<?php

if (! defined('BASEPATH')) exit('No direct script access allowed');

/**
 *
 */
class SearchBarLib
{
	// 
	const ERROR_WRONG_JSON = 'ERR001';
	const ERROR_WRONG_SEARCHSTR = 'ERR002';
	const ERROR_NO_TYPES = 'ERR003';
	const ERROR_WRONG_TYPES = 'ERR004';

	// List of allowed types of search
	const ALLOWED_TYPES = ['mitarbeiter', 'organisationunit', 'raum', 'person', 'student', 'prestudent', 'document', 'cms'];

	private $_ci; // Code igniter instance

	/**
	 * Gets the CI instance and loads model
	 */
	public function __construct()
	{
		$this->_ci =& get_instance(); // get code igniter instance

		// It is loaded only to have the DB_Model available
		$this->_ci->load->model('person/Benutzer_model', 'BenutzerModel');
	}

	//------------------------------------------------------------------------------------------------------------------
	// Public methods

	/**
	 * It performes the search of the given search string using the specified search types
	 */
	public function search($searchstr, $types)
	{
		// Checks if the given parameters are fine
		$search = $this->_checkParameters($searchstr, $types);

		// If the check was successful then perform the search
		if (isSuccess($search)) $search = $this->_search($searchstr, $types);

		return $search; // return the result
	}

	//------------------------------------------------------------------------------------------------------------------
	// Private methods

	/**
	 * Checks:
	 * - The given searchstr is a not empty string
	 * - The given types is a not empty array and contains allowed search types
	 */
	private function _checkParameters($searchstr, $types)
	{
		// If searchstr is empty
		if (isEmptyString($searchstr)) return error(self::ERROR_WRONG_SEARCHSTR);

		// If types is not an array or it is empty
		if (isEmptyArray($types)) return error(self::ERROR_NO_TYPES);

		// If all the elements in types are allowed search types
		if (!isEmptyArray(array_diff($types, self::ALLOWED_TYPES))) return error(self::ERROR_WRONG_TYPES);

		return success(); // The check is fine!
	}

	/**
	 * Loops on types and perform the search of that type using searchstr
	 * Then it collects all the returned data into an array as property of an object
	 */
	private function _search($searchstr, $types)
	{
		// Object to be returned
		$result = new stdClass();
		$result->data = array();

		// For each search type
		foreach ($types as $type)
		{
			// Perform the search and then add the result to data
			$result->data = array_merge($result->data, $this->{'_'.$type}($searchstr, $type));
		}

		return $result;
	}

	/**
	 * Search for employees
	 */
	private function _mitarbeiter($searchstr, $type)
	{
		$dbModel = new DB_Model();

		$employees = $dbModel->execReadOnlyQuery('
			SELECT
				\''.$type.'\' AS type,
				b.uid AS uid,
				p.person_id AS person_id,
				p.vorname || \' \' || p.nachname AS name,
				ARRAY_AGG(DISTINCT(org.bezeichnung)) AS organisationunit_name,
				b.uid || \''.'@'.DOMAIN.'\' AS email,
				m.telefonklappe AS phone
			  FROM public.tbl_mitarbeiter m
			  JOIN public.tbl_benutzer b ON(b.uid = m.mitarbeiter_uid)
			  JOIN public.tbl_person p USING(person_id)
			  JOIN (
				SELECT o.bezeichnung, bf.uid
				  FROM public.tbl_benutzerfunktion bf
				  JOIN public.tbl_organisationseinheit o USING(oe_kurzbz)
				 WHERE (bf.datum_von IS NULL OR bf.datum_von <= NOW())
				   AND (bf.datum_bis IS NULL OR bf.datum_bis >= NOW())
				GROUP BY o.bezeichnung, bf.uid
			) org USING(uid)
			 WHERE b.uid ILIKE \'%'.$dbModel->escapeLike($searchstr).'%\'
			    OR p.vorname ILIKE \'%'.$dbModel->escapeLike($searchstr).'%\'
			    OR p.nachname ILIKE \'%'.$dbModel->escapeLike($searchstr).'%\'
		      GROUP BY type, b.uid, p.person_id, name, email, m.telefonklappe
		');

		// If something has been found then return it
		if (hasData($employees)) return getData($employees);

		// Otherwise return an empty array
		return array();
	}

	/**
	 * Seach for organisation units
	 */
	private function _organisationunit($searchstr, $type)
	{
		$dbModel = new DB_Model();

		$ous = $dbModel->execReadOnlyQuery('
			SELECT
				\''.$type.'\' AS type,
				o.oe_kurzbz AS oe_kurzbz,
				o.bezeichnung AS name,
				oParent.oe_kurzbz AS parentoe_kurzbz,
				oParent.bezeichnung AS parentoe_name,
				ARRAY_AGG(DISTINCT(bfLeader.uid)) AS leader_uid,
				ARRAY_AGG(DISTINCT(p.vorname || \' \' || p.nachname)) AS leader_name,
				COUNT(bfCount.benutzerfunktion_id) AS number_of_people
			  FROM public.tbl_organisationseinheit o
		     LEFT JOIN public.tbl_organisationseinheit oParent ON(oParent.oe_kurzbz = o.oe_parent_kurzbz)
		     LEFT JOIN (
				SELECT benutzerfunktion_id, oe_kurzbz, uid
				  FROM public.tbl_benutzerfunktion
				 WHERE (datum_von IS NULL OR datum_von <= NOW())
				   AND (datum_bis IS NULL OR datum_bis >= NOW())
			) bfCount ON(bfCount.oe_kurzbz = o.oe_kurzbz)
		     LEFT JOIN (
				SELECT oe_kurzbz, uid
				  FROM public.tbl_benutzerfunktion
				 WHERE funktion_kurzbz = \'Leitung\'
				   AND (datum_von IS NULL OR datum_von <= NOW())
				   AND (datum_bis IS NULL OR datum_bis >= NOW())
			) bfLeader ON(bfLeader.oe_kurzbz = o.oe_kurzbz)
		     LEFT JOIN public.tbl_benutzer b ON(b.uid = bfLeader.uid)
		     LEFT JOIN public.tbl_person p USING(person_id)
			 WHERE b.aktiv = TRUE
			   AND o.oe_kurzbz ILIKE \'%'.$dbModel->escapeLike($searchstr).'%\'
			    OR o.bezeichnung ILIKE \'%'.$dbModel->escapeLike($searchstr).'%\'
		      GROUP BY type, o.oe_kurzbz, o.bezeichnung, oParent.oe_kurzbz, oParent.bezeichnung
		');

		// If something has been found then return it
		if (hasData($ous)) return getData($ous);

		// Otherwise return an empty array
		return array();
	}

	/**
	 * Search for persons
	 */
	private function _person($searchstr, $type)
	{
		return array();
	}

	/**
	 * Search for students
	 */
	private function _student($searchstr, $type)
	{
		return array();
	}

	/**
	 * Search for prestudents
	 */
	private function _prestudent($searchstr, $type)
	{
		return array();
	}

	/**
	 * Search for documents
	 */
	private function _document($searchstr, $type)
	{
		return array();
	}

	/**
	 * Search for CMSs
	 */
	private function _cms($searchstr, $type)
	{
		return array();
	}

	/**
	 * Search for rooms
	 */
	private function _raum($searchstr, $type)
	{
		return array();
	}
}