<?php
/****************************************************************************************************************************************************
 *
 *
 *	PHP ENTREZ TOOLS
 *	~~~~~~~~~~~~~~~~~~
 *	- v0.1 - last changed 2008-10-15 by joe@cotch.net
 *	- eSummary: http://www.ncbi.nlm.nih.gov/entrez/query/static/esummary_help.html
 *
 *	License
 *	~~~~~~~
 *   		This file is part of PHP Entrez Tools (PET)
 *
 *    		PET is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by
 *    		the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 *
 *    		PET is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
 *
 *    		You should have received a copy of the GNU General Public License along with PET.  If not, see <http://www.gnu.org/licenses/>.
 *
 *
 ***************************************************************************************************************************************************/
 
require_once("Variables.php");
require_once("HttpRequest.php");
require_once("XmlArray.php");


class eSummary
{
	var $DB;
	var $QueryKey;		// int - entrez's session query number
	var $WebEnv;		// string - entrez's session ID 
	var $IdList;		// array  - if you're not using sessions, you'll need to feed in a list of IDs -- this only works if WebEnv is not set
	var $RetStart;
	var $RetMax;
	
	var $QueryData;
	
	var $Identifier;	// string - used in place of QueryKey for the cache name as a more perminent form of identification, e.g. a pubmed QueryTranslation
	var $CacheName;
	
	var $Xml;
	var $Html;
	var $Error;
	
	function eSummary( $DB = 'pubmed', $QueryKey = null, $WebEnv = null, $RetStart = 0, $RetMax = null )
	{
		Global $ncbi_RetMax;
		
		$this->DB = $DB;
		if (isset($QueryKey)) $this->QueryKey = $QueryKey;
		if (isset($WebEnv))   $this->WebEnv   = $WebEnv;
		if (isset($RetStart)) $this->RetStart = $RetStart;
		if (isset($RetMax))   $this->RetMax   = $RetMax;
		else $this->RetMax = $ncbi_RetMax;
	}
	
	function Run( $Level = 0 )
	{
		if (empty($this->CacheName)) $this->MakeCacheName();
		if (empty($this->QueryData)) $this->MakeQueryData();
		$this->GetXmlFile();
		if ($Level >= 1) {
			$this->MakeArray();
			if (empty($this->Array)) throw new Exception( "Failed to create an Array from the XML in eSearch->Run->MakeArray calling to XmlArray->eSearch." );
			if ($this->CheckArray() == false) throw new Exception( $this->Array['ERROR'] );
		}
		return true;
	}
	
	function MakeCacheName()
	{
		Global $ncbi_CachePath;
		$this->DB = str_replace("/", "", $this->DB); 	// escape slashes in the DB name for the unlikely event that this is used for filesystem attacks      
		$dir = $ncbi_CachePath . $this->DB;					// Make database specific folders
		if (!file_exists($dir)) mkdir($dir);
		$dir .= "/eSummary";
		if (!file_exists($dir)) mkdir($dir);
		
		// Create a file name -- this will be md5 scrambled because otherwise we might end up with excessive file name lengths through using QueryTranslations
		if (isset($this->Identifier)) $fn = array($this->RetStart, $this->RetMax, $this->Identifier);
		else $fn = array($this->RetStart, $this->RetMax, $this->WebEnv);
		$fn = implode("--", $fn);
		$fn = md5($fn);
		
		$dir .= "/" . substr($fn, 0, 1);			// Add the first letter of the search term to the folder to prevent dirs getting too big
		if (!file_exists($dir)) mkdir($dir);
				
		$this->CacheName = $dir . "/" . $fn . ".txt";
	}

	function MakeQueryData()
	{
		$this->QueryData = array(
    			"db"		=> "pubmed",
    			"usehistory" 	=> "y",
    		);
    		if (isset($this->DB)) 	    $this->QueryData['db'] 	  = $this->DB;
    		if (isset($this->WebEnv))   $this->QueryData['WebEnv']    = $this->WebEnv;
     		if (isset($this->QueryKey)) $this->QueryData['query_key'] = $this->QueryKey;
    		if (isset($this->RetStart)) $this->QueryData['retstart']  = $this->RetStart;
    		if (isset($this->RetMax))   $this->QueryData['retmax']    = $this->RetMax;
		if (isset($this->IdList) and empty($this->WebEnv)) $this->QueryData['id'] = implode(",", $this->IdList);
	}

	function GetXmlFile()
	{
		try { $Request = new EntrezRequest( "eSummary", $this->CacheName, $this->QueryData ); }
		catch (Exception $e) { throw new Exception($e->getMessage()); }					// Pass on any errors
		if (!empty($Request->Html)) $this->Html .= $Request->Html;					// Pass on any HTML messages
		if (empty($Request->Xml)) { throw new Exception( "Empty XML file." ); }
		$this->Xml = $Request->Xml;
		unset($Request);
	}

	function MakeArray()
	{
		if (empty($this->Xml)) return false;
		require_once("XmlArray.php");
		$Arr = new XmlArray($this->Xml);
		$this->Array = $Arr->Array;
		unset($Arr);
		return $this->Array;
	}
	
	function CheckArray()
	{
		if (isset($this->Array['ERROR'])) { $this->DeleteCache(); return false; }
		return true;
	}
	
	function DeleteCache()
	{
		if (empty($this->CacheName)) $this->MakeCacheName();
		if (file_exists($this->CacheName)) { unlink($this->CacheName); return true; }
		else return false;
	}

}

?>