Transparent Column Encryption with Empty string about pgsodium HOT 2 OPEN

CREATE OR REPLACE FUNCTION public.emails_encrypt_secret_summary()
 RETURNS trigger
 LANGUAGE plpgsql
 SECURITY DEFINER
AS $function$
BEGIN
    -- Encrypt the token if it's not null and key_id is not null
    NEW.summary := CASE 
        WHEN NEW.summary IS NULL THEN 
            NULL
        -- When empty string, save empty string
        WHEN NEW.summary = '' THEN
            ''
        ELSE
            CASE 
                WHEN NEW.key_id IS NULL THEN 
                    NULL 
                ELSE 
                    pg_catalog.encode(
                        pgsodium.crypto_aead_det_encrypt(
                            pg_catalog.convert_to(NEW.summary, 'utf8'),
                            pg_catalog.convert_to(('')::text, 'utf8'),
                            NEW.key_id::uuid,
                            NULL
                        ),
                        'base64'
                    ) 
            END 
    END;
  
    RETURN NEW;
END;
$function$;

DROP VIEW IF EXISTS public.decrypted_emails;
CREATE OR REPLACE VIEW public.decrypted_emails AS
 SELECT emails.id,
    emails.user_id,
    emails.body,
    emails.summary,
        CASE
            WHEN emails.summary IS NULL THEN NULL::text
            WHEN emails.summary = '' THEN ''
            ELSE
            CASE
                WHEN emails.key_id IS NULL THEN NULL::text
                ELSE convert_from(pgsodium.crypto_aead_det_decrypt(decode(emails.summary, 'base64'::text), convert_to(''::text, 'utf8'::name), emails.key_id, NULL::bytea), 'utf8'::name)
            END
        END AS decrypted_summary,

CREATE OR REPLACE FUNCTION public.emails_encrypt_secret_summary()
 RETURNS trigger
 LANGUAGE plpgsql
 SECURITY DEFINER
AS $function$
BEGIN
    -- Check if key_id is not already set, else set it to user's key_id
    IF NEW.key_id IS NULL THEN
        NEW.key_id := (
            SELECT key_id 
            FROM user_preferences 
            WHERE user_preferences.user_id = NEW.user_id
        );
    END IF;

    -- Encrypt the token if it's not null and key_id is not null
    NEW.summary := CASE 
        WHEN NEW.summary IS NULL OR NEW.summary = '' THEN 
            NULL
        ELSE
            CASE 
                WHEN NEW.key_id IS NULL THEN 
                    NULL 
                ELSE 
                    pg_catalog.encode(
                        pgsodium.crypto_aead_det_encrypt(
                            pg_catalog.convert_to(NEW.summary, 'utf8'),
                            pg_catalog.convert_to(('')::text, 'utf8'),
                            NEW.key_id::uuid,
                            NULL
                        ),
                        'base64'
                    ) 
            END 
    END;
  
    RETURN NEW;
END;
$function$;