CREATE PROCEDURE ACCOUNT_LOGIN
(
    @AccountID varchar(21),
    @Password varchar(13),
    @nRet smallint OUTPUT
)
AS
BEGIN

    DELETE FROM CURRENTUSER
    WHERE strAccountID = @AccountID

    DECLARE @cnt bigint
    DECLARE @nDays smallint
    DECLARE @pwd varchar(13)

    -- Check if account exists
    SELECT @nRet = COUNT(*)
    FROM TB_USER
    WHERE strAccountID = @AccountID

    -- Auto register account
    IF @nRet = 0
    BEGIN
        INSERT INTO TB_USER
        (
            strAccountID,
            strPasswd,
            strSocNo,
            iDays
        )
        VALUES
        (
            @AccountID,
            @Password,
            1,
            6
        )
    END

    -- Current online users
    SELECT @cnt = COUNT(*)
    FROM CURRENTUSER

    -- Premium days
    SELECT @nDays = nDays
    FROM PREMIUM_SERVICE
    WHERE strAccountID = @AccountID

    -- Server full check
    IF @cnt > 40 AND (@nDays = 0 OR @nDays IS NULL)
    BEGIN
        SET @nRet = 0
        RETURN
    END

    -- Get password
    SELECT @pwd = strPasswd
    FROM TB_USER
    WHERE strAccountID = @AccountID

    -- Account not found
    IF @pwd IS NULL
    BEGIN
        SET @nRet = 0
        RETURN
    END

    -- Password check
    IF @pwd <> @Password
    BEGIN
        SET @nRet = 0
        RETURN
    END

    -- Success
    SET @nRet = 1

END