#include "snake.h"
#include <stdlib.h>

struct snake* add_snake(struct snake* snake,int x,int y){
    struct snake* head = calloc(1,sizeof(struct snake));
    head->x = x;
    head->y = y;
    head->next = snake;
    return head;
}

struct snake* remove_snake(struct snake* snake) {
    if (snake == NULL) {
        return NULL;
    }

    if (snake->next == NULL) {
        free(snake);
        return NULL;
    }

    struct snake* current = snake;
    while (current->next->next != NULL) {
        current = current->next;
    }

    free(current->next);
    current->next = NULL;

    return snake;
}

void free_snake(struct snake* sn) {
    struct snake* current = sn;
    struct snake* next;

    while (current!= NULL) {
        next = current->next;
        free(current);
        current = next;
    }
}

int is_snake(struct snake* snake,int x,int y){
    while (snake != NULL) {
        if (snake->x == x && snake->y == y) {
            return 1;
        }
        snake = snake->next;
    }
    return 0;
}

int step_state(struct state* st){
	int nx = (st->snake->x + st->sx);
    int ny = (st->snake->y + st->sy);
    return END_CONTINUE;
}