<? // -*- c++ -*-

// Primitive "preprocessor" protection

if ($have_version_xref_php3 == "") {
  $have_version_xref_php3 = 1;

  if ($maintdir == "") $maintdir = "..";
 
  require("$maintdir/constants.php3");
  require("$classdir/MySQL.php");
  require("$verdir/constants.php3");
  require("$classdir/System.php3");

  class VersionXref extends Mysql {
    var $data;

    // Constructor
    
    function VersionXref($data) {
      global $faqDB;

      $this->Mysql($faqDB);
      $this->data = $data;
    }

    // Is this instance valid?

    function isValid() {
      if ($this->data["version_id"] <> "" &&
	  $this->data["question_id"] <> "" &&
	  $this->data["andup"] <> "") {
	return true;
      } else {
	return false;
      }
    }

    // Access to member variables

    function getID() { return $this->data["id"]; }
    function setVersionID($v) { $this->data["version_id"] = $v; }
    function getVersionID() { return $this->data["version_id"]; }
    function setQuestionID($v) { $this->data["question_id"] = $v; }
    function getQuestionID() { return $this->data["question_id"]; }
    function setAndUp($v) { $this->data["andup"] = $v; }
    function getAndUp() { return $this->data["andup"]; }
    function setLastModDate($d) { $this->data["last_mod_date"] = $d; }
    function getLastModDate() { return $this->data["last_mod_date"]; }
    function setLastModUser($u) { $this->data["last_mod_user"] = $u; }
    function getLastModUser() { return $this->data["last_mod_user"]; }

    // Create a version (only if the version does not already exist)

    function create() {
      global $theUser;
      global $verXrefTable;
      if (!$this->isValid())
	return;

      // Ensure that this one doesn't already exist

      if ($this->getID() != "") {
	$q = "SELECT * FROM $verXrefTable WHERE id = " . 
	  $this->getID(); 
	$foo = $this->do_query($q, 1);
	if ($foo[0]->isValid())
	  return;
      }

      $this->setLastModDate(date("Y-m-d"));
      $this->setLastModUser($theUser->getID());

      $q = "INSERT INTO $verXrefTable VALUES (1, NULL, " .
	$this->getVersionID() . ", " .
	$this->getQuestionID() . ", " .
	$this->getAndUp() . ", '" .
	$this->getLastModDate() . "', '" .
	$this->getLastModUser() . "')";
      $this->do_query($q, 0);

      // Update the global "last updated" date

      $sys = new System();
      $sys->update();
    }

    // Update a version (only if the version already exists)

    function update() {
      global $theUser;
      global $verTable;
      if (!$this->isValid())
	return;

      // Set the right values

      $this->setLastModDate(date("Y-m-d"));
      $this->setLastModUser($theUser->getID());

      $q = "UPDATE $verTable SET " .
	"version_id = " . $this->getVersionID() . ", " .
	"question_id = " . $this->getQuestionID() . ", " .
	"andup = " . $this->getAndUp() . ", '" .
	"last_mod_date = '" . $this->getLastModDate() . "', " .
	"last_mod_user = '" . $this->getLastModUser() . "' " .
	"WHERE id = " . $this->getID();
      $this->do_query($q, 0);

      // Update the global "last updated" date

      $sys = new System();
      $sys->update();
    }
  }

  // Function to do a generic query and return an array of VersionXrefs

  function doVerXrefQuery($q, $want_rows) {
    global $faqDB;

    $m = new Mysql($faqDB);
    $quests = $m->do_query($q, $want_rows);
    if ($want_rows && $quests[0]->isValid())
      for ($i = 0; $i < sizeof($quests); $i++)
	$ret[] = new VersionXref($quests[$i]->getData());
    else
      $ret[] = new VersionXref("");

    return $ret;
  }

  // Function to return an array of all version xrefs in objects

  function getAllVerXrefs() {
    global $verXrefTable;
    
    return doVerXrefQuery("SELECT * FROM $verXrefTable", 1);
  }

  // Find a version xref by ID number

  function getVerXrefByID($id) {
    global $verXrefTable;
    
    $vers = doVerXrefQuery("SELECT * FROM $verXrefTable WHERE id = $id", 1);
    return $vers[0];
  }

  // Find all version xrefs for a given question ID

  function getVerXrefsByQID($qid) {
    global $verXrefTable;
    
    $vers = doVerXrefQuery("SELECT * FROM $verXrefTable WHERE question_id = $qid", 1);
    return $vers;
  }

  // Delete a version xref by ID number

  function deleteVerXrefByID($id) {
    global $verXrefTable;
     
    $vers = doVerXrefQuery("DELETE FROM $verXrefTable WHERE id = $id", 0);
    return $vers[0];
  }

  // Delete a version xref by question ID number

  function deleteVerXrefByQID($qid) {
    global $verXrefTable;
     
    $vers = doVerXrefQuery("DELETE FROM $verXrefTable WHERE question_id = $qid", 0);
    return $vers[0];
  }
}