#include "paint.h"

static int mainerr;
extern void (*_sysfatal)(char*, va_list);

/* write sysfatal messages to the main window, instead of to a log
window which is about to disappear
*/
void
_paintfatal(char *fmt, va_list args)
{
	char buf[1024];

	vseprint(buf, buf + sizeof(buf), fmt, args);

	if(argv0)
		fprint(mainerr, "%s: %s\n", argv0, buf);
	else
		fprint(mainerr, "%s\n", buf);

	threadexitsall(buf);
}

static void
copyproc(void *arg)
{
	int in;
	uchar buf[1024];
	int n;

	threadsetname("copy");

	in = *(int *)arg;
	while((n = read(in, buf, sizeof buf)) > 0) {
		if(write(1, buf, n) != n)
			sysfatal("log: copy write: %r");
	}
	if(n < 0)
		sysfatal("log: copy read: %r");
}

static void
stampproc(void *argvp)
{
	void **argv;
	int *inp, *outp;

	threadsetname("stamp");

	argv = argvp;
	inp = argv[0];
	outp = argv[1];

	close(inp[1]);
	close(outp[0]);
	if(dup(inp[0], 0) < 0 || dup(outp[1], 1) < 0)
		sysfatal("log: dup: %r");

	procexecl(nil, "/bin/stamp", "stamp", "iso", nil);
	procexecl(nil, "/bin/aux/clog", "aux/clog", "/fd/0", "/fd/1", nil);
	procexecl(nil, "/bin/cat", "cat", nil);
	sysfatal("log: exec: %r");
}

/* -> lp[1] -> lp[0] -> logproc -> sp[1] -> sp[0] -> stampproc ->
	cp[1] -> cp[0] -> copyproc -> /dev/cons
*/
static void
logproc(void *arg)
{
	int lp[2], sp[2], cp[2], cons, wctl, label;
	void *stampargv[2];
	int opened;
	uchar buf[1024];
	int n;

	threadsetname("log");

	lp[0] = ((int *)arg)[0];
	lp[1] = ((int *)arg)[1];

	close(lp[1]);
	if(pipe(sp) < 0 || pipe(cp) < 0)
		sysfatal("log: pipe 2: %r");

	stampargv[0] = sp;
	stampargv[1] = cp;
	procrfork(stampproc, stampargv, 1024, RFFDG|RFNAMEG|RFENVG);

	proccreate(copyproc, &cp[0], 4*1024);
	close(cp[1]);

	opened = 0;
	SET(cons);
	SET(wctl);
	while((n = read(lp[0], buf, sizeof buf)) >= 0) {
		/* if the window has never been opened or has been closed */
		if(opened == 0 || read(label, &label, 0) < 0) {
			if(opened) {
				close(cons);
				close(wctl);
				close(label);
			}
			opened = 1;

			if(newwindow("-hide -scroll") < 0)
				sysfatal("log: newwindow: %r");
			if((cons = open("/dev/cons", OWRITE)) < 0)
				sysfatal("log: open /dev/cons: %r");
			if((wctl = open("/dev/wctl", OWRITE)) < 0)
				sysfatal("log: open /dev/wctl: %r");
			if((label = open("/dev/label", ORDWR)) < 0)
				sysfatal("log: open /dev/label: %r");
			if(fprint(label, "%s errors", argv0) < 0)
				sysfatal("log: write label: %r");

			/* replace copyproc's stdout */
			if(dup(cons, 1) < 0)
				sysfatal("log: dup: %r");
		}

		fprint(wctl, "unhide");
		write(sp[1], buf, n);
	}
	sysfatal("log: read: %r");
}

void
logproccreate(void)
{
	int p[2];

	if((mainerr = dup(2, -1)) < 0)
		sysfatal("log: dup mainerr: %r");

	if(pipe(p) < 0)
		sysfatal("log: pipe 1: %r");

	procrfork(logproc, p, 8*1024, RFFDG|RFNAMEG|RFENVG);

	/* errors from logproc will continue writing to the main window */
	_sysfatal = _paintfatal;
	if(dup(p[1], 2) < 0)
		sysfatal("log: dup 2: %r");
	close(p[0]);
	close(p[1]);
}