/*

 * HTMLtree.c : implementation of access function for an HTML tree.

 *

 * See Copyright for the status of this software.

 *

 * daniel@veillard.com

 */

#define IN_LIBXML

#include "XmlEnglibxml.h"

#ifdef LIBXML_HTML_ENABLED

#include <string.h> /* for memset() only ! */

#ifdef HAVE_CTYPE_H

#include <ctype.h>

#endif

#ifdef HAVE_STDLIB_H

#include <stdlib.h>

#endif

#include "Libxml2_xmlmemory.h"

#include "Libxml2_HTMLparser.h"

#include "Libxml2_HTMLtree.h"

#include "Libxml2_entities.h"

#include "Libxml2_valid.h"

#include "Libxml2_xmlerror.h"

#include "Libxml2_parserInternals.h"

#include "Libxml2_globals.h"

#include "Libxml2_uri.h"

/************************************************************************

 *									*

 *   		Getting/Setting encoding meta tags			*

 *									*

 ************************************************************************/

/**

 * htmlGetMetaEncoding:

 * @doc:  the document

 * 

 * Encoding definition lookup in the Meta tags

 *

 * Returns the current encoding as flagged in the HTML source

 */

const xmlChar *

htmlGetMetaEncoding(htmlDocPtr doc) {

    htmlNodePtr cur;

    const xmlChar *content;

    const xmlChar *encoding;

    if (doc == NULL)

	return(NULL);

    cur = doc->children;

    /*

     * Search the html

     */

    while (cur != NULL) {

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

	    if (xmlStrEqual(cur->name, BAD_CAST"html"))

		break;

	    if (xmlStrEqual(cur->name, BAD_CAST"head"))

		goto found_head;

	    if (xmlStrEqual(cur->name, BAD_CAST"meta"))

		goto found_meta;

	}

	cur = cur->next;

    }

    if (cur == NULL)

	return(NULL);

    cur = cur->children;

    /*

     * Search the head

     */

    while (cur != NULL) {

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

	    if (xmlStrEqual(cur->name, BAD_CAST"head"))

		break;

	    if (xmlStrEqual(cur->name, BAD_CAST"meta"))

		goto found_meta;

	}

	cur = cur->next;

    }

    if (cur == NULL)

	return(NULL);

found_head:

    cur = cur->children;

    /*

     * Search the meta elements

     */

found_meta:

    while (cur != NULL) {

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

	    if (xmlStrEqual(cur->name, BAD_CAST"meta")) {

		xmlAttrPtr attr = cur->properties;

		int http;

		const xmlChar *value;

		content = NULL;

		http = 0;

		while (attr != NULL) {

		    if ((attr->children != NULL) &&

		        (attr->children->type == XML_TEXT_NODE) &&

		        (attr->children->next == NULL)) {

			value = attr->children->content;

			if ((!xmlStrcasecmp(attr->name, BAD_CAST"http-equiv"))

			 && (!xmlStrcasecmp(value, BAD_CAST"Content-Type")))

			    http = 1;

			else if ((value != NULL)

			 && (!xmlStrcasecmp(attr->name, BAD_CAST"content")))

			    content = value;

			if ((http != 0) && (content != NULL))

			    goto found_content;

		    }

		    attr = attr->next;

		}

	    }

	}

	cur = cur->next;

    }

    return(NULL);

found_content:

    encoding = xmlStrstr(content, BAD_CAST"charset=");

    if (encoding == NULL) 

	encoding = xmlStrstr(content, BAD_CAST"Charset=");

    if (encoding == NULL) 

	encoding = xmlStrstr(content, BAD_CAST"CHARSET=");

    if (encoding != NULL) {

	encoding += 8;

    } else {

	encoding = xmlStrstr(content, BAD_CAST"charset =");

	if (encoding == NULL) 

	    encoding = xmlStrstr(content, BAD_CAST"Charset =");

	if (encoding == NULL) 

	    encoding = xmlStrstr(content, BAD_CAST"CHARSET =");

	if (encoding != NULL)

	    encoding += 9;

    }

    if (encoding != NULL) {

	while ((*encoding == ' ') || (*encoding == '\t')) encoding++;

    }

    return(encoding);

}

/**

 * htmlSetMetaEncoding:

 * @doc:  the document

 * @encoding:  the encoding string

 * 

 * Sets the current encoding in the Meta tags

 * NOTE: this will not change the document content encoding, just

 * the META flag associated.

 *

 * Returns 0 in case of success and -1 in case of error

 */

int

htmlSetMetaEncoding(htmlDocPtr doc, const xmlChar *encoding) {

    htmlNodePtr cur, meta;

    const xmlChar *content;

    char newcontent[100];

    if (doc == NULL)

	return(-1);

    if (encoding != NULL) {

	snprintf(newcontent, sizeof(newcontent), "text/html; charset=%s",

                encoding);

	newcontent[sizeof(newcontent) - 1] = 0;

    }

    cur = doc->children;

    /*

     * Search the html

     */

    while (cur != NULL) {

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

	    if (xmlStrcasecmp(cur->name, BAD_CAST"html") == 0)

		break;

	    if (xmlStrcasecmp(cur->name, BAD_CAST"head") == 0)

		goto found_head;

	    if (xmlStrcasecmp(cur->name, BAD_CAST"meta") == 0)

		goto found_meta;

	}

	cur = cur->next;

    }

    if (cur == NULL)

	return(-1);

    cur = cur->children;

    /*

     * Search the head

     */

    while (cur != NULL) {

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

	    if (xmlStrcasecmp(cur->name, BAD_CAST"head") == 0)

		break;

	    if (xmlStrcasecmp(cur->name, BAD_CAST"meta") == 0)

		goto found_meta;

	}

	cur = cur->next;

    }

    if (cur == NULL)

	return(-1);

found_head:

    if (cur->children == NULL) {

	if (encoding == NULL)

	    return(0);

	meta = xmlNewDocNode(doc, NULL, BAD_CAST"meta", NULL);

	xmlAddChild(cur, meta);

	xmlNewProp(meta, BAD_CAST"http-equiv", BAD_CAST"Content-Type");

	xmlNewProp(meta, BAD_CAST"content", BAD_CAST newcontent);

        if ( OOM_FLAG )     //oom set in xmlNewProp

            return(-1);

	return(0);

    }

    cur = cur->children;

found_meta:

    if (encoding != NULL) {

	/*

	 * Create a new Meta element with the right attributes

	 */

	meta = xmlNewDocNode(doc, NULL, BAD_CAST"meta", NULL);

	xmlAddPrevSibling(cur, meta);

	xmlNewProp(meta, BAD_CAST"http-equiv", BAD_CAST"Content-Type");

	xmlNewProp(meta, BAD_CAST"content", BAD_CAST newcontent);

    }

    /*

     * Search and destroy all the remaining the meta elements carrying

     * encoding informations

     */

    while (cur != NULL) {

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

	    if (xmlStrcasecmp(cur->name, BAD_CAST"meta") == 0) {

		xmlAttrPtr attr = cur->properties;

		int http;

		const xmlChar *value;

		content = NULL;

		http = 0;

		while (attr != NULL) {

		    if ((attr->children != NULL) &&

		        (attr->children->type == XML_TEXT_NODE) &&

		        (attr->children->next == NULL)) {

			value = attr->children->content;

			if ((!xmlStrcasecmp(attr->name, BAD_CAST"http-equiv"))

			 && (!xmlStrcasecmp(value, BAD_CAST"Content-Type")))

			    http = 1;

			else 

                        {

                           if ((value != NULL) && 

				(!xmlStrcasecmp(attr->name, BAD_CAST"content")))

			      content = value;

                        }

		        if ((http != 0) && (content != NULL))

			    break;

		    }

		    attr = attr->next;

		}

		if ((http != 0) && (content != NULL)) {

		    meta = cur;

		    cur = cur->next;

		    xmlUnlinkNode(meta);

                    xmlFreeNode(meta);

		    continue;

		}

	    }

	}

	cur = cur->next;

    }

    return(0);

}

/**

 * booleanHTMLAttrs:

 *

 * These are the HTML attributes which will be output

 * in minimized form, i.e. <option selected="selected"> will be

 * output as <option selected>, as per XSLT 1.0 16.2 "HTML Output Method"

 *

 */

static const char* const htmlBooleanAttrs[] = {

  "checked", "compact", "declare", "defer", "disabled", "ismap",

  "multiple", "nohref", "noresize", "noshade", "nowrap", "readonly",

  "selected", NULL

};

/**

 * htmlIsBooleanAttr:

 * @name:  the name of the attribute to check

 *

 * Determine if a given attribute is a boolean attribute.

 * 

 * returns: false if the attribute is not boolean, true otherwise.

 */

int

htmlIsBooleanAttr(const xmlChar *name)

{

    int i = 0;

    while (htmlBooleanAttrs[i] != NULL) {

        if (xmlStrcasecmp((const xmlChar *)htmlBooleanAttrs[i], name) == 0)

            return 1;

        i++;

    }

    return 0;

}

#ifdef LIBXML_OUTPUT_ENABLED

/************************************************************************

 *									*

 * 			Output error handlers				*

 *									*

 ************************************************************************/

/**

 * htmlSaveErrMemory:

 * @extra:  extra informations

 *

 * Handle an out of memory condition

 */

static void

htmlSaveErrMemory(const char *extra)

{

    __xmlSimpleError(XML_FROM_OUTPUT, XML_ERR_NO_MEMORY, NULL, NULL, extra);

}

/**

 * htmlSaveErr:

 * @code:  the error number

 * @node:  the location of the error.

 * @extra:  extra informations

 *

 * Handle an out of memory condition

 */

static void

htmlSaveErr(int code, xmlNodePtr node, const char *extra)

{

    const char *msg = NULL;

    switch(code) {

        case XML_SAVE_NOT_UTF8:

	    msg = "string is not in UTF-8";

	    break;

	case XML_SAVE_CHAR_INVALID:

	    msg = "invalid character value";

	    break;

	case XML_SAVE_UNKNOWN_ENCODING:

	    msg = "unknown encoding %s";

	    break;

	case XML_SAVE_NO_DOCTYPE:

	    msg = "HTML has no DOCTYPE";

	    break;

	default:

	    msg = "unexpected error number";

    }

    __xmlSimpleError(XML_FROM_OUTPUT, code, node, msg, extra);

}

/************************************************************************

 *									*

 *   		Dumping HTML tree content to a simple buffer		*

 *									*

 ************************************************************************/

static int

htmlNodeDumpFormat(xmlBufferPtr buf, xmlDocPtr doc, xmlNodePtr cur,

	           int format);

/**

 * htmlNodeDumpFormat:

 * @buf:  the HTML buffer output

 * @doc:  the document

 * @cur:  the current node

 * @format:  should formatting spaces been added

 *

 * Dump an HTML node, recursive behaviour,children are printed too.

 *

 * Returns the number of byte written or -1 in case of error

 */

static int

htmlNodeDumpFormat(xmlBufferPtr buf, xmlDocPtr doc, xmlNodePtr cur,

	           int format) {

    unsigned int use;

    int ret;

    xmlOutputBufferPtr outbuf;

    if (cur == NULL) {

	return (-1);

    }

    if (buf == NULL) {

	return (-1);

    }

    outbuf = (xmlOutputBufferPtr) xmlMalloc(sizeof(xmlOutputBuffer));

    if (outbuf == NULL) {

        htmlSaveErrMemory("allocating HTML output buffer");

	return (-1);

    }

    memset(outbuf, 0, (size_t) sizeof(xmlOutputBuffer));

    outbuf->buffer = buf;

    outbuf->encoder = NULL;

    outbuf->writecallback = NULL;

    outbuf->closecallback = NULL;

    outbuf->context = NULL;

    outbuf->written = 0;

    use = buf->use;

    htmlNodeDumpFormatOutput(outbuf, doc, cur, NULL, format);

    xmlFree(outbuf);

    ret = buf->use - use;

    return (ret);

}

/**

 * htmlNodeDump:

 * @buf:  the HTML buffer output

 * @doc:  the document

 * @cur:  the current node

 *

 * Dump an HTML node, recursive behaviour,children are printed too,

 * and formatting returns are added.

 *

 * Returns the number of byte written or -1 in case of error

 */

int

htmlNodeDump(xmlBufferPtr buf, xmlDocPtr doc, xmlNodePtr cur) {

    xmlInitParser();

    return(htmlNodeDumpFormat(buf, doc, cur, 1));

}

/**

 * htmlNodeDumpFileFormat:

 * @out:  the FILE pointer

 * @doc:  the document

 * @cur:  the current node

 * @encoding: the document encoding

 * @format:  should formatting spaces been added

 *

 * Dump an HTML node, recursive behaviour,children are printed too.

 *

 * TODO: if encoding == NULL try to save in the doc encoding

 *

 * returns: the number of byte written or -1 in case of failure.

 */

int

htmlNodeDumpFileFormat(FILE *out, xmlDocPtr doc,

	               xmlNodePtr cur, const char *encoding, int format) {

    xmlOutputBufferPtr buf;

    xmlCharEncodingHandlerPtr handler = NULL;

    int ret;

    xmlInitParser();

    if (encoding != NULL) {

	xmlCharEncoding enc;

	enc = xmlParseCharEncoding(encoding);

	if (enc != XML_CHAR_ENCODING_UTF8) {

	    handler = xmlFindCharEncodingHandler(encoding);

	    if (handler == NULL)

		return(-1);

	}

    }

    /*

     * Fallback to HTML or ASCII when the encoding is unspecified

     */

    if (handler == NULL)

	handler = xmlFindCharEncodingHandler("HTML");

    if (handler == NULL)

	handler = xmlFindCharEncodingHandler("ascii");

    /* 

     * save the content to a temp buffer.

     */

    buf = xmlOutputBufferCreateFile(out, handler);

    if (buf == NULL) return(0);

    htmlNodeDumpFormatOutput(buf, doc, cur, encoding, format);

    ret = xmlOutputBufferClose(buf);

    return(ret);

}

/**

 * htmlNodeDumpFile:

 * @out:  the FILE pointer

 * @doc:  the document

 * @cur:  the current node

 *

 * Dump an HTML node, recursive behaviour,children are printed too,

 * and formatting returns are added.

 */

void

htmlNodeDumpFile(FILE *out, xmlDocPtr doc, xmlNodePtr cur) {

    htmlNodeDumpFileFormat(out, doc, cur, NULL, 1);

}

/**

 * htmlDocDumpMemory:

 * @cur:  the document

 * @mem:  OUT: the memory pointer

 * @size:  OUT: the memory length

 *

 * Dump an HTML document in memory and return the xmlChar * and it's size.

 * It's up to the caller to free the memory.

 */

void

htmlDocDumpMemory(xmlDocPtr cur, xmlChar**mem, int *size) {

    xmlOutputBufferPtr buf;

    xmlCharEncodingHandlerPtr handler = NULL;

    const char *encoding;

    xmlInitParser();

    if (cur == NULL) {