/* $Id: node.c,v 1.9 2019/04/12 04:39:24 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 <stdlib.h>
#include <string.h>

#include "node.h"

/*
 * The implementation of the DocBook syntax tree.
 */

static	const char *const attrkeys[ATTRKEY__MAX] = {
	"choice",
	"class",
	"close",
	"cols",
	"DEFINITION",
	"endterm",
	"href",
	"id",
	"linkend",
	"NAME",
	"open",
	"PUBLIC",
	"rep",
	"SYSTEM",
	"url",
	"xlink:href"
};

static	const char *const attrvals[ATTRVAL__MAX] = {
	"monospaced",
	"norepeat",
	"opt",
	"plain",
	"repeat",
	"req"
};

enum attrkey
attrkey_parse(const char *name)
{
	enum attrkey	 key;

	for (key = 0; key < ATTRKEY__MAX; key++)
		if (strcmp(name, attrkeys[key]) == 0)
			break;
	return key;
}

enum attrval
attrval_parse(const char *name)
{
	enum attrval	 val;

	for (val = 0; val < ATTRVAL__MAX; val++)
		if (strcmp(name, attrvals[val]) == 0)
			break;
	return val;
}

struct pnode *
pnode_alloc(struct pnode *np)
{
	struct pnode	*n;

	if ((n = calloc(1, sizeof(*n))) != NULL) {
		TAILQ_INIT(&n->childq);
		TAILQ_INIT(&n->attrq);
		if ((n->parent = np) != NULL)
			TAILQ_INSERT_TAIL(&np->childq, n, child);
	}
	return n;
}

/*
 * Recursively free a node (NULL is ok).
 */
static void
pnode_free(struct pnode *n)
{
	struct pnode	*nc;
	struct pattr	*a;

	if (n == NULL)
		return;

	while ((nc = TAILQ_FIRST(&n->childq)) != NULL) {
		TAILQ_REMOVE(&n->childq, nc, child);
		pnode_free(nc);
	}
	while ((a = TAILQ_FIRST(&n->attrq)) != NULL) {
		TAILQ_REMOVE(&n->attrq, a, child);
		free(a->rawval);
		free(a);
	}
	free(n->b);
	free(n);
}

/*
 * Unlink a node from its parent and pnode_free() it.
 */
void
pnode_unlink(struct pnode *n)
{
	if (n == NULL)
		return;
	if (n->parent != NULL)
		TAILQ_REMOVE(&n->parent->childq, n, child);
	pnode_free(n);
}

/*
 * Unlink all children of a node and pnode_free() them.
 */
void
pnode_unlinksub(struct pnode *n)
{
	while (TAILQ_EMPTY(&n->childq) == 0)
		pnode_unlink(TAILQ_FIRST(&n->childq));
}

/*
 * Retrieve an enumeration attribute from a node.
 * Return ATTRVAL__MAX if the node has no such attribute.
 */
enum attrval
pnode_getattr(struct pnode *n, enum attrkey key)
{
	struct pattr	*a;

	if (n == NULL)
		return ATTRVAL__MAX;
	TAILQ_FOREACH(a, &n->attrq, child)
		if (a->key == key)
			return a->val;
	return ATTRVAL__MAX;
}

/*
 * Retrieve an attribute string from a node.
 * Return defval if the node has no such attribute.
 */
const char *
pnode_getattr_raw(struct pnode *n, enum attrkey key, const char *defval)
{
	struct pattr	*a;

	if (n == NULL)
		return defval;
	TAILQ_FOREACH(a, &n->attrq, child)
		if (a->key == key)
			return a->val != ATTRVAL__MAX ? attrvals[a->val] :
			    a->rawval != NULL ? a->rawval : defval;
	return defval;
}

/*
 * Recursively search and return the first instance of "node".
 */
struct pnode *
pnode_findfirst(struct pnode *n, enum nodeid node)
{
	struct pnode	*nc, *res;

	if (n->node == node)
		return n;
	TAILQ_FOREACH(nc, &n->childq, child)
		if ((res = pnode_findfirst(nc, node)) != NULL)
			return res;
	return NULL;
}