CREATE EXTENSION IF NOT EXISTS pg_trgm;
CREATE EXTENSION IF NOT EXISTS pgcrypto;

CREATE SEQUENCE node_updates;

CREATE TABLE public."user" (
	id         serial4   NOT NULL,
	username   varchar   NOT NULL,
	"name"     varchar   NOT NULL,
	"password" varchar   NOT NULL,
	last_login timestamp DEFAULT now() NOT NULL,
	timezone   varchar   DEFAULT 'UTC'::character varying NOT NULL,
	CONSTRAINT user_pk PRIMARY KEY (id)
);

CREATE TABLE public.node (
	id                serial4      NOT NULL,
	user_id           int4         NOT NULL,
	"uuid"            bpchar(36)   DEFAULT gen_random_uuid() NOT NULL,
	parent_uuid       bpchar(36)   NULL,

	created           timestamptz  DEFAULT NOW() NOT NULL,
	updated           timestamptz  DEFAULT NOW() NOT NULL,
	deleted           timestamptz  NULL,

	created_seq       bigint       NOT NULL DEFAULT nextval('node_updates'),
	updated_seq       bigint       NOT NULL DEFAULT nextval('node_updates'),
	deleted_seq       bigint       NULL,

	"name"            varchar(256) DEFAULT ''::character varying NOT NULL,
	"content"         text         DEFAULT ''::text NOT NULL,
	content_encrypted text         DEFAULT ''::text NOT NULL,
	markdown          bool         DEFAULT false NOT NULL,

	CONSTRAINT name_length CHECK ((length(TRIM(BOTH FROM name)) > 0)),
	CONSTRAINT node_pk PRIMARY KEY (id),
	CONSTRAINT user_fk FOREIGN KEY (user_id) REFERENCES public."user"(id) ON DELETE RESTRICT ON UPDATE RESTRICT
);
CREATE UNIQUE INDEX node_uuid_idx ON public.node USING btree (uuid);
CREATE INDEX node_search_index ON public.node USING gin (name gin_trgm_ops, content gin_trgm_ops);

CREATE OR REPLACE FUNCTION node_update_timestamp()
RETURNS TRIGGER
LANGUAGE PLPGSQL
AS $$
BEGIN
	IF NEW.updated = OLD.updated THEN
		UPDATE node
		SET
			updated = NOW(),
			updated_seq = nextval('node_updates')
		WHERE
			id=NEW.id;
	END IF;
	RETURN NEW;
END;
$$;

CREATE OR REPLACE TRIGGER node_update AFTER UPDATE ON node
FOR EACH ROW
EXECUTE PROCEDURE node_update_timestamp();