/**
 * V8Debugger
 * 
 * Copyright (c) 2010 Ajax.org B.V.
 * 
 * The MIT License (MIT)
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */
define(function(require, exports, module) {
"use strict";

exports.byteLength = function(str) {
    // returns the byte length of an utf8 string
    var s = str.length;
    for (var i = str.length - 1; i >= 0; i--) {
        var code = str.charCodeAt(i);
        if (code > 0x7f && code <= 0x7ff) s++;
        else if (code > 0x7ff && code <= 0xffff) s += 2;
        if (code >= 0xDC00 && code <= 0xDFFF) i--; // trail surrogate
    }
    return s;
};

exports.readBytes = function(str, start, bytes) {
    // returns the byte length of an utf8 string
    var consumed = 0;
    for (var i = start; i < str.length; i++) {
        var code = str.charCodeAt(i);
        if (code < 0x7f) consumed++;
        else if (code > 0x7f && code <= 0x7ff) consumed += 2;
        else if (code > 0x7ff && code <= 0xffff) consumed += 3;
        if (code >= 0xD800 && code <= 0xDBFF) i++; // leading surrogate
        if (consumed >= bytes) { i++; break; }
    }
    return { bytes: consumed, length: i - start };
};

exports.inherits = (function() {
    var tempCtor = function() {};
    return function(ctor, superCtor) {
        tempCtor.prototype = superCtor.prototype;
        ctor.super_ = superCtor.prototype;
        ctor.prototype = new tempCtor();
        ctor.prototype.constructor = ctor;
    };
}());

exports.mixin = function(obj, mixin) {
    for (var key in mixin)
        obj[key] = mixin[key];
};

exports.implement = function(proto, mixin) {
    exports.mixin(proto, mixin);
};

var EventEmitter = {};

EventEmitter._emit =
EventEmitter.emit =
EventEmitter._dispatchEvent = function(eventName, e) {
    this._eventRegistry = this._eventRegistry || {};

    var listeners = this._eventRegistry[eventName];
    if (!listeners || !listeners.length)
        return;

    e = e || {};
    e.type = eventName;

    for (var i = listeners.length - 1; i >= 0; i--)
        listeners[i](e);
};

EventEmitter.on =
EventEmitter.addEventListener = function(eventName, callback) {
    this._eventRegistry = this._eventRegistry || {};

    var listeners = this._eventRegistry[eventName];
    if (!listeners)
        listeners = this._eventRegistry[eventName] = [];

    if (listeners.indexOf(callback) == -1)
        listeners.push(callback);
};

EventEmitter.removeListener =
EventEmitter.removeEventListener = function(eventName, callback) {
    this._eventRegistry = this._eventRegistry || {};

    var listeners = this._eventRegistry[eventName];
    if (!listeners)
      return;

    var index = listeners.indexOf(callback);
    if (index !== -1)
        listeners.splice(index, 1);
};

EventEmitter.removeAllListeners = function(eventName) {
    if (this._eventRegistry)
        this._eventRegistry[eventName] = [];
};

exports.EventEmitter = EventEmitter;

});