#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#define MAX_NAZIV 30
#define MAX 15
#define MIN 1

typedef struct student*Position;
typedef struct student
{
	int brojIndexa;
	char *ime;
	char *prezime;
	int orderNum;
	Position next;
}Student;

Position KreirajClan();
int CitanjeIzFilea(Position);
int RandomBroj();
int FreeData(Position);
int IspisListe(Position);
int SortiranjeUnosa(Position, int, char*, char*, int);
int BrisanjeIstih(Position);
int IzbrisiClanove(Position , int );
int SortirajClanove(Position);

int main()
{

	Student root;
	root.next = NULL;
	srand((unsigned)time(NULL));
	printf("\t------Lista studenata------\n\n");
	CitanjeIzFilea(&root);
	IspisListe(&root);
	printf("\n\n\t------Lista studenata s jedistvenim orderNumb------\n\n");
	BrisanjeIstih(&root);
	IspisListe(&root);
	printf("\n\n\t------Lista studenata s jedistvenim orderNumb (sortirana)------\n\n");
	SortirajClanove(&root);
	IspisListe(&root);
	printf("\n\n\t------Brisanje liste------\n\n");
	FreeData(&root);
	IspisListe(&root);

	return 0;
}

int CitanjeIzFilea(Position p)
{
	FILE*fp;
	Position newItem;
	int broj=0;
	int rndBr = 0;
	char *ime=(char*)malloc(sizeof(char)*MAX_NAZIV);
	char *prezime = (char*)malloc(sizeof(char)*MAX_NAZIV);

	fp = fopen("studenti.txt", "r");
	if (fp == NULL)
	{
		printf("Datoteka se nije uspjesno otvorila");
		return -1;
	}
	while (!feof(fp))
	{
		ime = (char*)malloc(MAX_NAZIV * sizeof(char));
		prezime = (char*)malloc(MAX_NAZIV * sizeof(char));


		fscanf(fp, "%d %s %s",&broj, ime,prezime);
		rndBr = RandomBroj();
		if (p->next == NULL)
		{
			Position newItem;
			newItem = KreirajClan();
			newItem->brojIndexa = broj;
			newItem->ime = ime;
			newItem->prezime = prezime;
			newItem->orderNum = rndBr;
			newItem->next = p->next;
			p->next = newItem;
		}
		else
		{

			SortiranjeUnosa(p, broj, ime, prezime, rndBr);
		}

	}
	fclose(fp);
	return 0;
}
int SortiranjeUnosa(Position p, int index, char*ime, char*prezime, int rnd)
{
	p = p->next;
	Position newItem;
	newItem = KreirajClan();
	newItem->brojIndexa = index;
	newItem->ime = ime;
	newItem->prezime = prezime;
	newItem->orderNum = rnd;
	newItem->next = NULL;


	while (p->next!=NULL)
	{
		if (strcmp(newItem->prezime, p->next->prezime) < 0)
		{
			newItem->next = p->next;
			p->next = newItem;
			return 0;
		}
		else
		{
			p = p->next;

		}

	}
	if (newItem->next == NULL)
	{
		p->next = newItem->next;
		p->next = newItem;
	}

	return 0;
}

Position KreirajClan()
{
	Position temp;

	temp = (Position)malloc(sizeof(Student));
	temp->brojIndexa = 0;
	temp->orderNum = NULL;

	return temp;
}

int RandomBroj()
{
	int broj;

	broj = rand() % (MAX - MIN + 1) + MIN;

	return broj;
}
int BrisanjeIstih(Position p)
{
	Position i=NULL;
	int broj;
	int brojac;

		for (broj=1; broj < 16; broj++)
		{
			i = p;
			brojac = 0;
			while (i!=NULL)
			{
				if (i->orderNum == broj)
				{
					brojac++;
				}

			i= i->next;
			}
			if (brojac > 1)
			{
				IzbrisiClanove(p, broj);
			}

		}
	return 0;
}
int IzbrisiClanove(Position p, int br)
{
	Position previ = NULL;
	Position i = NULL;
	Position temp=NULL;


	while (p->next!=NULL)
	{

		if (br == p->next->orderNum)
		{
			temp = p->next;
			p->next = temp->next;
			free(temp);

		}
		else
		{
			p = p->next;
		}
	}
	return 0;
}
int SortirajClanove(Position p)
{
	Position i = NULL;
	Position j = NULL;
	Position prevj = NULL;
	Position temp = NULL;
	Position end=NULL;

	i = p;

	while (i->next!=end)
	{
		prevj = i;
		j = i->next;
		while (j->next!=end)
		{
			if (j->orderNum > j->next->orderNum)
			{
				temp = j->next;
				prevj->next = temp;
				j->next = temp->next;
				temp->next = j;
				j = temp;
			}
			prevj = j;
			j=j->next;
		}
		end = j;
	}
	return 0;
}
int IspisListe(Position p)
{
	if (p->next == NULL)
	{
		printf("\t   Lista je prazna!!\n\n");
		return -1;
	}
	p = p->next;
	printf("\n INDEKS\tIME\t\tPREZIME\t\tORDERnumb\n\n\n");
	while (p != NULL)
	{

		printf("  %d\t%s\t\t%s\t\t%d\n", p->brojIndexa, p->ime, p->prezime, p->orderNum);
		p = p->next;
	}
	return 0;
}
int FreeData(Position p)
{

	Position temp = NULL;
	while (p->next!=NULL)
	{
		temp = p->next;
		p->next = temp->next;
		free(temp);
	}
	return 0;
}