General aviation pilot reported a near miss with another aircraft while entering the airport traffic pattern. The pilot maneuvered to avoid the other aircraft in response to a clearance from the Tower; then continued for a safe landing.

Narrative

I was returning to TCL; from ZZZ. BHM Approach asked which runway I would prefer as Runway 22 was being used; winds were 170/08. I requested Runway 12 as it was closer to the FBO; and was told to enter a left downwind for Runway 12 with the airport in sight. I was handed off to TCL Tower about 3 miles E/NE of the field. I checked in with the Tower Controller and announced I was entering the left downwind for Runway 12. Tower Controller acknowledged this; then a minute later asked me to call abeam the centerline for Runway 22 as he had Aircraft Y on a right base for Runway 22. At that time I was nearly abeam the centerline for Runway 22 and announced I was almost there now. The Controller asked if I had Aircraft Y in sight; which I replied 'No'. He then asked Aircraft Y if he had me in sight. He replied 'no' also. The Controller seemed to panic and loudly instructed me to turn right (to do a 360 deg. turn; I believe he said). I initiated an immediate turn looking for the traffic as the Controller instructed Aircraft Y to turn also. About 20 deg. Into the turn Heading (HDG 320) I saw Aircraft Y just below me; estimated at 200 ft. The Controller had a long pause and both of us announced we had visual on each other. We both continued for safe landings on our assigned runways. No other comments were made by the Controller to either of us. I realize TCL Tower has no radar; but why Approach Control or the Tower would allow my aircraft to approach the airport in the same airspace as Aircraft Y who was performing numerous practice pattern landings is unacceptable. One of us should have been vectored to stay clear and worked into the pattern like every other Tower controlled airport does.