How to choose the appropriate decorator

Question

I creating a game that use a AI. This AI'API has to 3 methods written in an Angular Service

Here's a the simplified code:

app.service('AI', [function(){
   return {
     offer: angular.noop,
     accept: angular.noop,
     reject: angular.noop
   }
}])

The difficult part is that the methods implementation (and so, how AI react) can change according to several parameters (nationality, age etc...).

I thought about use angular Decorator but I will need to choose between several decorator. I can create files/implementations:

• less-than-10.decorator.js
• less-than-20.decorator.js
• etc...

but how can I say:

"I have a 18 years old player... load less-than-20.decorator.js and apply decorator"

OR

"I have a 18 years old player... use this decorator instead of this one"

To resume: I want to do a conditional decorator (loading).

After some search I found a way to do this: Instead of return $delegate I can return the original service but I think it's not a pretty way...

Have you got a better solution?

Answer 1

Have you considered using a factory instead of a service?

// teenagerAI and adultAI could be values, constants, factories...
app.factory('createAI', function (teenagerAI, adultAI) {
   return function (aiType) {
       switch (aiType) {
       case 'teenager':
           return teenagerAI;
       case 'adult':
           return adultAI;
       }
   };
});

Then you can inject createAI and use it:

createAI('adult');