Get Class Instance from Within Decorator

I'm attempting to get my mind completely wrapped around decorators, and I had a couple neat ideas where I could use them in a reflux implementation I'm working on. I want to tag a store's class method with an action, and any time that action is generated, it knows to call any methods tagged with it.

First, I want to tag the Store method:

@Action
public setData(data: FakeData) {
    console.log(this);
    this.state.data = data;
}

then, in the action class, I want to register that method in an array:

class Action {
    private static methods: Method<FakeData>[] = [];

    public static register(method: Method<FakeData>) {
        this.methods.push(method);
    }

    constructor(payload: FakeData);
    constructor(store: Store, method: string);
    constructor(payload: any, method?: string, descriptor?: PropertyDescriptor) {
        if (method) {
            //TODO need actual instance of class here....
            Action.register(payload[method].bind(payload));
            return;
        }

        this.trigger(payload);
    }

    public get payload() {
        return Math.random();
    }

    private trigger(payload: FakeData) {
        Action.methods.forEach(m => m(payload));
    }
}

However, inside the constructor I do not have access to the actual instance of the store. I am able to get the constructor, but I'm not sure I am able to use that to achieve my goal. Perhaps instead of a constructor, I should make all stores strictly static?

I'm sure I'm not thinking about these decorators the right way, so any insight is appreciated!

Link to full code on Typescript Playground