#include<iostream>
#include<stdio.h>
#include<stdlib.h>
using namespace std;


//Implementare coada dubla

struct Command {
    char* name;
};
struct QueueNode
{
    Command* info;
    QueueNode* next;
    QueueNode* prev;
};
QueueNode* createQueueNode(Command* is)
{
    //1. declare a new variable
    QueueNode* newEl = NULL;
    //2. allocate memory
    newEl = (QueueNode*)malloc(sizeof(QueueNode));
    //3. initialization
    newEl->info = is;
    newEl->next = newEl->prev = NULL;
    //4. return
    return newEl;
}
void putQueueElement(QueueNode*& head, QueueNode* node)
{
    if (head == NULL)
    {
        //one queue element (circular)
        head = node;
        head->next = head->prev = head;
    }
    else
    {
        node->next = head;
        node->prev = head->prev;
        head->prev->next = node;
        head->prev = node;
    }
}
void printfQueueElements(QueueNode* head)
{
    if (head)
    {
        QueueNode* tmp = head;
        while (tmp->next != head)
        {
            printf("Comanda: %s\n", tmp->info->name);
            tmp = tmp->next;
        }
        printf("Comanda: %s\n", tmp->info->name);
        printf("----------Backwards----------------\n");
        while (tmp != head)
        {
            printf("Comanda: %s\n", tmp->info->name);
            tmp = tmp->prev;
        }
        printf("Comanda: %s\n", tmp->info->name);
    }
}
bool emptyQueue(QueueNode* head)
{
    return (head == nullptr) ? true : false;
}
void printQueueElement(QueueNode* el)
{
    printf("Subscriber: %s\n", el->info->name);
    printf("\n");
}
QueueNode* getQueueElement(QueueNode*& head)
{
    QueueNode* aux = head;
    if (head == head->next && head == head->prev)
    {
        head = nullptr;
    }
    else
    {
        head->next->prev = head->prev;
        head->prev->next = head->next;
        head = head->next;
    }
    return aux;
}

//End Coada Dubla

void main()
{
    //Apel Coada Dubla
    FILE* pFile = fopen("Text.txt", "r");
    QueueNode* head = NULL;
    if (pFile)
    {
        char buffer[50];
        Command* subscriber = NULL;
        fscanf(pFile, "%[^\n]s", buffer);

        while (!feof(pFile))
        {
            subscriber = (Command*)malloc(sizeof(Command));
            subscriber->name = (char*)malloc(strlen(buffer) + 1);
            strcpy(subscriber->name, buffer);
            fscanf(pFile, "\n");
            QueueNode* newNode = createQueueNode(subscriber);
            putQueueElement(head, newNode);
            fscanf(pFile, "%[^\n]s", buffer);
        }
        fclose(pFile);
    }
    printf("----------Print circular double link list--------\n");
    printfQueueElements(head);
    printf("\n----------Print Queue elements----------\n");
    while (!emptyQueue(head))
    {
        QueueNode* element = getQueueElement(head);
        printQueueElement(element);
    }
    getchar();
    //End Apel Coada Dubla
}