/** 

 * XML Security Library (http://www.aleksey.com/xmlsec).

 *

 * Enchanced nodes set

 *

 * This is free software; see Copyright file in the source

 * distribution for preciese wording.

 * 

 * Copyright (C) 2002-2003 Aleksey Sanin <aleksey@aleksey.com>

 * Portion Copyright © 2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. 

 */

#include "xmlsec_globals.h"

#include <stdlib.h>

#include <string.h>

#include <libxml2_tree.h>

#include <libxml2_xpath.h>

#include <libxml2_xpathinternals.h>

#include <libxml2_globals.h>

#include "xmlsec_xmlsec.h"

#include "xmlsec_nodeset.h"

#include "xmlsec_errors.h"

#define xmlSecGetParent(node)           \

    (((node)->type != XML_NAMESPACE_DECL) ? \

        (node)->parent : \

        (xmlNodePtr)((xmlNsPtr)(node))->next)

static int	xmlSecNodeSetOneContains		(xmlSecNodeSetPtr nset, 

							 xmlNodePtr node, 

							 xmlNodePtr parent);

static int	xmlSecNodeSetWalkRecursive		(xmlSecNodeSetPtr nset, 

							 xmlSecNodeSetWalkCallback walkFunc, 

							 void* data, 

							 xmlNodePtr cur, 

							 xmlNodePtr parent);

/**

 * xmlSecNodeSetCreate:

 * @doc: 		the pointer to parent XML document.

 * @nodes: 		the list of nodes.

 * @type: 		the nodes set type.

 *

 * Creates new nodes set. Caller is responsible for freeng returend object

 * by calling #xmlSecNodeSetDestroy function.

 *

 * Returns pointer to newly allocated node set or NULL if an error occurs.

 */

EXPORT_C

xmlSecNodeSetPtr

xmlSecNodeSetCreate(xmlDocPtr doc, xmlNodeSetPtr nodes, xmlSecNodeSetType type) {

    xmlSecNodeSetPtr nset;

    nset = (xmlSecNodeSetPtr)xmlMalloc(sizeof(xmlSecNodeSet));

    if(nset == NULL) { 

	xmlSecError(XMLSEC_ERRORS_HERE,

		    NULL,

		    NULL,

		    XMLSEC_ERRORS_R_MALLOC_FAILED,

		    "sizeof(xmlSecNodeSet)=%d",

		    sizeof(xmlSecNodeSet));

	return(NULL);

    }

    memset(nset, 0,  sizeof(xmlSecNodeSet));

    nset->doc 	= doc;

    nset->nodes = nodes;

    nset->type	= type;

    nset->next 	= nset->prev = nset;

    return(nset);

}

/**

 * xmlSecNodeSetDestroy:

 * @nset: 		the pointer to node set.

 *

 * Destroys the nodes set created with #xmlSecNodeSetCreate function.

 */

EXPORT_C

void

xmlSecNodeSetDestroy(xmlSecNodeSetPtr nset) {

    xmlSecNodeSetPtr tmp;

    xmlSecAssert(nset != NULL);

    while((tmp = nset) != NULL) {

	if((nset->next != NULL) && (nset->next != nset)) {

	    nset->next->prev = nset->prev;

	    nset->prev->next = nset->next;	    

	    nset = nset->next;

	} else {

	    nset = NULL;

	}

	if(tmp->nodes != NULL) {

    	    xmlXPathFreeNodeSet(tmp->nodes);

	}

	if(tmp->children != NULL) {

	    xmlSecNodeSetDestroy(tmp->children);

	}

	if((tmp->doc != NULL) && (tmp->destroyDoc != 0)) {

	    xmlFreeDoc(tmp->doc);

	}

	memset(tmp, 0,  sizeof(xmlSecNodeSet));

        xmlFree(tmp);

    }

}

/**

 * xmlSecNodeSetDocDestroy:

 * @nset: 		the pointer to node set.

 *

 * Instructs node set to destroy nodes parent doc when node set is destroyed.

 */

EXPORT_C

void 

xmlSecNodeSetDocDestroy(xmlSecNodeSetPtr nset) {

    xmlSecAssert(nset != NULL);

    nset->destroyDoc = 1;

}

static int

xmlSecNodeSetOneContains(xmlSecNodeSetPtr nset, xmlNodePtr node, xmlNodePtr parent) {

    int in_nodes_set = 1;

    xmlSecAssert2(nset != NULL, 0);

    xmlSecAssert2(node != NULL, 0);

    /* special cases: */

    switch(nset->type) {

	case xmlSecNodeSetTreeWithoutComments:

        case xmlSecNodeSetTreeWithoutCommentsInvert:

	    if(node->type == XML_COMMENT_NODE) {

		return(0);

	    }

	    break;

	case xmlSecNodeSetList:

	    return(xmlSecNodeSetContains(nset->children, node, parent));

	default:

	    break;

    }

    if(nset->nodes != NULL) {

	if(node->type != XML_NAMESPACE_DECL) {

	    in_nodes_set = xmlXPathNodeSetContains(nset->nodes, node);

	} else {

	    xmlNs ns;

	    memcpy(&ns, node, sizeof(ns)); 

	    if((parent != NULL) && (parent->type == XML_ATTRIBUTE_NODE)) {

		ns.next = (xmlNsPtr)parent->parent;

	    } else {

		ns.next = (xmlNsPtr)parent; 

	    }

	    /* 

	     * If the input is an XPath node-set, then the node-set must explicitly 

	     * contain every node to be rendered to the canonical form.

	     */

	    in_nodes_set = (xmlXPathNodeSetContains(nset->nodes, (xmlNodePtr)&ns));

	}

    }

    switch(nset->type) {

    case xmlSecNodeSetNormal:

	return(in_nodes_set);

    case xmlSecNodeSetInvert:

	return(!in_nodes_set);

    case xmlSecNodeSetTree:

    case xmlSecNodeSetTreeWithoutComments:

	if(in_nodes_set) {

	    return(1);

	}

	if((parent != NULL) && (parent->type == XML_ELEMENT_NODE)) {

	    return(xmlSecNodeSetOneContains(nset, parent, parent->parent));

	}

	return(0);

    case xmlSecNodeSetTreeInvert:

    case xmlSecNodeSetTreeWithoutCommentsInvert:

	if(in_nodes_set) {

	    return(0);

	}

	if((parent != NULL) && (parent->type == XML_ELEMENT_NODE)) {

	    return(xmlSecNodeSetOneContains(nset, parent, parent->parent));

	}

	return(1);

    default:

	xmlSecError(XMLSEC_ERRORS_HERE,

		    NULL,

		    NULL,

		    XMLSEC_ERRORS_R_INVALID_TYPE,

		    "type=%d", nset->type);

    }

    return(0);

}

/**

 * xmlSecNodeSetContains:

 * @nset: 		the pointer to node set.

 * @node: 		the pointer to XML node to check.

 * @parent: 		the pointer to @node parent node.

 *

 * Checks whether the @node is in the nodes set or not.

 *

 * Returns 1 if the @node is in the nodes set @nset, 0 if it is not

 * and a negative value if an error occurs.

 */

EXPORT_C

int

xmlSecNodeSetContains(xmlSecNodeSetPtr nset, xmlNodePtr node, xmlNodePtr parent) {

    int status = 1;

    xmlSecNodeSetPtr cur;

    xmlSecAssert2(node != NULL, 0);

    /* special cases: */

    if(nset == NULL) {

	return(1);

    }

    status = 1;

    cur = nset;

    do {

	switch(cur->op) {

	case xmlSecNodeSetIntersection:

	    if(status && !xmlSecNodeSetOneContains(cur, node, parent)) {

		status = 0;

	    }

    	    break;

	case xmlSecNodeSetSubtraction:

	    if(status && xmlSecNodeSetOneContains(cur, node, parent)) {

		status = 0;

	    }

	    break;

	case xmlSecNodeSetUnion:

	    if(!status && xmlSecNodeSetOneContains(cur, node, parent)) {

		status = 1;

	    }	

	    break;

	default:

	    xmlSecError(XMLSEC_ERRORS_HERE,

			NULL,

			NULL,

			XMLSEC_ERRORS_R_INVALID_OPERATION,

			"operation=%d", cur->op);

	    return(-1);

	}

	cur = cur->next;

    } while(cur != nset);

    return(status);

}

/**

 * xmlSecNodeSetAdd:

 * @nset: 		the pointer to currrent nodes set (or NULL).

 * @newNSet: 		the pointer to new nodes set.

 * @op: 		the operation type.

 *

 * Adds @newNSet to the @nset using operation @op. 

 *

 * Returns the pointer to combined nodes set or NULL if an error 

 * occurs.

 */

EXPORT_C

xmlSecNodeSetPtr	

xmlSecNodeSetAdd(xmlSecNodeSetPtr nset, xmlSecNodeSetPtr newNSet, 

		 xmlSecNodeSetOp op) {

    xmlSecAssert2(newNSet != NULL, NULL);

    xmlSecAssert2(newNSet->next == newNSet, NULL);

    newNSet->op	= op;

    if(nset == NULL) {

	return(newNSet);

    }

    newNSet->next = nset;

    newNSet->prev = nset->prev;

    nset->prev->next = newNSet;

    nset->prev 	     = newNSet;

    return(nset);

}

/**

 * xmlSecNodeSetAddList:

 * @nset: 		the pointer to currrent nodes set (or NULL).

 * @newNSet: 		the pointer to new nodes set.

 * @op: 		the operation type.

 *

 * Adds @newNSet to the @nset as child using operation @op. 

 *

 * Returns the pointer to combined nodes set or NULL if an error 

 * occurs.

 */

EXPORT_C

xmlSecNodeSetPtr	

xmlSecNodeSetAddList(xmlSecNodeSetPtr nset, xmlSecNodeSetPtr newNSet, xmlSecNodeSetOp op) {

    xmlSecNodeSetPtr tmp1, tmp2;

    xmlSecAssert2(newNSet != NULL, NULL);

    tmp1 = xmlSecNodeSetCreate(newNSet->doc, NULL, xmlSecNodeSetList);

    if(tmp1 == NULL) {

	xmlSecError(XMLSEC_ERRORS_HERE,

		    NULL,

		    "xmlSecNodeSetCreate",

		    XMLSEC_ERRORS_R_XMLSEC_FAILED,

		    XMLSEC_ERRORS_NO_MESSAGE);

	return(NULL);

    }

    tmp1->children = newNSet;

    tmp2 = xmlSecNodeSetAdd(nset, tmp1, op);

    if(tmp2 == NULL) {

	xmlSecError(XMLSEC_ERRORS_HERE,

		    NULL,

		    "xmlSecNodeSetAdd",

		    XMLSEC_ERRORS_R_XMLSEC_FAILED,

		    XMLSEC_ERRORS_NO_MESSAGE);

	xmlSecNodeSetDestroy(tmp1);

	return(NULL);

    }

    return(tmp2);

}

/**

 * xmlSecNodeSetWalk:

 * @nset: 		the pointer to node set.

 * @walkFunc: 		the callback functions.

 * @data: 		the application specific data passed to the @walkFunc.

 *

 * Calls the function @walkFunc once per each node in the nodes set @nset.

 * If the @walkFunc returns a negative value, then the walk procedure 

 * is interrupted.

 *

 * Returns 0 on success or a negative value if an error occurs.

 */

EXPORT_C

int

xmlSecNodeSetWalk(xmlSecNodeSetPtr nset, xmlSecNodeSetWalkCallback walkFunc, void* data) {

    xmlNodePtr cur;

    int ret = 0;

    xmlSecAssert2(nset != NULL, -1);

    xmlSecAssert2(nset->doc != NULL, -1);

    xmlSecAssert2(walkFunc != NULL, -1);

    /* special cases */

    if(nset->nodes != NULL) {

	int i;

	switch(nset->type) {

	case xmlSecNodeSetNormal:

	case xmlSecNodeSetTree:

	case xmlSecNodeSetTreeWithoutComments:

	    for(i = 0; (ret >= 0) && (i < nset->nodes->nodeNr); ++i) {

		ret = xmlSecNodeSetWalkRecursive(nset, walkFunc, data, 

		    nset->nodes->nodeTab[i], 

		    xmlSecGetParent(nset->nodes->nodeTab[i]));

	    }

	    return(ret);

	default:

	    break;

	}

    }

    for(cur = nset->doc->children; (cur != NULL) && (ret >= 0); cur = cur->next) {

	ret = xmlSecNodeSetWalkRecursive(nset, walkFunc, data, cur, xmlSecGetParent(cur));

    }

    return(ret);

}

static int

xmlSecNodeSetWalkRecursive(xmlSecNodeSetPtr nset, xmlSecNodeSetWalkCallback walkFunc, 

			    void* data, xmlNodePtr cur, xmlNodePtr parent) {

    int ret;

    xmlSecAssert2(nset != NULL, -1);

    xmlSecAssert2(cur != NULL, -1);

    xmlSecAssert2(walkFunc != NULL, -1);

    /* the node itself */

    if(xmlSecNodeSetContains(nset, cur, parent)) {

	ret = walkFunc(nset, cur, parent, data);

	if(ret < 0) {

	    return(ret);

	}

    }

    /* element node has attributes, namespaces  */	

    if(cur->type == XML_ELEMENT_NODE) {

        xmlAttrPtr attr;

	xmlNodePtr node;

	xmlNsPtr ns, tmp;

        attr = (xmlAttrPtr)cur->properties;

        while(attr != NULL) {

	    if(xmlSecNodeSetContains(nset, (xmlNodePtr)attr, cur)) {

		ret = walkFunc(nset, (xmlNodePtr)attr, cur, data);

		if(ret < 0) {

		    return(ret);

		}

	    }

	    attr = attr->next;

	}

	node = cur;

	while(node != NULL) {

    	    ns = node->nsDef;

    	    while(ns != NULL) {

		tmp = xmlSearchNs(nset->doc, cur, ns->prefix);

		if((tmp == ns) && xmlSecNodeSetContains(nset, (xmlNodePtr)ns, cur)) {

		    ret = walkFunc(nset, (xmlNodePtr)ns, cur, data);

		    if(ret < 0) {

			return(ret);

		    }

		}

		ns = ns->next;

	    }

	    node = node->parent;

	}

    }

    /* element and document nodes have children */

    if((cur->type == XML_ELEMENT_NODE) || (cur->type == XML_DOCUMENT_NODE)) {

	xmlNodePtr node;

	node = cur->children;

	while(node != NULL) {

	    ret = xmlSecNodeSetWalkRecursive(nset, walkFunc, data, node, cur);

	    if(ret < 0) {

		return(ret);

	    }

	    node = node->next;

	}

    }

    return(0);

}

/**

 * xmlSecNodeSetGetChildren:

 * @doc: 		the pointer to an XML document.

 * @parent:	 	the pointer to parent XML node or NULL if we want to include all document nodes.

 * @withComments: 	the flag include  comments or not.

 * @invert: 		the "invert" flag.

 *

 * Creates a new nodes set that contains:

 *  - if @withComments is not 0 and @invert is 0:

 *    all nodes in the @parent subtree;

 *  - if @withComments is 0 and @invert is 0:

 *    all nodes in the @parent subtree except comment nodes;

 *  - if @withComments is not 0 and @invert not is 0:

 *    all nodes in the @doc except nodes in the @parent subtree;

 *  - if @withComments is 0 and @invert is 0:

 *    all nodes in the @doc except nodes in the @parent subtree 

 *    and comment nodes.

 *

 * Returns pointer to the newly created #xmlSecNodeSet structure

 * or NULL if an error occurs.

 */

EXPORT_C

xmlSecNodeSetPtr	

xmlSecNodeSetGetChildren(xmlDocPtr doc, const xmlNodePtr parent, int withComments, int invert) {

    xmlNodeSetPtr nodes;

    xmlSecNodeSetType type;

    xmlSecNodeSetPtr result = NULL;

    xmlSecAssert2(doc != NULL, NULL);

    nodes = xmlXPathNodeSetCreate(parent);

    if(nodes == NULL) {

	xmlSecError(XMLSEC_ERRORS_HERE,

		    NULL,

		    "xmlXPathNodeSetCreate",

		    XMLSEC_ERRORS_R_XML_FAILED,

		    XMLSEC_ERRORS_NO_MESSAGE);

	return(NULL);

    }	

    /* if parent is NULL then we add all the doc children */

    if(parent == NULL) {

	xmlNodePtr cur;

	for(cur = doc->children; cur != NULL; cur = cur->next) {

	    if(withComments || (cur->type != XML_COMMENT_NODE)) {

	        xmlXPathNodeSetAdd(nodes, cur);

	    }

	}

    }

    if(withComments && invert) {

	type = xmlSecNodeSetTreeInvert;

    } else if(withComments && !invert) {

	type = xmlSecNodeSetTree;

    } else if(!withComments && invert) {

	type = xmlSecNodeSetTreeWithoutCommentsInvert;

    } else { /* if(!withComments && !invert) */

	type = xmlSecNodeSetTreeWithoutComments;

    }

    result = xmlSecNodeSetCreate(doc, nodes, type);

    if ( !result )

        {

        xmlXPathFreeNodeSet( nodes );   

        }

    return result;

}

static int

xmlSecNodeSetDumpTextNodesWalkCallback(xmlSecNodeSetPtr nset, xmlNodePtr cur, 

				   xmlNodePtr parent, 

				   void* data) {

    xmlSecAssert2(nset != NULL, -1);

    xmlSecAssert2(cur != NULL, -1);

    xmlSecAssert2(data != NULL, -1);

    if(cur->type == XML_TEXT_NODE) {

	xmlOutputBufferWriteString((xmlOutputBufferPtr)data, 

				    (char*)(cur->content)); 

    }

    return(0);

}