#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define STRING_MAX_LENGTH (50)

typedef struct _osoba* Position;

typedef struct _osoba
{
char ime[STRING_MAX_LENGTH];
char prezime[STRING_MAX_LENGTH];
int godinaRodenja;
Position next;
}Student;

typedef struct _studentPodaci
{
char ime[STRING_MAX_LENGTH];
char prezime[STRING_MAX_LENGTH];
int godinaRodenja;
}StudentPodaci;

int InsertAfter(Position head, StudentPodaci studentPodaci);
int InsertEnd(Position position, StudentPodaci studentPodaci);
void IspisListe(Position head);
int DeleteElement(Position position);
Position FindPreviousElement(Position head, char *prezime);

int IspisIzbornika();
void PrintElement(Position position);
StudentPodaci GetStudentDataFromConsole();
void FreeAlocatedData(Position head);

int main(int agrc, char *argv[])
{
    char izbor = 0;
    char prezime[STRING_MAX_LENGTH];
    Student head;
    StudentPodaci bufferStudent;
    Position bufferPosition;

    head.next = NULL;

    while (izbor != 'K' && izbor != 'k')
    {
        IspisIzbornika();
        scanf(" %c", &izbor);
        switch (izbor)
        {
            case '1':
                bufferStudent = GetStudentDataFromConsole();
                InsertAfter(&head, bufferStudent);
                break;
            case '2':
                IspisListe(&head);
                break;
            case '3':
                bufferStudent = GetStudentDataFromConsole();
                InsertEnd(&head, bufferStudent);
                break;
            case '4':
                printf("\nUnesi prezime studenta cije podatke ispisujemo: ");
                scanf("%s", prezime);
                bufferPosition = FindPreviousElement(&head, prezime);
                if (bufferPosition != NULL)
                    PrintElement(bufferPosition->next);
                else
                    printf("\nElement ne postoji u listi.");
                break;
            case '5':
                break;
            case 'k':
            case 'K':
                break;
            default:
                printf("\r\nPogresan izbor <%c>.\r\nPokusajte ponovno.\r\n", izbor);
            break;
        }
    }

    //FreeAlocatedData(&head);
    IspisListe(&head);
}

int IspisIzbornika()
{
printf("\r\n\r\n");
printf("\t1. Unos elementa u listu\r\n");
printf("\t2. Ispis liste\r\n");
printf("\t3. Unos na kraj\r\n");
printf("\t4. Pronadji po prezimenu\r\n");
printf("\t5. Izbrisi po prezimenu\r\n");
printf("\tK. Izlaz iz programa\r\n");
printf("\r\n\tIzbor : ");

return 0;
}

int InsertAfter(Position position, StudentPodaci studentPodaci)
{
    Position newItem = NULL;
    if (position == NULL)
    return -1;

    newItem = (Position)malloc(sizeof(Student));

    if (newItem == NULL)
    return -2;

    //inicijalizacija alocirane strukture
    newItem->next = NULL;
    newItem->godinaRodenja = studentPodaci.godinaRodenja;
    strcpy(newItem->ime, studentPodaci.ime);
    strcpy(newItem->prezime, studentPodaci.prezime);
    //unos u listu
    newItem->next = position->next;
    position->next = newItem;

    return 0;
}

int InsertEnd(Position position, StudentPodaci studentPodaci)
{
    while(position->next != NULL)
    position = position->next;

    InsertAfter(position, studentPodaci);

    return 0;
}

void IspisListe(Position head)
{
    while(head->next != NULL)
    {
        printf("%s %s %d", head->next->ime, head->next->prezime, head->next->godinaRodenja);
        printf("\n");
        head = head->next;
    }
}

int DeleteElement(Position position)
{
    Position temp = NULL;
    if((position->next != NULL || position->next->next != NULL) && position->next->next->ime != NULL)
    {
        temp = position->next;
        free(position->next);
        position = temp;
        return 1;
    }
    else
        return -1;
}

Position FindPreviousElement(Position head, char *prezime)
{
    Position temp = NULL;
    if ((head->next != NULL || head->next->next != NULL) && head->next->next->prezime != NULL);
    temp = head->next;

    return temp;
}

void PrintElement(Position position)
{
    if(position->next != NULL)
    printf("%s %s %d /n", position->ime, position->prezime, position->godinaRodenja);
}

StudentPodaci GetStudentDataFromConsole()
{
    StudentPodaci tempStudent;

    printf("Unesi ime: ");
    scanf(" %s", tempStudent.ime);
    printf("Unesi prezime: ");
    scanf(" %s", tempStudent.prezime);
    printf("Unesi godinu rodenja: ");
    scanf(" %d", &tempStudent.godinaRodenja);

    return tempStudent;
}

void FreeAlocatedData(Position head)
{
    free(head);
}