implement Sign;

include "sys.m";
	sys: Sys;
	sprint: import sys;
include "draw.m";
include "keyring.m";
	keyring: Keyring;
	DigestState, PK: import keyring;

Sign: module {
	init:	fn(nil: ref Draw->Context, args: list of string);
};

Metafilesizemax: con 8*1024;

hash := "sha1";

# usage: sign_test [hashname] < secretkey

init(nil: ref Draw->Context, argv: list of string)
{
	sys = load Sys Sys->PATH;
	keyring = load Keyring Keyring->PATH;

	if(len argv > 1)
		hash = hd tl argv;

	(skd, err) := readstdin(Metafilesizemax);
	if(err != nil) {

	} else {
		sk := keyring->strtosk(string skd);
		if(sk == nil) {
			warn("malformed secret key");
		} else {
			bytes := array of byte "some data";
			dstate := keyring->sha1(bytes, len bytes, nil, nil);
			if(dstate == nil) {
				warn("failed to make digest");
			} else {
				exp := 1258801674;  # long time in the future
				cert := keyring->sign(sk, exp, dstate, hash);
				if(cert == nil)
					warn("did not make certificate");
				else
					sys->print("%s", keyring->certtostr(cert));
			}
		}
	}
}

readstdin(maxsize: int): (array of byte, string)
{

	n := sys->readn(sys->fildes(0), d := array[maxsize] of byte, len d);
	if(n < 0)
		return (nil, sprint("read stdin %r"));
	if(n == len d)
		return (nil, sprint("file stdin too large"));
	return (d[:n], nil);
}

warn(s: string)
{
	sys->fprint(sys->fildes(2), "%s\n", s);
}