Error handling inside stored procedure

create proc _Err_Sp
@Emp_Code char(5),
@Name_Type char(1)= 'O',   ----'O'- organization; 'P' - person
@Client_Name varchar(120),  -- for person "Last Name"
@First_Name varchar(20) = '',
@Middle_Name varchar(20) = '',
@Currency char(3) ='USD'

as

/*
This procedure created entry in the Name table for client with indication if it's person or organization.
Passing parameters include Employee code, insert info,type 
Validation have to be done on employee code and type
*/declare@Emp_ID int,
@Full_Client_Name char(120),
@Client_Name_Rept char(40),
@ErrNum int, 
@RowCount int,
@myerror varchar (50),
@err_emp int ,
@err_type int

set @err_emp =30001
set @err_type = 30002
set @MyError =""

set nocount on

IF @@TRANCOUNT=0
BEGIN TRAN

select @Emp_ID =  EMP_ID from tbl_PERSNL where EMPLOYEE_CODE = @Emp_Code
select @RowCount = @@ROWCOUNT, @ErrNum = @@ERROR
if   @ErrNum <> 0 GOTO myerror

IF @RowCount = 0 
begin
set @myerror = "Employee Code is Invalid "
set @ErrNum =@err_emp
GOTO myerror
end

if @Name_Type ='P' 
   BEGIN
select @Full_Client_Name =rtrim( rtrim(@Client_Name)+ ','+rtrim(coalesce(@First_Name,''))+ ' ' +rtrim(coalesce(@Middle_Name,'')))
select @Client_Name_Rept = left(@Full_Client_Name,40)

insert into TBL_NAME
(MAIN_NAME,LAST_NAME,FIRST_NAME,MIDDLE_NAME,
LANGUAGE_CODE,CURRENCY)
values ( @Full_Client_Name,@Client_Name,@First_Name,@Middle_Name,'EN',@Currency)
set @ErrNum = @@ERROR
if   @ErrNum <> 0 GOTO myerror

   END
else if @Name_Type ='O'
   BEGIN
select @Client_Name_Rept = left(@Client_Name,40)
insert into TBL_NAME
(MAIN_NAME,NAME_REPT,LANGUAGE_CODE,CURRENCY)
values (@Client_Name,@Client_Name_Rept,'EN',@Currency)
set @ErrNum = @@ERROR
if   @ErrNum <> 0 GOTO myerror

   END
ELSE
   BEGIN
set @myerror = "Name Type is Invalid "
set @ErrNum =@err_type
GOTO myerror
   END

COMMIT TRAN 

set nocount off
RETURN 0

myerror:
BEGIN

if @@trancount<>0 
begin
 ROLLBACK TRAN
select 'Rolling Back Client'
end
IF len(ltrim(rtrim(@myerror)))= 0
/* If it's system error */SELECT @myerror = (SELECT  description FROM  master..sysmessages WHERE error = @ErrNum)

raiserror @errnum @myerror

set nocount off
RETURN @ErrNum
END