Ford falcon ute xh not running please help

Hi I have a xh Ford falcon ute I recently went to get it registered after it had been sitting in my garage for about a year. I drove it onto a ferrie and took it to the mainland as I live on an island it had no problems when I was taking it over there but the following day after doing so it had a flat battery which is brand new and I jump started it and drove it around for about 30th mins and it was running fine then the following day it once again had a flat battery but this time after jumping it again it was running rough then it died again so I tried to jump it again but it sounded as tho it didn't have enough charge to fire but after a while it finally fired. It drove for about 5 mins but it started to run rough yet again and then stalled it's also an automatic also during the time of it running rough all the electrics in the car kept turning off and on. I tried to start it again after that but no go. I wondering what the problem could be? It has had the coil pack changed a new distributor new fan belt new sparks new leads new oil new oil filter the timing is correct and also a new battery. Anyone able to help please?