<?php
/**
 * @class CDAWEB 
 * @brief  CDAWeb 
 * @details
 */
class CDAWEB extends RemoteDataCenterClass
{

	private $dataViewURL = NULL;

	private $ch; 

	private $obsGroupsIds;

	private $spase_res, $insXML, $xp = null;

	
	private $observatoryGroups, $instrumentTypes;
	private $CDAWEB = array(), $masterCDF = array();

	private $header;

	
	// https://cdaweb.gsfc.nasa.gov/WS/cdasr/1/dataviews/sp_phys/instrumentTypes

	private $validInstrumentTypes = [ "Activity%20Indices", "Electric%20Fields%20(space)","Gamma%20and%20X-Rays",

                                     "Magnetic%20Fields%20(space)", "Particles%20(space)", "Plasma%20and%20Solar%20Wind", 

                                     "Radio%20and%20Plasma%20Waves%20(space)"]; //, "Ephemeris/Attitude/Ancillary" ];  

	private $excludeIns = ["GIFWALK", "Unknown"], $excludeGroup = ["THEMIS", "ARTEMIS", "MMS", "Apollo"]; // "NOAA", "GPS", "TSS-1R", "IBEX"];

	
	// not in "https://heliophysicsdata.sci.gsfc.nasa.gov/queries/CDAWeb_SPASE.xql" List;
	// FOR INFO : Excluded automatically

    private $excludeDatasets = [ "DMSP_R0_SSJ4", "DMSP_R0_SSIES", "I7_R0_LEPEDEA", "I8_R0_LEPEDEA" ];

	protected $DDserverXml, $DDserverXmlName;

	
	public function html_encode($param) 
	{
		$pairs = array(" " => "%20"); 
		
		return strtr($param,$pairs); 
	}
	

	public function html_decode($param) 
	{
		$pairs = array("%20" => " "); 
		
		return strtr($param,$pairs); 
	}
	

	public function init() 	

	{			

		error_log("CDAWEB Proxy creation on ".date("Y-m-d\TH:i:s").PHP_EOL,3,log);
		error_log("CDAWEB Proxy creation on ".date("Y-m-d\TH:i:s").PHP_EOL,3,err);

		
        error_reporting(ALL);
        

		$this->initStreamContext();

		$this->getAllSpaseDatasets();
		
		// predefined samplings
		if (file_exists(RemoteData."/samplingCDAWEB.xml")) {
            $samplingsDom = new DomDocument("1.0");
            if ($samplingsDom->load(RemoteData."/samplingCDAWEB.xml")) {
                $this->xp = new domxpath($samplingsDom);
            }
		}
	} 

	private function openConnection() 
	{	

		$this->ch = curl_init();			 
		curl_setopt($this->ch, CURLOPT_RETURNTRANSFER, 1);

		curl_setopt($this->ch, CURLOPT_TIMEOUT, 600);

		// Add proxy definition
		$PROXY_HOST=getenv('PROXY_HOST');
		$PROXY_USERPWD=getenv('PROXY_USERPWD');
		if (!empty($PROXY_HOST)) {
			curl_setopt($this->ch, CURLOPT_PROXY, getenv('PROXY_HOST'));
			if (!empty($PROXY_USERPWD)) {
				curl_setopt($this->ch, CURLOPT_PROXYUSERPWD, getenv('PROXY_USERPWD'));
			}
		}

	} 
		  
	private function closeConnection()
	{
		curl_close($this->ch);	
	}

	private function initStreamContext()
	{

		$context = array(
			'http' => array(
				'timeout' => 600,
			),
		);

		$PROXY_HOST=getenv('PROXY_HOST');
		$PROXY_USERPWD=getenv('PROXY_USERPWD');
		if (!empty($PROXY_HOST)) {

			$context['http']['proxy'] = "tcp://$PROXY_HOST";
			$context['http']['request_fulluri'] = TRUE;

			if (!empty($PROXY_USERPWD)) {
				$context['http']['header'] = "Proxy-Authorization: Basic ".base64_encode($PROXY_USERPWD);
                        }

		}

		stream_context_set_default($context);

	}

	/**
	* Using CDAS REST APIs get ALL CDAWEB dataset descriptions
	* Create an array obsGroupsIds[$obsGroupId][$obsId][$insId][$dsId]
	*/

	protected function getRemoteTree()	

	{
        $this->openConnection();

        $this->obsGroupsIds = array();   

	$dom = NULL;
	$reuse_cache_file = FALSE;
	if (file_exists($this->location."/datasets.xml")) {
		if (time() - filemtime($this->location."/datasets.xml") < 86400) {
			$dom = new DOMDocument();
			if ($dom->load($this->location."/datasets.xml")) {
				echo "Re-use cache file ".$this->location."/datasets.xml".PHP_EOL;
				$reuse_cache_file = TRUE;
			}
		}
	}

	if (!$reuse_cache_file) {
		$dom = $this->loadFromCDAWebWS("datasets", array());
		if (!$dom) {
			error_log('Cannot retrieve CDAWeb datasets list');
			return;
		}
		$dom->save($this->location."/datasets.xml");
	}

        $datasets = $dom->getElementsByTagName("DatasetDescription");

    
        echo "All CDAWeb datasets : ".$datasets->length.PHP_EOL;

        foreach ($datasets as $ds) {
        
            $insType = $ds->getElementsByTagName("InstrumentType")->item(0)->nodeValue;
            
            if (in_array ($this->html_encode($insType), $this->validInstrumentTypes )) {

                $id = $ds->getElementsByTagName("Id")->item(0)->nodeValue;
                            
                $insId = $ds->getElementsByTagName("Instrument")->item(0)->nodeValue;
                if (! in_array ($insId, $this->excludeIns )) {
                    $obsId = "UNKNOWN";
                    if ($ds->getElementsByTagName("Observatory")->length > 0)  
                        $obsId = $ds->getElementsByTagName("Observatory")->item(0)->nodeValue;
                        
                    $obsGroupId = "UNKNOWN"; 
                    if ($ds->getElementsByTagName("ObservatoryGroup")->length > 0)
                        $obsGroupId = $ds->getElementsByTagName("ObservatoryGroup")->item(0)->nodeValue;
                    
                    if ($obsId == "UNKNOWN") {
                         $obsId = $obsGroupId;
                    }  
                    
                    if ( $obsGroupId == "UNKNOWN" ) {
                        $obsGroupId = $obsId;
                    }  
                    
                    if ( $obsGroupId != "UNKNOWN" ) {
                        $this->obsGroupsIds[$obsGroupId][$obsId][$insId][]  = $id;  
                    }
            }
        }
        }

	}

	 
	protected function createObservatoryNode($id, $grpId) 
	{

		$obsNode = $this->domAmda->createElement('observatory');

		$obsNode->setAttribute("xml:id",$this->baseID.":".$this->param2dd($grpId).":".$this->param2dd($id));
		$obsNode->setAttribute("name",$id);

		return $obsNode;

	}
	

	protected function createInstrumentNode($id, $obsId, $groupId) 
	{

		$insNode = $this->domAmda->createElement('instrument');
				
		$insNode->setAttribute("xml:id",$this->baseID.":".$this->param2dd($groupId).":".$this->param2dd($obsId).":".$id);
		$insNode->setAttribute("name",$id);
	  //	$insNode->setAttribute("description",$ins[1]);
		
		return $insNode;
	}
	
	protected function createDatasetNode($dsId)
	{		

		if ( !array_key_exists($dsId, $this->CDAWEB ))
			return null; // no description in SpaseRegistry => we do not add this dataset

		$dsNode = $this->domAmda->createElement('dataset');

		$obj = $this->loadFromCDAWebWS("datasets", array("idPattern" => $dsId), TRUE);
		if (!$obj) {
			return NULL;
		}

		$dataSet = $obj->DatasetDescription;

      
		$dsNode->setAttribute("xml:id",$this->baseID.":".$dsId);
		$dsNode->setAttribute("name", $dsId);
		$startTime = $dataSet[0]->TimeInterval->Start;
		$endTime =  $dataSet[0]->TimeInterval->End;
		$label = $dataSet[0]->Label; 
		$url = $dataSet[0]->DatasetLink[0]->Url;
		$notesUrl = $dataSet[0]->Notes; 
		$piAffilation = $dataSet[0]->PiAffiliation;
		$piName = $dataSet[0]->PiName; 
		$sampling = $this->getDatasetSpaseDescription($dsId);
		$this->updateDDServerXml("GlobalStart",$startTime);
		$this->updateDDServerXml("GlobalStop",$endTime);

		// no SPASE description
		if ($sampling == -1) return null;
		

		if ($sampling <= 0)	{
            // check if there is file with predefined samplings

            if ($this->xp) {
                $set = $this->xp->query("//dataset[@xml:id='".$dsId."']");
                if ($set->length > 0) {
                    $sampling = $set->item(0)->nodeValue;
                    echo "from samplingCDAWEB : ".$dsId." : ".$sampling.PHP_EOL;
                    $this->updateDDServerXml("MinSampling",$sampling);	
                }  else {                    

                    echo " No sampling : ".$dsId.PHP_EOL;

                    error_log("! No sampling and No dataset in samplingCDAWEB defined : ".$dsId." : ".$sampling.PHP_EOL,3,err);
                }
            } else {
                echo " No xpath ".PHP_EOL;
                error_log("! No sampling and No xpath defined : ".$dsId." : ".$sampling.PHP_EOL,3,err);
            }
			
		}

        else 

			$this->updateDDServerXml("MinSampling",$sampling);	

		$dsNode->setAttribute('spaseUrl',$this->CDAWEB[$dsId]);

	//   $dsNode->setAttribute('masterCdf',$this->existsMasterCdf($dsId));

		$dsNode->setAttribute("desc", "$label; $startTime - $endTime");

		$dsNode->setAttribute("dataStart", $startTime); 
		$dsNode->setAttribute("dataStop", $endTime); 

		$parameterNodes = $this->createParameterNodes($dsId);

		foreach ($parameterNodes as $parameterNode)

		{
			$dsNode->appendChild($parameterNode);
		}
		
		return $dsNode;
	}
	
	protected function createParameterNodes($dsId)
	{	

	 	$obj = $this->loadFromCDAWebWS("datasets/".$dsId."/variables", array(), TRUE);
		if (!$obj)
			return array();

	 	$parameters = $obj->VariableDescription;

		$paramNodes = array();

		foreach ($parameters as $param)
		{
			$paramNode = $this->domAmda->createElement('parameter');
			$paramNode->setAttribute("xml:id", $this->baseID.":".$dsId.":".$param->Name);
			$paramNode->setAttribute("name", $param->Name);
			
			$paramNodes[] = $paramNode;
		}	
		
		return $paramNodes;
	}
	
	protected function getDatasetSpaseDescription($dsID)

	{		 

		if ( !array_key_exists($dsID, $this->CDAWEB ))
			return -1; // no description in SpaseRegistry

		
		if (!$this->loadSpaseResource($this->CDAWEB[$dsID], $this->spase_res)) return -100;
	

		$messages = $this->spase_res->getElementsByTagName('Message');

		
		if ($messages->length > 0)
		{

    // 		foreach ($messages as $message)
    // 					echo $message->nodeValue.PHP_EOL;

			return -2;   // no description in  www-spase
		}
		

//  		$instrument = $this->spase_res->getElementsByTagName('InstrumentID');
//         echo "  SPASE :   instrument ".$instrument->item(0)->nodeValue.PHP_EOL;

		$cadence = $this->spase_res->getElementsByTagName('Cadence');

		if ($cadence->length == 0)

			return -3; // no cadence in spase xml
			
		$sampling = $this->cadence2sampling($cadence->item(0)->nodeValue);
		
		return $sampling; 	 
	}
	
	public function cadence2sampling($cadence)
	{
		$scale = array('S' => 1, 'M' => 60, 'H' => '3600');

		$value = substr($cadence,2,strlen($cadence)-3);

		$units = substr($cadence,-1); 

		$sampling = floatval($value)*$scale[$units];
		

		return $sampling;
	}
	

	/**
	* Get IDs and SPASE URLs of all CDAWEB SPASE-defined datasets ( SPASEql )
	* Create an array $CDAWEB[$ID] = SpaseID
	*/

	protected function getAllSpaseDatasets()
	{

		$this->initStreamContext();

		require_once "simple_html_dom.php";

		if (file_exists($this->location."/NumericalData.html"))
			rename($this->location."/NumericalData.html",$this->location."/NumericalData.html.bak");

		// if cannot reach CDAWEB Spase Registry use an old file

		if (!copy(CDAWebConfigClass::$spaseRegistry, $this->location."/NumericalData.html")) {
				error_log('ERROR');

				copy($this->location."/NumericalData.html.bak", $this->location."/NumericalData.html");

		}

		$doc = new DOMDocument('1.0', 'utf-8');
		if (!$doc->loadHTMLFile($this->location.'/NumericalData.html')) {
			error_log("Cannot load ".$this->location.'/NumericalData.html');
		}

		$xpath = new DOMXPath($doc);
		$ids = $xpath->query("//td[@class='Spase.URL.ProductID']");

		foreach ($ids as $id)

		{
			$key = $id->nodeValue;
			$spase = $id->nextSibling->nodeValue;
			if (!empty($key) && (strlen($spase) > 25)) {
				$this->CDAWEB[$key] = $spase;
			}

		}

		error_log("SPASE-defined CDAWEB datasets from ".CDAWebConfigClass::$spaseRegistry." : ".count($this->CDAWEB).PHP_EOL,3,log);

		echo "SPASE-defined CDAWEB datasets : ".count($this->CDAWEB).PHP_EOL;

	}
	
	protected function initDDServerXml($ds, $ins, $obs)
	{
		$this->DDserverXml = new DomDocument("1.0");
		$this->DDserverXmlName =  $this->DDserverDir."/".$ds.".xml";
		$rootNode = $this->DDserverXml->createElement('VI');
		$this->DDserverXml->appendChild($rootNode);
		$rootNode->appendChild($this->DDserverXml->createElement("DataBaseID", $this->baseID));
		$rootNode->appendChild($this->DDserverXml->createElement("Mission", $obs));
		$rootNode->appendChild($this->DDserverXml->createElement("Instrument", $ins));
		$rootNode->appendChild($this->DDserverXml->createElement("DataSetID", $ds));
		$rootNode->appendChild($this->DDserverXml->createElement("GlobalStart"));
		$rootNode->appendChild($this->DDserverXml->createElement("GlobalStop"));

		$rootNode->appendChild($this->DDserverXml->createElement("MinSampling"));
		// fill value by default - if different - add into param description

		$rootNode->appendChild($this->DDserverXml->createElement("FillValue", -1.0E31));

	}
	
	protected function updateDDServerXml($target, $value)
	{
		$node = $this->DDserverXml->getElementsByTagName($target);
		$node->item(0)->nodeValue = $value;
	}
	
	protected function saveDDServerXml()
	{
		$this->DDserverXml->save($this->DDserverXmlName);
	}
	
	protected function existsMasterCdf($dsId)
	{

		$this->initStreamContext();

		$file = CDAWebConfigClass::$masterUrl.strtolower($dsId)."_00000000_v01.cdf";
		$file_headers = @get_headers($file);
		
		if(!$file_headers || $file_headers[0] == 'HTTP/1.1 404 Not Found') {
			$exists = false;

			error_log("INFO:   no master CDF ".$dsId.PHP_EOL,3,log);

		}
		else {
			$exists = true;
		}
		
		return $exists;
	}
		 
	protected function getMasterCdf($dsId)
	{

		$this->initStreamContext();

		$file = CDAWebConfigClass::$masterUrl.strtolower($dsId)."_00000000_v01.cdf";
		$file_headers = @get_headers($file);
		
		if(!$file_headers || $file_headers[0] == 'HTTP/1.1 404 Not Found') {
			 return false;
		}		 
		return $file;		 	 
	}
	
	public function getData($ds, $start, $stop)
	{

		$this->initStreamContext();

		$this->openConnection();

		$res = $this->loadFromCDAWebWS("datasets/$ds/orig_data/$start,$stop/", array());
		if (!$res) {
			return array();
		}

		if ($res->getElementsByTagName("html")->length > 0)
		{

			error_log("ERROR no response for : ".$ds." : ".$start." - ".$stop.PHP_EOL,3,err);
			error_log($res->saveXML(),3,err);

			$this->closeConnection();
			return array();

		}

		$fileNames = $res->getElementsByTagName("Name");

	   	   
		$nc_prefix = strlen($ds) > RemoteDataCenterClass::$MAX_VI_NAME_LENGTH ? 
				substr(strtolower($ds),0,RemoteDataCenterClass::$MAX_VI_NAME_LENGTH - 1): strtolower($ds);
		$files = array();
	   
		for ($i = 0; $i < $fileNames->length;  $i++)
	   {
			$fileName = $fileNames->item($i);
			$url = $fileName->nodeValue;
			$file_headers = @get_headers($url);
		
			if(!$file_headers || $file_headers[0] == 'HTTP/1.1 404 Not Found') {

				error_log("ERROR  404 Not Found for : ".$ds." : ".$start." - ".$stop.PHP_EOL,3,err);

				continue;
			}	
			$temp = explode('/',$url);
			$destination = $temp[count($temp)-1];

			if (copy($url, $destination))
			{
				$ncFile = $this->convert2nc($destination);
				if (strlen($ncFile) > RemoteDataCenterClass::$MAX_NAME_LENGTH)
				{
					$ncFileTrue = $nc_prefix."_".time().$i.".nc";
					rename($ncFile, $ncFileTrue);
					$files[] = $ncFileTrue;
				}
				else
				{
					$files[] = $ncFile;
				}
			}
			else
			{

				error_log("ERROR cannot copy files : ".$ds." : ".$start." - ".$stop.PHP_EOL,3,err);

			}
	   }
	   
		$this->closeConnection();
		
		return $files;
	}
	
	protected function convert2nc($file)
	{

		system("cdfnew2nc $file");		 

		$ncFile = str_replace(".cdf", ".nc", $file);
		

 		if (!file_exists($ncFile)) {
			error_log("ERROR while converting ".$file.PHP_EOL,3,err);
			return false; 
 		}

		unlink($file);	
		
		return $ncFile;
	}
	

	public function getDatasetInfo($ds)
	{

		if (!$this->existsMasterCdf($ds)) return false;
		
		$masterCdf = $this->getMasterCdf($ds);

		$localCdf = strtolower($ds).".cdf";

		if (!copy($masterCdf, $localCdf)) return false;

	 
		$infoFile = $this->convert2nc($localCdf);
	  
		return $infoFile;
	}

	
	public function makeProxy()

	{ 

		$this->spase_res = new DomDocument("1.0");
		$this->domAmda = new DOMDocument('1.0', 'utf-8');
		$this->domAmda->formatOutput = TRUE;
		$this->domAmda->preserveWhiteSpace = FALSE;
		
		$dataRoot = $this->domAmda->createElement('dataRoot');
		$dataRoot->setAttribute('xml:id', 'myRemoteData-treeRootNode');
		$this->domAmda->appendChild($dataRoot);	
		
		$this->dataCenter=$this->domAmda->createElement('dataCenter');

	 	$this->setDataCenterAttributes();
	 	

		$dataRoot->appendChild($this->dataCenter);

        foreach ($this->obsGroupsIds as $groupId => $obss)
        {
            if (in_array($groupId, $this->excludeGroup)) continue;
            echo $groupId.PHP_EOL; 
            $obsNodes = array();
            foreach ($obss as $obs => $inss)
            {
                // ! observatory OMNI is taken for observatoriesGroup OMNI only !
                if (substr($obs,0,4) == "OMNI" && substr($groupId,0,4) != "OMNI"){
                    echo 'OMNI      '.$obs.' '.$missionId.PHP_EOL;
                    continue;
                } 
                $insNodes = array();
                // Create instrument nodes
                foreach ($inss as $ins => $dss)
                {
                    $dsNodes = array();
                    // Create datasets nodes
                    foreach ($dss as $ds)
                    {	
                        $dsId = $this->baseID.":".$ds;
                            
                        if (!$this->domAmda->getElementById($dsId)){
                            $this->initDDServerXml($ds,$ins,$obs);
                            $dsNode = $this->createDatasetNode($ds);

                            if ($dsNode){
                                $this->saveDDServerXml();
                                $dsNodes[] = $dsNode;
                            }
                        }	
                    } // foreach ($dss as $ds)
                    
                    if (!empty($dsNodes))
                    {
                            // last $spase_res : instrument should be the same
                            $insSpaseId = $this->getInstrumentSpase();   

                            if (!$insSpaseId || is_array($insSpaseId)) 
                                $insSpaseId = $ins;

                            $obsSpaseId = strtolower($this->getObservatorySpase());
                            if (!$obsSpaseId ) 
                                $obsSpaseId = strtolower($obs);

                            $insId = $this->baseID.":".$this->param2dd($groupId).":".$this->param2dd($obsSpaseId).":".$this->param2dd($insSpaseId);

                            if (!($insNode = $this->domAmda->getElementById($insId))){
                                $insNode = $this->createInstrumentNode($insSpaseId, $obsSpaseId, $groupId);
                            }
                            
                            foreach ($dsNodes as $dsNode){
                                $insNode->appendChild($dsNode);
                            }
                                
                            $insNodes[] = $insNode;
                        }
                    } // foreach ($inss as $ins => $dss)

                    if (!empty($insNodes))
                    {					
                        $obsId = $this->baseID.":".$this->param2dd($groupId).":".$this->param2dd($obsSpaseId);
                        
                        if (!($obsNode = $this->domAmda->getElementById($obsId))){   
                            $obsNode = $this->createObservatoryNode($obsSpaseId, $groupId);
                        }
                        
                        foreach ($insNodes as $insNode){
                            $obsNode->appendChild($insNode);
                        }
                        $obsNodes[] = $obsNode;
                    }
                } // foreach ($obss as $obs => $inss)

                
                if (!empty($obsNodes))
                {
                    $missionId = $this->baseID.":".$this->param2dd($groupId);
                    
                    if (!($missionNode = $this->domAmda->getElementById($missionId))){
                        $missionNode = $this->createMissionNode($groupId);
                    }
                        
                    foreach ($obsNodes as $obsNode)
                    {
                        // observatory == mission
                        if (strtolower($obsNode->getAttribute('name')) == strtolower($missionNode->getAttribute('name'))) {
                            $insNodes = $obsNode->getElementsByTagName("instrument");
                            foreach ($insNodes as $insNode) {
                                $missionNode->appendChild($insNode->cloneNode(true));
                            }
                        }
                        else 
                            $missionNode->appendChild($obsNode);
                    }
                    
                    $this->dataCenter->appendChild($missionNode); 
                }                                
            } 

		$this->closeConnection();

	}
	

	protected function createMissionNode($groupId)
	{

		$missionId = $this->baseID.":".$this->param2dd($groupId);
		$missionNode = $this->domAmda->createElement('mission');
		$missionNode->setAttribute("xml:id",$missionId);
		$missionNode->setAttribute("name",$groupId);
		
		return $missionNode;
	}
	

	protected function getInstrumentSpase()
	{	

		$this->insXML = new DomDocument("1.0");

		if ($this->spase_res){
			$instrument = $this->spase_res->getElementsByTagName('InstrumentID');

			if ($instrument->length > 0) {

                if ($instrument->length == 1) {

		    $this->loadSpaseResource($instrument->item(0)->nodeValue, $this->insXML);

                    return $this->getIdFromSpase($instrument->item(0)->nodeValue);

		}
		else {

                    // $insIds = "";
                    $insIds = array();
                    for  ($i = 0; $i < $instrument->length; $i++ ) {                                            
//                         $insIds  .= $this->getIdFromSpase($instrument->item($i)->nodeValue);
//                         if ($i < $instrument->length - 1) 
//                             $insIds .= "/";
                        $insIds[] = $this->getIdFromSpase($instrument->item($i)->nodeValue);
                    }
                    

		    $this->loadSpaseResource($instrument->item($instrument->length - 1)->nodeValue, $this->insXML);

                    return $insIds;
				}

				//InstrumentType
				//spase://SMWG/Observatory/ACE
			} 
		}	
		
		return null;
	}
	

	protected function getObservatorySpase()
	{

		if ($this->insXML){
			$observatory = $this->insXML->getElementsByTagName('ObservatoryID');
			
			if ($observatory->length > 0) {
				return $this->getIdFromSpase($observatory->item(0)->nodeValue); 			
			} 
		}	
		
		return null;
	}
	

	protected function setDataCenterAttributes(){	
		$this->dataCenter->setAttribute('xml:id', $this->baseID);
	//	$this->dataCenter->setIdAttribute('xml:id', true);
		$this->dataCenter->setAttribute('name', $this->baseID);		
	}
	

	protected function makeArgumentsList(){}

	private function loadSpaseResource($resourceID, &$dom) {
		if (empty($resourceID)) {
			return FALSE;
		}
		$url = str_replace('spase://', 'https://hpde.io/', $resourceID) . '.xml';
		curl_setopt($this->ch, CURLOPT_HTTPHEADER, array("Accept: application/xml"));
		curl_setopt($this->ch, CURLOPT_URL, $url);
                if (!$dom->loadXML(curl_exec($this->ch))) {
			error_log('Cannot load Spase Resource: '.$resourceID);
			return FALSE;
		}
		return TRUE;
	}

	private function loadFromCDAWebWS($api, $params, $asJSON = FALSE) {
		if (!$this->dataViewURL) {
			curl_setopt($this->ch, CURLOPT_URL, CDAWebConfigClass::$restUrl."/dataviews");
			curl_setopt($this->ch, CURLOPT_HTTPHEADER, array("Accept: application/xml"));

			$res = new DomDocument();
			if (!$res->loadXML(curl_exec($this->ch))) {
				return FALSE;
			}

			if ($res->getElementsByTagName('EndpointAddress')->length == 0) {
				error_log("Problem connect to ".CDAWebConfigClass::$restUrl."/dataviews", 3, err);
				return FALSE;
			}

			$this->dataViewURL = $res->getElementsByTagName('EndpointAddress')->item(0)->nodeValue;
		}
		$url = $this->dataViewURL . '/' . $api;
		if (!empty($params)) {
			$params_str = "";
			foreach ($params as $key => $value) {
				if (!empty($params_str)) {
					$params_str .= "&";
				}
				$params_str .= $key."=".urlencode($value);
			}
			$url .= '?'.$params_str;
		}

		if ($asJSON) {
			curl_setopt($this->ch, CURLOPT_HTTPHEADER, array("Accept: application/json"));
		}
		else {
			curl_setopt($this->ch, CURLOPT_HTTPHEADER, array("Accept: application/xml"));
		}
		curl_setopt($this->ch, CURLOPT_URL, $url);

		$res = curl_exec($this->ch);
		if (!$res) {
			return FALSE;
		}

		if ($asJSON) {
			return json_decode($res);
		}

		$dom = new DOMDocument();
     		if (!$dom->loadXML(curl_exec($this->ch))) {
			return FALSE;
		}

		return $dom;
	}

} 
?>