How long after bankruptcy shall I wait to apply to refinance my mortgage?

I filed for bankruptcy in 2004 and I have been paying on it for so long now that I have a chance to pay it on out. I have about a year left to go if I don’t pay it on out. I want to refinance my house. If I pay my bankruptcy and my case is discharged, how long shall I wait before applying for a loan to refinance my home?