#include <u.h>
#include <libc.h>
#include <bio.h>
#include <thread.h>
#include "dat.h"

void	mainctl(void*);
void	startcmd(char *[], int*, int*, int*);
void	stdout2body(void*);

int	stdin, stdout, notepg;

int dirty = 0;

Window *win;
int		hostpt;

void
usage(void)
{
	threadprint(2, "usage: win [command]\n");
	threadexitsall("usage");
}

void
threadmain(int argc, char *argv[])
{
	int i, j;
	char *dir, *tag, *name;
	char buf[1024], **av;

	ARGBEGIN{
	}ARGEND

	if(argc == 0){
		av = emalloc(3*sizeof(char*));
		av[0] = "rc";
		av[1] = "-i";
		name = getenv("sysname");
	}else{
		av = argv;
		name = utfrrune(av[0], '/');
		if(name)
			name++;
		else
			name = av[0];
	}

	if(getwd(buf, sizeof buf) == 0)
		dir = "/";
	else
		dir = buf;
	dir = estrdup(dir);
	tag = estrdup(dir);
	tag = eappend(estrdup(tag), "/-", name);
	win = newwindow();
	winname(win, tag);
	wintagwrite(win, "Send Noscroll", 5+8);
	threadcreate(mainctl, win, STACK);
	startpipe();

	startcmd(av, &stdin, &stdout, &notepg);

	proccreate(stdout2body, nil, STACK);

	strcpy(buf, "win");
	j = 3;
	for(i=0; i<argc && j+1+strlen(argv[i])+1<sizeof buf; i++){
		strcpy(buf+j, " ");
		strcpy(buf+j+1, argv[i]);
		j += 1+strlen(argv[i]);
	}

	ctlprint(win->ctl, "scroll");
	winsetdump(win, dir, buf);
}

int
EQUAL(char *s, char *t)
{
	while(tolower(*s) == tolower(*t++))
		if(*s++ == '\0')
			return 1;
	return 0;
}

int
command(Window *w, char *s)
{
	while(*s==' ' || *s=='\t' || *s=='\n')
		s++;
	if(strcmp(s, "Delete")==0){
		windel(w, 1);
		threadexitsall(nil);
		return 1;
	}
	if(strcmp(s, "Del")==0){
		if(windel(w, 0))
			threadexitsall(nil);
		return 1;
	}
	if(EQUAL(s, "scroll")){
		ctlprint(w->ctl, "scroll\nshow");
		return 1;
	}
	if(EQUAL(s, "noscroll")){
		ctlprint(w->ctl, "noscroll");
		return 1;
	}
	return 0;
}

int
sendinput(Window *w, ulong q0, ulong q1)
{
	char *buf, *s, *t;
	int nsent, m, n;

	buf = emalloc((q1-q0)*UTFmax+1);
	n = winread(w, q0, q1, buf);
	s = buf;
	while(n > 0){
		t = strpbrk(s, "\n\004");
		if(t == nil)
			break;
		m = (t+1)-s;
		if(*t == '\n')
			write(stdin, s, m);
		else
			write(stdin, s, m-1);
		n -= m;
		s += m;
	}
	/* calculate number of runes sent */
	*s = '\0';
	nsent = utflen(buf);
	free(buf);
	return nsent;
}

void
sendit(char *s)
{
	int n;
	char tmp[32];

	n = strlen(s);
	write(win->body, s, n);
	if(s[n-1]!='\n'  && s[n-1]!='\004')
		write(win->body, "\n", 1);
	winselect(win, "$", 1);
	seek(win->addr, 0UL, 0);
	if(read(win->addr, tmp, 2*12) == 2*12)
		hostpt += sendinput(win, hostpt, atol(tmp));
}

void
execevent(Window *w, Event *e, int (*command)(Window*, char*))
{
	Event *ea, *e2;
	int na;
	char *s, *t;

	ea = nil;
	e2 = nil;
	if(e->flag & 2)
		e2 = recvp(w->cevent);
	if(e->flag & 8){
		ea = recvp(w->cevent);
		na = ea->nb;
		recvp(w->cevent);
	}else
		na = 0;
	s = e->b;
	/* if it's a known command, do it */
	if((e->flag&2) && e->nb==0)
		s = e2->b;
	if(na){
		t = emalloc(strlen(s)+1+na+1);
		sprint(t, "%s %s", s, ea->b);
		s = t;
	}
	/* if it's a long message, it can't be for us anyway */
	if(!command(w, s) && s[0]!='\0'){	/* send it as typed text */
		/* if it's a built-in from the tag, send it back */
		if(e->flag & 1)
			threadprint(w->event, "%c%c%d %d\n", e->c1, e->c2, e->q0, e->q1);
		else	/* send text to main window */
			sendit(s);
	}
	if(na)
		free(s);
}

void
mainctl(void *v)
{
	Window *w;
	Event *e;
	int delta;
	char tmp[32];

	w = v;
	proccreate(wineventproc, w, STACK);

	hostpt = 0;
	winsetaddr(w, "0", 0);
	for(;;){
		e = recvp(w->cevent);
		switch(e->c1){
		default:
		Unknown:
			threadprint(2, "unknown message %c%c\n", e->c1, e->c2);
			break;

		case 'S':	/* output to stdout */
			write(w->data, e->b, e->nb);
			threadprint(w->ctl, "dot=addr\n");
			hostpt += e->nr;
			break;
	
		case 'E':	/* write to body; can't affect us */
			break;
	
		case 'F':	/* generated by our actions; ignore */
			break;
	
		case 'K':
			switch(e->c2){
			case 'D':
				if(e->q1 < hostpt)
					hostpt -= (e->q1-e->q0);
				else if(e->q0 < hostpt)
					hostpt = e->q0;
				break;
			case 'I':
				if(e->nr>0 && e->r[e->nr-1]==0x7F){
					/* do full reset of state, just in case we've lost track */
					write(notepg, "interrupt", 9);
					winselect(w, "$", 1);
					ctlprint(w->ctl, "dot=addr");
					tmp[0] = 0;
					seek(w->addr, 0, 0);
					read(w->addr, tmp, 24);
					hostpt = atoi(tmp);
					break;
				}
				delta = e->q1-e->q0;
				if(e->q1 < hostpt)
					hostpt += delta;
				else if(e->q0>=hostpt && e->nr>0 && (e->r[e->nr-1]=='\n' || e->r[e->nr-1]=='\004'))
					hostpt += sendinput(w, hostpt, e->q1);
				break;
			}
			break;
	
		case 'M':
			switch(e->c2){
			case 'x':
			case 'X':
				execevent(w, e, command);
				break;
	
			case 'l':	/* reflect all searches back to acme */
			case 'L':
				if(e->flag & 2)
					recvp(w->cevent);
				winwriteevent(w, e);
				break;
	
			case 'I':
				if(e->q1 < hostpt)
					hostpt += e->q1-e->q0;
				else
					hostpt += sendinput(w, hostpt, e->q1);
				break;

			case 'D':
				if(e->q1 < hostpt)
					hostpt -= (e->q1-e->q0);
				else if(e->q0 < hostpt)
					hostpt = e->q0;
				break;
			case 'd':	/* modify away; we don't care */
			case 'i':
				break;
	
			default:
				goto Unknown;
			}
		}
	}
}

/* turn writes to stdout (seen as reads by us) into pseudo-events.  e->nr is set but not e->r */
void
stdout2body(void*)
{
	int i, j, w, n, partial, nb;
	Event *e[4], *ep;
	Rune r;
	char *t, tmp[UTFmax];

	for(i=0; i<nelem(e); i++){
		e[i] = emalloc(sizeof(Event));
		e[i]->c1 = 'S';
	}
	
	n = 0;
	partial = 0;
	for(;;){
		ep = e[n];
		n = (n+1) % nelem(e);
		nb = partial+read(stdout, ep->b+partial, EVENTSIZE-partial-1);	/* -1 to leave terminal \0 */
		if(nb <= 0)
			break;
		if(strlen(ep->b) < nb){	/* nulls in data */
			t = emalloc(nb+1);
			for(i=j=0; i<nb; i++)
				if(ep->b[i] != '\0')
					t[j++] = ep->b[i];
			memmove(ep->b, t, j);
			nb = j;
			free(t);
		}
		/* process bytes into runes, transferring terminal partial runes into next buffer */
		for(i=j=0; i<nb && fullrune(ep->b+i, nb-i); i+=w,j++)
			w = chartorune(&r, ep->b+i);
		memmove(tmp, ep->b+i, nb-i);
		ep->nb = i;
		ep->nr = j;
		ep->b[i] = '\0';
		ep->r[j] = L'\0';
		sendp(win->cevent, ep);
		partial = nb-i;
		memmove(e[n]->b, tmp, partial);
	}
	threadexitsall(nil);
}

enum
{
	NARGS		= 100,
	NARGCHAR	= 8*1024,
	EXECSTACK 	= STACK+(NARGS+1)*sizeof(char*)+NARGCHAR
};

struct Exec
{
	char		**argv;
	Channel	*cpid;
};

int
lookinbin(char *s)
{
	if(s[0] == '/')
		return 0;
	if(s[0]=='.' && s[1]=='/')
		return 0;
	if(s[0]=='.' && s[1]=='.' && s[2]=='/')
		return 0;
	return 1;
}

/* adapted from mail.  not entirely free of details from that environment */
void
execproc(void *v)
{
	struct Exec *e;
	char *cmd, **av;
	Channel *cpid;

	e = v;
	rfork(RFFDG);
	av = e->argv;
	close(0);
	open("/dev/cons", OREAD);
	close(1);
	open("/dev/cons", OWRITE);
	dup(1, 2);
	cpid = e->cpid;
	free(e);
	procexec(cpid, av[0], av);
	if(lookinbin(av[0])){
		cmd = estrstrdup("/bin/", av[0]);
		procexec(cpid, cmd, av);
	}
	sendul(cpid, 0UL);
	threadexits("can't exec");
}

void
startcmd(char *argv[], int *stdin, int *stdout, int *notepg)
{
	struct Exec *e;
	Channel *cpid;
	char buf[64];
	int pid;

	e = emalloc(sizeof(struct Exec));
	if(bind("#|", "/dev/acme", MREPL) < 0)
		error("can't bind pipe: %r");
	bind("/dev/acme/data", "/dev/cons", MREPL);
	e->argv = argv;
	cpid = chancreate(sizeof(ulong), 0);
	e->cpid = cpid;
	proccreate(execproc, e, EXECSTACK);
	do
		pid = recvul(cpid);
	while(pid == -1);
	if(pid == 0){
		error("can't exec %s: %r", argv[0]);
		threadexitsall("can't exec");
	}
	sprint(buf, "/proc/%d/notepg", pid);
	*notepg = open(buf, OWRITE);
	*stdin = open("/dev/acme/data1", OWRITE);
	*stdout = open("/dev/acme/data1", OREAD);
	sprint(buf, "/mnt/wsys/%d", win->id);
	bind(buf, "/dev/acme", MREPL);
}