WordPress Hierarchical Permalinks

<?php

function keha_add_rewrite_rules() {

    global $wp_rewrite;

    $taxonomies = get_taxonomies( array( '_builtin' => false ) );

    if( empty( $taxonomies ) ) {
        return false;
    }

    foreach ( $taxonomies as $taxonomy ) {

        $tax_obj = get_taxonomy( $taxonomy );
        $post_types = $tax_obj->object_type;

        foreach ( $post_types as $post_type ) {

            $post_type_obj = get_post_type_object( $post_type );


            $slug = $post_type_obj->rewrite['slug'];

            if( !$slug ) {
                $slug = $post_type;
            }

            if( is_string( $post_type_obj->has_archive ) ) {
                $slug = $post_type_obj->has_archive;
            };


            if ( isset( $tax_obj->rewrite['slug'] ) ) {

                $tax_pat = $tax_obj->rewrite['slug'];

            } else {

                $tax_pat = $taxonomy;

            }

            $tax = $taxonomy;

            add_rewrite_rule( $slug . '/' . $tax_pat . '/(.+?)/page/?([0-9]{1,})/?$', 'index.php?' . $tax . '=$matches[1]&paged=$matches[2]', 'top' );
            add_rewrite_rule( $slug . '/' . $tax_pat . '/(.+?)/feed/(feed|rdf|rss|rss2|atom)/?$', 'index.php?' . $tax . '=$matches[1]&feed=$matches[2]', 'top' );
            add_rewrite_rule( $slug . '/' . $tax_pat . '/(.+?)/(feed|rdf|rss|rss2|atom)/?$', 'index.php?' . $tax . '=$matches[1]&feed=$matches[2]', 'top' );
            add_rewrite_rule( $slug . '/' . $tax_pat . '/(.+?)/?$', 'index.php?' . $tax . '=$matches[1]', 'top' );
            add_rewrite_rule( $tax_pat . '/(.+?)/date/([0-9]{4})/([0-9]{1,2})/?$', 'index.php?' . $tax . '=$matches[1]&year=$matches[2]&monthnum=$matches[3]&post_type=' . $post_type, 'top' );
            add_rewrite_rule( $tax_pat . '/(.+?)/date/([0-9]{4})/([0-9]{1,2})/page/?([0-9]{1,})/?$', 'index.php?' . $tax . '=$matches[1]&year=$matches[2]&monthnum=$matches[3]&paged=$matches[4]&post_type=' . $post_type, 'top' );
            add_rewrite_rule( $slug . '/' . $tax_pat . '/(.+?)/date/([0-9]{4})/([0-9]{1,2})/?$', 'index.php?' . $tax . '=$matches[1]&year=$matches[2]&monthnum=$matches[3]&post_type=' . $post_type, 'top' );
            add_rewrite_rule( $slug . '/' . $tax_pat . '/(.+?)/date/([0-9]{4})/([0-9]{1,2})/page/?([0-9]{1,})/?$', 'index.php?' . $tax . '=$matches[1]&year=$matches[2]&monthnum=$matches[3]&paged=$matches[4]&post_type=' . $post_type, 'top' );

        }
    }
}
add_action( 'wp_loaded', 'keha_add_rewrite_rules' );

function keha_post_type_link( $post_link, $post, $leavename ) {

    global $wp_rewrite;

    $draft_or_pending = isset( $post->post_status ) && in_array( $post->post_status, array( 'draft', 'pending', 'auto-draft' ) );
    if( $draft_or_pending and !$leavename )
        return $post_link;

    $post_type = $post->post_type;
    $permalink = $wp_rewrite->get_extra_permastruct( $post_type );
    $permalink = str_replace( '%post_id%', $post->ID, $permalink );
    $permalink = str_replace( '%'.$post_type.'_slug%', get_post_type_object( $post_type )->rewrite['slug'], $permalink );

    $parents_dirs = "";

    if( !$leavename ){
        $postId = $post->ID;
        while ( $parent = get_post( $postId )->post_parent) {
            $parents_dirs = get_post( $parent )->post_name."/".$parents_dirs;
            $postId = $parent;
        }
    }

    $permalink = str_replace( '%'.$post_type.'%', $parents_dirs.'%'.$post_type.'%', $permalink );

    if( !$leavename ){
        $permalink = str_replace( '%'.$post_type.'%', $post->post_name, $permalink );
    }

    $taxonomies = get_taxonomies( array( 'show_ui' => true ),'objects' );

    // %taxonomy% -> parent/child
    foreach ( $taxonomies as $taxonomy => $objects ) {

        if ( strpos( $permalink, "%$taxonomy%" ) !== false ) {

            $terms = wp_get_post_terms( $post->ID, $taxonomy, array('orderby' => 'term_id'));

            if ( $terms && count( $terms ) > 1 ) {
                if ( reset( $terms )->parent == 0 ) {

                    $keys = array_keys( $terms );
                    $term = $terms[$keys[1]]->slug;

                    if ( $terms[ $keys[0] ]->term_id == $terms[ $keys[1] ]->parent ) {
                        $term = keha_get_taxonomy_parents( $terms[ $keys[1] ]->parent, $taxonomy, false, '/', true ) . $term;
                    }

                } else {

                    $keys = array_keys( $terms );
                    $term = $terms[ $keys[0] ]->slug;

                    if ( $terms[ $keys[1] ]->term_id == $terms[ $keys[0] ]->parent ) {
                        $term = keha_get_taxonomy_parents( $terms[ $keys[0] ]->parent, $taxonomy, false, '/', true ) . $term;
                    }

                }

            } elseif ( $terms ) {

                $term_obj = array_shift( $terms );
                $term = $term_obj->slug;

                if( isset( $term_obj->parent ) and $term_obj->parent != 0 ) {
                    $term = keha_get_taxonomy_parents( $term_obj->parent, $taxonomy, false, '/', true ) . $term;
                }
            }

            if( isset( $term ) ) {
                $permalink = str_replace( "%$taxonomy%", $term, $permalink );
            }
        }
    }
    return $permalink;
}
add_filter('post_type_link', 'keha_post_type_link', 10, 3);

function keha_term_link( $termlink, $term, $taxonomy ) {

    $taxonomy = get_taxonomy( $taxonomy );

    if( $taxonomy->_builtin )
        return $termlink;

    if( empty( $taxonomy ) )
        return $termlink;

    $wp_home = rtrim( home_url(), '/' );

    $post_type = $taxonomy->object_type[0];
    $slug = get_post_type_object( $post_type )->rewrite['slug'];
    $with_front = get_post_type_object( $post_type )->rewrite['with_front'];

    $str = rtrim( preg_replace( "/%[a-z_]*%/", "" , get_option( "permalink_structure" ) ) ,'/' );
    $termlink = str_replace( $str . "/", "/", $termlink );

    if( $with_front === false ) {
        $str = "";
    }
    $slug = $str . "/" . $slug;

    $termlink = str_replace( $wp_home, $wp_home . $slug, $termlink );
    $termlink = str_replace( $term->slug.'/', keha_get_taxonomy_parents( $term->term_id, $taxonomy->name, false, '/', true ), $termlink );

    return $termlink;
}
add_filter( 'term_link', 'keha_term_link', 10, 3 );

function keha_get_taxonomy_parents( $id, $taxonomy = 'category', $link = false, $separator = '/', $nicename = false, $visited = array() ) {
    $chain = '';
    $parent = get_term( $id, $taxonomy, OBJECT, 'raw');
    if ( is_wp_error( $parent ) ) {
        return $parent;
    }

    if ( $nicename ){
        $name = $parent->slug;
    }else {
        $name = $parent->name;
    }

    if ( $parent->parent && ( $parent->parent != $parent->term_id ) && !in_array( $parent->parent, $visited ) ) {
        $visited[] = $parent->parent;
        $chain .= keha_get_taxonomy_parents( $parent->parent, $taxonomy, $link, $separator, $nicename, $visited );
    }

    if ( $link ) {
        $chain .= '<a href="' . get_term_link( $parent->term_id, $taxonomy ) . '" title="' . esc_attr( sprintf( __( "View all posts in %s" ), $parent->name ) ) . '">'.$name.'</a>' . $separator;
    }else {
        $chain .= $name.$separator;
    }
    return $chain;
}

function keha_register_photo_tax_album() {

    $labels = array(
        'name'              => _x( 'Albums', 'taxonomy general name', 'blank' ),
        'singular_name'     => _x( 'Album', 'taxonomy singular name', 'blank' ),
        'search_items'      => __( 'Search Albums', 'blank' ),
        'all_items'         => __( 'All Albums', 'blank' ),
        'parent_item'       => __( 'Parent Album', 'blank' ),
        'parent_item_colon' => __( 'Parent Album:', 'blank' ),
        'edit_item'         => __( 'Edit Album', 'blank' ),
        'update_item'       => __( 'Update Album', 'blank' ),
        'add_new_item'      => __( 'Add New Album', 'blank' ),
        'new_item_name'     => __( 'New Album Name', 'blank' ),
        'menu_name'         => __( 'Albums', 'blank' ),
    );

    $rewrite = array(
        'slug' => 'album',
        'with_front' => false,
        'hierarchical' => true,
    );

    $args = array(
        'hierarchical' => true,
        'labels'       => $labels,
        'show_ui'      => true,
        'query_var'    => true,
        'rewrite'      => $rewrite
    );

    register_taxonomy( 'album', array('photo'), $args );
}
add_action( 'init', 'keha_register_photo_tax_album' );

function keha_register_cpt_photo() {

    $labels = array(
        'name'               => __( 'Photos', 'blank' ),
        'singular_name'      => _x( 'Photo', 'Photo post type singular', 'blank' ),
        'add_new'            => __( 'Add New', 'blank' ),
        'add_new_item'       => __( 'Add New Photo', 'blank' ),
        'edit_item'          => __( 'Edit Photo', 'blank' ),
        'new_item'           => __( 'New Photo', 'blank' ),
        'all_items'          => __( 'All Photos', 'blank' ),
        'view_item'          => __( 'View Photo', 'blank' ),
        'search_items'       => __( 'Search Photos', 'blank' ),
        'not_found'          => __( 'No photos found', 'blank' ),
        'not_found_in_trash' => __( 'No photos found in Trash', 'blank' ),
        'parent_item_colon'  => '',
        'menu_name'          => __( 'Photos', 'blank' )
    );

    $args = array(
        'labels'               => $labels,
        'exclude_from_search'  => false,
        'publicly_queryable'   => true,
        'show_ui'              => true,
        'show_in_nav_menus'    => true,
        'show_in_menu'         => true,
        'show_in_admin_bar'    => true,
        'menu_position'        => 20,
        'menu_icon'            => null,
        'capability_type'      => 'post',
        'hierarchical'         => false,
        'public'               => true,
        'supports'             => array( 'title', 'editor', 'thumbnail' ),
        'taxonomies'           => array( 'album' ),
        'rewrite'              => array( 'slug' =>'photos/%album%' ),
        'has_archive'          => true,
        'query_var'            => true,
        'can_export'           => true
    );

    register_post_type( 'photo', $args );
}
add_action( 'init', 'keha_register_cpt_photo' );