Building Join Script For a Given Query Dynamically?

Hi all,
I'm developing a Visual Query Builder (But Currently only for SqlServer) as the same as EnterPrise Manager'Query Builder of Sql Server 2000.
But i have problem to Creating and building Script for Join Section.in the other word i have all information about joins that USER has made visually for a query between tables for example Every Join Object contains the following info:

Start Table ---> Left Table'name of Join
End Table ---> Right Table'name of join

Join Type ---> Inner ,Left,Outer,....
Join Operator ---> Logical Operators like < > <> <=,...

Now, Imagine we have three,four or more...Link info as above,How should i Attach these Joins's information to gether to achieve a JOIN script.i need an algorithm for this.I tried to follow the lead of Sql-Server Query Builder But i mixed up because some times i can't guess it's method Can you help me?

Thanks in advance.
Best Regards.