Tagged based damage receiver.

i have a basic damage receiver script that can take damage from any game Object scripted with a damage giver. what i want to do is have a game object with certain tag names to deliver damage.

Example: enemy tag fires a missile that damages a player but doesn't damage tag named enemy.

My Code:

Code (JavaScript):

1. var hitPoints = 100.0;
2. var detonationDelay = 0.0;
3. var explosion : Transform;
4. var deadReplacement : Rigidbody;
5.  
6. function ApplyDamage (damage : float) {
7.     // We already have less than 0 hitpoints, maybe we got killed already?
8.     if (hitPoints <= 0.0)
9.         return;
10.        
11.     hitPoints -= damage;
12.     if (hitPoints <= 0.0) {
13.         // Start emitting particles
14.         var emitter : ParticleEmitter = GetComponentInChildren(ParticleEmitter);
15.         if (emitter)
16.             emitter.emit = true;
17.  
18.         Invoke("DelayedDetonate", detonationDelay);
19.     }
20. }
21.  
22. function DelayedDetonate () {
23.     BroadcastMessage ("Detonate");
24. }
25.  
26. function Detonate () {
27.     // Destroy ourselves
28.     Destroy(gameObject);
29.  
30.     // Create the explosion
31.     if (explosion)
32.         Instantiate (explosion, transform.position, transform.rotation);
33.  
34.     // If we have a dead barrel then replace ourselves with it!
35.     if (deadReplacement) {
36.         var dead : Rigidbody = Instantiate(deadReplacement, transform.position, transform.rotation);
37.  
38.         // For better effect we assign the same velocity to the exploded barrel
39.         dead.rigidbody.velocity = rigidbody.velocity;
40.         dead.angularVelocity = rigidbody.angularVelocity;
41.     }
42.    
43.     // If there is a particle emitter stop emitting and detach so it doesnt get destroyed
44.     // right away
45.     var emitter : ParticleEmitter = GetComponentInChildren(ParticleEmitter);
46.     if (emitter) {
47.         emitter.emit = false;
48.         emitter.transform.parent = null;
49.     }
50. }
51.  
52. // We require the barrel to be a rigidbody, so that it can do nice physics
53. @script RequireComponent (Rigidbody)

how can i do this?