/**
 * Filters Users based on Gender. Make sure only users of opposite genders are visible.
 */
class BuddyDev_Gender_Based_Member_Filter {

    /**
     * Boot
     *
     * @return BuddyDev_Gender_Based_Member_Filter
     */
    public static function boot() {
        $self = new self();
        $self->setup();

        return $self;
    }

    /**
     * Setup hooks.
     */
    private function setup() {
        add_action( 'bp_pre_user_query', array( $this, 'exclude_same_gender_users' ), 9 );

        add_action( 'bp_template_redirect', array( $this, 'check_access' ), 10, 2 );
    }

    // Modifies members loop args to filter out users of same gender.
    public function exclude_same_gender_users( BP_User_Query $query ) {
        // do not filter if user is not logged in, or is super admin or we are inside dashboard.
        if ( ! is_user_logged_in() || is_super_admin() || ( is_admin() && ! defined( 'DOING_AJAX' ) ) ) {
            return;
        }

        $opposite_gender  = $this->get_opposite_gender( bp_loggedin_user_id() );
        if ( $opposite_gender ) {
            $query->query_vars['xprofile_query'] = array(
                array(
                    'field'   => bp_get_xprofile_gender_type_field_id(), // field id or name.
                    'value'   => $opposite_gender,
                    'compare' => '=',
                ),
            );
        }
    }

    // Restricts access to user profile.
    // Only allows profile owner, user of opposite gender or site admins to view.
    public function check_access() {
        if ( ! is_user_logged_in() || ! bp_is_user() || bp_is_my_profile() || is_super_admin() ) {
            return;
        }

        $user_gender           = $this->get_user_gender( bp_loggedin_user_id() );
        $displayed_user_gender = $this->get_user_gender( bp_displayed_user_id() );

        // do not allow access for same gender.
        if ( $displayed_user_gender === $user_gender ) {
            bp_core_add_message( __( 'Access denied.', 'yym-helper' ) );
            bp_core_redirect( bp_loggedin_user_domain() );
        }
    }

    // Get user gender
    private function get_user_gender( $user_id ) {
        return xprofile_get_field_data( bp_get_xprofile_gender_type_field_id(), $user_id );
    }

    // Finds the opposite gender
    private function get_opposite_gender( $user_id ) {

        $user_gender = $this->get_user_gender( $user_id );

        if ( empty( $user_gender ) ) {
            return null;
        }

        if ( $user_gender === 'his_Male' ) {
            return 'her_Female';
        } elseif ( $user_gender === 'her_Female' ) {
            return 'his_Male';
        }

        return null;
    }

}

BuddyDev_Gender_Based_Member_Filter::boot();