I've got a ton of macros like this, i get this feeling like it could get shortened a fair bit, can someone with a bit more experience with macros help me out please?

This one in particular does
1. Cast drain life on hostile target i am targeting, if i'm not already casting drain life
Cast drain life on hostile target the focus is targeting, if i'm not already casting drain life
2. Alt modifier - Cast drain mana regardless of whether or not i'm channelling
3. Ctrl modifier - Cast drain soul (rank 1) regardless of whether or not i'm channelling

Code:
#showtooltip
/cast [target=player-target,nomod,harm,nochanneling: Drain Life][target=focus-target,nomod,nochanneling: Drain Life] Drain Life; [target=player-target,mod:alt,harm][target=focus-target,mod:alt] Drain Mana; [target=player-target,mod:ctrl,harm][target=focus-target,mod:ctrl] Drain Soul(Rank 1)