tripal/tripal_cv/includes/tripal_cv.obo_loader.inc

<?php
/**
 * @file
 * Functions to aid in loading ontologies into the chado cv module
 */

/**
 * @defgroup tripal_obo_loader Ontology Loader
 * @ingroup tripal_cv
 * @{
 * Functions to aid in loading ontologies into the chado cv module
 * @}
 */

/**
 * Provides the form to load an already existing controlled
 *  Vocabulary into chado
 *  
 * @param $form
 *   The form array 
 * @param $form_state
 *   The form state array
 *   
 * @return
 *   The form array with new additions
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_form($form, &$form_state) {

  // get a list of db from chado for user to choose
  $sql = "SELECT * FROM {tripal_cv_obo} ORDER BY name";
  $results = db_query($sql);

  $obos = array();
  $obos[] = '';
  foreach ($results as $obo) {
//    $obos[$obo->obo_id] = "$obo->name  | $obo->path";
    $obos[$obo->obo_id] = $obo->name;
  }

  $form['obo_existing'] = array(
    '#type' => 'fieldset',
    '#title' => t('Use a Saved Ontology OBO Reference')
  );

  $form['obo_new'] = array(
    '#type' => 'fieldset',
    '#title' => t('Use a New Ontology OBO Reference')
  );

  $form['obo_existing']['existing_instructions']= array(
    '#value' => t('The Ontology OBO files listed in the drop down below have been automatically added upon
                   installation of the Tripal CV module or were added from a previous upload.  Select
                   an OBO, then click the submit button to load the vocabulary into the database.  If the
                   vocabularies already exist then the ontology will be updated.'),
  );

  $form['obo_existing']['obo_id'] = array(
    '#title' => t('Ontology OBO File Reference'),
    '#type' => 'select',
    '#options' => $obos,
  );

  $form['obo_new']['path_instructions']= array(
    '#value' => t('Provide the name and path for the OBO file.  If the vocabulary OBO file
                   is stored local to the server provide a file name. If the vocabulry is stored remotely,
                   provide a URL.  Only provide a URL or a local file, not both.'),
  );

  $form['obo_new']['obo_name']= array(
    '#type'          => 'textfield',
    '#title'         => t('New Vocabulary Name'),
    '#description'   => t('Please provide a name for this vocabulary.  After upload, this name will appear in the drop down
                           list above for use again later.'),
  );

  $form['obo_new']['obo_url']= array(
    '#type'          => 'textfield',
    '#title'         => t('Remote URL'),
    '#description'   => t('Please enter a URL for the online OBO file.  The file will be downloaded and parsed.
                           (e.g. http://www.obofoundry.org/ro/ro.obo'),
  );

  $form['obo_new']['obo_file']= array(
    '#type'          => 'textfield',
    '#title'         => t('Local File'),
    '#description'   => t('Please enter the full system path for an OBO definition file, or a path within the Drupal
                           installation (e.g. /sites/default/files/xyz.obo).  The path must be accessible to the
                           server on which this Drupal instance is running.'),
  );

  $form['submit'] = array(
    '#type'         => 'submit',
    '#value'        => t('Submit'),
    '#executes_submit_callback' => TRUE,
  );

  $form['#redirect'] = 'admin/tripal/tripal_cv/obo_loader';

  return $form;
}

/**
 * The submit function for the load ontology form. It registers a
 *   tripal job to import the user specified ontology file
 *   
 * @param $form
 *   The form array 
 * @param $form_state
 *   The form state array
 *   
 * 
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_form_submit($form, &$form_state) {
  $obo_id =  $form_state['values']['obo_id'];
  $obo_name =  $form_state['values']['obo_name'];
  $obo_url =  $form_state['values']['obo_url'];
  $obo_file  = $form_state['values']['obo_file'];

  tripal_cv_submit_obo_job($obo_id, $obo_name, $obo_url, $obo_file);
}

/**
 * A wrapper function for importing the user specified OBO file into Chado by 
 * specifying the obo_id of the OBO. It requires that the file be in OBO v1.2 
 * compatible format.  This function is typically executed via the Tripal jobs 
 * management after a user submits a job via the Load Onotloies form.
 * 
 * @param $obo_id
 *   An obo_id from the tripal_cv_obo file that specifies which OBO file to import
 * @param $job_id
 *   The job_id of the job from the Tripal jobs management system. 
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_load_obo_v1_2_id($obo_id, $jobid = NULL) {

  // get the OBO reference
  $sql = "SELECT * FROM {tripal_cv_obo} WHERE obo_id = :obo_id";
  $obo = db_query($sql, array(':obo_id' => $obo_id))->fetchObject();

  // if the reference is for a remote URL then run the URL processing function
  if (preg_match("/^http:\/\//", $obo->path) or preg_match("/^ftp:\/\//", $obo->path)) {
    tripal_cv_load_obo_v1_2_url($obo->name, $obo->path, $jobid, 0);
  }
  // if the reference is for a local file then run the file processing function
  else {
    // check to see if the file is located local to Drupal
    $dfile = $_SERVER['DOCUMENT_ROOT'] . base_path() . $obo->path;
    if (file_exists($dfile)) {
      tripal_cv_load_obo_v1_2_file($obo->name, $dfile , $jobid, 0);
    }
    // if not local to Drupal, the file must be someplace else, just use
    // the full path provided
    else {
      if (file_exists($obo->path)) {
        tripal_cv_load_obo_v1_2_file($obo->name, $obo->path, $jobid, 0);
      }
      else {
        print "ERROR: counld not find OBO file: '$obo->path'\n";
      }
    }
  }
}

/**
 * A wrapper function for importing the user specified OBO file into Chado by 
 * specifying the filename and path of the OBO. It requires that the file be in OBO v1.2 
 * compatible format.  This function is typically executed via the Tripal jobs 
 * management after a user submits a job via the Load Onotloies form.
 * 
 * @param $obo_name
 *   The name of the OBO (typially the ontology or controlled vocabulary name)
 * @param $file
 *   The path on the file system where the ontology can be found
 * @param $job_id
 *   The job_id of the job from the Tripal jobs management system. 
 * @param $is_new
 *   Set to TRUE if this is a new ontology that does not yet exist in the 
 *   tripal_cv_obo table.  If TRUE the OBO will be added to the table.
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_load_obo_v1_2_file($obo_name, $file, $jobid = NULL, $is_new = TRUE) {
  $newcvs = array();

  // TODO: need better error detection

  tripal_cv_load_obo_v1_2($file, $jobid, $newcvs);
  if ($is_new) {
    tripal_cv_add_obo_ref($obo_name, $file);
  }
  print "\nDone\n";

  // update the cvtermpath table
  tripal_cv_load_update_cvtermpath($newcvs, $jobid);
}

/**
 * A wrapper function for importing the user specified OBO file into Chado by 
 * specifying the remote URL of the OBO. It requires that the file be in OBO v1.2 
 * compatible format.  This function is typically executed via the Tripal jobs 
 * management after a user submits a job via the Load Onotloies form.
 * 
 * @param $obo_name
 *   The name of the OBO (typially the ontology or controlled vocabulary name)
 * @param $url
 *   The remote URL of the OBO file.
 * @param $job_id
 *   The job_id of the job from the Tripal jobs management system. 
 * @param $is_new
 *   Set to TRUE if this is a new ontology that does not yet exist in the 
 *   tripal_cv_obo table.  If TRUE the OBO will be added to the table.
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_load_obo_v1_2_url($obo_name, $url, $jobid = NULL, $is_new = TRUE) {

  $newcvs = array();

  // first download the OBO
  $temp = tempnam(sys_get_temp_dir(), 'obo_');
  print "Downloading URL $url, saving to $temp\n";
  $url_fh = fopen($url, "r");
  $obo_fh = fopen($temp, "w");
  if (!$url_fh) {
    tripal_cv_obo_quiterror("Unable to download the remote OBO file at $url. Could a firewall be blocking outgoing connections? " .
      " if you are unable to download the file you may manually downlod the OBO file and use the web interface to " .
      " specify the location of the file on your server.");

  }
  while (!feof($url_fh)) {
    fwrite($obo_fh, fread($url_fh, 255), 255);
  }
  fclose($url_fh);
  fclose($obo_fh);

  // second, parse the OBO
  tripal_cv_load_obo_v1_2($temp, $jobid, $newcvs);

  // now remove the temp file
  unlink($temp);

  if ($is_new) {
    tripal_cv_add_obo_ref($obo_name, $url);
  }

  // update the cvtermpath table
  tripal_cv_load_update_cvtermpath($newcvs, $jobid);

  print "Done\n";
}

/**
 * A function for executing the cvtermpath function of Chado.  This function
 * populates the cvtermpath table of Chado for quick lookup of term 
 * relationships
 * 
 * @param $newcvs
 *   An associative array of controlled vocabularies to update.  The key must be
 *   the name of the vocabulary and the value the cv_id from the cv table of chado.
 * @param $jobid
 *   The job_id of the job from the Tripal jobs management system. 
 * 
 * @ingroup tripal_obo_loader
 */
function tripal_cv_load_update_cvtermpath($newcvs, $jobid) {

  print "\nUpdating cvtermpath table.  This may take a while...\n";
  foreach ($newcvs as $namespace => $cvid) {
    tripal_cv_update_cvtermpath($cvid, $jobid);
  }
}

/**
 * Imports a given OBO file into Chado.  This function is usually called by
 * one of three wrapper functions:  tripal_cv_load_obo_v1_2_id, 
 * tripal_cv_load_obo_v1_2_file or tirpal_cv_load_obo_v1_2_url. But, it can
 * be called directly if the full path to an OBO file is available on the 
 * file system.
 * 
 * @param $flie
 *   The full path to the OBO file on the file system
 * @param $jobid
 *   The job_id of the job from the Tripal jobs management system.
 * @param $newcvs
 *   An empty array passed by reference that upon return will contain the list 
 *   of newly added vocabularies.  The key will contain the CV name and the
 *   value the new cv_id
 * 
 * 
 * @ingroup tripal_obo_loader
 */
function tripal_cv_load_obo_v1_2($file, $jobid = NULL, &$newcvs) {

  $transaction = db_transaction();
  print "\nNOTE: Loading of this OBO file is performed using a database transaction. \n" .
      "If the load fails or is terminated prematurely then the entire set of \n" .
      "insertions/updates is rolled back and will not be found in the database\n\n";
  try {
    $header = array();

    // make sure our temporary table exists
    $ret = array();

    // empty the temp table
    $sql = "DELETE FROM {tripal_obo_temp}";
    chado_query($sql);

    print "Step 1: Preloading File $file\n";

    // make sure we have an 'internal' and a '_global' database
    if (!tripal_db_add_db('internal')) {
      tripal_cv_obo_quiterror("Cannot add 'internal' database");
    }
    if (!tripal_db_add_db('_global')) {
      tripal_cv_obo_quiterror("Cannot add '_global' database");
    }

    // parse the obo file
    $default_db = tripal_cv_obo_parse($file, $header, $jobid);

    // add the CV for this ontology to the database
    $defaultcv = tripal_cv_add_cv($header['default-namespace'][0], '');
    if (!$defaultcv) {
      tripal_cv_obo_quiterror('Cannot add namespace ' . $header['default-namespace'][0]);
    }
    $newcvs[$header['default-namespace'][0]] = $defaultcv->cv_id;

    // add any typedefs to the vocabulary first
    print "\nStep 2: Loading type defs...\n";
    tripal_cv_obo_load_typedefs($defaultcv, $newcvs, $default_db, $jobid);

    // next add terms to the vocabulary
    print "\nStep 3: Loading terms...\n";
    if (!tripal_cv_obo_process_terms($defaultcv, $jobid, $newcvs, $default_db)) {
      tripal_cv_obo_quiterror('Cannot add terms from this ontology');
    }
  }
  catch (Exception $e) {
    print "\n"; // make sure we start errors on new line
    watchdog_exception('T_obo_loader', $e);
    $transaction->rollback();
    print "FAILED: Rolling back database changes...\n";
    return 0;
  }

  return;
}

/**
 * Immediately terminates loading of the OBO file.
 * 
 * @param $message
 *   The error message to present to the user
 *   
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_quiterror($message) {

  tripal_report_error("T_obo_loader", TRIPAL_ERROR, $message, array());
  exit;

}

/**
 * OBO files are divided into a typedefs terms section and vocabulary terms section.  
 * This function loads the typedef terms from the OBO.
 * 
 * @param $defaultcv
 *   A database object containing a record from the cv table for the 
 *   default controlled vocabulary
 * @param $newcvs
 *   An associative array of controlled vocabularies for this OBO.  The key must be
 *   the name of the vocabulary and the value the cv_id from the cv table of chado.
 * @param $default_db
 *   The name of the default database.
 * @param $jobid
 *   The job_id of the job from the Tripal jobs management system.
 *   
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_load_typedefs($defaultcv, $newcvs, $default_db, $jobid) {
  $sql = "SELECT * FROM {tripal_obo_temp} WHERE type = 'Typedef' ";
  $typedefs = chado_query($sql);

  $sql = "
    SELECT count(*) as num_terms
    FROM {tripal_obo_temp}
    WHERE type = 'Typedef'
  ";
  $result = chado_query($sql)->fetchObject();
  $count = $result->num_terms;

  // calculate the interval for updates
  $interval = intval($count * 0.0001);
  if ($interval < 1) {
    $interval = 1;
  }
  $i = 0;
  foreach ($typedefs as $typedef) {
    $term = unserialize(base64_decode($typedef->stanza));

    // update the job status every interval
    if ($jobid and $i % $interval == 0) {
      $complete = ($i / $count) * 33.33333333;
      tripal_set_job_progress($jobid, intval($complete + 33.33333333));
      printf("%d of %d records. (%0.2f%%) Memory: %s bytes\r", $i, $count, $complete * 3, number_format(memory_get_usage()));
    }

    tripal_cv_obo_process_term($term, $defaultcv->name, 1, $newcvs, $default_db);

    $i++;
  }
    // set the final status
  if ($jobid) {
    if ($count > 0) {
      $complete = ($i / $count) * 33.33333333;
    }
    else {
      $complete = 33.33333333;
    }
    tripal_set_job_progress($jobid, intval($complete + 33.33333333));
    printf("%d of %d records. (%0.2f%%) Memory: %s bytes\r", $i, $count, $complete * 3, number_format(memory_get_usage()));
  }
  return 1;
}

/**
 * OBO files are divided into a typedefs section and a terms section.  This 
 * function loads the typedef terms from the OBO.
 * 
 * @param $defaultcv
 *   A database object containing a record from the cv table for the 
 *   default controlled vocabulary
 * @param $jobid
 *  The job_id of the job from the Tripal jobs management system.
 * @param $newcvs
 *   An associative array of controlled vocabularies for this OBO.  The key must be
 *   the name of the vocabulary and the value the cv_id from the cv table of chado.
 * @param $default_db
 *   The name of the default database.
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_process_terms($defaultcv, $jobid = NULL, &$newcvs, $default_db) {

  $i = 0;

  // iterate through each term from the OBO file and add it
  $sql = "
    SELECT * FROM {tripal_obo_temp}
    WHERE type = 'Term'
    ORDER BY id
  ";
  $terms = chado_query($sql);

  $sql = "
    SELECT count(*) as num_terms
    FROM {tripal_obo_temp}
    WHERE type = 'Term'
  ";
  $result = chado_query($sql)->fetchObject();
  $count = $result->num_terms;

  // calculate the interval for updates
  $interval = intval($count * 0.0001);
  if ($interval < 1) {
    $interval = 1;
  }
  foreach ($terms as $t) {
    $term = unserialize(base64_decode($t->stanza));

    // update the job status every interval
    if ($jobid and $i % $interval == 0) {
      $complete = ($i / $count) * 33.33333333;
      tripal_set_job_progress($jobid, intval($complete + 66.666666));
      printf("%d of %d records. (%0.2f%%) Memory: %s bytes\r", $i, $count, $complete * 3, number_format(memory_get_usage()));
    }

    // add/update this term
    if (!tripal_cv_obo_process_term($term, $defaultcv->name, 0, $newcvs, $default_db)) {
      tripal_cv_obo_quiterror("Failed to process terms from the ontology");
    }

    $i++;
  }

  // set the final status
  if ($jobid) {
    if ($count > 0) {
      $complete = ($i / $count) * 33.33333333;
    }
    else {
      $complete = 33.33333333;
    }
    tripal_set_job_progress($jobid, intval($complete + 66.666666));
    printf("%d of %d records. (%0.2f%%) Memory: %s bytes\r", $i, $count, $complete * 3, number_format(memory_get_usage()));
  }

  return 1;
}

/**
 * Uses the provided term array to add/update information to Chado about the 
 * term including the term, dbxref, synonyms, properties, and relationships.
 * 
 * @param $term
 *   An array representing the cvterm. 
 * @param $defaultcv
 *   A database object containing a record from the cv table for the 
 *   default controlled vocabulary
 * @is_relationship
 *   Set to 1 if this term is a relationship term
 * @default_db
 *   The name of the default database.
 * 
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_process_term($term, $defaultcv, $is_relationship = 0, &$newcvs, $default_db) {

  // construct the term array for sending to the tripal_cv_add_cvterm function
  // for adding a new cvterm
  $t = array();
  $t['id'] = $term['id'][0];
  $t['name'] = $term['name'][0];
  if (array_key_exists('def', $term)) {
    $t['def'] = $term['def'][0];
  }
  if (array_key_exists('subset', $term)) {
    $t['subset'] = $term['subset'][0];
  }
  if (array_key_exists('namespace', $term)) {
    $t['namespace'] = $term['namespace'][0];
  }
  if (array_key_exists('is_obsolete', $term)) {
    $t['is_obsolete'] = $term['is_obsolete'][0];
  }

  // add the cvterm
  $cvterm = tripal_cv_add_cvterm($t, $defaultcv, $is_relationship, 1, $default_db);
  if (!$cvterm) {
    tripal_cv_obo_quiterror("Cannot add the term " . $term['id'][0]);
  }

  if (array_key_exists('namespace', $term)) {
    $newcvs[$term['namespace'][0]] = $cvterm->cv_id;
  }

  // now handle other properites
  if (array_key_exists('is_anonymous', $term)) {
    //print "WARNING: unhandled tag: is_anonymous\n";
  }
  if (array_key_exists('alt_id', $term)) {
    foreach ($term['alt_id'] as $alt_id) {
      if (!tripal_cv_obo_add_cvterm_dbxref($cvterm, $alt_id)) {
        tripal_cv_obo_quiterror("Cannot add alternate id $alt_id");
      }
    }
  }

  if (array_key_exists('subset', $term)) {
    //print "WARNING: unhandled tag: subset\n";
  }
  // add synonyms for this cvterm
  if (array_key_exists('synonym', $term)) {
    if (!tripal_cv_obo_add_synonyms($term, $cvterm)) {
      tripal_cv_obo_quiterror("Cannot add synonyms");
    }
  }

  // reformat the deprecated 'exact_synonym, narrow_synonym, and broad_synonym'
  // types to be of the v1.2 standard
  if (array_key_exists('exact_synonym', $term) or array_key_exists('narrow_synonym', $term) or array_key_exists('broad_synonym', $term)) {
    if (array_key_exists('exact_synonym', $term)) {
      foreach ($term['exact_synonym'] as $synonym) {
        $new = preg_replace('/^\s*(\".+?\")(.*?)$/', '$1 EXACT $2', $synonym);
        $term['synonym'][] = $new;
      }
    }
    if (array_key_exists('narrow_synonym', $term)) {
      foreach ($term['narrow_synonym'] as $synonym) {
        $new = preg_replace('/^\s*(\".+?\")(.*?)$/', '$1 NARROW $2', $synonym);
        $term['synonym'][] = $new;
      }
    }
    if (array_key_exists('broad_synonym', $term)) {
      foreach ($term['broad_synonym'] as $synonym) {
        $new = preg_replace('/^\s*(\".+?\")(.*?)$/', '$1 BROAD $2', $synonym);
        $term['synonym'][] = $new;
      }
    }

    if (!tripal_cv_obo_add_synonyms($term, $cvterm)) {
      tripal_cv_obo_quiterror("Cannot add/update synonyms");
    }
  }

  // add the comment to the cvtermprop table
  if (array_key_exists('comment', $term)) {
    $comments = $term['comment'];
    $j = 0;
    foreach ($comments as $comment) {
      if (!tripal_cv_obo_add_cvterm_prop($cvterm, 'comment', $comment, $j)) {
        tripal_cv_obo_quiterror("Cannot add/update cvterm property");
      }
      $j++;
    }
  }

  // add any other external dbxrefs
  if (array_key_exists('xref', $term)) {
    foreach ($term['xref'] as $xref) {
      if (!tripal_cv_obo_add_cvterm_dbxref($cvterm, $xref)) {
        tripal_cv_obo_quiterror("Cannot add/update cvterm database reference (dbxref).");
      }
    }
  }

  if (array_key_exists('xref_analog', $term)) {
    foreach ($term['xref_analog'] as $xref) {
      if (!tripal_cv_obo_add_cvterm_dbxref($cvterm, $xref)) {
        tripal_cv_obo_quiterror("Cannot add/update cvterm database reference (dbxref).");
      }
    }
  }
  if (array_key_exists('xref_unk', $term)) {
    foreach ($term['xref_unk'] as $xref) {
      if (!tripal_cv_obo_add_cvterm_dbxref($cvterm, $xref)) {
        tripal_cv_obo_quiterror("Cannot add/update cvterm database reference (dbxref).");
      }
    }
  }

  // add is_a relationships for this cvterm
  if (array_key_exists('is_a', $term)) {
    foreach ($term['is_a'] as $is_a) {
      if (!tripal_cv_obo_add_relationship($cvterm, $defaultcv, 'is_a', $is_a, $is_relationship, $default_db)) {
        tripal_cv_obo_quiterror("Cannot add relationship is_a: $is_a");
      }
    }
  }

  if (array_key_exists('intersection_of', $term)) {
    //print "WARNING: unhandled tag: intersection_of\n";
  }
  if (array_key_exists('union_of', $term)) {
    //print "WARNING: unhandled tag: union_on\n";
  }
  if (array_key_exists('disjoint_from', $term)) {
    //print "WARNING: unhandled tag: disjoint_from\n";
  }
  if (array_key_exists('relationship', $term)) {
    foreach ($term['relationship'] as $value) {
      $rel = preg_replace('/^(.+?)\s.+?$/', '\1', $value);
      $object = preg_replace('/^.+?\s(.+?)$/', '\1', $value);
      if (!tripal_cv_obo_add_relationship($cvterm, $defaultcv, $rel, $object, $is_relationship, $default_db)) {
        tripal_cv_obo_quiterror("Cannot add relationship $rel: $object");
      }
    }
  }
  if (array_key_exists('replaced_by', $term)) {
   //print "WARNING: unhandled tag: replaced_by\n";
  }
  if (array_key_exists('consider', $term)) {
    //print "WARNING: unhandled tag: consider\n";
  }
  if (array_key_exists('use_term', $term)) {
    //print "WARNING: unhandled tag: user_term\n";
  }
  if (array_key_exists('builtin', $term)) {
    //print "WARNING: unhandled tag: builtin\n";
  }
  return 1;
}

/**
 * Adds a cvterm relationship
 * 
 * @param $cvterm
 *   A database object for the cvterm 
 * @param $rel
 *   The relationship name
 * @param $objname
 *   The relationship term name
 * @param $defaultcv
 *   A database object containing a record from the cv table for the 
 *   default controlled vocabulary
 * @object_is_relationship
 *   Set to 1 if this term is a relationship term
 * @default_db
 *   The name of the default database.
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_add_relationship($cvterm, $defaultcv, $rel,
  $objname, $object_is_relationship = 0, $default_db = 'OBO_REL') {

  // make sure the relationship cvterm exists
  $term = array(
    'name' => $rel,
    'id' => "$default_db:$rel",
    'definition' => '',
    'is_obsolete' => 0,
  );
  $relcvterm = tripal_cv_add_cvterm($term, $defaultcv, 1, 0, $default_db);

  if (!$relcvterm) {
    // if the relationship term couldn't be found in the default_db provided
    // then do on more check to find it in the relationship ontology
    $term = array(
      'name' => $rel,
      'id' => "OBO_REL:$rel",
      'definition' => '',
      'is_obsolete' => 0,
    );
    $relcvterm = tripal_cv_add_cvterm($term, $defaultcv, 1, 0, 'OBO_REL');
    if (!$relcvterm) {
      tripal_cv_obo_quiterror("Cannot find the relationship term in the current ontology or in the relationship ontology: $rel\n");
    }
  }

  // get the object term
  $oterm = tripal_cv_obo_get_term($objname);
  if (!$oterm) {
    tripal_cv_obo_quiterror("Could not find object term $objname\n");
  }

  $objterm = array();
  $objterm['id']            = $oterm['id'][0];
  $objterm['name']          = $oterm['name'][0];
  if (array_key_exists('def', $oterm)) {
    $objterm['def']           = $oterm['def'][0];
  }
  if (array_key_exists('subset', $oterm)) {
    $objterm['subset']      = $oterm['subset'][0];
  }
  if (array_key_exists('namespace', $oterm)) {
    $objterm['namespace']   = $oterm['namespace'][0];
  }
  if (array_key_exists('is_obsolete', $oterm)) {
    $objterm['is_obsolete'] = $oterm['is_obsolete'][0];
  }
  $objcvterm = tripal_cv_add_cvterm($objterm, $defaultcv, $object_is_relationship, 1, $default_db);
  if (!$objcvterm) {
    tripal_cv_obo_quiterror("Cannot add cvterm " . $oterm['name'][0]);
  }

  // check to see if the cvterm_relationship already exists, if not add it
  $values = array(
    'type_id'    => $relcvterm->cvterm_id,
    'subject_id' => $cvterm->cvterm_id,
    'object_id'  => $objcvterm->cvterm_id
  );
  $options = array('statement_name' => 'sel_cvtermrelationship_tysuob');
  $result = chado_select_record('cvterm_relationship', array('*'), $values, $options);
  if (count($result) == 0) {
    $options = array(
      'statement_name' => 'ins_cvtermrelationship_tysuob',
      'return_record' => FALSE
    );
    $success = chado_insert_record('cvterm_relationship', $values, $options);
    if (!$success) {
      tripal_cv_obo_quiterror("Cannot add term relationship: '$cvterm->name' $rel '$objcvterm->name'");
    }
  }

  return TRUE;
}

/**
 * Retreives the term array from the temp loading table for a given term id.
 * 
 * @param id
 *   The id of the term to retrieve
 *   
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_get_term($id) {
  $values = array('id' => $id);
  $options = array('statement_name' => 'sel_tripalobotemp_id');
  $result = chado_select_record('tripal_obo_temp', array('stanza'), $values, $options);
  if (count($result) == 0) {
    return FALSE;
  }
  return unserialize(base64_decode($result[0]->stanza));
}

/**
 * Adds the synonyms to a term
 * 
 * @param term
 *   An array representing the cvterm. It must have a 'synonym' key/value pair.
 * @param cvterm
 *   The database object of the cvterm to which the synonym will be added.
 * 
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_add_synonyms($term, $cvterm) {

  // make sure we have a 'synonym_type' vocabulary
  $syncv = tripal_cv_add_cv('synonym_type', 'A vocabulary added by the Tripal CV module OBO loader for storing synonym types.');

  // now add the synonyms
  if (array_key_exists('synonym', $term)) {
    foreach ($term['synonym'] as $synonym) {

      // separate out the synonym definition and the synonym type
      $def = preg_replace('/^\s*"(.*)"\s*.*$/', '\1', $synonym);
      // the scope will be 'EXACT', etc...
      $scope = drupal_strtolower(preg_replace('/^.*"\s+(.*?)\s+.*$/', '\1', $synonym));
      if (!$scope) {  // if no scope then default to 'exact'
        $scope = 'exact';
      }

      // make sure the synonym type exists in the 'synonym_type' vocabulary
      $values = array(
        'name' => $scope,
        'cv_id' => array(
          'name' => 'synonym_type',
        ),
      );
      $options = array('statement_name' => 'sel_cvterm_nacv', 'is_updlicate' => 1);
      $results = chado_select_record('cvterm', array('*'), $values, $options);

      // if it doesn't exist then add it
      if (!$results) {
        // build a 'term' object so we can add the missing term
        $term = array(
           'name' => $scope,
           'id' => "internal:$scope",
           'definition' => '',
           'is_obsolete' => 0,
        );
        $syntype = tripal_cv_add_cvterm($term, $syncv->name, 0, 1);
        if (!$syntype) {
          tripal_cv_obo_quiterror("Cannot add synonym type: internal:$scope");
        }
      }
      else {
        $syntype = $results[0];
      }

      // make sure the synonym doesn't already exists
      $values = array(
        'cvterm_id' => $cvterm->cvterm_id,
        'synonym' => $def
      );
      $options = array('statement_name' => 'sel_cvtermsynonym_cvsy');
      $results = chado_select_record('cvtermsynonym', array('*'), $values, $options);
      if (count($results) == 0) {
        $values = array(
          'cvterm_id' => $cvterm->cvterm_id,
          'synonym' => $def,
          'type_id' => $syntype->cvterm_id
        );
        $options = array(
          'statement_name' => 'ins_cvtermsynonym_cvsy',
          'return_record' => FALSE
        );
        $success = chado_insert_record('cvtermsynonym', $values, $options);
        if (!$success) {
          tripal_cv_obo_quiterror("Failed to insert the synonym for term: $name ($def)");
        }
      }

      // now add the dbxrefs for the synonym if we have a comma in the middle
      // of a description then this will cause problems when splitting os lets
      // just change it so it won't mess up our splitting and then set it back
      // later.
      /**
      $synonym = preg_replace('/(".*?),\s(.*?")/','$1,_$2',$synonym);
      $dbxrefs = preg_split("/, /",preg_replace('/^.*\[(.*?)\]$/','\1',$synonym));
      foreach ($dbxrefs as $dbxref) {
       $dbxref = preg_replace('/,_/',", ",$dbxref);
        if ($dbxref) {
          tripal_cv_obo_add_cvterm_dbxref($syn,$dbxref);
        }
      }
      */
    }
  }

  return TRUE;
}

/**
 * Parse the OBO file and populate the templ loading table
 *
 * @param $file
 *   The path on the file system where the ontology can be found 
 * @param $header
 *   An array passed by reference that will be populated with the header
 *   information from the OBO file
 * @param $jobid
 *   The job_id of the job from the Tripal jobs management system.
 * 
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_parse($obo_file, &$header, $jobid) {
  $in_header = 1;
  $stanza = array();
  $default_db = '_global';
  $line_num = 0;
  $num_read = 0;
  $intv_read = 0;

  $filesize = filesize($obo_file);
  $interval = intval($filesize * 0.01);
  if ($interval < 1) {
    $interval = 1;
  }

  // iterate through the lines in the OBO file and parse the stanzas
  $fh = fopen($obo_file, 'r');
  while ($line = fgets($fh)) {

    $line_num++;
    $size = drupal_strlen($line);
    $num_read += $size;
    $intv_read += $size;
    $line = trim($line);

    // update the job status every 1% features
    if ($jobid and $intv_read >= $interval) {
      $percent = sprintf("%.2f", ($num_read / $filesize) * 100);
      print "Parsing Line $line_num (" . $percent . "%). Memory: " . number_format(memory_get_usage()) . " bytes.\r";
      tripal_set_job_progress($jobid, intval(($num_read / $filesize) * 33.33333333));
      $intv_read = 0;
    }

    // remove newlines
    $line = rtrim($line);

    // remove any special characters that may be hiding
    $line = preg_replace('/[^(\x20-\x7F)]*/', '', $line);

    // skip empty lines
    if (strcmp($line, '') == 0) {
      continue;
    }

    //remove comments from end of lines
    $line = preg_replace('/^(.*?)\!.*$/', '\1', $line);  // TODO: if the explamation is escaped

    // at the first stanza we're out of header
    if (preg_match('/^\s*\[/', $line)) {
      $in_header = 0;

      // store the stanza we just finished reading
      if (sizeof($stanza) > 0) {
        // add the term to the temp table
        $values = array(
          'id' => $stanza['id'][0],
          'stanza' => base64_encode(serialize($stanza)),
          'type' => $type,
        );
        $options = array('statement_name' => 'ins_tripalobotemp_all');
        $success = chado_insert_record('tripal_obo_temp', $values, $options);
        if (!$success) {
          tripal_report_error('T_obo_loader', "ERROR: Cannot insert stanza into temporary table.", array(), 'error');
          exit;
        }

      }
      // get the stanza type:  Term, Typedef or Instance
      $type = preg_replace('/^\s*\[\s*(.+?)\s*\]\s*$/', '\1', $line);

      // start fresh with a new array
      $stanza = array();
      continue;
    }
    // break apart the line into the tag and value but ignore any escaped colons
    preg_replace("/\\:/", "|-|-|", $line); // temporarily replace escaped colons
    $pair = explode(":", $line, 2);
    $tag = $pair[0];
    $value = ltrim(rtrim($pair[1]));// remove surrounding spaces

    // if this is the ID then look for the default DB
    $matches = array();
    if ($tag == 'id' and preg_match('/^(.+?):.*$/', $value, $matches)) {
       $default_db = $matches[1];
    }

    $tag = preg_replace("/\|-\|-\|/", "\:", $tag); // return the escaped colon
    $value = preg_replace("/\|-\|-\|/", "\:", $value);
    if ($in_header) {
      if (!array_key_exists($tag, $header)) {
        $header[$tag] = array();
      }
      $header[$tag][] = $value;
    }
    else {
      if (!array_key_exists($tag, $stanza)) {
        $stanza[$tag] = array();
      }
      $stanza[$tag][] = $value;
    }
  }
  // now add the last term in the file
  if (sizeof($stanza) > 0) {
    $values = array(
      'id' => $stanza['id'][0],
      'stanza' => base64_encode(serialize($stanza)),
      'type' => $type,
    );
    $options = array('statement_name' => 'ins_tripalobotemp_all');
    chado_insert_record('tripal_obo_temp', $values, $options);
    if (!$success) {
      tripal_report_error('T_obo_loader', "ERROR: Cannot insert stanza into temporary table.", array(), 'error');
      exit;
    }
    $percent = sprintf("%.2f", ($num_read / $filesize) * 100);
    print "Parsing Line $line_num (" . $percent . "%). Memory: " . number_format(memory_get_usage()) . " bytes.\r";
    tripal_set_job_progress($jobid, intval(($num_read / $filesize) * 33.33333333));
  }
  return $default_db;
}

/**
 * Adds a database reference to a cvterm
 * 
 * @param cvterm
 *   The database object of the cvterm to which the synonym will be added.
 * @param xref
 *   The cross refernce.  It should be of the form from the OBO specification
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_add_cvterm_dbxref($cvterm, $xref) {

  $dbname = preg_replace('/^(.+?):.*$/', '$1', $xref);
  $accession = preg_replace('/^.+?:\s*(.*?)(\{.+$|\[.+$|\s.+$|\".+$|$)/', '$1', $xref);
  $description = preg_replace('/^.+?\"(.+?)\".*?$/', '$1', $xref);
  $dbxrefs = preg_replace('/^.+?\[(.+?)\].*?$/', '$1', $xref);

  if (!$accession) {
    tripal_cv_obo_quiterror();
    tripal_report_error("T_obo_loader", TRIPAL_WARNING, "Cannot add a dbxref without an accession: '$xref'", NULL);
    return FALSE;
  }

  // if the xref is a database link, handle that specially
  if (strcmp($dbname, 'http') == 0) {
    $accession = $xref;
    $dbname = 'URL';
  }

  // add the database
  $db = tripal_db_add_db($dbname);
  if (!$db) {
    tripal_cv_obo_quiterror("Cannot find database '$dbname' in Chado.");
  }

  // now add the dbxref
  $dbxref = tripal_cv_obo_add_dbxref($db->db_id, $accession, '', $description);
  if (!$dbxref) {
    tripal_cv_obo_quiterror("Cannot find or add the database reference (dbxref)");
  }

  // finally add the cvterm_dbxref but first check to make sure it exists
  $values = array(
    'cvterm_id' => $cvterm->cvterm_id,
    'dbxref_id' => $dbxref->dbxref_id,
  );
  $options = array('statement_name' => 'sel_cvtermdbxref_cvdb');
  $result = chado_select_record('cvterm_dbxref', array('*'), $values, $options);
  if (count($result) == 0) {
    $ins_options = array(
      'statement_name' => 'ins_cvtermdbxref_cvdb',
      'return_record' => FALSE
    );
    $result = chado_insert_record('cvterm_dbxref', $values, $ins_options);
    if (!$result) {
      tripal_cv_obo_quiterror("Cannot add cvterm_dbxref: $xref");
      return FALSE;
    }
  }

  return TRUE;
}

/**
 * Adds a property to a cvterm
 * 
 * @param cvterm
 *   A database object for the cvterm to which properties will be added
 * @param $property
 *   The name of the property to add
 * @param $value 
 *   The value of the property
 * @param rank
 *   The rank of the property
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_add_cvterm_prop($cvterm, $property, $value, $rank) {

  // make sure the 'cvterm_property_type' CV exists
  $cv = tripal_cv_add_cv('cvterm_property_type', '');
  if (!$cv) {
    tripal_cv_obo_quiterror("Cannot add/find cvterm_property_type cvterm");
  }

  // get the property type cvterm.  If it doesn't exist then we want to add it
  $values = array(
    'name' => $property,
    'cv_id' => $cv->cv_id,
  );
  $options = array('statement_name' => 'sel_cvterm_nacv_na');
  $results = chado_select_record('cvterm', array('*'), $values, $options);
  if (count($results) == 0) {
    $term = array(
      'name' => $property,
      'id' => "internal:$property",
      'definition' => '',
      'is_obsolete' => 0,
    );
    $cvproptype = tripal_cv_add_cvterm($term, $cv->name, 0, 0);
    if (!$cvproptype) {
      tripal_cv_obo_quiterror("Cannot add cvterm property: internal:$property");
      return FALSE;
    }
  }
  else {
    $cvproptype = $results[0];
  }

  // remove any properties that currently exist for this term.  We'll reset them
  if ($rank == 0) {
    $values = array('cvterm_id' => $cvterm->cvterm_id);
    $options = array('statement_name' => 'del_cvtermprop_cv');
    $success = chado_delete_record('cvtermprop', $values, $options);
    if (!$success) {
       tripal_cv_obo_quiterror("Could not remove existing properties to update property $property for term\n");
       return FALSE;
    }
  }

  // now add the property
  $values = array(
    'cvterm_id' => $cvterm->cvterm_id,
    'type_id' => $cvproptype->cvterm_id,
    'value' => $value,
    'rank' => $rank,
  );
  $options = array(
    'statement_name' => 'ins_cvtermprop_cvtyvara',
    'return_record' => FALSE,
  );
  $result = chado_insert_record('cvtermprop', $values, $options);
  if (!$result) {
    tripal_cv_obo_quiterror("Could not add property $property for term\n");
    return FALSE;
  }
  return TRUE;
}

/**
 * Adds a database cross reference to a cvterm
 * 
 * @param db_id
 *   The database ID of the cross reference
 * @param accession
 *   The cross reference's accession
 * @param $version
 *   The version of the dbxref
 * @param $description
 *   The description of the cross reference
 *
 * @ingroup tripal_obo_loader
 */
function tripal_cv_obo_add_dbxref($db_id, $accession, $version='', $description='') {

  // check to see if the dbxref exists if not, add it
  $values = array(
    'db_id' => $db_id,
    'accession' => $accession,
  );
  $options = array('statement_name' => 'sel_dbxref_idac');
  $result = chado_select_record('dbxref', array('dbxref_id'), $values, $options);
  if (count($result) == 0) {
    $ins_values = array(
      'db_id'       => $db_id,
      'accession'   => $accession,
      'version'     => $version,
      'description' => $description,
    );
    $ins_options = array(
      'statement_name' => 'ins_dbxref_idacvede',
      'return_record' => FALSE
    );
    $result = chado_insert_record('dbxref', $ins_values, $ins_options);
    if (!$result) {
      tripal_cv_obo_quiterror("Failed to insert the dbxref record $accession");
      return FALSE;
    }
    $result = chado_select_record('dbxref', array('dbxref_id'), $values, $options);
  }
  return $result[0];
}