/*
 * documents.c: Implementation of the documents handling
 *
 * See Copyright for the status of this software.
 *
 * daniel@veillard.com
 */

#define IN_LIBXSLT
#include "libxslt.h"

#include <string.h>

#include <libxml/xmlmemory.h>
#include <libxml/tree.h>
#include <libxml/hash.h>
#include "xslt.h"
#include "xsltInternals.h"
#include "xsltutils.h"
#include "documents.h"
#include "transform.h"
#include "imports.h"
#include "keys.h"
#include "security.h"

#ifdef LIBXML_XINCLUDE_ENABLED
#include <libxml/xinclude.h>
#endif

#define WITH_XSLT_DEBUG_DOCUMENTS

#ifdef WITH_XSLT_DEBUG
#define WITH_XSLT_DEBUG_DOCUMENTS
#endif

/************************************************************************
 *									*
 *			Module interfaces				*
 *									*
 ************************************************************************/

/**
 * xsltNewDocument:
 * @ctxt: an XSLT transformation context (or NULL)
 * @doc:  a parsed XML document
 *
 * Register a new document, apply key computations
 *
 * Returns a handler to the document
 */
xsltDocumentPtr	
xsltNewDocument(xsltTransformContextPtr ctxt, xmlDocPtr doc) {
    xsltDocumentPtr cur;

    cur = (xsltDocumentPtr) xmlMalloc(sizeof(xsltDocument));
    if (cur == NULL) {
	xsltTransformError(ctxt, NULL, (xmlNodePtr) doc,
		"xsltNewDocument : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0, sizeof(xsltDocument));
    cur->doc = doc;
    if (ctxt != NULL) {
	cur->next = ctxt->docList;
	ctxt->docList = cur;
	xsltInitCtxtKeys(ctxt, cur);
    }
    return(cur);
}

/**
 * xsltNewStyleDocument:
 * @style: an XSLT style sheet
 * @doc:  a parsed XML document
 *
 * Register a new document, apply key computations
 *
 * Returns a handler to the document
 */
xsltDocumentPtr	
xsltNewStyleDocument(xsltStylesheetPtr style, xmlDocPtr doc) {
    xsltDocumentPtr cur;

    cur = (xsltDocumentPtr) xmlMalloc(sizeof(xsltDocument));
    if (cur == NULL) {
	xsltTransformError(NULL, style, (xmlNodePtr) doc,
		"xsltNewStyleDocument : malloc failed\n");
	return(NULL);
    }
    memset(cur, 0, sizeof(xsltDocument));
    cur->doc = doc;
    if (style != NULL) {
	cur->next = style->docList;
	style->docList = cur;
    }
    return(cur);
}

/**
 * xsltFreeStyleDocuments:
 * @style: an XSLT style sheet
 *
 * Free up all the space used by the loaded documents
 */
void	
xsltFreeStyleDocuments(xsltStylesheetPtr style) {
    xsltDocumentPtr doc, cur;

    cur = style->docList;
    while (cur != NULL) {
	doc = cur;
	cur = cur->next;
	xsltFreeDocumentKeys(doc);
	if (!doc->main)
	    xmlFreeDoc(doc->doc);
        xmlFree(doc);
    }
}

/**
 * xsltFreeDocuments:
 * @ctxt: an XSLT transformation context
 *
 * Free up all the space used by the loaded documents
 */
void	
xsltFreeDocuments(xsltTransformContextPtr ctxt) {
    xsltDocumentPtr doc, cur;

    cur = ctxt->docList;
    while (cur != NULL) {
	doc = cur;
	cur = cur->next;
	xsltFreeDocumentKeys(doc);
	if (!doc->main)
	    xmlFreeDoc(doc->doc);
        xmlFree(doc);
    }
    cur = ctxt->styleList;
    while (cur != NULL) {
	doc = cur;
	cur = cur->next;
	xsltFreeDocumentKeys(doc);
	if (!doc->main)
	    xmlFreeDoc(doc->doc);
        xmlFree(doc);
    }
}


/**
 * xsltLoadDocument:
 * @ctxt: an XSLT transformation context
 * @URI:  the computed URI of the document
 *
 * Try to load a document (not a stylesheet)
 * within the XSLT transformation context
 *
 * Returns the new xsltDocumentPtr or NULL in case of error
 */
xsltDocumentPtr	
xsltLoadDocument(xsltTransformContextPtr ctxt, const xmlChar *URI) {
    xsltDocumentPtr ret;
    xmlDocPtr doc;

    if ((ctxt == NULL) || (URI == NULL))
	return(NULL);

    /*
     * Security framework check
     */
    if (ctxt->sec != NULL) {
	int res;
	
	res = xsltCheckRead(ctxt->sec, ctxt, URI);
	if (res == 0) {
	    xsltTransformError(ctxt, NULL, NULL,
		 "xsltLoadDocument: read rights for %s denied\n",
			     URI);
	    return(NULL);
	}
    }

    /*
     * Walk the context list to find the document if preparsed
     */
    ret = ctxt->docList;
    while (ret != NULL) {
	if ((ret->doc != NULL) && (ret->doc->URL != NULL) &&
	    (xmlStrEqual(ret->doc->URL, URI)))
	    return(ret);
	ret = ret->next;
    }

    doc = xmlParseFile((const char *) URI);
    if (doc == NULL)
	return(NULL);

    if (ctxt->xinclude != 0) {
#ifdef LIBXML_XINCLUDE_ENABLED
	xmlXIncludeProcess(doc);
#else
	xsltTransformError(ctxt, NULL, NULL,
	    "xsltLoadDocument(%s) : XInclude processing not compiled in\n",
	                 URI);
#endif
    }
    /*
     * Apply white-space stripping if asked for
     */
    if (xsltNeedElemSpaceHandling(ctxt))
	xsltApplyStripSpaces(ctxt, xmlDocGetRootElement(doc));

    ret = xsltNewDocument(ctxt, doc);
    return(ret);
}

/**
 * xsltLoadStyleDocument:
 * @style: an XSLT style sheet
 * @URI:  the computed URI of the document
 *
 * Try to load a stylesheet document within the XSLT transformation context
 *
 * Returns the new xsltDocumentPtr or NULL in case of error
 */
xsltDocumentPtr	
xsltLoadStyleDocument(xsltStylesheetPtr style, const xmlChar *URI) {
    xsltDocumentPtr ret;
    xmlDocPtr doc;
    xsltSecurityPrefsPtr sec;

    if ((style == NULL) || (URI == NULL))
	return(NULL);

    /*
     * Security framework check
     */
    sec = xsltGetDefaultSecurityPrefs();
    if (sec != NULL) {
	int res;

	res = xsltCheckRead(sec, NULL, URI);
	if (res == 0) {
	    xsltTransformError(NULL, NULL, NULL,
		 "xsltLoadStyleDocument: read rights for %s denied\n",
			     URI);
	    return(NULL);
	}
    }

    /*
     * Walk the context list to find the document if preparsed
     */
    ret = style->docList;
    while (ret != NULL) {
	if ((ret->doc != NULL) && (ret->doc->URL != NULL) &&
	    (xmlStrEqual(ret->doc->URL, URI)))
	    return(ret);
	ret = ret->next;
    }

    doc = xmlParseFile((const char *) URI);
    if (doc == NULL)
	return(NULL);

    ret = xsltNewStyleDocument(style, doc);
    return(ret);
}

/**
 * xsltFindDocument:
 * @ctxt: an XSLT transformation context
 * @doc: a parsed XML document
 *
 * Try to find a document within the XSLT transformation context
 *
 * Returns the desired xsltDocumentPtr or NULL in case of error
 */
xsltDocumentPtr
xsltFindDocument (xsltTransformContextPtr ctxt, xmlDocPtr doc) {
    xsltDocumentPtr ret;

    if ((ctxt == NULL) || (doc == NULL))
	return(NULL);

    /*
     * Walk the context list to find the document
     */
    ret = ctxt->docList;
    while (ret != NULL) {
	if (ret->doc == doc)
	    return(ret);
	ret = ret->next;
    }
    if (doc == ctxt->style->doc)
	return(ctxt->document);
    return(NULL);
}