Extended Tourist Visa

I am currently in Mauritius on an extended tourist visa (180 days). I will leave the island in December, 2 days before expiration of my visa. I plan to come back in April 2014 for my friend's wedding. Can anyone tell me if I will be allowed to enter? I heard that the 180 days count per calendar year. However, I also heard that one needs to wait 6 months before re-entering. Which information is correct? Thx!

The clock starts at Zero on january 1st , 2014 if you are leaving in December .

I have also been trying to find specific details on the tourist visas. For example, is it 60 or 90 days that you get when you come to the airport?

Since I must have a return ticket I dont want to reserve a return ticket 2 months after arrival if I'm actually allowed to stay for three months.