53 reg 1.7 diesel astra cdti, Alternator or ECU problem????

First the coolant warning light on the dash came on, a few days later the ABS light came on and the speedo needle intermittently dropped to 0 then back to normal. Occasionally the power steering didn't work just after starting then was ok. Then for a couple of days the ignition (battery) warning light flickered on when driving then it stopped . Today the engine management warning light came on, I stopped the car and when I tried to start it again the battery was totally dead. Jump started it and limped home with no power steering or speedo, rev ctr etc. Any ideas anyone please?