-- A tenant clock is the short commit barrier for revision admission. Semantic
-- writers update it in their own transaction, after their entity row change.
CREATE TABLE tenant_render_generation (
    tenant_id UUID PRIMARY KEY REFERENCES tenant(id) ON DELETE CASCADE,
    generation BIGINT NOT NULL DEFAULT 1
);
INSERT INTO tenant_render_generation(tenant_id, generation)
SELECT id, 1 FROM tenant;

CREATE SEQUENCE module_snapshot_version_seq AS BIGINT;
ALTER TABLE module_prefix_snapshot
    ADD COLUMN snapshot_version BIGINT NOT NULL DEFAULT nextval('module_snapshot_version_seq');

CREATE TABLE render_revision_manifest (
    revision_id UUID PRIMARY KEY REFERENCES config_revision(id) ON DELETE CASCADE,
    tenant_id UUID NOT NULL REFERENCES tenant(id) ON DELETE CASCADE,
    config_generation BIGINT NOT NULL,
    manifest_json JSONB NOT NULL
);
CREATE INDEX render_revision_manifest_tenant ON render_revision_manifest(tenant_id, revision_id);

CREATE FUNCTION render_bump_tenant_generation(p_tenant UUID) RETURNS void
LANGUAGE plpgsql AS $$
BEGIN
    IF p_tenant IS NULL THEN RETURN; END IF;
    INSERT INTO tenant_render_generation(tenant_id, generation)
    VALUES (p_tenant, 2)
    ON CONFLICT (tenant_id) DO UPDATE
      SET generation = tenant_render_generation.generation + 1;
END;
$$;

CREATE FUNCTION render_bump_module_generation(p_module UUID) RETURNS void
LANGUAGE plpgsql AS $$
DECLARE v_tenant UUID;
BEGIN
    IF p_module IS NULL THEN RETURN; END IF;
    SELECT tenant_id INTO v_tenant FROM module WHERE id = p_module;
    PERFORM render_bump_tenant_generation(v_tenant);
END;
$$;

CREATE FUNCTION render_tenant_created() RETURNS trigger
LANGUAGE plpgsql AS $$
BEGIN
    INSERT INTO tenant_render_generation(tenant_id, generation) VALUES(NEW.id, 1);
    RETURN NEW;
END;
$$;
CREATE TRIGGER tenant_render_created AFTER INSERT ON tenant
FOR EACH ROW EXECUTE FUNCTION render_tenant_created();

CREATE FUNCTION render_semantic_change() RETURNS trigger
LANGUAGE plpgsql AS $$
DECLARE v_old JSONB; v_new JSONB;
        v_old_tenant UUID; v_new_tenant UUID;
        v_old_module UUID; v_new_module UUID;
BEGIN
    IF TG_OP = 'UPDATE' THEN
        v_old := to_jsonb(OLD);
        v_new := to_jsonb(NEW);
        IF TG_TABLE_NAME = 'module' THEN
            v_old := v_old - ARRAY['input_hash','last_refreshed_at','updated_at'];
            v_new := v_new - ARRAY['input_hash','last_refreshed_at','updated_at'];
        ELSIF TG_TABLE_NAME = 'module_cdn_source' THEN
            v_old := v_old - ARRAY['etag','last_refreshed_at','updated_at'];
            v_new := v_new - ARRAY['etag','last_refreshed_at','updated_at'];
        ELSIF TG_TABLE_NAME = 'module_as_entry' THEN
            v_old := v_old - ARRAY['asn_name','prefix_count','asn_resolved_at','updated_at'];
            v_new := v_new - ARRAY['asn_name','prefix_count','asn_resolved_at','updated_at'];
        ELSIF TG_TABLE_NAME = 'module_domain_entry' THEN
            v_old := v_old - ARRAY['resolve_meta','updated_at'];
            v_new := v_new - ARRAY['resolve_meta','updated_at'];
        ELSIF TG_TABLE_NAME = 'bgp_peer' THEN
            v_old := v_old - ARRAY['meta_json','updated_at'];
            v_new := v_new - ARRAY['meta_json','updated_at'];
        ELSIF TG_TABLE_NAME = 'bgp_community' THEN
            v_old := v_old - ARRAY['title','updated_at'];
            v_new := v_new - ARRAY['title','updated_at'];
        ELSIF TG_TABLE_NAME = 'bgp_speaker' THEN
            v_old := jsonb_build_object('node_ipv4',OLD.meta_json->>'node_ipv4',
              'bird_bgp_source_ipv4',OLD.meta_json->>'bird_bgp_source_ipv4',
              'bird_bgp_source_ipv6',OLD.meta_json->>'bird_bgp_source_ipv6');
            v_new := jsonb_build_object('node_ipv4',NEW.meta_json->>'node_ipv4',
              'bird_bgp_source_ipv4',NEW.meta_json->>'bird_bgp_source_ipv4',
              'bird_bgp_source_ipv6',NEW.meta_json->>'bird_bgp_source_ipv6');
        ELSE
            v_old := v_old - 'updated_at';
            v_new := v_new - 'updated_at';
        END IF;
        IF v_old = v_new THEN RETURN NEW; END IF;
    END IF;
    IF TG_TABLE_NAME IN ('module','doh_profile','bgp_peer','bgp_community','bgp_speaker','global_settings') THEN
        IF TG_OP = 'INSERT' THEN v_new_tenant := NEW.tenant_id;
        ELSIF TG_OP = 'DELETE' THEN v_old_tenant := OLD.tenant_id;
        ELSE v_old_tenant := OLD.tenant_id; v_new_tenant := NEW.tenant_id; END IF;
    ELSIF TG_TABLE_NAME IN ('module_cdn_source','module_domain_entry','module_as_entry','module_ip_range_entry','module_doh_profile') THEN
        IF TG_OP = 'INSERT' THEN v_new_module := NEW.module_id;
        ELSIF TG_OP = 'DELETE' THEN v_old_module := OLD.module_id;
        ELSE v_old_module := OLD.module_id; v_new_module := NEW.module_id; END IF;
    ELSIF TG_TABLE_NAME = 'module_prefix_snapshot' THEN
        IF TG_OP = 'INSERT' THEN v_new_tenant := NEW.tenant_id;
        ELSIF TG_OP = 'DELETE' THEN v_old_tenant := OLD.tenant_id;
        ELSE v_old_tenant := OLD.tenant_id; v_new_tenant := NEW.tenant_id; END IF;
    END IF;
    IF v_old_module IS NOT NULL THEN PERFORM render_bump_module_generation(v_old_module); END IF;
    IF v_new_module IS NOT NULL AND v_new_module IS DISTINCT FROM v_old_module THEN
        PERFORM render_bump_module_generation(v_new_module);
    END IF;
    IF v_old_tenant IS NOT NULL THEN PERFORM render_bump_tenant_generation(v_old_tenant); END IF;
    IF v_new_tenant IS NOT NULL AND v_new_tenant IS DISTINCT FROM v_old_tenant THEN
        PERFORM render_bump_tenant_generation(v_new_tenant);
    END IF;
    IF TG_OP = 'DELETE' THEN RETURN OLD; END IF;
    RETURN NEW;
END;
$$;

CREATE FUNCTION render_snapshot_version() RETURNS trigger
LANGUAGE plpgsql AS $$
BEGIN
    NEW.snapshot_version := nextval('module_snapshot_version_seq');
    RETURN NEW;
END;
$$;
CREATE TRIGGER module_snapshot_version BEFORE INSERT OR UPDATE ON module_prefix_snapshot
FOR EACH ROW EXECUTE FUNCTION render_snapshot_version();

CREATE TRIGGER render_module_changed AFTER INSERT OR UPDATE OR DELETE ON module
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_cdn_source_changed AFTER INSERT OR UPDATE OR DELETE ON module_cdn_source
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_as_entry_changed AFTER INSERT OR UPDATE OR DELETE ON module_as_entry
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_domain_entry_changed AFTER INSERT OR UPDATE OR DELETE ON module_domain_entry
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_ip_range_entry_changed AFTER INSERT OR UPDATE OR DELETE ON module_ip_range_entry
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_doh_profile_changed AFTER INSERT OR UPDATE OR DELETE ON doh_profile
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_module_doh_changed AFTER INSERT OR UPDATE OR DELETE ON module_doh_profile
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_peer_changed AFTER INSERT OR UPDATE OR DELETE ON bgp_peer
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_community_changed AFTER INSERT OR UPDATE OR DELETE ON bgp_community
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_settings_changed AFTER INSERT OR UPDATE OR DELETE ON global_settings
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_speaker_changed AFTER INSERT OR UPDATE OR DELETE ON bgp_speaker
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();
CREATE TRIGGER render_snapshot_changed AFTER INSERT OR UPDATE OR DELETE ON module_prefix_snapshot
FOR EACH ROW EXECUTE FUNCTION render_semantic_change();