/* $Id: docbook2mdoc.c,v 1.74 2019/03/26 18:32:07 schwarze Exp $ */
/*
 * Copyright (c) 2014 Kristaps Dzonsons <kristaps@bsd.lv>
 * Copyright (c) 2019 Ingo Schwarze <schwarze@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
#include <assert.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>

#include "node.h"
#include "format.h"

/*
 * The implementation of the mdoc(7) formatter.
 */

enum	linestate {
	LINE_NEW = 0,
	LINE_TEXT,
	LINE_MACRO
};

struct	format {
	int		 level;      /* Header level, starting at 1. */
	enum linestate	 linestate;
};

static void	 pnode_print(struct format *, struct pnode *);


static void
macro_open(struct format *p, const char *name)
{
	switch (p->linestate) {
	case LINE_TEXT:
		putchar('\n');
		/* FALLTHROUGH */
	case LINE_NEW:
		putchar('.');
		p->linestate = LINE_MACRO;
		break;
	case LINE_MACRO:
		putchar(' ');
		break;
	}
	fputs(name, stdout);
}

static void
macro_close(struct format *p)
{
	assert(p->linestate == LINE_MACRO);
	putchar('\n');
	p->linestate = LINE_NEW;
}

static void
macro_line(struct format *p, const char *name)
{
	macro_open(p, name);
	macro_close(p);
}

#define	ARG_SPACE	1  /* Insert whitespace before this argument. */
#define	ARG_SINGLE	2  /* Quote argument if it contains whitespace. */
#define	ARG_QUOTED	4  /* We are already in a quoted argument. */
#define	ARG_UPPER	8  /* Covert argument to upper case. */
/*
 * Print an argument string on a macro line, collapsing whitespace.
 */
static void
macro_addarg(struct format *p, const char *arg, int flags)
{
	const char	*cp;

	assert(p->linestate == LINE_MACRO);

	/* Quote if requested and necessary. */

	if ((flags & (ARG_SINGLE | ARG_QUOTED)) == ARG_SINGLE) {
		for (cp = arg; *cp != '\0'; cp++)
			if (isspace((unsigned char)*cp))
				break;
		if (*cp != '\0') {
			if (flags & ARG_SPACE) {
				putchar(' ');
				flags &= ~ ARG_SPACE;
			}
			putchar('"');
			flags = ARG_QUOTED;
		}
	}

	for (cp = arg; *cp != '\0'; cp++) {

		/* Collapse whitespace. */

		if (isspace((unsigned char)*cp)) {
			flags |= ARG_SPACE;
			continue;
		} else if (flags & ARG_SPACE) {
			putchar(' ');
			flags &= ~ ARG_SPACE;
		}

		/* Escape us if we look like a macro. */

		if ((flags & ARG_QUOTED) == 0 &&
		    (cp == arg || isspace((unsigned char)cp[-1])) &&
		    isupper((unsigned char)cp[0]) &&
		    islower((unsigned char)cp[1]) &&
		    (cp[2] == '\0' || cp[2] == ' ' ||
		     (islower((unsigned char)cp[2]) &&
		      (cp[3] == '\0' || cp[3] == ' '))))
			fputs("\\&", stdout);

		if (*cp == '"')
			fputs("\\(dq", stdout);
		else if (flags & ARG_UPPER)
			putchar(toupper((unsigned char)*cp));
		else
			putchar(*cp);
		if (*cp == '\\')
			putchar('e');
	}
}

static void
macro_argline(struct format *p, const char *name, const char *arg)
{
	macro_open(p, name);
	macro_addarg(p, arg, ARG_SPACE);
	macro_close(p);
}

/*
 * Recursively append text from the children of a node to a macro line.
 */
static void
macro_addnode(struct format *p, struct pnode *pn, int flags)
{
	int		 quote_now;

	assert(p->linestate == LINE_MACRO);

	/*
	 * If the only child is a text node, just add that text,
	 * letting macro_addarg() decide about quoting.
	 */

	pn = TAILQ_FIRST(&pn->childq);
	if (pn != NULL && pn->node == NODE_TEXT &&
	    TAILQ_NEXT(pn, child) == NULL) {
		macro_addarg(p, pn->b, flags);
		return;
	}

	/*
	 * If we want the argument quoted and are not already
	 * in a quoted context, quote now.
	 */

	quote_now = 0;
	if (flags & ARG_SINGLE) {
		if ((flags & ARG_QUOTED) == 0) {
			if (flags & ARG_SPACE) {
				putchar(' ');
				flags &= ~ARG_SPACE;
			}
			putchar('"');
			flags |= ARG_QUOTED;
			quote_now = 1;
		}
		flags &= ~ARG_SINGLE;
	}

	/*
	 * Iterate to child and sibling nodes,
	 * inserting whitespace between nodes.
	 */

	while (pn != NULL) {
		if (pn->node == NODE_TEXT)
			macro_addarg(p, pn->b, flags);
		else
			macro_addnode(p, pn, flags);
		pn = TAILQ_NEXT(pn, child);
		flags |= ARG_SPACE;
	}
	if (quote_now)
		putchar('"');
}

static void
macro_nodeline(struct format *p, const char *name, struct pnode *pn, int flags)
{
	macro_open(p, name);
	macro_addnode(p, pn, ARG_SPACE | flags);
	macro_close(p);
}

/*
 * If the next node is a text node starting with closing punctuation,
 * emit the closing punctuation as a trailing macro argument.
 */
static void
macro_closepunct(struct format *p, struct pnode *pn)
{
	if ((pn = TAILQ_NEXT(pn, child)) != NULL &&
	    pn->node == NODE_TEXT && pn->bsz > 0 &&
	    (pn->b[0] == ',' || pn->b[0] == '.') &&
	    (pn->bsz == 1 || isspace((unsigned char)pn->b[1]))) {
		putchar(' ');
		putchar(pn->b[0]);
		pn->b++;
		pn->bsz--;
	}
	macro_close(p);
}

static void
print_text(struct format *p, const char *word)
{
	switch (p->linestate) {
	case LINE_NEW:
		break;
	case LINE_TEXT:
		putchar(' ');
		break;
	case LINE_MACRO:
		macro_close(p);
		break;
	}
	fputs(word, stdout);
	p->linestate = LINE_TEXT;
}

static void
pnode_printpara(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	if ((pp = TAILQ_PREV(pn, pnodeq, child)) == NULL &&
	    (pp = pn->parent) == NULL)
		return;

	switch (pp->node) {
	case NODE_ENTRY:
	case NODE_LISTITEM:
		return;
	case NODE_PREFACE:
	case NODE_SECTION:
		if (p->level < 3)
			return;
		break;
	default:
		break;
	}
	macro_line(p, "Pp");
}

/*
 * If the SYNOPSIS macro has a superfluous title, kill it.
 */
static void
pnode_printrefsynopsisdiv(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *pq;

	TAILQ_FOREACH_SAFE(pp, &pn->childq, child, pq)
		if (pp->node == NODE_TITLE)
			pnode_unlink(pp);

	macro_line(p, "Sh SYNOPSIS");
}

/*
 * Start a hopefully-named `Sh' section.
 */
static void
pnode_printrefsect(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;
	const char	*title;
	int		 flags, level;

	if (pn->parent == NULL)
		return;

	level = ++p->level;
	flags = ARG_SPACE;
	if (level == 1)
		flags |= ARG_UPPER;
	if (level < 3) {
		switch (pn->node) {
		case NODE_CAUTION:
		case NODE_NOTE:
		case NODE_TIP:
		case NODE_WARNING:
			level = 3;
			break;
		default:
			break;
		}
	}

	TAILQ_FOREACH(pp, &pn->childq, child)
		if (pp->node == NODE_TITLE)
			break;

	if (pp == NULL) {
		switch (pn->node) {
		case NODE_PREFACE:
			title = "Preface";
			break;
		case NODE_CAUTION:
			title = "Caution";
			break;
		case NODE_NOTE:
			title = "Note";
			break;
		case NODE_TIP:
			title = "Tip";
			break;
		case NODE_WARNING:
			title = "Warning";
			break;
		default:
			title = "Unknown";
			break;
		}
	}

	switch (level) {
	case 1:
		macro_open(p, "Sh");
		break;
	case 2:
		macro_open(p, "Ss");
		break;
	default:
		pnode_printpara(p, pn);
		macro_open(p, "Sy");
		break;
	}

	if (pp != NULL) {
		macro_addnode(p, pp, flags);
		pnode_unlink(pp);
	} else
		macro_addarg(p, title, ARG_SPACE | ARG_QUOTED);
	macro_close(p);
}

/*
 * Start a reference, extracting the title and volume.
 */
static void
pnode_printciterefentry(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *title, *manvol;

	title = manvol = NULL;
	TAILQ_FOREACH(pp, &pn->childq, child) {
		if (pp->node == NODE_MANVOLNUM)
			manvol = pp;
		else if (pp->node == NODE_REFENTRYTITLE)
			title = pp;
	}
	macro_open(p, "Xr");
	if (title == NULL)
		macro_addarg(p, "unknown", ARG_SPACE);
	else
		macro_addnode(p, title, ARG_SPACE | ARG_SINGLE);
	if (manvol == NULL)
		macro_addarg(p, "1", ARG_SPACE);
	else
		macro_addnode(p, manvol, ARG_SPACE | ARG_SINGLE);
	macro_close(p);
	pnode_unlinksub(pn);
}

static void
pnode_printrefmeta(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *title, *manvol;

	title = manvol = NULL;
	TAILQ_FOREACH(pp, &pn->childq, child) {
		if (pp->node == NODE_MANVOLNUM)
			manvol = pp;
		else if (pp->node == NODE_REFENTRYTITLE)
			title = pp;
	}
	macro_open(p, "Dt");
	if (title == NULL)
		macro_addarg(p, "UNKNOWN", ARG_SPACE);
	else
		macro_addnode(p, title, ARG_SPACE | ARG_SINGLE | ARG_UPPER);
	if (manvol == NULL)
		macro_addarg(p, "1", ARG_SPACE);
	else
		macro_addnode(p, manvol, ARG_SPACE | ARG_SINGLE);
	macro_close(p);
	pnode_unlink(pn);
}

static void
pnode_printfuncdef(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *ftype, *func;

	ftype = func = NULL;
	TAILQ_FOREACH(pp, &pn->childq, child) {
		if (pp->node == NODE_TEXT)
			ftype = pp;
		else if (pp->node == NODE_FUNCTION)
			func = pp;
	}
	if (ftype != NULL)
		macro_argline(p, "Ft", ftype->b);
	macro_open(p, "Fo");
	if (func == NULL)
		macro_addarg(p, "UNKNOWN", ARG_SPACE);
	else
		macro_addnode(p, func, ARG_SPACE | ARG_SINGLE);
	macro_close(p);
}

/*
 * The <mml:mfenced> node is a little peculiar.
 * First, it can have arbitrary open and closing tokens, which default
 * to parentheses.
 * Second, >1 arguments are separated by commas.
 */
static void
pnode_printmathfenced(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	printf("left %s ", pnode_getattr_raw(pn, ATTRKEY_OPEN, "("));

	pp = TAILQ_FIRST(&pn->childq);
	pnode_print(p, pp);

	while ((pp = TAILQ_NEXT(pp, child)) != NULL) {
		putchar(',');
		pnode_print(p, pp);
	}
	printf("right %s ", pnode_getattr_raw(pn, ATTRKEY_CLOSE, ")"));
	pnode_unlinksub(pn);
}

/*
 * These math nodes require special handling because they have infix
 * syntax, instead of the usual prefix or prefix.
 * So we need to break up the first and second child node with a
 * particular eqn(7) word.
 */
static void
pnode_printmath(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	pp = TAILQ_FIRST(&pn->childq);
	pnode_print(p, pp);

	switch (pn->node) {
	case NODE_MML_MSUP:
		fputs(" sup ", stdout);
		break;
	case NODE_MML_MFRAC:
		fputs(" over ", stdout);
		break;
	case NODE_MML_MSUB:
		fputs(" sub ", stdout);
		break;
	default:
		break;
	}

	pp = TAILQ_NEXT(pp, child);
	pnode_print(p, pp);
	pnode_unlinksub(pn);
}

static void
pnode_printfuncprototype(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *fdef;

	TAILQ_FOREACH(fdef, &pn->childq, child)
		if (fdef->node == NODE_FUNCDEF)
			break;

	if (fdef != NULL)
		pnode_printfuncdef(p, fdef);
	else
		macro_line(p, "Fo UNKNOWN");

	TAILQ_FOREACH(pp, &pn->childq, child)
		if (pp->node == NODE_PARAMDEF)
			macro_nodeline(p, "Fa", pp, ARG_SINGLE);

	macro_line(p, "Fc");
	pnode_unlinksub(pn);
}

/*
 * The <arg> element is more complicated than it should be because text
 * nodes are treated like ".Ar foo", but non-text nodes need to be
 * re-sent into the printer (i.e., without the preceding ".Ar").
 * This also handles the case of "repetition" (or in other words, the
 * ellipsis following an argument) and optionality.
 */
static void
pnode_printarg(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;
	struct pattr	*ap;
	int		 isop, isrep;

	isop = 1;
	isrep = 0;
	TAILQ_FOREACH(ap, &pn->attrq, child) {
		if (ap->key == ATTRKEY_CHOICE &&
		    (ap->val == ATTRVAL_PLAIN || ap->val == ATTRVAL_REQ))
			isop = 0;
		else if (ap->key == ATTRKEY_REP && ap->val == ATTRVAL_REPEAT)
			isrep = 1;
	}
	if (isop)
		macro_open(p, "Op");

	TAILQ_FOREACH(pp, &pn->childq, child) {
		if (pp->node == NODE_TEXT)
			macro_open(p, "Ar");
		pnode_print(p, pp);
		if (isrep && pp->node == NODE_TEXT)
			macro_addarg(p, "...", ARG_SPACE);
	}
	pnode_unlinksub(pn);
}

static void
pnode_printgroup(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *np;
	struct pattr	*ap;
	int		 isop, sv;

	isop = 1;
	TAILQ_FOREACH(ap, &pn->attrq, child)
		if (ap->key == ATTRKEY_CHOICE &&
		    (ap->val == ATTRVAL_PLAIN || ap->val == ATTRVAL_REQ)) {
			isop = 0;
			break;
		}

	/*
	 * Make sure we're on a macro line.
	 * This will prevent pnode_print() for putting us on a
	 * subsequent line.
	 */
	sv = p->linestate == LINE_NEW;
	if (isop)
		macro_open(p, "Op");
	else if (sv)
		macro_open(p, "No");

	/*
	 * Keep on printing text separated by the vertical bar as long
	 * as we're within the same origin node as the group.
	 * This is kind of a nightmare.
	 * Eh, DocBook...
	 * FIXME: if there's a "Fl", we don't cut off the leading "-"
	 * like we do in pnode_print().
	 */
	TAILQ_FOREACH(pp, &pn->childq, child) {
		pnode_print(p, pp);
		np = TAILQ_NEXT(pp, child);
		while (np != NULL) {
			if (pp->node != np->node)
				break;
			macro_addarg(p, "|", ARG_SPACE);
			macro_addnode(p, np, ARG_SPACE);
			pp = np;
			np = TAILQ_NEXT(np, child);
		}
	}
	if (sv)
		macro_close(p);
	pnode_unlinksub(pn);
}

static void
pnode_printprologue(struct format *p, struct ptree *tree)
{
	struct pnode	*refmeta;

	refmeta = tree->root == NULL ? NULL :
	    pnode_findfirst(tree->root, NODE_REFMETA);

	macro_line(p, "Dd $Mdocdate" "$");
	if (refmeta == NULL) {
		macro_open(p, "Dt");
		macro_addarg(p,
		    pnode_getattr_raw(tree->root, ATTRKEY_ID, "UNKNOWN"),
		    ARG_SPACE | ARG_SINGLE | ARG_UPPER);
		macro_addarg(p, "1", ARG_SPACE);
		macro_close(p);
	} else
		pnode_printrefmeta(p, refmeta);
	macro_line(p, "Os");

	if (tree->flags & TREE_EQN) {
		macro_line(p, "EQ");
		print_text(p, "delim $$");
		macro_line(p, "EN");
	}
}

/*
 * We can have multiple <term> elements within a <varlistentry>, which
 * we should comma-separate as list headers.
 */
static void
pnode_printvarlistentry(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;
	int		 first = 1;

	macro_open(p, "It");
	TAILQ_FOREACH(pp, &pn->childq, child) {
		if (pp->node != NODE_TERM)
			continue;
		if ( ! first)
			macro_addarg(p, ",", 0);
		pnode_print(p, pp);
		first = 0;
	}
	macro_close(p);
	TAILQ_FOREACH(pp, &pn->childq, child)
		if (pp->node != NODE_TERM)
			pnode_print(p, pp);
	pnode_unlinksub(pn);
}

static void
pnode_printtitle(struct format *p, struct pnode *pn)
{
	struct pnode	*pp, *pq;

	TAILQ_FOREACH_SAFE(pp, &pn->childq, child, pq) {
		if (pp->node == NODE_TITLE) {
			pnode_printpara(p, pp);
			pnode_print(p, pp);
			pnode_unlink(pp);
		}
	}
}

static void
pnode_printrow(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	macro_line(p, "Bl -dash -compact");
	TAILQ_FOREACH(pp, &pn->childq, child) {
		macro_line(p, "It");
		pnode_print(p, pp);
	}
	macro_line(p, "El");
	pnode_unlink(pn);
}

static void
pnode_printtable(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	pnode_printtitle(p, pn);
	macro_line(p, "Bl -ohang");
	while ((pp = pnode_findfirst(pn, NODE_ROW)) != NULL) {
		macro_line(p, "It Table Row");
		pnode_printrow(p, pp);
	}
	macro_line(p, "El");
	pnode_unlinksub(pn);
}

static void
pnode_printlist(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	pnode_printtitle(p, pn);
	macro_argline(p, "Bl",
	    pn->node == NODE_ORDEREDLIST ? "-enum" : "-bullet");
	TAILQ_FOREACH(pp, &pn->childq, child) {
		macro_line(p, "It");
		pnode_print(p, pp);
	}
	macro_line(p, "El");
	pnode_unlinksub(pn);
}

static void
pnode_printvariablelist(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;

	pnode_printtitle(p, pn);
	macro_line(p, "Bl -tag -width Ds");
	TAILQ_FOREACH(pp, &pn->childq, child) {
		if (pp->node == NODE_VARLISTENTRY)
			pnode_print(p, pp);
		else
			macro_nodeline(p, "It", pp, 0);
	}
	macro_line(p, "El");
	pnode_unlinksub(pn);
}

/*
 * Print a parsed node (or ignore it--whatever).
 * This is a recursive function.
 * FIXME: if we're in a literal context (<screen> or <programlisting> or
 * whatever), don't print inline macros.
 */
static void
pnode_print(struct format *p, struct pnode *pn)
{
	struct pnode	*pp;
	const char	*ccp;
	char		*cp;
	int		 last;
	enum linestate	 sv;

	if (pn == NULL)
		return;

	sv = p->linestate;

	switch (pn->node) {
	case NODE_APPLICATION:
		macro_open(p, "Nm");
		break;
	case NODE_ANCHOR:
		/* Don't print anything! */
		return;
	case NODE_ARG:
		pnode_printarg(p, pn);
		break;
	case NODE_AUTHOR:
		macro_open(p, "An");
		break;
	case NODE_AUTHORGROUP:
		macro_line(p, "An -split");
		break;
	case NODE_BOOKINFO:
		macro_line(p, "Sh NAME");
		break;
	case NODE_CITEREFENTRY:
		pnode_printciterefentry(p, pn);
		break;
	case NODE_CITETITLE:
		macro_open(p, "%T");
		break;
	case NODE_CODE:
		macro_open(p, "Li");
		break;
	case NODE_COMMAND:
		macro_open(p, "Nm");
		break;
	case NODE_CONSTANT:
		macro_open(p, "Dv");
		break;
	case NODE_EDITOR:
		print_text(p, "editor:");
		macro_open(p, "An");
		break;
	case NODE_EMAIL:
		macro_open(p, "Aq Mt");
		break;
	case NODE_EMPHASIS:
	case NODE_FIRSTTERM:
		macro_open(p, "Em");
		break;
	case NODE_ENVAR:
		macro_open(p, "Ev");
		break;
	case NODE_FILENAME:
		macro_open(p, "Pa");
		break;
	case NODE_FUNCTION:
		macro_open(p, "Fn");
		break;
	case NODE_FUNCPROTOTYPE:
		pnode_printfuncprototype(p, pn);
		break;
	case NODE_FUNCSYNOPSISINFO:
		macro_open(p, "Fd");
		break;
	case NODE_INDEXTERM:
		return;
	case NODE_INFORMALEQUATION:
		macro_line(p, "EQ");
		break;
	case NODE_INLINEEQUATION:
		if (p->linestate == LINE_NEW)
			p->linestate = LINE_TEXT;
		putchar('$');
		break;
	case NODE_ITEMIZEDLIST:
		pnode_printlist(p, pn);
		break;
	case NODE_GROUP:
		pnode_printgroup(p, pn);
		break;
	case NODE_KEYSYM:
		macro_open(p, "Sy");
		break;
	case NODE_LEGALNOTICE:
		macro_line(p, "Sh LEGAL NOTICE");
		break;
	case NODE_LINK:
		ccp = pnode_getattr_raw(pn, ATTRKEY_LINKEND, NULL);
		if (ccp == NULL)
			break;
		macro_argline(p, "Sx", ccp);
		return;
	case NODE_LITERAL:
		macro_open(p, "Li");
		break;
	case NODE_LITERALLAYOUT:
		macro_argline(p, "Bd", pnode_getattr(pn, ATTRKEY_CLASS) ==
		    ATTRVAL_MONOSPACED ? "-literal" : "-unfilled");
		break;
	case NODE_MML_MFENCED:
		pnode_printmathfenced(p, pn);
		break;
	case NODE_MML_MROW:
	case NODE_MML_MI:
	case NODE_MML_MN:
	case NODE_MML_MO:
		if (TAILQ_EMPTY(&pn->childq))
			break;
		fputs(" { ", stdout);
		break;
	case NODE_MML_MFRAC:
	case NODE_MML_MSUB:
	case NODE_MML_MSUP:
		pnode_printmath(p, pn);
		break;
	case NODE_OPTION:
		macro_open(p, "Fl");
		break;
	case NODE_ORDEREDLIST:
		pnode_printlist(p, pn);
		break;
	case NODE_PARA:
		pnode_printpara(p, pn);
		break;
	case NODE_PARAMETER:
		macro_nodeline(p, "Fa", pn, ARG_SINGLE);
		pnode_unlinksub(pn);
		break;
	case NODE_QUOTE:
		macro_open(p, "Qo");
		break;
	case NODE_PROGRAMLISTING:
	case NODE_SCREEN:
		macro_line(p, "Bd -literal");
		break;
	case NODE_REFENTRYINFO:
		/* Suppress. */
		pnode_unlinksub(pn);
		break;
	case NODE_REFMETA:
		abort();
		break;
	case NODE_REFNAME:
		/* Suppress non-text children... */
		macro_open(p, "Nm");
		macro_addnode(p, pn, ARG_SPACE | ARG_SINGLE);
		pnode_unlinksub(pn);
		break;
	case NODE_REFNAMEDIV:
		macro_line(p, "Sh NAME");
		break;
	case NODE_REFPURPOSE:
		macro_open(p, "Nd");
		break;
	case NODE_REFSYNOPSISDIV:
		pnode_printrefsynopsisdiv(p, pn);
		break;
	case NODE_PREFACE:
	case NODE_SECTION:
	case NODE_NOTE:
	case NODE_TIP:
	case NODE_CAUTION:
	case NODE_WARNING:
		pnode_printrefsect(p, pn);
		break;
	case NODE_REPLACEABLE:
		macro_open(p, "Ar");
		break;
	case NODE_SBR:
		macro_line(p, "br");
		break;
	case NODE_SGMLTAG:
		macro_open(p, "Li");
		break;
	case NODE_STRUCTNAME:
		macro_open(p, "Vt");
		break;
	case NODE_TABLE:
	case NODE_INFORMALTABLE:
		pnode_printtable(p, pn);
		break;
	case NODE_TEXT:
		if (pn->bsz == 0) {
			assert(pn->real != pn->b);
			break;
		}
		if (p->linestate == LINE_NEW)
			p->linestate = LINE_TEXT;
		else
			putchar(' ');

		/*
		 * Output all characters, squeezing out whitespace
		 * between newlines.
		 * XXX: all whitespace, including tabs (?).
		 * Remember to escape control characters and escapes.
		 */
		cp = pn->b;

		/*
		 * There's often a superfluous "-" in its <option> tags
		 * before the actual flags themselves.
		 * "Fl" does this for us, so remove it.
		 */
		if (pn->parent != NULL &&
		    pn->parent->node == NODE_OPTION &&
		    *cp == '-')
			cp++;
		for (last = '\n'; *cp != '\0'; ) {
			if (last == '\n') {
				/* Consume all whitespace. */
				if (isspace((unsigned char)*cp)) {
					while (isspace((unsigned char)*cp))
						cp++;
					continue;
				} else if (*cp == '\'' || *cp == '.')
					fputs("\\&", stdout);
			}
			putchar(last = *cp++);
			/* If we're a character escape, escape us. */
			if (last == '\\')
				putchar('e');
		}
		break;
	case NODE_TITLE:
		if (pn->parent->node == NODE_BOOKINFO)
			macro_open(p, "Nd");
		break;
	case NODE_TYPE:
		macro_open(p, "Vt");
		break;
	case NODE_USERINPUT:
		macro_open(p, "Li");
		break;
	case NODE_VARIABLELIST:
		pnode_printvariablelist(p, pn);
		break;
	case NODE_VARLISTENTRY:
		pnode_printvarlistentry(p, pn);
		break;
	case NODE_VARNAME:
		macro_open(p, "Va");
		break;
	default:
		break;
	}

	TAILQ_FOREACH(pp, &pn->childq, child)
		pnode_print(p, pp);

	switch (pn->node) {
	case NODE_INFORMALEQUATION:
		macro_line(p, "EN");
		break;
	case NODE_INLINEEQUATION:
		fputs("$ ", stdout);
		p->linestate = sv;
		break;
	case NODE_MML_MROW:
	case NODE_MML_MI:
	case NODE_MML_MN:
	case NODE_MML_MO:
		if (TAILQ_EMPTY(&pn->childq))
			break;
		fputs(" } ", stdout);
		break;
	case NODE_APPLICATION:
	case NODE_ARG:
	case NODE_AUTHOR:
	case NODE_CITEREFENTRY:
	case NODE_CITETITLE:
	case NODE_CODE:
	case NODE_COMMAND:
	case NODE_CONSTANT:
	case NODE_EDITOR:
	case NODE_EMAIL:
	case NODE_EMPHASIS:
	case NODE_ENVAR:
	case NODE_FILENAME:
	case NODE_FIRSTTERM:
	case NODE_FUNCTION:
	case NODE_FUNCSYNOPSISINFO:
	case NODE_KEYSYM:
	case NODE_LITERAL:
	case NODE_OPTION:
	case NODE_PARAMETER:
	case NODE_REPLACEABLE:
	case NODE_REFPURPOSE:
	case NODE_SGMLTAG:
	case NODE_STRUCTNAME:
	case NODE_TYPE:
	case NODE_USERINPUT:
	case NODE_VARNAME:
		if (sv != LINE_MACRO && p->linestate == LINE_MACRO)
			macro_closepunct(p, pn);
		break;
	case NODE_QUOTE:
		if (sv == LINE_NEW)
			macro_close(p);
		sv = p->linestate;
		macro_open(p, "Qc");
		if (sv == LINE_NEW)
			macro_close(p);
		break;
	case NODE_REFNAME:
		/*
		 * If we're in the NAME macro and we have multiple
		 * <refname> macros in sequence, then print out a
		 * trailing comma before the newline.
		 */
		if (pn->parent != NULL &&
		    pn->parent->node == NODE_REFNAMEDIV &&
		    TAILQ_NEXT(pn, child) != NULL &&
		    TAILQ_NEXT(pn, child)->node == NODE_REFNAME)
			macro_addarg(p, ",", ARG_SPACE);
		if (sv == LINE_NEW)
			macro_close(p);
		break;
	case NODE_PREFACE:
	case NODE_SECTION:
	case NODE_NOTE:
	case NODE_TIP:
	case NODE_CAUTION:
	case NODE_WARNING:
		p->level--;
		break;
	case NODE_LITERALLAYOUT:
	case NODE_PROGRAMLISTING:
	case NODE_SCREEN:
		macro_line(p, "Ed");
		break;
	case NODE_TITLE:
		if (pn->parent->node == NODE_BOOKINFO)
			macro_line(p, "Sh AUTHORS");
		break;
	default:
		break;
	}
}

void
ptree_print(struct ptree *tree)
{
	struct format	 formatter;

	formatter.level = 0;
	formatter.linestate = LINE_NEW;
	pnode_printprologue(&formatter, tree);
	pnode_print(&formatter, tree->root);
	if (formatter.linestate != LINE_NEW)
		putchar('\n');
}