/* See LICENSE file for copyright and license details. */
#include "lib-common.h"


enum libcharconv_result
libcharconv_yijing_hexagrams(const char *s, size_t slen, size_t *n, uint_least32_t *cp, size_t *ncp)
{
	uint_least32_t c;
	size_t i;
	*n = 0;
	for (; slen--; s++) {
		if ('1' <= s[0] && s[0] <= '2') {
			if (slen == 0u)
				return LIBCHARCONV_INDETERMINATE;
			if ('1' > s[1] || s[1] > '2')
				goto no_match;
			if (slen == 1u)
				return LIBCHARCONV_INDETERMINATE;
			if ('1' > s[2] || s[2] > '2')
				goto no_match;
			if (slen == 2u)
				return LIBCHARCONV_INDETERMINATE;
			if ('1' > s[3] || s[3] > '2')
				goto no_match;
			if (slen == 3u)
				return LIBCHARCONV_INDETERMINATE;
			if ('1' > s[4] || s[4] > '2')
				goto no_match;
			if (slen == 4u)
				return LIBCHARCONV_INDETERMINATE;
			if ('1' > s[5] || s[5] > '2')
				goto no_match;
			i =  s[5] == '2' ?  1u : 0u;
			i |= s[4] == '2' ?  2u : 0u;
			i |= s[3] == '2' ?  4u : 0u;
			i |= s[2] == '2' ?  8u : 0u;
			i |= s[1] == '2' ? 16u : 0u;
			i |= s[0] == '2' ? 32u : 0u;
			c = UINT32_C(0x4D00) | libcharconv_yijing_hexagrams_[i];
			goto conv;
		} else {
		no_match:
			*n += 1u;
		}
	}
no_conv:
	return LIBCHARCONV_NO_CONVERT;

conv:
	if (*n)
		goto no_conv;
	if (*ncp)
		*cp = c;
	*n += 6u;
	*ncp = 1u;
	return LIBCHARCONV_CONVERTED;
}