedList;

//1 DONE
DoubleLinkedList* allocDList(uint elementSize);
//2 DONE
void releaseDList(DoubleLinkedList* list);
//3 DONE
void insertDListElementAt(DoubleLinkedList* list, Object newElement, uint position);
//4 DONE
void appendDList(DoubleLinkedList* list, Object newElement);
//5 DONE
void insertDList(DoubleLinkedList* list, Object newElement);
//6 DONE
DoubleLinkedList* reverseDList(DoubleLinkedList* list);
//7 DONE
DoubleLinkedList* halfList(DoubleLinkedList* list);
//8 DONE
Object removeDList(DoubleLinkedList* list, int position);
//9 DONE
void printDList(DoubleLinkedList* list);
void debugDList(DoubleLinkedList* list);


#endif /* DOUBLELINKEDLIST_H_ */