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

// Primitive "preprocessor" protection

if ($have_category_xref_php3 == "") {
  $have_category_xref_php3 = 1;

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

  class CategoryXref extends Mysql {
    var $data;

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

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

    // Is this instance valid?

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

    // Access to member variables

    function getID() { return $this->data["id"]; }
    function setID($i) { $this->data["id"] = $i; }
    function setCategoryID($v) { $this->data["cat_id"] = $v; }
    function getCategoryID() { return $this->data["cat_id"]; }
    function setQuestionID($v) { $this->data["question_id"] = $v; }
    function getQuestionID() { return $this->data["question_id"]; }
    function setRank($v) { $this->data["rank"] = $v; }
    function getRank() { return $this->data["rank"]; }
    function setLastModDate($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 category (only if the category does not already exist)

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

      // Ensure that this one doesn't already exist

      if ($this->getID() != "") {
	$q = "SELECT * FROM $catXrefTable 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 $catXrefTable VALUES (1, NULL, " .
	$this->getCategoryID() . ", " .
	$this->getQuestionID() . ", " .
	$this->getRank() . ", '" .
	$this->getLastModDate() . "', '" .
	$this->getLastModUser() . "')";
      $this->do_query($q, 0);

      // Update the global "last updated" date

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

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

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

      // Set the right values

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

      $q = "UPDATE $catXrefTable SET " .
	"cat_id = " . $this->getCategoryID() . ", " .
	"question_id = " . $this->getQuestionID() . ", " .
	"rank = " . $this->getRank() . ", " .
	"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 sort category cross references

  function catxref_sort($a, $b) {
    if ($a->getCategoryID() != $b->getCategoryID())
      return ($a->getCategoryID() < $b->getCategoryID()) ? -1 : 1;
    else if ($a->getRank() != $b->getRank())
      return ($a->getRank() < $b->getRank()) ? -1 : 1;
    else
      return 0;
  }

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

  function doCatXrefQuery($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++) 
	$ret[] = new CategoryXref($quests[$i]->getData());
      usort($ret, catxref_sort);
    } else
      $ret[] = new CategoryXref("");

    return $ret;
  }

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

  function getAllCatXrefs() {
    global $catXrefTable;
    
    return doCatXrefQuery("SELECT * FROM $catXrefTable", 1);
  }

  // Find a category xref by ID number

  function getCatXrefByID($id) {
    global $catXrefTable;
    
    $vers = doCatXrefQuery("SELECT * FROM $catXrefTable WHERE id = $id", 1);
    return $vers[0];
  }

  // Find all category xrefs for a given category ID

  function getCatXrefsByCID($cid) {
    global $catXrefTable;
    
    return doCatXrefQuery("SELECT * FROM $catXrefTable WHERE cat_id = $cid", 1);
  }

  // Delete a category xref by ID number

  function deleteCatXrefByID($id) {
    global $catXrefTable;
     
    $vers = doCatXrefQuery("DELETE FROM $catXrefTable WHERE id = $id", 0);
    return $vers[0];
  }

  // Delete a category xref by category ID number

  function deleteCatXrefByCID($cid) {
    global $catXrefTable;
     
    $vers = docatXrefQuery("DELETE FROM $catXrefTable WHERE cat_id = $cid", 0);

    return $vers[0];
  }

  // Delete a category xref by question ID number

  function deleteCatXrefByQID($qid) {
    global $catXrefTable;
     
    $vers = docatXrefQuery("DELETE FROM $catXrefTable WHERE question_id = $qid", 0);

    return $vers[0];
  }
}