How to make a copy sql database in same server?

USE master
GO

-- the original database (use 'SET @DB = NULL' to disable backup)
DECLARE @DB varchar(200)
SET @DB = 'PcTopp'

-- the backup filename
DECLARE @BackupFile varchar(2000)
SET @BackupFile = 'c:\pctopp\sqlserver\backup.dat'

-- the new database name
DECLARE @TestDB varchar(200)
SET @TestDB = 'TestDB'

-- the new database files without .mdf/.ldf
DECLARE @RestoreFile varchar(2000)
SET @RestoreFile = 'c:\pctopp\sqlserver\backup'

-- ****************************************************************
--                    no change below this line
-- ****************************************************************

DECLARE @query varchar(2000)

DECLARE @DataFile varchar(2000)
SET @DataFile = @RestoreFile + '.mdf'

DECLARE @LogFile varchar(2000)
SET @LogFile = @RestoreFile + '.ldf'

IF @DB IS NOT NULL
BEGIN
    SET @query = 'BACKUP DATABASE ' + @DB + ' TO DISK = ' + QUOTENAME(@BackupFile, '''')
    EXEC (@query)
END

-- RESTORE FILELISTONLY FROM DISK = 'C:\temp\backup.dat'
-- RESTORE HEADERONLY FROM DISK = 'C:\temp\backup.dat'
-- RESTORE LABELONLY FROM DISK = 'C:\temp\backup.dat'
-- RESTORE VERIFYONLY FROM DISK = 'C:\temp\backup.dat'

IF EXISTS(SELECT * FROM sysdatabases WHERE name = @TestDB)
BEGIN
    SET @query = 'DROP DATABASE ' + @TestDB
    EXEC (@query)
END

RESTORE HEADERONLY FROM DISK = @BackupFile
DECLARE @File int
SET @File = @@ROWCOUNT

DECLARE @Data varchar(500)
DECLARE @Log varchar(500)

SET @query = 'RESTORE FILELISTONLY FROM DISK = ' + QUOTENAME(@BackupFile , '''')

CREATE TABLE #restoretemp
(
 LogicalName varchar(500),
 PhysicalName varchar(500),
 type varchar(10),
 FilegroupName varchar(200),
 size int,
 maxsize bigint
)
INSERT #restoretemp EXEC (@query)

SELECT @Data = LogicalName FROM #restoretemp WHERE type = 'D'
SELECT @Log = LogicalName FROM #restoretemp WHERE type = 'L'

PRINT @Data
PRINT @Log

TRUNCATE TABLE #restoretemp
DROP TABLE #restoretemp

IF @File > 0
BEGIN
    SET @query = 'RESTORE DATABASE ' + @TestDB + ' FROM DISK = ' + QUOTENAME(@BackupFile, '''') + 
        ' WITH MOVE ' + QUOTENAME(@Data, '''') + ' TO ' + QUOTENAME(@DataFile, '''') + ', MOVE ' +
        QUOTENAME(@Log, '''') + ' TO ' + QUOTENAME(@LogFile, '''') + ', FILE = ' + CONVERT(varchar, @File)
    EXEC (@query)
END
GO