Property Hive - [properties] shortcode with fallback

snippet.php

add_shortcode( 'properties_with_fallback', 'ph_properties_with_fallback' );

function ph_properties_with_fallback( $atts ) {

    $atts = shortcode_atts(
        array(
            'primary_atts'     => '',
            'fallback_atts'    => '',
            'fallback_message' => '',
        ),
        $atts
    );

    // Primary PropertyHive shortcode
    $primary_shortcode = '[properties ' . $atts['primary_atts'] . ']';
    $primary_output    = do_shortcode( $primary_shortcode );

    // Look for no-results-message string
    if ( strpos( $primary_output, 'no-results-message' ) !== false ) {

        $output = '';

        // Optional fallback message
        if ( ! empty( $atts['fallback_message'] ) ) {
            $output .= '<div class="properties-fallback-message">';
            $output .= wp_kses_post( wpautop( $atts['fallback_message'] ) );
            $output .= '</div>';
        }

        // Fallback PropertyHive shortcode
        $fallback_shortcode = '[properties ' . $atts['fallback_atts'] . ']';
        $output .= do_shortcode( $fallback_shortcode );

        return $output;
    }

    return $primary_output;
}

/* 
 * example usage:
 * 
[properties_with_fallback 
primary_atts="department='residential-sales' address_keyword='Edinburgh'" 
fallback_atts="department='residential-sales' address_keyword='Glasgow'"
fallback_message="No results available for X, here are some other properties"
]

 * /