<?php

/**
 * Implementation of Common Cartridge library based on
 * {@link http://www.imsglobal.org/cc/ IMS Common Cartridge Standard v1.2}
 *
 * @author Darko Miletic
 * @author Daniel Muhlrad (daniel.muhlrad@uvcms.com)
 * @version 1.0
 * @copyright 2009 {@link http://www.uvcms.com UVCMS e-learning}
 * @package cc_library
 *
 */

require_once('gral_lib/cssparser.php');

/**
 * Base XML class
 *
 */
class XMLGenericDocument {
    private $charset;
    /**
     * Document
     * @var DOMDocument
     */
    public $doc = null;
    /**
     *
     * Xpath
     * @var DOMXPath
     */
    protected $dxpath = null;
    protected $filename;
    private $filepath;
    private $isloaded = false;
    private $arrayPrefixNS = array();
    private $is_html = false;

    /**
     * @param string $value
     * @return string
     */
    public static function safexml($value) {
        $result = htmlspecialchars(html_entity_decode($value, ENT_QUOTES, 'UTF-8'),
                                   ENT_NOQUOTES,
                                   'UTF-8',
                                   false);
        return $result;
    }

    function __construct($ch = 'UTF-8', $validatenow = true) {
        $this->charset = $ch;
        $this->documentInit();
        $this->doc->validateOnParse = $validatenow;
    }

    function __destruct() {
        $this->dxpath = null;
        $this->doc    = null;
    }

    private function documentInit($withonCreate = true) {
        $hg = false;
        if ($this->isloaded) {
            $guardstate = $this->doc->validateOnParse;
            $hg = true;
            unset($this->dxpath);
            unset($this->doc);
            $this->isloaded = false;
          }
        $this->doc = new DOMDocument("1.0", $this->charset);
        $this->doc->strictErrorChecking = true;
        if ($hg) {
            $this->doc->validateOnParse = $guardstate;
        }
        $this->doc->formatOutput = true;
        $this->doc->preserveWhiteSpace = true;
        if ($withonCreate) {
            $this->on_create();
        }
    }

    public function viewXML() {
        return $this->doc->saveXML();
    }

    public function registerNS($prefix, $nsuri) {
        $this->arrayPrefixNS[$prefix] = $nsuri;
    }

    public function load($fname) {
        // Sine xml will remain loaded should the repeated load fail we should recreate document to be empty.
        $this->documentInit(false);
        $this->isloaded = $this->doc->load($fname);
        if ($this->isloaded) {
            $this->filename = $fname;
            $this->processPath();
            $this->is_html = false;
        }
        return $this->on_load();
    }

    public function loadUrl($url) {
        $this->documentInit();
        $this->isloaded = true;
        $this->doc->loadXML( file_get_contents($url) );
        $this->is_html = false;
        return $this->on_load();
    }

    public function loadHTML($content) {
        $this->documentInit();
        $this->doc->validateOnParse = false;
        $this->isloaded = true;
        $this->doc->loadHTML($content);
        $this->is_html = true;
        return $this->on_load();
    }

    public function loadXML($content) {
        $this->documentInit();
        $this->doc->validateOnParse = false;
        $this->isloaded = true;
        $this->doc->load($content);
        $this->is_html = true;
        return $this->on_load();
    }

    public function loadHTMLFile($fname) {
        // Sine xml will remain loaded should the repeated load fail
        // we should recreate document to be empty.
        $this->documentInit();
        $this->doc->validateOnParse = false;
        $this->isloaded = $this->doc->loadHTMLFile($fname);
        if ($this->isloaded) {
            $this->filename = $fname;
            $this->processPath();
            $this->is_html=true;
        }
        return $this->on_load();
    }

    public function loadXMLFile($fname) {
        // Sine xml will remain loaded should the repeated load fail
        // we should recreate document to be empty.
        $this->documentInit();
        $this->doc->validateOnParse = false;
        $this->isloaded = $this->doc->load($fname);
        if ($this->isloaded) {
            $this->filename = $fname;
            $this->processPath();
            $this->is_html = true;
        }
        return $this->on_load();
    }


    public function loadString($content) {

        $this->doc = new DOMDocument("1.0", $this->charset);
        $content = '<virtualtag>'.$content.'</virtualtag>';
        $this->doc->loadXML($content);

        return true;
    }

    public function save() {
        $this->saveTo($this->filename);
    }

    public function saveTo($fname) {
        $status = false;
        if ($this->on_save()) {
            if ($this->is_html) {
                $this->doc->saveHTMLFile($fname);
            } else {
                $this->doc->save($fname);
            }
            $this->filename = $fname;
            $this->processPath();
            $status = true;
        }
        return $status;
    }

    public function validate() {
        return $this->doc->validate();
    }

    public function attributeValue($path, $attrname, $node = null) {
        $this->chkxpath();
        $result = null;
        $resultlist = null;
        if (is_null($node)) {
            $resultlist = $this->dxpath->query($path);
        } else {
            $resultlist = $this->dxpath->query($path, $node);
        }
        if (is_object($resultlist) && ($resultlist->length > 0) && $resultlist->item(0)->hasAttribute($attrname)) {
            $result = $resultlist->item(0)->getAttribute($attrname);
        }
        return $result;
    }

    /**
     *
     * Get's text value of the node based on xpath query
     * @param string $path
     * @param DOMNode $node
     * @param int $count
     * @return string
     */
    public function nodeValue($path, $node = null, $count = 1) {
        $nd = $this->node($path, $node, $count);
        return $this->nodeTextValue($nd);
    }

    /**
     *
     * Get's text value of the node
     * @param DOMNode $node
     * @return string
     */
    public function nodeTextValue($node) {
        $result = '';
        if (is_object($node)) {
            if ($node->hasChildNodes()) {
                $chnodesList = $node->childNodes;
                $types = array(XML_TEXT_NODE, XML_CDATA_SECTION_NODE);
                foreach ($chnodesList as $chnode) {
                    if (in_array($chnode->nodeType, $types)) {
                        $result .= $chnode->wholeText;
                    }
                }
            }
        }
        return $result;
    }

    /**
     *
     * Enter description here ...
     * @param string $path
     * @param DOMNode $nd
     * @param int $count
     * @return DOMNode
     */
    public function node($path, $nd = null, $count = 1) {
        $result = null;
        $resultlist = $this->nodeList($path,$nd);
        if (is_object($resultlist) && ($resultlist->length > 0)) {
            $result = $resultlist->item($count - 1);
        }
        return $result;
    }

    /**
     *
     * Enter description here ...
     * @param string $path
     * @param DOMNode $node
     * @return DOMNodeList
     */
    public function nodeList($path, $node = null) {

        $this->chkxpath();

        $resultlist = null;
        if (is_null($node)) {
            $resultlist = $this->dxpath->query($path);
        } else {
            $resultlist = $this->dxpath->query($path, $node);
        }
        return $resultlist;
    }

    /**
     *
     * Create new attribute
     * @param string $namespace
     * @param string $name
     * @param string $value
     * @return DOMAttr
     */
    public function create_attribute_ns($namespace, $name, $value = null) {
        $result = $this->doc->createAttributeNS($namespace, $name);
        if (!is_null($value)) {
            $result->nodeValue = $value;
        }
        return $result;
    }

    /**
     *
     * Create new attribute
     * @param string $name
     * @param string $value
     * @return DOMAttr
     */
    public function create_attribute($name, $value = null) {
        $result = $this->doc->createAttribute($name);
        if (!is_null($value)) {
            $result->nodeValue = $value;
        }
        return $result;
    }

    /**
     *
     * Adds new node
     * @param DOMNode $parentnode
     * @param string $namespace
     * @param string $name
     * @param string $value
     * @return DOMNode
     */
    public function append_new_element_ns(DOMNode &$parentnode, $namespace, $name, $value = null) {
        $newnode = null;
        if (is_null($value)) {
            $newnode = $this->doc->createElementNS($namespace, $name);
        } else {
            $newnode = $this->doc->createElementNS($namespace, $name, $value);
        }
        return $parentnode->appendChild($newnode);
    }

    /**
     *
     * New node with CDATA content
     * @param DOMNode $parentnode
     * @param string $namespace
     * @param string $name
     * @param string $value
     */
    public function append_new_element_ns_cdata(DOMNode &$parentnode, $namespace, $name, $value = null) {
        $newnode = $this->doc->createElementNS($namespace, $name);
        if (!is_null($value)) {
            $cdata = $this->doc->createCDATASection($value);
            $newnode->appendChild($cdata);
        }
        return $parentnode->appendChild($newnode);
    }

    /**
     *
     * Adds new node
     * @param DOMNode $parentnode
     * @param string $name
     * @param string $value
     * @return DOMNode
     */
    public function append_new_element(DOMNode &$parentnode, $name, $value = null) {
        $newnode = null;
        if (is_null($value)) {
            $newnode = $this->doc->createElement($name);
        } else {
            $newnode = $this->doc->createElement($name, $value);
        }
        return $parentnode->appendChild($newnode);
    }

    /**
     *
     * Adds new attribute
     * @param DOMNode $node
     * @param string $name
     * @param string $value
     * @return DOMNode
     */
    public function append_new_attribute(DOMNode &$node, $name, $value = null) {
        return $node->appendChild($this->create_attribute($name, $value));
    }

    /**
     *
     * Adds new attribute
     * @param DOMNode $node
     * @param string $namespace
     * @param string $name
     * @param string $value
     * @return DOMNode
     */
    public function append_new_attribute_ns(DOMNode &$node, $namespace, $name, $value = null) {
        return $node->appendChild($this->create_attribute_ns($namespace, $name, $value));
    }

    public function fileName() {
        return $this->filename;
    }

    public function filePath() {
        return $this->filepath;
    }

    protected function on_load() {
        return $this->isloaded;
    }

    protected function on_save() {
        return true;
    }

    protected function on_create() {
        return true;
    }

    public function resetXpath() {
        $this->dxpath = null;
        $this->chkxpath();
    }

    private function chkxpath() {
        if (!isset($this->dxpath) || is_null($this->dxpath)) {
            $this->dxpath = new DOMXPath($this->doc);
            foreach ($this->arrayPrefixNS as $nskey => $nsuri) {
                $this->dxpath->registerNamespace($nskey, $nsuri);
            }
        }
    }

    protected function processPath() {
        $path_parts     = pathinfo($this->filename);
        $this->filepath = array_key_exists('dirname', $path_parts) ? $path_parts['dirname']."/" : '';
    }
}