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


static struct {
	unsigned char cp_low;
	char latin;
} gothic[] = {
	{0x30, 'a'},
	{0x31, 'b'},
	{0x32, 'g'},
	{0x32, 'G'},
	{0x33, 'd'},
	{0x33, 'D'},
	{0x34, 'e'},
	{0x35, 'q'},
	{0x36, 'z'},
	{0x37, 'h'},
	{0x38, 'T'},
	{0x39, 'i'},
	{0x3A, 'k'},
	{0x3B, 'l'},
	{0x3C, 'm'},
	{0x3D, 'n'},
	{0x3E, 'j'},
	{0x3F, 'u'},
	{0x40, 'p'},
	{0x42, 'r'},
	{0x43, 's'},
	{0x44, 't'},
	{0x45, 'w'},
	{0x45, 'y'},
	{0x46, 'f'},
	{0x47, 'x'},
	{0x48, 'v'},
	{0x48, 'W'},
	{0x49, 'o'}
};


enum libcharconv_result
libcharconv_gothic(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 && *s <= '9') {
			if (*n)
				goto no_conv;
			c = UINT32_C(0x10330) + (uint_least32_t)(*s - '1');
			*n = 1u;
			if (slen == 0u)
				goto convn_if_end;
			if (s[1] != '0')
				goto convn;
			c += 9u;
			*n += 1u;
			if (slen == 1u)
				goto convn_if_end;
			if (s[2] == '0') {
				c += 9u;
				*n += 1u;
			}
			goto convn;
		} else {
			for (i = 0u; i < sizeof(gothic) / sizeof(*gothic); i++)
				if (*s == gothic[i].latin)
					goto conv;
			*n += 1u;
		}
	}
no_conv:
	return LIBCHARCONV_NO_CONVERT;

conv:
	if (*n)
		goto no_conv;
	*n += 1u;
	c = (uint_least32_t)(UINT32_C(0x10300) | gothic[i].cp_low);
convn:
	if (*ncp)
		*cp = c;
	*ncp = 1u;
	return LIBCHARCONV_CONVERTED;
convn_if_end:
	if (*ncp)
		*cp = c;
	*ncp = 1u;
	return LIBCHARCONV_CONVERT_IF_END;
}