package oracle

import (
	"strings"
	"sync"
)

var setupReserved sync.Once
var reservedWords map[string]struct{}

func isReserved(w string) bool {
	setupReserved.Do(
		func() {
			words := strings.Split(reserved, "\n")
			reservedWords = make(map[string]struct{}, len(words))
			for _, s := range words {
				reservedWords[s] = struct{}{}
			}
		},
	)
	_, ok := reservedWords[strings.ToUpper(w)]
	return ok
}

const reserved = `AGGREGATE
ACCESS
ADD
ALL
ALTER
AND
ANY
AS
ASC
AT
AUDIT
BETWEEN
BY
CHAR
CHECK
CLUSTER
COLUMN
COLUMN_VALUE
COMMENT
COMPRESS
CONNECT
CREATE
CURRENT
DATE
DECIMAL
DEFAULT
DELETE
DESC
DISTINCT
DROP
ELSE
EXCLUSIVE
EXISTS
FILE
FLOAT
FOR
FROM
GRANT
GROUP
HAVING
IDENTIFIED
IMMEDIATE
IN
INCREMENT
INDEX
INITIAL
INSERT
INTEGER
INTERSECT
INTO
IS
LEVEL
LIKE
LOCK
LONG
MAXEXTENTS
MINUS
MLSLABEL
MODE
MODIFY
NESTED_TABLE_ID
NOAUDIT
NOCOMPRESS
NOT
NOWAIT
NULL
NUMBER
OF
OFFLINE
ON
ONLINE
OPTION
OR
ORDER
PCTFREE
PRIOR
PUBLIC
RAW
RENAME
RESOURCE
REVOKE
ROW
ROWID
ROWNUM
ROWS
SELECT
SESSION
SET
SHARE
SIZE
SMALLINT
START
SUCCESSFUL
SYNONYM
SYSDATE
TABLE
THEN
TO
TRIGGER
UID
UNION
UNIQUE
UPDATE
USER
VALIDATE
VALUES
VARCHAR
VARCHAR2
VIEW
WHENEVER
WHERE
WITH`