if (!empty($year))
            $query->set('year', $cDate['year']);

        if (!empty($monthnum))
            $query->set('monthnum', $cDate['mon']);

        if (!empty($day))
            $query->set('day', $cDate['mday']);

        return $query;
    }

    if (!empty($year) and ! empty($monthnum) and ! empty($day)) {
        $post_date = jalali_to_gregorian($year, $monthnum, $day);
        $query->set('year', $post_date[0]);
        $query->set('monthnum', $post_date[1]);
        $query->set('day', $post_date[2]);
        return $query;
    }

    if (!empty($year) and ! empty($monthnum)) {
        $start_date = jalali_to_gregorian($year, $monthnum, 1);
        $end_date = jalali_to_gregorian($year, $monthnum, jday_of_month($year, $monthnum));

        $date_query = array(
            array(
                'after' => array(
                    'year' => $start_date[0],
                    'month' => $start_date[1],
                    'day' => $start_date[2],
                ),
                'before' => array(
                    'year' => $end_date[0],
                    'month' => $end_date[1],
                    'day' => $end_date[2],
                ),
                'inclusive' => TRUE,
            ),
        );
        $query->set('date_query', $date_query);
        $query->set('year', '');
        $query->set('monthnum', '');

//        $post_date = jalali_to_gregorian($year, $monthnum, 15);
//        $query->set('year', $post_date[0]);
//        $query->set('monthnum', $post_date[1]);
        return $query;
    }

    if (!empty($year)) {
        $start_date = jalali_to_gregorian($year, 1, 1);
        if (is_jalali_leap_year($year))
            $end_date = jalali_to_gregorian($year, 12, 30);
        else
            $end_date = jalali_to_gregorian($year, 12, 29);
        $date_query = array(
            array(
                'after' => array(
                    'year' => $start_date[0],
                    'month' => $start_date[1],
                    'day' => $start_date[2],
                ),
                'before' => array(
                    'year' => $end_date[0],
                    'month' => $end_date[1],
                    'day' => $end_date[2],
                ),
                'inclusive' => TRUE,
            ),
        );
        $query->set('date_query', $date_query);
        $query->set('year', '');
        return $query;
    }

    return $query;
}

/* =================================================================== */

/**
 * jalali link filter handlers
 * @param string $perma
 * @param string $post
 * @param string $leavename
 * @see wp-includes\link-template.php line 112
 */
function ztjalali_permalink_filter_fn($perma, $post, $leavename = false) {
    $permalink = get_option('permalink_structure');
    if (empty($permalink))
        return $perma;
    if(!(preg_match('/%year%|%monthnum%|%day%/', $permalink)))
        return $perma;
    /* ------------------------------------------------------ */
    if (empty($post->ID))
        return $perma;
    /* ------------------------------------------------------ */
    if (in_array($post->post_status, array('draft', 'pending', 'auto-draft')))
        return $perma;
    /* ------------------------------------------------------ */
    $illegal_post_types = get_post_types(array('_builtin' => false));
    $illegal_post_types[] ='page';
    $illegal_post_types[] ='attachment';
    if (in_array($post->post_type,$illegal_post_types))
        return $perma;
    /* ------------------------------------------------------ */
    $rewritecode = array(
        '%year%',
        '%monthnum%',
        '%day%',
        '%hour%',
        '%minute%',
        '%second%',
        $leavename ? '' : '%postname%',
        '%post_id%',
        '%category%',
        '%author%',
        $leavename ? '' : '%pagename%',
    );

    $unixtime = strtotime($post->post_date);
    $category = "";
    if (strpos($permalink, '%category%') !== false) {
        $cats = get_the_category($post->ID);
        if ($cats) {
            usort($cats, '_usort_terms_by_ID'); // order by ID
            $category_object = get_term(reset($cats), 'category');
            $category = $category_object->slug;
            if ($parent = $category_object->parent)
                $category = get_category_parents($parent, false, '/', true) . $category;
        }
        if (empty($category)) {
            $default_category = get_term(get_option('default_category'), 'category');
            $category = is_wp_error($default_category) ? '' : $default_category->slug;
        }
    }

    $author = "";
    if (strpos($permalink, '%author%') !== false) {
        $authordata = get_user_by('id', $post->post_author);
        if(!empty($authordata))
            $author = $authordata->user_nicename;
    }

    $date = explode("-", date('Y-m-d-H-i-s', $unixtime));
    $jdate = gregorian_to_jalali($date[0], $date[1], $date[2]);
    $rewritereplace = array(
        $jdate[0],
        sprintf('%02d', $jdate[1]), // add leading zero if necessary
        sprintf('%02d', $jdate[2]),
        $date[3],
        $date[4],
        $date[5],
        $post->post_name,
        $post->ID,
        $category,
        $author,
        $post->post_name,
    );
    $permalink = home_url(str_replace($rewritecode, $rewritereplace, $permalink));
    return user_trailingslashit($permalink, 'single');
}

/* =================================================================== */