#include <u.h>
#include <libc.h>
#include <plumb.h>

/* Works with the following plumb rule for Ocaml errors:
type is text
data matches 'File "([.a-zA-Z¡-￿0-9_/+\-]*[a-zA-Z¡-￿0-9_/+\-])", line ([0-9]+), characters ([0-9]+)-([0-9]+).*'
arg isfile	$1
data set	$file
attr add	line=$2
attr add	schar=$3
attr add	echar=$4
plumb to	mladdr
*/

enum MSG {
	LINE,
	SCHAR,
	ECHAR,
	NMSG,
};
char *msgs[] = {
	[LINE] "line",
	[SCHAR] "schar",
	[ECHAR] "echar",
};

int
unpack(char **attrs, Plumbmsg *msg)
{
	Plumbattr *attr;
	int i;

	attr = msg->attr;
	for(i = 0; i < NMSG; i++){
		if(attr == nil){
			syslog(0, "mladdr", "Bad msg: Not enough attributes");
			return -1;
		}
		if(strcmp(attr->name, msgs[i]) != 0){
			syslog(0, "mladdr", "Bad msg: looking for %s but got %s", msgs[i], attr->name);
			return -1;
		}
		attrs[i] = attr->value;
		attr = attr->next;
	}
	return 0;
}

void
doplumb(int infd, int outfd)
{
	static char addrbuf[1024];
	static Plumbattr outattr = {
		.name "addr",
		.value addrbuf,
	};
	static Plumbmsg outmsg = {
		.src "mladdr",
		.dst "edit",
		.type "text",
		.attr &outattr,
	};
	Plumbmsg *msg;
	char *attrs[3];
	long line;

	for(;;){
		msg = plumbrecv(infd);
		if(msg == nil){
			syslog(0, "mladdr", "Bad message: %r\n");
			return;
		}
		if(unpack(attrs, msg) < 0)
			continue;
		line = strtol(attrs[LINE], nil, 0) - 1;
		outmsg.data = msg->data;
		outmsg.ndata = msg->ndata;
		seprint(addrbuf, addrbuf+sizeof(addrbuf), "%ld+#%s,%ld+#%s" , line, attrs[SCHAR], line, attrs[ECHAR]);
		plumbsend(outfd, &outmsg);
		plumbfree(msg);
	}
}

int
eplumbopen(char *port, int mode)
{
	int fd;

	fd = plumbopen(port, mode);
	if(fd < 0){
		fprint(2, "Could not open plumb port: %r\n");
		exits("clogged");
	}
	return fd;
}

void
main(void)
{
	int infd, outfd;

	close(0);
	close(1);
	infd = eplumbopen("mladdr", OREAD);
	outfd = eplumbopen("send", OWRITE);
	switch(rfork(RFPROC|RFFDG|RFNOWAIT|RFNOTEG)){
	case -1:
		fprint(2, "Could not fork child: %r\n");
		exits("rfork");
	case 0:
		close(2);
		doplumb(infd, outfd);
		break;
	}
	exits(nil);
}