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

struct snake* add_snake(struct snake* snake, int x, int y) {
    struct snake* new_head = (struct snake*)malloc(sizeof(struct snake));
    if (new_head == NULL) {
        fprintf(stderr, "Memory allocation failed.\n");
        exit(EXIT_FAILURE);
    }
    new_head->x = x;
    new_head->y = y;
    new_head->next = snake;
    return new_head;
}

struct snake* remove_snake(struct snake* snake) {
    if (snake == NULL) {
        return NULL;
    }
    struct snake* new_head = snake->next;
    free(snake);
    return new_head;
}
void test_remove_snake_non_empty() {
    
    struct snake* tail = calloc(1, sizeof(struct snake));
    tail->x = 3;
    tail->y = 3;
    struct snake* head = calloc(1, sizeof(struct snake));
    head->x = 2;
    head->y = 2;
    head->next = tail;

    
    struct snake* new_head = remove_snake(head);

    
    if (new_head != NULL && new_head->x == 3 && new_head->y == 3) {
        printf("Test passed: new head coordinates are correct.\n");
    } else {
        printf("Test failed: new head coordinates are incorrect.\n");
    }

   
    free(new_head);
    free(tail);
}

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;
}

void free_snake(struct snake* sn) {
    struct snake* current = sn;
    while (current != NULL) {
        struct snake* temp = current;
        current = current->next;
        free(temp);
    }
}

int step_state(struct state* state) {
    
    return END_CONTINUE;
}