#include "h/mh.h"
#include "h/mime.h"
#include <stdio.h>

void fold(FILE *restrict stream, const char *restrict name, const char *restrict body)
{
	const char *restrict body_next;
	const char *restrict wsp;
	const char *restrict wsp_next;
	const bool crlf = strchr(body, '\r');
	size_t namelen = fprintf(stream, "%s:", name);

	if (namelen >= MAXTEXTPERLN) {
		if (crlf) {
			fputs("\r\n ", stream);
		} else {
			fputs("\n ", stream);
		}
		namelen = 0;
	}
	
	while (*body) {
		body_next = strchr(body, '\n');
		if ((unsigned long) (body_next - body) <= MAXTEXTPERLN - namelen) {
			fwrite(body, 1, body_next - body + 1, stream);
			namelen = 0;
			body = body_next + 1;
			continue;
		}
		wsp = strpbrk(body, " \t");

		/* if now whitespace is in the current line just print the curret line as is */
		if (!wsp || wsp > body_next) {
			fwrite(body, 1, body_next - body + 1, stream);
			namelen = 0;
			body = body_next + 1;
			continue;
		}

		while ((unsigned long)(wsp - body) <= MAXTEXTPERLN - namelen) {
			wsp_next = strpbrk(wsp, " \t");
			if (!wsp_next) {
				break;
			}
			if (wsp_next > body_next) {
				break;
			}
			wsp = wsp_next;
		}

		fwrite(body, 1, wsp - body, stream);
		if (crlf) {
			fputs("\r\n", stream);
		} else {
			fputs("\n", stream);
		}
		fputc(*wsp, stream);
		namelen = 1;
		body = wsp + 1;
	}
}