STATIC uint8_t readmove(char);
STATIC uint8_t readmodifier(char);
STATIC int64_t writemoves(uint8_t *, int, uint64_t, char *);

STATIC uint8_t
readmove(char c)
{
	switch (c) {
	case 'U':
		return MOVE_U;
	case 'D':
		return MOVE_D;
	case 'R':
		return MOVE_R;
	case 'L':
		return MOVE_L;
	case 'F':
		return MOVE_F;
	case 'B':
		return MOVE_B;
	default:
		return UINT8_ERROR;
	}
}

STATIC uint8_t
readmodifier(char c)
{
	switch (c) {
	case '1': /* Fallthrough */
	case '2': /* Fallthrough */
	case '3':
		return c - '0' - 1;
	case '\'':
		return 2;
	default:
		return 0;
	}
}

STATIC int64_t
writemoves(uint8_t *m, int n, uint64_t buf_size, char *buf)
{
	int i;
	uint64_t len;
	const char *s;
	char *b;

	if (buf_size == 0) {
		LOG("Error: cannot write moves to buffer of size 0.\n");
		return NISSY_ERROR_BUFFER_SIZE;
	}

	for (i = 0, b = buf; i < n; i++, b++, buf_size--) {
		s = movestr[m[i]];
		len = strlen(s);
		if (len >= buf_size) {
			LOG("Error: the given buffer is too small for "
			     "writing the given moves.\n");
			goto writemoves_error;
		}
		memcpy(b, s, len);
		buf_size -= len;
		b += len;	
		*b = ' ';
	}

	if (b != buf)
		b--; /* Remove last space */
	*b = '\0';

	return buf_size;

writemoves_error:
	*buf = '\0';
	return NISSY_ERROR_BUFFER_SIZE;
}