'use strict'

utils = require 'src/utils'
assert = require 'src/assert'

module.exports = (signal) -> class SignalsEmitter
    {callSignal} = signal

    NOP = ->

    handlerFunc = signal.createSignalFunction()

    @emitSignal = (obj, name, arg1, arg2) ->
        assert.isString name
        assert.notLengthOf name, 0

        if obj and (listeners = obj._signals[name])
            return callSignal obj, listeners, arg1, arg2

    @createSignalOnObject = (obj, name, onInitialized) ->
        assert.isObject obj
        assert.isString name
        assert.notLengthOf name, 0
        assert.isFunction onInitialized if onInitialized?

        getter = ->
            assert.instanceOf @, SignalsEmitter

            # http://jsperf.com/dynamic-structures
            signals = @_signals
            unless listeners = signals[name]
                listeners = signals[name] = [null, null, null, null]
                onInitialized? @, name
            handlerFunc.obj = @
            handlerFunc.listeners = listeners

            handlerFunc

        utils.defineProperty obj, name, null, getter, null

        getter

    @createSignal = (ctor, name, onInitialized) ->
        assert.isFunction ctor
        SignalsEmitter.createSignalOnObject ctor::, name, onInitialized

    constructor: ->
        @_signals = {}