<?php
class News_model extends DB_Model
{

	/**
	 * Constructor
	 */
	public function __construct()
	{
		parent::__construct();
		$this->dbTable = 'campus.tbl_news';
		$this->pk = 'news_id';
	}

	/**
	 * Get all News ordered by date. (most actual on top)
	 * @param null $limit   Amount of news.
	 * @return array
	 */
	public function getAll($limit = null)
	{
		$this->addJoin("campus.tbl_content","content_id");

		return $this->execReadOnlyQuery('
			SELECT *, TO_CHAR(campus.tbl_news.datum, ?) as datumformatted
			FROM campus.tbl_news
			JOIN campus.tbl_content content ON content.content_id = campus.tbl_news.content_id
			WHERE 
			--text IS NOT NULL AND 	
			datum <= NOW() AND (datum_bis >= NOW()::date OR datum_bis IS NULL) AND
			(NOW()-datum) < interval \'' . MAXNEWSALTER . ' days\'
			ORDER BY datum DESC, campus.tbl_news.updateamum DESC
			LIMIT ' . $this->escape($limit)
		, ['DD/MM/YYYY']);
	}

	public function getNewsContentIDs($limit=10){
		$this->addSelect(['content_id']);
		return $this->loadWhere("datum <= NOW() AND (datum_bis IS NULL OR datum_bis >= now()::date)
		ORDER BY datum DESC
		LIMIT " . $this->escape($limit));

	}


	/**
	 * @param string            $sprache
	 * @param string            $studiengang_kz
	 * @param integer | null    $semester
	 * @param string            $fachbereich_kurzbz
	 * @param boolean           $sichtbar
	 * @param integer           $page
	 * @param integer           $page_size
	 * @param boolean           $active
	 * @param boolean           $mischen
	 * 
	 * TODO(chris): this is not a good function -> the params are all over the place
	 * 
	 */
	protected function prepareNewsWithContent($sprache, $studiengang_kz, $semester, $fachbereich_kurzbz = null, $sichtbar = true, $page = 1, $page_size = 10, $active = true, $mischen = true, $filterForDegreePrograms = false, $allowedDegreePrograms = [])
	{

		$this->addSelect(["*", "COUNT(*) OVER() AS row_count"]);
		$this->addOrder('datum', 'DESC');
		$this->addOrder('tbl_news.updateamum', 'DESC');

		$studiengang_kz = trim($studiengang_kz);
		$fachbereich_kurzbz = trim($fachbereich_kurzbz);

		$where = [];
		
		if ($active) {
			$where[] = "(datum <= NOW()::date AND (datum_bis >= NOW()::date OR (datum_bis IS NULL AND (NOW()-datum) < interval '" . MAXNEWSALTER . " days')))";
		}
		if ($fachbereich_kurzbz != '*') {
			if ($fachbereich_kurzbz == '') {
				$where[] = "fachbereich_kurzbz IS NULL";
			} else {
				$where[] = "fachbereich_kurzbz = " . $this->db->escape($fachbereich_kurzbz);

			}
		}

		$sgAndSemesterCondition = [];

		if ($studiengang_kz !== '') {
			$sgAndSemesterCondition[] = 'studiengang_kz = ' . $this->db->escape($studiengang_kz);
		}
		if ($semester !== null && $semester !== 0) {
			$sgAndSemesterCondition[] = 'semester = ' . $this->db->escape($semester);
		}

		$targetedSgAndSemesterCondition = [];

		if (!empty($sgAndSemesterCondition)) {
			$targetedSgAndSemesterCondition[] = '(' . implode(' AND ', $sgAndSemesterCondition) . ')';
		}
		if ($mischen === true) {
			$targetedSgAndSemesterCondition[] = '(studiengang_kz = 0 AND (semester = 0 OR semester IS NULL))';

			if ($semester !== null && $semester !== 0) {
				$targetedSgAndSemesterCondition[] = '(studiengang_kz = 0 AND semester = ' . $this->db->escape($semester) . ')';
			}
		}

		$finalSgAndSemesterCondition = implode(' OR ', $targetedSgAndSemesterCondition);

		if ($finalSgAndSemesterCondition !== '') {
			$where[] = "(" . $finalSgAndSemesterCondition . ")";
		}

		$this->addJoin('campus.tbl_contentsprache cs', 'content_id');

		if (is_bool($sichtbar) || $sichtbar === 'true' || $sichtbar === 'false') {
			$isSichtbar = filter_var($sichtbar, FILTER_VALIDATE_BOOLEAN);
			$where[] = "cs.sichtbar = " . ($isSichtbar ? "true" : "false");
		}

		$where[] = "cs.sprache = (CASE WHEN EXISTS(SELECT 1 FROM campus.tbl_contentsprache cs2 WHERE cs2.content_id=" . $this->dbTable . ".content_id AND sprache=" . $this->db->escape($sprache) . ") THEN " . $this->db->escape($sprache) . " ELSE " . $this->db->escape(DEFAULT_LANGUAGE) . " END)";


		$where[] = "cs.version = (SELECT MAX(version) FROM campus.tbl_contentsprache cs3 WHERE cs3.content_id=" . $this->dbTable . ".content_id AND cs3.sprache = (CASE WHEN EXISTS(SELECT 1 FROM campus.tbl_contentsprache cs2 WHERE cs2.content_id=" . $this->dbTable . ".content_id AND sprache=" . $this->db->escape($sprache) . ") THEN " . $this->db->escape($sprache) . " ELSE " . $this->db->escape(DEFAULT_LANGUAGE) . " END))";

		if ($filterForDegreePrograms) {
			if (empty($allowedDegreePrograms)) {
				$where[] = "1=0";
			} else {
				$where[] = "studiengang_kz IN (" . implode(',', array_map([$this->db, 'escape'], $allowedDegreePrograms)) . ")";
			}
		}

		$where = implode(" AND ", $where);

		$this->db->where($where, NULL, FALSE);

	}

	public function getNewsWithContent($sprache, $studiengang_kz, $semester, $fachbereich_kurzbz = null, $sichtbar = true, $page = 1, $page_size = 10, $active = true, $mischen = true, $filterForDegreePrograms = false, $allowedDegreePrograms = [])
	{
		$this->prepareNewsWithContent($sprache, $studiengang_kz, $semester, $fachbereich_kurzbz, $sichtbar, $page, $page_size, $active, $mischen, $filterForDegreePrograms, $allowedDegreePrograms);
		// getting the number of rows of the query and adding pagination to the query result
		$num_rows = $this->getNumRows(true);
		$this->addPagination($page, $page_size, $num_rows);

		// preparing the query again because every call to get_compiled_select or cour_all_results will add the from clause to the query
		$this->prepareNewsWithContent($sprache, $studiengang_kz, $semester, $fachbereich_kurzbz, $sichtbar, $page, $page_size, $active, $mischen, $filterForDegreePrograms, $allowedDegreePrograms);

		return $this->load();
	}
}