/* global require, describe, it */

var assert = require("assert");
var EventBus = require("../../js/EventBus");

describe("EventBus", function () {

    describe(".prototype.subscribe(channel, listener)", function () {

        it("should subscribe a listener to listen for messages on a channel", function (done) {

            var bus = new EventBus();

            bus.subscribe("foo", function () {
                done();
            });

            bus.trigger("foo");
        });

        it("should work with any order of the arguments.", function (done) {

            var bus = new EventBus();

            bus.subscribe(function () {
                done();
            }, "foo");

            bus.trigger("foo");
        });

        it("shouldn't work with channel names other than strings or numbers.", function (done) {

            var bus = new EventBus();

            [null, undefined, ["bar"], {bar: "baz"}].forEach(function (value) {

                try {

                    bus.subscribe(value, function () {
                        done(new Error("Channel names may only be strings or numbers."));
                    });

                    bus.trigger(value);
                }
                catch (error) {}
            });

            done();
        });

    });


    describe(".prototype.unsubscribe(channel, listener)", function () {

        it("should unsubscribe a subscribed listener from a channel.", function (done) {

            var bus = new EventBus();
            var listenerCalled = false;

            function listener () {
                listenerCalled = true;
            }

            bus.subscribe("foo", listener);
            bus.unsubscribe("foo", listener);

            bus.trigger("foo", null, false);

            assert(!listenerCalled, "Listener should not be called after unsubscribing.");

            done();
        });

        it("should work with any order of the arguments.", function (done) {

            var bus = new EventBus();
            var listenerCalled = false;

            function listener () {
                listenerCalled = true;
            }

            bus.subscribe(listener, "foo");
            bus.unsubscribe(listener, "foo");

            bus.trigger("foo", null, false);

            assert(!listenerCalled, "Listener should not be called after unsubscribing.");

            done();
        });

    });


    describe(".prototype.trigger(channel, data, async)", function () {

        it("should cause all subscribed listeners on a channel to be executed.", function (done) {

            var bus = new EventBus();
            var numberOfListenersCalled = 0;
            var maxNumberOfListeners = 1000;
            var i;

            function makeListener () {
                return function () {
                    numberOfListenersCalled += 1;
                };
            }

            for (i = 0; i < 1000; i += 1) {
                bus.subscribe("foo", makeListener());
            }

            bus.trigger("foo", null, false);

            assert.equal(numberOfListenersCalled, maxNumberOfListeners);

            done();
        });

        it("should supply the listeners with the data used in the call.", function (done) {

            var bus = new EventBus();
            var data = {foo: "bar"};
            var numberOfListenersCalled = 0;
            var maxNumberOfListeners = 1000;
            var i;

            function makeListener () {
                return function (suppliedData) {
                    assert.equal(suppliedData, data);
                };
            }

            for (i = 0; i < 1000; i += 1) {
                bus.subscribe("foo", makeListener());
            }

            bus.trigger("foo", data, false);

            done();
        });

    });

});