I would be very happy in my job if I earned a large salary
I will be very happy in my job if I earn a large salary
I would be very happy if I earn a large salary
I guess the first sentence is subjunctive mood, indicating I do not earn a large salary at the moment while the second is first conditional talking about a general sentiment. What about the third one? Is it correct? And if so, what is the difference between the second one and the third one. Does it express the same meaning simply less definitely?
Edit: fixed an elemtentary mistake and expand the question to include a third option.