CREATE TYPE HASH_TYPE AS ENUM ('SHA256');
CREATE TYPE SIGNATURE_TYPE AS ENUM ('JWS/JCS');

-- DROP TABLE IF EXISTS public.audit CASCADE;
CREATE TABLE public.audit (
    audit_id            BIGSERIAL PRIMARY KEY,
    version             SMALLINT NOT NULL,
    event_id            UUID,
    agreement_id        UUID,
    hash_type           HASH_TYPE NOT NULL,
    digest              TEXT NOT NULL,
    created             BIGINT NOT NULL,
    created_ts          TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_ts          TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx__public__audit__event_id       ON public.audit (event_id);
CREATE INDEX idx__public__audit__agreement_id   ON public.audit (agreement_id);
CREATE INDEX idx__public__audit__created        ON public.audit (created);
CREATE INDEX idx__public__audit__created_ts     ON public.audit (created_ts);
CREATE INDEX idx__public__audit__updated_ts     ON public.audit (updated_ts);
ALTER TABLE public.audit
ADD CONSTRAINT cnst__audit__event_or_agreement
CHECK (num_nonnulls(event_id, agreement_id) = 1);

-- DROP TABLE IF EXISTS public.audit_signature CASCADE;
CREATE TABLE public.audit_signature (
    signature_id        BIGSERIAL PRIMARY KEY,
    audit_id            BIGINT NOT NULL REFERENCES public.audit(audit_id),
    version             SMALLINT NOT NULL,
    id                  TEXT NOT NULL,
    signedOn            BIGINT NOT NULL,
    type                SIGNATURE_TYPE NOT NULL,
    jws                 TEXT NOT NULL,
    created_ts          TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_ts          TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX idx__public__audit_signature__id             ON public.audit_signature (id);
CREATE INDEX idx__public__audit_signature__signedOn       ON public.audit_signature (signedOn);
CREATE INDEX idx__public__audit_signature__type           ON public.audit_signature (type);
CREATE INDEX idx__public__audit_signature__created_ts     ON public.audit_signature (created_ts);
CREATE INDEX idx__public__audit_signature__updated_ts     ON public.audit_signature (updated_ts);