GA pilot reported landing on the runway with another aircraft still on departure roll.

Narrative

I entered the pattern at SMD to land on runway 31. Upon entering the downwind; I observed two aircraft on sitting on opposite sides of the approach end of runway 31. Shortly after; one of the aircraft announced it was departing runway 31; at which time he taxied onto the runway and promptly departed.After announcing each segment of both my downwind and base legs; I announced my turn onto final approach for runway 31. It was at that time that Aircraft Y taxied from it's parked position at the taxiway / runway intersection and onto the runway 31 (Note: I did not hear a radio call from the Aircraft Y at the time they entered the runway either). At this point in the flight; I had my aircraft in it's final configuration for landing.Believing that the pilot was aware of my announcement to final; I assumed that they would be departing quickly. However; the aircraft lined up with the runway centerline and parked. I called on the radio 'Aircraft positioned on the approach end of 31; get the [expletive] off the runway'. The response from the now parked aircraft was 'You can go around'.I began to reconfigure my aircraft to go-around; when the aircraft on the runway decided he was going to depart. In order to avoid a situation where I would be over flying the runway and have a departing aircraft flying up under me; I reduced power completely; pulled in 40 degrees of flaps (typically land with only 30deg flaps) to further reduce my decent speed; and landed an estimated 600 feet behind the now departing aircraft.My purpose for filing this report is two-fold: #1 I should have not used the word '[expletive]' in my communication to the pilot parked on the runway. I knowingly admit it was not the proper vernacular that I should have used; and I will refrain from using it in future radio communications.#2 I consider the pilot's actions to have created an unsafe condition for both aircraft. I also feel that his acknowledgement of my position and apparent lack of care; signified by his arrogant response of 'You can go around'; to be unbecoming of a flight instructor. Especially one who had a student with him (presumed on my part); who's actions have now been observed by the student pilot.