87 lines
2.0 KiB
C
87 lines
2.0 KiB
C
#include "snake.h"
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#include <stdlib.h>
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struct snake* add_snake(struct snake* snake, int x, int y) {
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struct snake* head = calloc(1, sizeof(struct snake));
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if (head == NULL) {
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return snake;
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}
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head->x = x;
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head->y = y;
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head->next = snake;
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return head;
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}
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struct snake* remove_snake(struct snake* snake) {
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if (snake == NULL) {
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return NULL;
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}
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if (snake->next == NULL) {
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free(snake);
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return NULL;
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}
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struct snake* prev = snake;
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struct snake* last = snake->next;
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while (last->next != NULL) {
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prev = last;
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last = last->next;
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}
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prev->next = NULL;
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free(last);
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return snake;
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}
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void free_snake(struct snake* sn) {
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while (sn != NULL) {
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struct snake* next = sn->next;
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free(sn);
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sn = next;
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}
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}
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int is_snake(struct snake* snake, int x, int y) {
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for (struct snake* node = snake; node != NULL; node = node->next) {
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if (node->x == x && node->y == y) {
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return 1;
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}
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}
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return 0;
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}
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int step_state(struct state* st) {
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if (st == NULL || st->snake == NULL) {
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return END_USER;
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}
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int nx = st->snake->x + st->sx;
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int ny = st->snake->y + st->sy;
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int food_index = -1;
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if (nx < 0 || ny < 0 || nx >= st->width || ny >= st->height) {
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return END_WALL;
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}
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if (is_snake(st->snake, nx, ny)) {
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return END_SNAKE;
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}
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for (int i = 0; i < FOOD_COUNT; i++) {
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if (st->foodx[i] == nx && st->foody[i] == ny) {
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food_index = i;
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break;
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}
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}
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st->snake = add_snake(st->snake, nx, ny);
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if (food_index >= 0) {
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st->foodx[food_index] = -1;
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st->foody[food_index] = -1;
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for (int i = 0; i < FOOD_COUNT; i++) {
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if (st->foodx[i] >= 0 && st->foody[i] >= 0) {
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return END_CONTINUE;
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}
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}
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return END_FOOD;
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}
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st->snake = remove_snake(st->snake);
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return END_CONTINUE;
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}
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