From 2edcfae0afceefceebb3ad332761a588e14819d2 Mon Sep 17 00:00:00 2001
From: Paolo <bison@technikum-wien.at>
Date: Fri, 4 Aug 2017 15:12:36 +0200
Subject: [PATCH] - Added method existsUDF - Added comments

---
 include/udf.class.php | 114 ++++++++++++++++++++++++++++++------------
 1 file changed, 81 insertions(+), 33 deletions(-)

diff --git a/include/udf.class.php b/include/udf.class.php
index cd09f08ae..ce8e4751a 100644
--- a/include/udf.class.php
+++ b/include/udf.class.php
@@ -15,12 +15,15 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
  *
- * Authors: 
+ * Authors: Bison Paolo <bison@technikum-wien.at>
  */
 
 require_once(dirname(__FILE__).'/basis_db.class.php');
 require_once(dirname(__FILE__).'/../config/global.config.inc.php');
 
+/**
+ * Used to export UDF in MS Excel format
+ */
 class UDF extends basis_db
 {
 	/**
@@ -32,7 +35,7 @@ class UDF extends basis_db
 	}
 	
 	/**
-	 * 
+	 * Gets the titles (short description) of the UDF related to the table tbl_person
 	 */
 	public function getTitlesPerson()
 	{
@@ -40,7 +43,7 @@ class UDF extends basis_db
 	}
 	
 	/**
-	 * 
+	 * Gets the titles (short description) of the UDF related to the table tbl_prestudent
 	 */
 	public function getTitlesPrestudent()
 	{
@@ -48,23 +51,67 @@ class UDF extends basis_db
 	}
 	
 	/**
-	 * 
+	 * Loads the UDF definitions related to the table tbl_person
 	 */
 	public function loadPersonJsons()
 	{
-		return $this->_loadJsons('public', 'tbl_person');
+		$jsons = null;
+		
+		if ($this->existsUDF() && $this->prestudentHasUDF())
+		{
+			$jsons = $this->_loadJsons('public', 'tbl_person');
+		}
+		
+		return $jsons;
 	}
 	
 	/**
-	 * 
+	 * Loads the UDF definitions related to the table tbl_prestudent
 	 */
 	public function loadPrestudentJsons()
 	{
-		return $this->_loadJsons('public', 'tbl_prestudent');
+		$jsons = null;
+		
+		if ($this->existsUDF() && $this->prestudentHasUDF())
+		{
+			$jsons = $this->_loadJsons('public', 'tbl_prestudent');
+		}
+		
+		return $jsons;
 	}
 	
 	/**
-	 * 
+	 * Checks if the table system.tbl_udf exists
+	 */
+	public function existsUDF()
+	{
+		$existsUDF = false;
+		
+		$query = 'SELECT COUNT(*) AS count
+					FROM information_schema.columns
+				   WHERE table_schema = \'system\'
+				     AND table_name = \'tbl_udf\'';
+		
+		if (!$this->db_query($query))
+		{
+			$this->errormsg = 'Error!!!';
+		}
+		else
+		{
+			if ($row = $this->db_fetch_object())
+			{
+				if (isset($row->count) && $row->count > 0)
+				{
+					$existsUDF = true;
+				}
+			}
+		}
+		
+		return $existsUDF;
+	}
+	
+	/**
+	 * Checks if the column udf_values exists in table tbl_person
 	 */
 	public function personHasUDF()
 	{
@@ -95,7 +142,7 @@ class UDF extends basis_db
 	}
 	
 	/**
-	 * 
+	 * Checks if the column udf_values exists in table tbl_prestudent
 	 */
 	public function prestudentHasUDF()
 	{
@@ -126,7 +173,7 @@ class UDF extends basis_db
 	}
 	
 	/**
-	 * 
+	 * Loads the UDF definitions related to the given schema and table
 	 */
 	private function _loadJsons($schema, $table)
 	{
@@ -149,11 +196,10 @@ class UDF extends basis_db
 	}
 	
 	/**
-     * 
+     * Sorts the UDF definitions using the proprierty "sort"
      */
     private function _sortJsonSchemas(&$jsonSchemasArray)
     {
-		// 
 		usort($jsonSchemasArray, function ($a, $b) {
 			// 
 			if (!isset($a->sort))
@@ -175,24 +221,23 @@ class UDF extends basis_db
     }
     
     /**
-     * 
+     * Returns an array of associative arrays that contains the couple name and title related to an UDF
+     * These data are retrived from the UDF definitions given as parameter
      */
     private function _getUDFDefinition($jsons)
     {
 		$names = array();
 		
-		// 
 		if ($jsons != null && ($jsonsDecoded = json_decode($jsons)) != null)
 		{
 			if (is_object($jsonsDecoded) || is_array($jsonsDecoded))
 			{
-				// 
 				if (is_object($jsonsDecoded))
 				{
 					$jsonsDecoded = array($jsonsDecoded);
 				}
 				
-				$this->_sortJsonSchemas($jsonsDecoded); // 
+				$this->_sortJsonSchemas($jsonsDecoded);
 				
 				foreach($jsonsDecoded as $udfJsonShema)
 				{
@@ -208,7 +253,7 @@ class UDF extends basis_db
     }
     
     /**
-     * 
+     * Loads UDf titles from phrases
      */
 	private function _loadTitles($udfDefinitions)
 	{
@@ -223,26 +268,29 @@ class UDF extends basis_db
 			if ($i < count($udfDefinitions) - 1) $in .= ', ';
 		}
 		
-		$query = 'SELECT pt.text AS title, p.phrase AS phrase
-						FROM system.tbl_phrase p INNER JOIN system.tbl_phrasentext pt USING(phrase_id)
-					   WHERE pt.sprache = \''.DEFAULT_LEHREINHEIT_SPRACHE.'\'
-						 AND p.phrase IN ('.$in.')';
-			
-		if (!$this->db_query($query))
+		if ($in != '')
 		{
-			$this->errormsg = 'Error occurred while loading jsons';
-		}
-		else
-		{
-			while ($row = $this->db_fetch_assoc())
+			$query = 'SELECT pt.text AS title, p.phrase AS phrase
+							FROM system.tbl_phrase p INNER JOIN system.tbl_phrasentext pt USING(phrase_id)
+						WHERE pt.sprache = \''.DEFAULT_LEHREINHEIT_SPRACHE.'\'
+							AND p.phrase IN ('.$in.')';
+				
+			if (!$this->db_query($query))
 			{
-				for($i = 0; $i < count($udfDefinitions); $i++)
+				$this->errormsg = 'Error occurred while loading jsons';
+			}
+			else
+			{
+				while ($row = $this->db_fetch_assoc())
 				{
-					$udfDefinition = $udfDefinitions[$i];
-					if ($udfDefinition['title'] == $row['phrase'])
+					for($i = 0; $i < count($udfDefinitions); $i++)
 					{
-						$udfDefinition['description'] = $row['title'];
-						$titles[] = $udfDefinition;
+						$udfDefinition = $udfDefinitions[$i];
+						if ($udfDefinition['title'] == $row['phrase'])
+						{
+							$udfDefinition['description'] = $row['title'];
+							$titles[] = $udfDefinition;
+						}
 					}
 				}
 			}