Help needed, zongshen wont fire, good spark&fuel

[b44]

Ok gents totally didn't expect this,here lies the problem
Question is do i just get piston kit? Or piston & bore kit?
Also there is good chunks of piston missing fk knows where in the crankcase?
Or is complete engine replacement better option?
Any suggestions welcome gentlemen, bearing in mind bike only cost $300 aus
Im actually not even pissed off, more wtf?
Any ideas how this could of happen on such a new bike?
Is it the obvious & no oil?
Thanks to all that had all the suggestions
Cheers