<?php

/*******************************************************************************
*  Implementation of hook_install();
*/
function tripal_cv_install(){

   // create the module's data directory
   tripal_create_moddir('tripal_cv');

   // Add the materialized view needed to keep track of the 
   // 
   $previous_db = db_set_active('chado');
   if (db_table_exists('cv_root_mview')) {
      $sql = "DROP TABLE cv_root_mview";
      db_query($sql);
   }
   db_set_active($previous_db);
   // Create the MView
   tripal_add_mview(
      // view name
      'cv_root_mview',
      // module name  
      'tripal_cv',
      // table name
      'cv_root_mview',
      // table schema
      'name character varying(1024), cvterm_id integer, cv_id integer, 
       cv_name character varying(255)',
      // indexed columns
      'cvterm_id, cv_id',
      // SQL statement that populates the view
      'SELECT DISTINCT CVT.name,CVT.cvterm_id, CV.cv_id, CV.name
       FROM {cvterm_relationship} CVTR
         INNER JOIN cvterm CVT on CVTR.object_id = CVT.cvterm_id
         INNER JOIN CV on CV.cv_id = CVT.cv_id
       WHERE CVTR.object_id not in
         (SELECT subject_id FROM {cvterm_relationship}) ',
      // special index
      ''
   );

}

/*******************************************************************************
* Implementation of hook_uninstall()
*/
function tripal_cv_uninstall(){

	// remove the materialized view
   $mview = tripal_mviews_get_mview_id('cv_root_mview');
   if($mview){
	   tripal_mviews_action('delete',$mview);
	}
}

/*******************************************************************************
 * Implementation of hook_requirements(). Make sure 'Tripal Core' is enabled
 * before installation
 */
function tripal_cv_requirements($phase) {
   $requirements = array();
   if ($phase == 'install') {
      if (!function_exists('tripal_create_moddir')) {
         $requirements ['tripal_cv'] = array(
            'title' => "tripal_cv",
            'value' => "Required modules must be installed first before Tripal CV module can be installed",
            'severity' => REQUIREMENT_ERROR,
         );
      }
   }
   return $requirements;
}