-- Add procedure to decimate old nav data
--
-- New schema version: 0.6.6
--
-- ATTENTION:
--
-- ENSURE YOU HAVE BACKED UP THE DATABASE BEFORE RUNNING THIS SCRIPT.
--
--
-- NOTE: This upgrade affects the public schema only.
-- NOTE: Each application starts a transaction, which must be committed
-- or rolled back.
--
-- This adds a last_project_update(pid) function. It takes a project ID
-- and returns the last known timestamp from that project. Timestamps
-- are derived from multiple sources:
--
-- - raw_shots table
-- - final_shots table
-- - events_log_full table
-- - info table where key = 'qc'
-- - files table, from the hashes (which contain the file's mtime)
-- - project configuration, looking for an _updatedOn property
--
-- To apply, run as the dougal user:
--
-- psql <<EOF
-- \i $THIS_FILE
-- COMMIT;
-- EOF
--
-- NOTE: It can be applied multiple times without ill effect.
--

BEGIN;

CREATE OR REPLACE PROCEDURE pg_temp.show_notice (notice text) AS $$
BEGIN
	RAISE NOTICE '%', notice;
END;
$$ LANGUAGE plpgsql;

CREATE OR REPLACE PROCEDURE pg_temp.upgrade_database () AS $outer$
BEGIN

	RAISE NOTICE 'Updating schema %', 'public';
	SET search_path TO public;

	-- BEGIN

	CREATE OR REPLACE FUNCTION public.last_project_update(p_pid text)
	RETURNS timestamp with time zone
	LANGUAGE plpgsql
	AS $function$
	DECLARE
		v_last_ts timestamptz := NULL;
		v_current_ts timestamptz;
		v_current_str text;
		v_current_unix numeric;
		v_sid_rec record;
	BEGIN
		-- From raw_shots, final_shots, info, and files
		FOR v_sid_rec IN SELECT schema FROM public.projects WHERE pid = p_pid
		LOOP
			-- From raw_shots
			EXECUTE 'SELECT max(tstamp) FROM ' || v_sid_rec.schema || '.raw_shots' INTO v_current_ts;
			IF v_current_ts > v_last_ts OR v_last_ts IS NULL THEN
				v_last_ts := v_current_ts;
			END IF;

			-- From final_shots
			EXECUTE 'SELECT max(tstamp) FROM ' || v_sid_rec.schema || '.final_shots' INTO v_current_ts;
			IF v_current_ts > v_last_ts OR v_last_ts IS NULL THEN
				v_last_ts := v_current_ts;
			END IF;

			-- From info where key = 'qc'
			EXECUTE 'SELECT value->>''updatedOn'' FROM ' || v_sid_rec.schema || '.info WHERE key = ''qc''' INTO v_current_str;
			IF v_current_str IS NOT NULL THEN
				v_current_ts := v_current_str::timestamptz;
				IF v_current_ts > v_last_ts OR v_last_ts IS NULL THEN
					v_last_ts := v_current_ts;
				END IF;
			END IF;

			-- From files hash second part, only for valid colon-separated hashes
			EXECUTE 'SELECT max( split_part(hash, '':'', 2)::numeric ) FROM ' || v_sid_rec.schema || '.files WHERE hash ~ ''^[0-9]+:[0-9]+\\.[0-9]+:[0-9]+\\.[0-9]+:[0-9a-f]+$''' INTO v_current_unix;
			IF v_current_unix IS NOT NULL THEN
				v_current_ts := to_timestamp(v_current_unix);
				IF v_current_ts > v_last_ts OR v_last_ts IS NULL THEN
					v_last_ts := v_current_ts;
				END IF;
			END IF;

			-- From event_log_full
			EXECUTE 'SELECT max(tstamp) FROM ' || v_sid_rec.schema || '.event_log_full' INTO v_current_ts;
			IF v_current_ts > v_last_ts OR v_last_ts IS NULL THEN
				v_last_ts := v_current_ts;
			END IF;
		END LOOP;

		-- From projects.meta->_updatedOn
		SELECT (meta->>'_updatedOn')::timestamptz FROM public.projects WHERE pid = p_pid INTO v_current_ts;
		IF v_current_ts > v_last_ts OR v_last_ts IS NULL THEN
			v_last_ts := v_current_ts;
		END IF;

		RETURN v_last_ts;
	END;
	$function$;

	-- END

END;
$outer$ LANGUAGE plpgsql;

CREATE OR REPLACE PROCEDURE pg_temp.upgrade () AS $outer$
DECLARE
	row RECORD;
	current_db_version TEXT;
BEGIN

	SELECT value->>'db_schema' INTO current_db_version FROM public.info WHERE key = 'version';

	IF current_db_version >= '0.6.6' THEN
		RAISE EXCEPTION
			USING MESSAGE='Patch already applied';
	END IF;

	IF current_db_version != '0.6.5' THEN
		RAISE EXCEPTION
			USING MESSAGE='Invalid database version: ' || current_db_version,
				HINT='Ensure all previous patches have been applied.';
	END IF;

	CALL pg_temp.upgrade_database();
END;
$outer$ LANGUAGE plpgsql;

CALL pg_temp.upgrade();

CALL pg_temp.show_notice('Cleaning up');
DROP PROCEDURE pg_temp.upgrade_database ();
DROP PROCEDURE pg_temp.upgrade ();

CALL pg_temp.show_notice('Updating db_schema version');
INSERT INTO public.info VALUES ('version', '{"db_schema": "0.6.6"}')
ON CONFLICT (key) DO UPDATE
	SET value = public.info.value || '{"db_schema": "0.6.6"}' WHERE public.info.key = 'version';


CALL pg_temp.show_notice('All done. You may now run "COMMIT;" to persist the changes');
DROP PROCEDURE pg_temp.show_notice (notice text);

--
--NOTE Run `COMMIT;` now if all went well
--