C172 pilot reported while on final approach an aircraft was taking off from the same runway. Reporter took evasive action and was informed by Tower Controller they had entered controlled airspace without a clearance.

Narrative

On Day 0 @XA:18 I was flying into ZZZ and was under the impression the Tower was not open. Earlier during flight planning I had looked at VFR sectional which does not depict ZZZ as controlled and NOTAMS. 2 NOTAMS showed Tower was inactive and 1 showed it was active. Time for active was XB00-XC00 M-F. I was confused by this and called to verify hours with FBO at terminal. I was told this was local; not GMT times. All of this being said I was flying into ZZZ; monitoring CTAF; trying to get weather with AWOS (not working); and did listen to Tower frq. but heard nothing. My weather showed slight wind from south so i set up an approach into Runway XX. As i was descending into XX on final I saw an aircraft on runway with lights on and rolling to a turn off. I immediately took evasive action while checking traffic on my IPAD rolling right and ascended into a left downwind for Runway XY. About this time I was contacted by ATC(Tower) on CTAF questioning who is trying to enter controlled space. I immediately replied and apologized I think; and was told of my error and asked 'what are your intentions'. I said that I would like to continue left downwind for XY and land if possible. He replied;' Aircraft X cleared to land; I'll have a number for you to call when you can write it down.' As soon as I landed and got on the ramp. I called Tower back on radio and got the number. Afterwards I called but the Controller was busy so he asked that I leave my info at FBO desk which I did. A little later while taxiing out for departure on Ground the Controller and I had a few moments to discuss and he informed me he had the issue captured on tape and would file a report. I apologized again and got cleared for takeoff and departed.Biggest lesson here is that I should have tried to contact the Tower and not assume that it was inactive when I didn't hear any traffic on the frequency. I'm pretty sure I was switching back and forth between AWOS and CTAF and just didn't hear the traffic on the Tower freq. That being said I will always call up the Tower or Center prior to entering airspace going forward. I believe the fact that the Tower was temporary in past only on game days and is now open daily but not depicted on sectionals nay have made my decision making skewed.