Stop Casting A Channeling Spell When Stunned/Canceled

[lnfernal]

The title says it all. The only thing I know how to do this is the Condition. If you don't understand let me explain what I need help with.
If I use a channel spell made in GUI and I want that the hero who casted this spell will cancel the channel if his stunned or if he cancel the spell by walking away (or something). Of course I know that this can be different to different spells, but if you know a tutorial or you could at least explain the basics, please tell me.

But for example if I got a simple spell like this, how do I make a trigger that cancels it? (It's just an example!!!!!!!!)

Aoe_Spell
Events
Unit - A unit Starts the effect of an ability
Conditions
(Ability being cast) Equal to AoE_Spell
Actions
Turn on AoE_Spell_Effect
Set AoE_SpellCaster = Castin Unit
Wait 6 seconds
Turn off AoE_Spell_Effect


AoE_Spell_Effect
Event
Time - Every 1.00 seconds of game time
Special Effect - Create a special effect at (Random point in (Region centered at (Position of (AoE_SpellCaster)) with size (800.00, 800.00))) using Abilities\Spells\Human\ThunderClap\ThunderClap.mdl
Unit - Cause (AoE_SpellCaster) to damage circular area after 0.00 seconds of radius 800.00 at (Position of (AoE_SpellCaster)), dealing 100.00 damage of attack type Spells and damage type Normal

 

[Need_O2]

next time [trigger][/trigger] please

Unit Stops Casting Ability
Turn off AoE damage trigger