Sindbad~EG File Manager

<?php 
 
 // Shows the grades for a given class in a table with rows labeled by secretNumber and columns by assignment.
 // 9.10.10, added code to process late submissions.
 
require_once('DB.php');
require_once('../queryWebGrades.php');
 
$ClassName = $_POST['ClassName'];
$Teacher = $_POST['Teacher'];
$School = $_POST['School'];
$StartDate = $_POST['StartDate'];
$AssignmentNumber= $_POST['AssignmentNumber'];
$AssignmentFile = $_POST['AssignmentFile'];
$Email = $_POST['Email'];
$SecretNumber = $_POST['SecretNumber'];

function dumpTable($table)
{ 

		$sql = "SELECT * FROM `$table`";
		$result = QueryWebGrades($sql);
		echo "<table border = \"2\">";
		while($r=$result->fetchRow())
		   { echo "<tr>"; foreach($r as $item) { echo "<td> $item </td>";} echo "</tr>"; }
		echo "</table>";
}
 
/*__________________________________________________*/			 
function getStudentNumber($SecretNumber)
// the secret number is congruent to 17 mod 23
// but student numbers auto-increment from 0
// Do not change this scheme as it is built into WebGrades.php
{   return (int) ($SecretNumber / 23);
}
/*__________________________________________________*/			
function getSecretNumber($StudentNumber)
{  return 23 * $StudentNumber + 17;
}
/*____________________________________________________*/
function validEmail($email)
// return true if it's a legal email address, false if not 
{ return eregi("^[_a-z0-9-]+(\.[_a-z0-9-]+)*@[a-z0-9-]+(\.[a-z0-9-]+)*(\.[a-z]{2,3})$", $email);
}
/*__________________________________________________*/			    
function getCourseID(  $ClassName, $Teacher, $School, $StartDate )  
{  
  $sql = "SELECT * FROM `Classes` WHERE ClassName='$ClassName' AND Teacher='$Teacher' AND School='$School' AND StartDate='$StartDate';";
  $r = QueryWebGrades($sql);
  $found = false;
  $row = $r->fetchRow();
  if($row==NULL)
      { return "Class not found.  Check the data specified in the web page that contained the form you submitted";
	  }
  else 
      return $row[0];
}
/*__________________________________________________*/
function displaySecretNumbers()
// for professor's use in setting up his or her spreadsheet
{
 $sql = "SELECT * FROM `Students`";
   $result = QueryWebGrades($sql);
   echo "<table border=\"2\">";
   while($r = $result->fetchRow())
      { $StudentNumber = $r[0];
	    $Email = $r[1];
		$FirstName = $r[2];
		$LastName = $r[3];
		$SecretNumber = getSecretNumber($StudentNumber);
		echo "<tr><td>$SecretNumber</td><td>$LastName, </td><td>$FirstName  </td><td>$Email</td></tr>";
	   }
   echo "</table>";
}
 
/*__________________________________________________*/					        
   
function dumpRawGrades($SecretNumber)
// display all the submissions of one student
{ $StudentNumber = getStudentNumber($SecretNumber);
  $sql = "SELECT * FROM `Homework` WHERE StudentNumber='$StudentNumber' ORDER BY SubmissionDate";
  $r = QueryWebGrades($sql);
  while( $row = $r->fetchRow())
     { foreach($row as $item)
          { echo "$item ";
          }
	   echo "<br>";
     }
}	

/*__________________________________________________*/
function oldTopic($topic)
// Return the MathXpert32 topic number corresponding to the MathXpert64 topic number $topic
{ if($topic < 155)
     return $topic + 5;
  return $topic + 6;
}

/*__________________________________________________*/
function newTopic($topic)
// Return the MathXpert64 topic number corresponding to the MathXpert32 topic number $topic
{ if($topic < 160)
     return $topic - 5;
  return $topic - 6;
}


/*__________________________________________________*/			
function getProblemNumbers( $ClassName, $Teacher, $School, $StartDate, $AssignmentFile, $AssignmentNumber)
// return an array $problemNumbers.  $problemNumbers[$TopicOrFilename] is an array of the assigned problem numbers on that topic in the specified assignment.
 
{ $CourseID = getCourseID($ClassName, $Teacher, $School, $StartDate); 
  $L = file($AssignmentFile);  // read the assignment file into an array of lines
  $found = false;
  $ans  = array();
  foreach ($L as $line)
      { $line = trim($line); 
	    if(substr($line,0,2)=="//") continue;   // a comment-only line
		if($line == "") continue;    // a blank line
	    $line = split("//", $line);
		$line = trim($line[0]);    // discard comments and initial white space
	    // is this a line starting a new assignment?
	    $start = substr($line,0,3);
		if($start == "Ass")
		    { // yes, it does start a new assignment
			   if($found) 
			      return $ans;
			   $p = explode(":", $line);
			   $p1 = preg_split("/[\s]+/",trim($p[0]));   // allowing multiple spaces as in "Assignment    5"
		       $AssignmentNumber2 = trim($p1[1]);  // it will be a number if the assignment file is correctly formatted.
		       if($AssignmentNumber2 == $AssignmentNumber)   
			        $found = true; // this is not the desired assignment
		    }
	    if(!$found) 
		    continue;
		// now read the next line of the assignment
		$p = explode(":",$line);
		$q = $p[1]; 
		$TopicOrFilename = trim($p[0]);
		// now put the problem numbers specified in $q into this array

		$y = split("-",$q);
		$J = 0;
		$next = array();
		if(count($y) == 2 && is_numeric($y[0]) && is_numeric($y[1]))  // as in 1-12
		    { for($k=$y[0]; $k <= $y[1]; $k++)
			    { $next[$J] = $k;
				  $J++;
				}
		    }
	    $ans[$TopicOrFilename] = $next;
	  }
	return $ans;  // we get here if the last assignment was the one specified
}
 
/*________________________________________________*/	
		 
 
?>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Homework Grades</title>
</head>

<body>
<?php 
  
$stop = false;
$ProblemNumbers = getProblemNumbers($ClassName, $Teacher,$School, $StartDate, $AssignmentFile, $AssignmentNumber);
$Email = trim($Email);
$SecretNumber = trim($SecretNumber);
// sanitize $Email and $SecretNumber to prevent an attacker from entering code fragments into those text fields
if($Email != "")
   { if(strlen($Email) > 64)
        { $stop = true;
		  echo "That email address is too long.  It should not exceed 64 characters.<br>";
		}
	 else if(!validEmail($Email))
	    {  $stop = true;
		   echo "Invalid email address.<br>";
	    }
	 else
        { $sql = "SELECT * FROM Students WHERE Email='$Email';";
	    }
   }
else if($SecretNumber != "")
   { if(strlen($SecretNumber) > 24)
         { $stop = true;  
		   echo "Secret Number is too long.<br>";
		 }
      else if(!is_numeric($SecretNumber))
	     { echo "Your secret number should be a number.<br>";
		   $stop =true;
		 } 
      else if($SecretNumber % 23 != 17)
	     { $stop = true;
		   echo "That secret number is invalid.<br>";
		 }
     else 
	     { $StudentNumber = getStudentNumber($SecretNumber);  
           $sql = "SELECT * FROM Students WHERE StudentNumber='$StudentNumber';";
		 }
   }
else 
   { echo "Enter the email address you used to register for WebGrades, or your secret number.<br>";
     $stop = true;
   }
   
if(!$stop)
     echo "<p> The following table shows your submissions for Assignment $AssignmentNumber.  If you don't see the submissions you were expecting, a possible cause is that you submitted some different problems that were not on this assignment. </p>";
if(!$stop)
  { $q = QueryWebGrades($sql);
    $r = $q->fetchRow();
    if(!isset($r[0]))
       { echo "Cannot find you in the database.  Enter the email address you used to register for WebGrades, or your secret number.<br>";
	   }
    else
       { $StudentNumber = $r[0];
	     echo "<table border=\"2\">";
	     echo "<hr> <td>Problem Number</td> <td>Submission Date</td> </hr>";
	     $sql = "SELECT * FROM `Homework` WHERE StudentNumber='$StudentNumber' ORDER BY SubmissionDate";
         $r = QueryWebGrades($sql);
         while( $row = $r->fetchRow())
            { $Topic =  $row[1];
		      $Filename = $row[2];
		      if($Filename!= "")
		         { $Topic = newTopic($Topic);
		         }
	   	      $ProblemNumber = $row[3];
		      $SubmissionDate = $row[4];
		      $problems = $ProblemNumbers[$Topic];
		      $problems2 = $ProblemNumbers[$Filename];
		      if((is_array($problems) && in_array($ProblemNumber,$problems)) || (is_array($problems2) && in_array($ProblemNumber, $problems2)))
		          { echo "<tr> <td>$ProblemNumber</td><td>$SubmissionDate</td>";
			      }
			 
		    }
	      echo "</table>";
        }
   }  
?>

 
  
</body>
</html>