2006 Vauxhall Vivaro engine won't crank

So I brought this vivaro and they said the crankshaft bearing has gone, so I replaced the crankshaft sensor, but the engine won't turn over, so I've tried bump starting and almost ripped off the front end, so put a spanner on bottom pulley and turns both ways till a certain point and won't move.
Won't start with key won't even intertane it, I've got it a couple time to turn over by key but sounds like battery's dead recharged battery and still nothing even though everything's a lot brighter (lights and stuff)
Any ideas ?