#include <stdio.h>
#include <stdlib.h>
#include "lists.h"

int main()
{
	struct S_LIST l = slist_init();
	
	char *s = "Hello";
	slist_add(&l, s);
	slist_add(&l, "Good");
	slist_add(&l, "bye");
	
	slist_print(&l);
	printf("count: %d \n", l.count);
	
	slist_delete(&l, 1);
	
	slist_print(&l);
	printf("count: %d \n", l.count);
	
	slist_foreach(&l, print_it);
	
	slist_delete_all(&l);
	slist_print(&l);
	
	return 0;
}

#ifndef S_LIST_H_INCLUDED
#  define S_LIST_H_INCLUDED

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

struct S_LIST
{
	int count;
	struct S_LIST_E *head;
	struct S_LIST_E *tail;
};

struct S_LIST_E
{
	void *data;
	struct S_LIST_E *next;
	struct S_LIST_E *prev;
};


struct S_LIST slist_init()
{
	struct S_LIST l = {0,NULL,NULL};
	return l;
}

void slist_add(struct S_LIST *sl, void *data)
{
	struct S_LIST_E *e;
	if((e = (struct S_LIST_E*) malloc(sizeof(struct S_LIST_E))) != NULL)
	{
		if(sl->head==NULL)
		{
		
			sl->head = e;
			sl->tail = sl->head;
			sl->tail->next = NULL;
			sl->tail->prev = NULL;
		}
		else
		{
			sl->tail->next = e;
			sl->tail->next->prev = sl->tail;
			sl->tail = sl->tail->next;
			sl->tail->next = NULL;
		}
		sl->tail->data = data;
		sl->count++;
	}
}

void slist_delete(struct S_LIST *sl, int pos)
{
	struct S_LIST_E *e = sl->head;
	int c = 0;
	while(e!=NULL)
	{
		if(c == pos)
		{
			struct S_LIST_E *tmp = e;
			e->prev->next = tmp->next;
			e->next->prev = tmp->prev;
			free(e);
			//free(tmp);
			sl->count--;
			return;
		}
		e = e->next;
		c++;
	}
}

void slist_delete_all(struct S_LIST *sl)
{
	struct S_LIST_E *e = sl->head;
	struct S_LIST_E *v = NULL;
	while(e != NULL)
	{
		v = e;
		e = e->next;
		free(v);
	}
	sl->head = NULL;
	sl->tail = NULL;
	sl->count = 0;
}

void slist_print(struct S_LIST *sl)
{
	struct S_LIST_E *e = sl->head;
	while(e!=NULL)
	{
		printf("%s \n", (char*)e->data);
		e = e->next;
	}
}

void print_it(void *s)
{
	printf("%s \n", (char*)s);
}

void slist_foreach(struct S_LIST *sl, void (*func)(void *data))
{
	struct S_LIST_E *e = sl->head;
	while(e!=NULL)
	{
		func(e->data);
		e = e->next;
	}
}
#endif