If the engine is not turning over when you turn the key then it is either power or starter motor.
The fact that it started after a jump start suggests the starter motor is ok, although they first give intermittent problems when they start to fail, so you cant rule it out.
Do you have a multimeter? Voltage at the battery should be 10+ volts with engine off, and 13.5v with engine on. If you're not getting 13.5v with engine on then you have an alternator problem.
If it's the battery I would expect to see ABS and VDC failure messages, which was what our 147 did when the battery went.