bob-gray/solv

/* istanbul ignore if */
if (typeof define !== "function") {
    var define = require("amdefine")(module);
}

define(function (require) {
    "use strict";

    require("../array/from");

    var Emitter,
        meta = require("../meta"),
        createClass = require("../class"),
        event = require("../event");
    
    Emitter = createClass(
        meta({
            "name": "Emitter",
            "type": "class",
            "description": "Object oriented event API. Good for a base class or mixin."
        })
    );

    Emitter.method(
        meta({
            "name": "on",
            "description": "Adds a listener",
            "arguments": [{
                "name": "eventName",
                "type": "string"
            }, {
                "name": "handler",
                "type": "function"
            }],
            "returns": {
                "name": "listenerKey",
                "type": "object",
                "description": "Can be passed to .off to remove listener"
            }
        }),
        on
    );

    Emitter.method(
        meta({
            "name": "once",
            "description": "Adds a listener to be fired once",
            "arguments": [{
                "name": "eventName",
                "type": "string"
            }, {
                "name": "handler",
                "type": "function"
            }],
            "returns": {
                "name": "listenerKey",
                "type": "object",
                "description": "Can be passed to .off to remove listener"
            }
        }),
        once
    );

    Emitter.method(
        meta({
            "name": "off",
            "description": "Removes a listener",
            "arguments": [{
                "name": "listenerKey",
                "type": "object",
                "description": "Returned from .on or .once"
            }]
        }),
        offByListener
    );

    Emitter.method(
        meta({
            "name": "off",
            "description": "Removes all listeners of an event name",
            "arguments": [{
                "name": "eventName",
                "type": "string"
            }]
        }),
        offByEventName
    );

    Emitter.method(
        meta({
            "name": "off",
            "description": "Removes all listeners",
            "arguments": []
        }),
        allOff
    );

    Emitter.method(
        meta({
            "name": "trigger",
            "description": "Executes all handler functions listening for an event",
            "arguments": [{
                "name": "eventName",
                "type": "string"
            }, {
                "name": "nArgs",
                "type": "any",
                "required": false,
                "repeating": true,
                "description": "Additional arguments are passed to handler functions"
            }]
        }),
        trigger
    );

    Emitter.method(
        meta({
            "name": "trigger",
            "description": "Executes all handler functions listening for an event",
            "arguments": [{
                "name": "options",
                "type": "object",
                "properties": {
                    "name": "string",
                    "when": "string",
                    "params": "array"
                }
            }, {
                "name": "nArgs",
                "type": "any",
                "required": false,
                "repeating": true,
                "description": "Additional arguments are passed to handler functions"
            }]
        }),
        trigger
    );

    function on (eventName, handler) {
        return event.addListener(this, eventName, handler);
    }

    function once (eventName, handler) {
        return event.addListenerOnce(this, eventName, handler);
    }

    function offByListener (listenerKey) {
        event.removeListener(listenerKey);
    }

    function offByEventName (eventName) {
        event.removeListeners(this, eventName);
    }

    function allOff () {
        event.removeAllListeners(this);
    }

    function trigger () {
        var args = Array.from(arguments);
        
        args.unshift(this);
        event.trigger.apply(event, args);
    }

    return Emitter;
});