/*
Copyright (c) 2006, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://developer.yahoo.com/yui/license.txt
version: 0.11.3
*/

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/
/**
 * Singleton providing core logging functionality. Saves logs written through the
 * global YAHOO.log function or written by LogWriter. Provides access to logs
 * for reading by LogReader. Log messages can be automatically output to browser
 * console such as the Firebug extension to Firefox or Safari's JavaScript
 * console, if present.
 *
 * requires YAHOO.util.Event Event utility
 */
YAHOO.widget.Logger = {
    // Initialize members
    loggerEnabled: true,
    _browserConsoleEnabled: false,
    categories: ["info","warn","error","time","window"],
    sources: ["global"],
    _stack: [], // holds all log msgs
    maxStackEntries: 5,
    _startTime: new Date().getTime(), // static start timestamp
    _lastTime: null // timestamp of last logged message
};

/***************************************************************************
 * Events
 ***************************************************************************/
/**
 * Fired when a new category has been created. Subscribers receive the following
 * array:<br>
 *     - args[0] The category name
 */
YAHOO.widget.Logger.categoryCreateEvent = new YAHOO.util.CustomEvent("categoryCreate", this, true);

/**
 * Fired when a new source has been named. Subscribers receive the following
 * array:<br>
 *     - args[0] The source name
 */
YAHOO.widget.Logger.sourceCreateEvent = new YAHOO.util.CustomEvent("sourceCreate", this, true);

/**
 * Fired when a new log message has been created. Subscribers receive the
 * following array:<br>
 *     - args[0] The log message
 */
YAHOO.widget.Logger.newLogEvent = new YAHOO.util.CustomEvent("newLog", this, true);

/**
 * Fired when the Logger has been reset has been created.
 */
YAHOO.widget.Logger.logResetEvent = new YAHOO.util.CustomEvent("logReset", this, true);

/***************************************************************************
 * Public methods
 ***************************************************************************/
/**
 * Saves a log message to the stack and fires newLogEvent. If the log message is
 * assigned to an unknown category, creates a new category. If the log message is
 * from an unknown source, creates a new source.  If browser console is enabled,
 * outputs the log message to browser console.
 *
 * @param {string} sMsg The log message
 * @param {string} sCategory Category of log message, or null
 * @param {string} sSource Source of LogWriter, or null if global
 */
YAHOO.widget.Logger.log = function(sMsg, sCategory, sSource) {
    if(this.loggerEnabled) {
        if(!sCategory) {
            sCategory = "info"; // default category
        }
        else {
            sCategory = sCategory.toLocaleLowerCase();
            if(this._isNewCategory(sCategory)) {
                this._createNewCategory(sCategory);
            }
        }
        var sClass = "global"; // default source
        var sDetail = null;
        if(sSource) {
            var spaceIndex = sSource.indexOf(" ");
            if(spaceIndex > 0) {
                sClass = sSource.substring(0,spaceIndex);// substring until first space
                sDetail = sSource.substring(spaceIndex,sSource.length);// the rest of the source
            }
            else {
                sClass = sSource;
            }
            if(this._isNewSource(sClass)) {
                this._createNewSource(sClass);
            }
        }

        var timestamp = new Date();
        var logEntry = {
            time: timestamp,
            category: sCategory,
            source: sClass,
            sourceDetail: sDetail,
            msg: sMsg
        };

        var stack = this._stack;
        var maxStackEntries = this.maxStackEntries;
        if(maxStackEntries && !isNaN(maxStackEntries) && (stack.length >= maxStackEntries)) {
            stack.shift();
        }
        stack.push(logEntry);
        this.newLogEvent.fire(logEntry);

        if(this._browserConsoleEnabled) {
            this._printToBrowserConsole(logEntry);
        }
        return true;
    }
    else {
        return false;
    }
};

/**
 * Resets internal stack and startTime, enables Logger, and fires logResetEvent.
 *
 */
YAHOO.widget.Logger.reset = function() {
    this._stack = [];
    this._startTime = new Date().getTime();
    this.loggerEnabled = true;
    this.log("Logger reset");
    this.logResetEvent.fire();
};

/**
 * Public accessor to internal stack of log messages.
 *
 * @return {array} Array of log messages.
 */
YAHOO.widget.Logger.getStack = function() {
    return this._stack;
};

/**
 * Public accessor to internal start time.
 *
 * @return {date} Internal date of when Logger singleton was initialized.
 */
YAHOO.widget.Logger.getStartTime = function() {
    return this._startTime;
};

/**
 * Disables output to the browser's global console.log() function, which is used
 * by the Firebug extension to Firefox as well as Safari.
 */
YAHOO.widget.Logger.disableBrowserConsole = function() {
    YAHOO.log("Logger output to the function console.log() has been disabled.");
    this._browserConsoleEnabled = false;
};

/**
 * Enables output to the browser's global console.log() function, which is used
 * by the Firebug extension to Firefox as well as Safari.
 */
YAHOO.widget.Logger.enableBrowserConsole = function() {
    this._browserConsoleEnabled = true;
    YAHOO.log("Logger output to the function console.log() has been enabled.");
};

/***************************************************************************
 * Private methods
 ***************************************************************************/
/**
 * Creates a new category of log messages and fires categoryCreateEvent.
 *
 * @param {string} category Category name
 * @private
 */
YAHOO.widget.Logger._createNewCategory = function(category) {
    this.categories.push(category);
    this.categoryCreateEvent.fire(category);
};

/**
 * Checks to see if a category has already been created.
 *
 * @param {string} category Category name
 * @return {boolean} Returns true if category is unknown, else returns false
 * @private
 */
YAHOO.widget.Logger._isNewCategory = function(category) {
    for(var i=0; i < this.categories.length; i++) {
        if(category == this.categories[i]) {
            return false;
        }
    }
    return true;
};

/**
 * Creates a new source of log messages and fires sourceCreateEvent.
 *
 * @param {string} source Source name
 * @private
 */
YAHOO.widget.Logger._createNewSource = function(source) {
    this.sources.push(source);
    this.sourceCreateEvent.fire(source);
};

/**
 * Checks to see if a source has already been created.
 *
 * @param {string} source Source name
 * @return {boolean} Returns true if source is unknown, else returns false
 * @private
 */
YAHOO.widget.Logger._isNewSource = function(source) {
    if(source) {
        for(var i=0; i < this.sources.length; i++) {
            if(source == this.sources[i]) {
                return false;
            }
        }
        return true;
    }
};

/**
 * Outputs a log message to global console.log() function.
 *
 * @param {object} entry Log entry object
 * @private
 */
YAHOO.widget.Logger._printToBrowserConsole = function(entry) {
    if(window.console && console.log) {
        var category = entry.category;
        var label = entry.category.substring(0,4).toUpperCase();

        var time = entry.time;
        if (time.toLocaleTimeString) {
            var localTime  = time.toLocaleTimeString();
        }
        else {
            localTime = time.toString();
        }

        var msecs = time.getTime();
        var elapsedTime = (YAHOO.widget.Logger._lastTime) ?
            (msecs - YAHOO.widget.Logger._lastTime) : 0;
        YAHOO.widget.Logger._lastTime = msecs;

        var output =
            localTime + " (" +
            elapsedTime + "ms): " +
            entry.source + ": " +
            entry.msg;

        console.log(output);
    }
};

/***************************************************************************
 * Private event handlers
 ***************************************************************************/
/**
 * Handles logging of messages due to window error events.
 *
 * @param {string} msg The error message
 * @param {string} url URL of the error
 * @param {string} line Line number of the error
 * @private
 */
YAHOO.widget.Logger._onWindowError = function(msg,url,line) {
    // Logger is not in scope of this event handler
    try {
        YAHOO.widget.Logger.log(msg+' ('+url+', line '+line+')', "window");
        if(YAHOO.widget.Logger._origOnWindowError) {
            YAHOO.widget.Logger._origOnWindowError();
        }
    }
    catch(e) {
        return false;
    }
};

/**
 * Handle native JavaScript errors
 */
//NB: Not all browsers support the window.onerror event
if(window.onerror) {
    // Save any previously defined handler to call
    YAHOO.widget.Logger._origOnWindowError = window.onerror;
}
window.onerror = YAHOO.widget.Logger._onWindowError;

/**
 * First log
 */
YAHOO.widget.Logger.log("Logger initialized");

/****************************************************************************/
/****************************************************************************/
/****************************************************************************/
/**
 * Class providing ability to log messages through YAHOO.widget.Logger from a
 * named source.
 *
 * @constructor
 * @param {string} sSource Source of LogWriter instance
 */
YAHOO.widget.LogWriter = function(sSource) {
    if(!sSource) {
        YAHOO.log("Could not instantiate LogWriter due to invalid source.", "error", "LogWriter");
        return;
    }
    this._source = sSource;
 };

/***************************************************************************
 * Public methods
 ***************************************************************************/
 /**
 * Public accessor to the unique name of the LogWriter instance.
 *
 * @return {string} Unique name of the LogWriter instance
 */
YAHOO.widget.LogWriter.prototype.toString = function() {
    return "LogWriter " + this._sSource;
};

/**
 * Logs a message attached to the source of the LogWriter.
 *
 * @param {string} sMsg The log message
 * @param {string} sCategory Category name
 */
YAHOO.widget.LogWriter.prototype.log = function(sMsg, sCategory) {
    YAHOO.widget.Logger.log(sMsg, sCategory, this._source);
};

/**
 * Public accessor to get the source name.
 *
 * @return {string} The LogWriter source
 */
YAHOO.widget.LogWriter.prototype.getSource = function() {
    return this._sSource;
};

/**
 * Public accessor to set the source name.
 *
 * @param {string} sSource Source of LogWriter instance
 */
YAHOO.widget.LogWriter.prototype.setSource = function(sSource) {
    if(!sSource) {
        YAHOO.log("Could not set source due to invalid source.", "error", this.toString());
        return;
    }
    else {
        this._sSource = sSource;
    }
};
/***************************************************************************
 * Private members
 ***************************************************************************/
/**
 * Source of the log writer instance.
 *
 * @type string
 * @private
 */
YAHOO.widget.LogWriter.prototype._source = null;



/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * Class providing UI to read messages logged to YAHOO.widget.Logger.
 *
 * requires YAHOO.util.Dom DOM utility
 * requires YAHOO.util.Event Event utility
 * optional YAHOO.util.DragDrop Drag and drop utility
 *
 * @constructor
 * @param {el or ID} containerEl DOM element object or ID of container to wrap reader UI
 * @param {object} oConfig Optional object literal of configuration params
 */
YAHOO.widget.LogReader = function(containerEl, oConfig) {
    var oSelf = this;
    this._sName = YAHOO.widget.LogReader._index;
    YAHOO.widget.LogReader._index++;

    // Parse config vars here
    if (typeof oConfig == "object") {
        for(var param in oConfig) {
            this[param] = oConfig[param];
        }
    }

    // Attach container...
    if(containerEl) {
        if(typeof containerEl == "string") {
            this._containerEl = document.getElementById(containerEl);
        }
        else if(containerEl.tagName) {
            this._containerEl = containerEl;
        }
        this._containerEl.className = "yui-log";
    }
    // ...or create container from scratch
    if(!this._containerEl) {
        if(YAHOO.widget.LogReader._defaultContainerEl) {
            this._containerEl =  YAHOO.widget.LogReader._defaultContainerEl;
        }
        else {
            this._containerEl = document.body.appendChild(document.createElement("div"));
            this._containerEl.id = "yui-log";
            this._containerEl.className = "yui-log";

            YAHOO.widget.LogReader._defaultContainerEl = this._containerEl;
        }

        // If implementer has provided container values, trust and set those
        var containerStyle = this._containerEl.style;
        if(this.width) {
            containerStyle.width = this.width;
        }
        if(this.left) {
            containerStyle.left = this.left;
        }
        if(this.right) {
            containerStyle.right = this.right;
        }
        if(this.bottom) {
            containerStyle.bottom = this.bottom;
        }
        if(this.top) {
            containerStyle.top = this.top;
        }
        if(this.fontSize) {
            containerStyle.fontSize = this.fontSize;
        }
    }

    if(this._containerEl) {
        // Create header
        if(!this._hdEl) {
            this._hdEl = this._containerEl.appendChild(document.createElement("div"));
            this._hdEl.id = "yui-log-hd" + this._sName;
            this._hdEl.className = "yui-log-hd";

            this._collapseEl = this._hdEl.appendChild(document.createElement("div"));
            this._collapseEl.className = "yui-log-btns";

            this._collapseBtn = document.createElement("input");
            this._collapseBtn.type = "button";
            this._collapseBtn.style.fontSize = YAHOO.util.Dom.getStyle(this._containerEl,"fontSize");
            this._collapseBtn.className = "yui-log-button";
            this._collapseBtn.value = "Collapse";
            this._collapseBtn = this._collapseEl.appendChild(this._collapseBtn);
            YAHOO.util.Event.addListener(oSelf._collapseBtn,'click',oSelf._onClickCollapseBtn,oSelf);

            this._title = this._hdEl.appendChild(document.createElement("h4"));
            this._title.innerHTML = "Logger Console";

            // If Drag and Drop utility is available...
            // ...and this container was created from scratch...
            // ...then make the header draggable
            if(YAHOO.util.DD &&
            (YAHOO.widget.LogReader._defaultContainerEl == this._containerEl)) {
                var ylog_dd = new YAHOO.util.DD(this._containerEl.id);
                ylog_dd.setHandleElId(this._hdEl.id);
                this._hdEl.style.cursor = "move";
            }
        }
        // Ceate console
        if(!this._consoleEl) {
            this._consoleEl = this._containerEl.appendChild(document.createElement("div"));
            this._consoleEl.className = "yui-log-bd";

            // If implementer has provided console, trust and set those
            if(this.height) {
                this._consoleEl.style.height = this.height;
            }
        }
        // Don't create footer if disabled
        if(!this._ftEl && this.footerEnabled) {
            this._ftEl = this._containerEl.appendChild(document.createElement("div"));
            this._ftEl.className = "yui-log-ft";

            this._btnsEl = this._ftEl.appendChild(document.createElement("div"));
            this._btnsEl.className = "yui-log-btns";

            this._pauseBtn = document.createElement("input");
            this._pauseBtn.type = "button";
            this._pauseBtn.style.fontSize = YAHOO.util.Dom.getStyle(this._containerEl,"fontSize");
            this._pauseBtn.className = "yui-log-button";
            this._pauseBtn.value = "Pause";
            this._pauseBtn = this._btnsEl.appendChild(this._pauseBtn);
            YAHOO.util.Event.addListener(oSelf._pauseBtn,'click',oSelf._onClickPauseBtn,oSelf);

            this._clearBtn = document.createElement("input");
            this._clearBtn.type = "button";
            this._clearBtn.style.fontSize = YAHOO.util.Dom.getStyle(this._containerEl,"fontSize");
            this._clearBtn.className = "yui-log-button";
            this._clearBtn.value = "Clear";
            this._clearBtn = this._btnsEl.appendChild(this._clearBtn);
            YAHOO.util.Event.addListener(oSelf._clearBtn,'click',oSelf._onClickClearBtn,oSelf);

            this._categoryFiltersEl = this._ftEl.appendChild(document.createElement("div"));
            this._categoryFiltersEl.className = "yui-log-categoryfilters";
            this._sourceFiltersEl = this._ftEl.appendChild(document.createElement("div"));
            this._sourceFiltersEl.className = "yui-log-sourcefilters";
        }
    }

    // Initialize internal vars
    if(!this._buffer) {
        this._buffer = []; // output buffer
    }
    this._lastTime = YAHOO.widget.Logger.getStartTime(); // timestamp of last log message to console
    
    // Subscribe to Logger custom events
    YAHOO.widget.Logger.newLogEvent.subscribe(this._onNewLog, this);
    YAHOO.widget.Logger.logResetEvent.subscribe(this._onReset, this);

    // Initialize category filters
    this._categoryFilters = [];
    var catsLen = YAHOO.widget.Logger.categories.length;
    if(this._categoryFiltersEl) {
        for(var i=0; i < catsLen; i++) {
            this._createCategoryCheckbox(YAHOO.widget.Logger.categories[i]);
        }
    }
    // Initialize source filters
    this._sourceFilters = [];
    var sourcesLen = YAHOO.widget.Logger.sources.length;
    if(this._sourceFiltersEl) {
        for(var j=0; j < sourcesLen; j++) {
            this._createSourceCheckbox(YAHOO.widget.Logger.sources[j]);
        }
    }
    YAHOO.widget.Logger.categoryCreateEvent.subscribe(this._onCategoryCreate, this);
    YAHOO.widget.Logger.sourceCreateEvent.subscribe(this._onSourceCreate, this);

    this._filterLogs();
    YAHOO.log("LogReader initialized", null, this.toString());
};

/***************************************************************************
 * Public members
 ***************************************************************************/
/**
 * Whether or not the log reader is enabled to output log messages. Default:
 * true.
 *
 * @type boolean
 */
YAHOO.widget.LogReader.prototype.logReaderEnabled = true;

/**
 * Public member to access CSS width of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.width = null;

/**
 * Public member to access CSS height of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.height = null;

/**
 * Public member to access CSS top position of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.top = null;

/**
 * Public member to access CSS left position of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.left = null;

/**
 * Public member to access CSS right position of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.right = null;

/**
 * Public member to access CSS bottom position of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.bottom = null;

/**
 * Public member to access CSS font size of the log reader container.
 *
 * @type string
 */
YAHOO.widget.LogReader.prototype.fontSize = null;

/**
 * Whether or not the footer UI is enabled for the log reader. Default: true.
 *
 * @type boolean
 */
YAHOO.widget.LogReader.prototype.footerEnabled = true;

/**
 * Whether or not output is verbose (more readable). Setting to true will make
 * output more compact (less readable). Default: true.
 *
 * @type boolean
 */
YAHOO.widget.LogReader.prototype.verboseOutput = true;

/**
 * Whether or not newest message is printed on top. Default: true.
 *
 * @type boolean
 */
YAHOO.widget.LogReader.prototype.newestOnTop = true;

/**
 * Maximum number of messages a LogReader console will display. Default: 500;
 *
 * @type number
 */
YAHOO.widget.LogReader.prototype.thresholdMax = 500;

/**
 * When a LogReader console reaches its thresholdMax, it will clear out messages
 * and print out the latest thresholdMin number of messages. Default: 100;
 *
 * @type number
 */
YAHOO.widget.LogReader.prototype.thresholdMin = 100;

/***************************************************************************
 * Public methods
 ***************************************************************************/
 /**
 * Public accessor to the unique name of the LogReader instance.
 *
 * @return {string} Unique name of the LogReader instance
 */
YAHOO.widget.LogReader.prototype.toString = function() {
    return "LogReader instance" + this._sName;
};
/**
 * Pauses output of log messages. While paused, log messages are not lost, but
 * get saved to a buffer and then output upon resume of log reader.
 */
YAHOO.widget.LogReader.prototype.pause = function() {
    this._timeout = null;
    this.logReaderEnabled = false;
};

/**
 * Resumes output of log messages, including outputting any log messages that
 * have been saved to buffer while paused.
 */
YAHOO.widget.LogReader.prototype.resume = function() {
    this.logReaderEnabled = true;
    this._printBuffer();
};

/**
 * Hides UI of log reader. Logging functionality is not disrupted.
 */
YAHOO.widget.LogReader.prototype.hide = function() {
    this._containerEl.style.display = "none";
};

/**
 * Shows UI of log reader. Logging functionality is not disrupted.
 */
YAHOO.widget.LogReader.prototype.show = function() {
    this._containerEl.style.display = "block";
};

/**
 * Updates title to given string.
 *
 * @param {string} sTitle String to display in log reader's title bar.
 */
YAHOO.widget.LogReader.prototype.setTitle = function(sTitle) {
    this._title.innerHTML = this._HTML2Text(sTitle);
};
 /***************************************************************************
 * Private members
 ***************************************************************************/
/**
 * Internal class member to index multiple log reader instances.
 *
 * @type number
 * @private
 */
YAHOO.widget.LogReader._index = 0;

/**
 * Name of LogReader instance.
 *
 * @type string
 * @private
 */
YAHOO.widget.LogReader.prototype._sName = null;

/**
 * A class member shared by all log readers if a container needs to be
 * created during instantiation. Will be null if a container element never needs to
 * be created on the fly, such as when the implementer passes in their own element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader._defaultContainerEl = null;

/**
 * Buffer of log messages for batch output.
 *
 * @type array
 * @private
 */
YAHOO.widget.LogReader.prototype._buffer = null;

/**
 * Number of log messages output to console.
 *
 * @type number
 * @private
 */
YAHOO.widget.LogReader.prototype._consoleMsgCount = 0;

/**
 * Date of last output log message.
 *
 * @type date
 * @private
 */
YAHOO.widget.LogReader.prototype._lastTime = null;

/**
 * Batched output timeout ID.
 *
 * @type number
 * @private
 */
YAHOO.widget.LogReader.prototype._timeout = null;

/**
 * Array of filters for log message categories.
 *
 * @type array
 * @private
 */
YAHOO.widget.LogReader.prototype._categoryFilters = null;

/**
 * Array of filters for log message sources.
 *
 * @type array
 * @private
 */
YAHOO.widget.LogReader.prototype._sourceFilters = null;

/**
 * Log reader container element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._containerEl = null;

/**
 * Log reader header element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._hdEl = null;

/**
 * Log reader collapse element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._collapseEl = null;

/**
 * Log reader collapse button element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._collapseBtn = null;

/**
 * Log reader title header element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._title = null;

/**
 * Log reader console element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._consoleEl = null;

/**
 * Log reader footer element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._ftEl = null;

/**
 * Log reader buttons container element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._btnsEl = null;

/**
 * Container element for log reader category filter checkboxes.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._categoryFiltersEl = null;

/**
 * Container element for log reader source filter checkboxes.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._sourceFiltersEl = null;

/**
 * Log reader pause button element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._pauseBtn = null;

/**
 * Clear button element.
 *
 * @type HTMLElement
 * @private
 */
YAHOO.widget.LogReader.prototype._clearBtn = null;
/***************************************************************************
 * Private methods
 ***************************************************************************/
/**
 * Creates the UI for a category filter in the log reader footer element.
 *
 * @param {string} category Category name
 * @private
 */
YAHOO.widget.LogReader.prototype._createCategoryCheckbox = function(category) {
    var oSelf = this;

    if(this._ftEl) {
        var parentEl = this._categoryFiltersEl;
        var filters = this._categoryFilters;

        var filterEl = parentEl.appendChild(document.createElement("span"));
        filterEl.className = "yui-log-filtergrp";
            // Append el at the end so IE 5.5 can set "type" attribute
            // and THEN set checked property
            var categoryChk = document.createElement("input");
            categoryChk.id = "yui-log-filter-" + category + this._sName;
            categoryChk.className = "yui-log-filter-" + category;
            categoryChk.type = "checkbox";
            categoryChk.category = category;
            categoryChk = filterEl.appendChild(categoryChk);
            categoryChk.checked = true;

            // Add this checked filter to the internal array of filters
            filters.push(category);
            // Subscribe to the click event
            YAHOO.util.Event.addListener(categoryChk,'click',oSelf._onCheckCategory,oSelf);

            // Create and class the text label
            var categoryChkLbl = filterEl.appendChild(document.createElement("label"));
            categoryChkLbl.htmlFor = categoryChk.id;
            categoryChkLbl.className = category;
            categoryChkLbl.innerHTML = category;
    }
};

YAHOO.widget.LogReader.prototype._createSourceCheckbox = function(source) {
    var oSelf = this;

    if(this._ftEl) {
        var parentEl = this._sourceFiltersEl;
        var filters = this._sourceFilters;

        var filterEl = parentEl.appendChild(document.createElement("span"));
        filterEl.className = "yui-log-filtergrp";

        // Append el at the end so IE 5.5 can set "type" attribute
        // and THEN set checked property
        var sourceChk = document.createElement("input");
        sourceChk.id = "yui-log-filter" + source + this._sName;
        sourceChk.className = "yui-log-filter" + source;
        sourceChk.type = "checkbox";
        sourceChk.source = source;
        sourceChk = filterEl.appendChild(sourceChk);
        sourceChk.checked = true;

        // Add this checked filter to the internal array of filters
        filters.push(source);
        // Subscribe to the click event
        YAHOO.util.Event.addListener(sourceChk,'click',oSelf._onCheckSource,oSelf);

        // Create and class the text label
        var sourceChkLbl = filterEl.appendChild(document.createElement("label"));
        sourceChkLbl.htmlFor = sourceChk.id;
        sourceChkLbl.className = source;
        sourceChkLbl.innerHTML = source;
    }
};

/**
 * Reprints all log messages in the stack through filters.
 *
 * @private
 */
YAHOO.widget.LogReader.prototype._filterLogs = function() {
    // Reprint stack with new filters
    if (this._consoleEl !== null) {
        this._clearConsole();
        this._printToConsole(YAHOO.widget.Logger.getStack());
    }
};

/**
 * Clears all outputted log messages from the console and resets the time of the
 * last output log message.
 *
 * @private
 */
YAHOO.widget.LogReader.prototype._clearConsole = function() {
    // Clear the buffer of any pending messages
    this._timeout = null;
    this._buffer = [];
    this._consoleMsgCount = 0;

    // Reset the rolling timer
    this._lastTime = YAHOO.widget.Logger.getStartTime();

    var consoleEl = this._consoleEl;
    while(consoleEl.hasChildNodes()) {
        consoleEl.removeChild(consoleEl.firstChild);
    }
};

/**
 * Sends buffer of log messages to output and clears buffer.
 *
 * @private
 */
YAHOO.widget.LogReader.prototype._printBuffer = function() {
    this._timeout = null;

    if(this._consoleEl !== null) {
        var thresholdMax = this.thresholdMax;
        thresholdMax = (thresholdMax && !isNaN(thresholdMax)) ? thresholdMax : 500;
        if(this._consoleMsgCount < thresholdMax) {
            var entries = [];
            for (var i=0; i<this._buffer.length; i++) {
                entries[i] = this._buffer[i];
            }
            this._buffer = [];
            this._printToConsole(entries);
        }
        else {
            this._filterLogs();
        }
        
        if(!this.newestOnTop) {
            this._consoleEl.scrollTop = this._consoleEl.scrollHeight;
        }
    }
};

/**
 * Cycles through an array of log messages, and outputs each one to the console
 * if its category has not been filtered out.
 *
 * @param {array} aEntries
 * @private
 */
YAHOO.widget.LogReader.prototype._printToConsole = function(aEntries) {
    // Manage the number of messages displayed in the console
    var entriesLen = aEntries.length;
    var thresholdMin = this.thresholdMin;
    if(isNaN(thresholdMin) || (thresholdMin > this.thresholdMax)) {
        thresholdMin = 0;
    }
    var entriesStartIndex = (entriesLen > thresholdMin) ? (entriesLen - thresholdMin) : 0;
    
    // Iterate through all log entries to print the ones that filter through
    var sourceFiltersLen = this._sourceFilters.length;
    var categoryFiltersLen = this._categoryFilters.length;
    for(var i=entriesStartIndex; i<entriesLen; i++) {
        var entry = aEntries[i];
        var category = entry.category;
        var source = entry.source;
        var sourceDetail = entry.sourceDetail;
        var okToPrint = false;
        var okToFilterCats = false;

        for(var j=0; j<sourceFiltersLen; j++) {
            if(source == this._sourceFilters[j]) {
                okToFilterCats = true;
                break;
            }
        }
        if(okToFilterCats) {
            for(var k=0; k<categoryFiltersLen; k++) {
                if(category == this._categoryFilters[k]) {
                    okToPrint = true;
                    break;
                }
            }
        }
        if(okToPrint) {
            // To format for console, calculate the elapsed time
            // to be from the last item that passed through the filter,
            // not the absolute previous item in the stack
            var label = entry.category.substring(0,4).toUpperCase();

            var time = entry.time;
            if (time.toLocaleTimeString) {
                var localTime  = time.toLocaleTimeString();
            }
            else {
                localTime = time.toString();
            }

            var msecs = time.getTime();
            var startTime = YAHOO.widget.Logger.getStartTime();
            var totalTime = msecs - startTime;
            var elapsedTime = msecs - this._lastTime;
            this._lastTime = msecs;

            var verboseOutput = (this.verboseOutput);
            var container = (verboseOutput) ? "CODE" : "PRE";
            var sourceAndDetail = (sourceDetail) ?
                source + " " + sourceDetail : source;

            // Verbose uses code tag instead of pre tag (for wrapping)
            // and includes extra line breaks
            var output =  (verboseOutput) ?
                ["<p><span class='", category, "'>", label, "</span> ",
                totalTime, "ms (+", elapsedTime, ") ",
                localTime, ": ",
                "</p><p>",
                sourceAndDetail,
                ": </p><p>",
                this._HTML2Text(entry.msg),
                "</p>"] :
                
                ["<p><span class='", category, "'>", label, "</span> ",
                totalTime, "ms (+", elapsedTime, ") ",
                localTime, ": ",
                sourceAndDetail, ": ",
                this._HTML2Text(entry.msg),"</p>"];

            var oNewElement = (this.newestOnTop) ?
                this._consoleEl.insertBefore(document.createElement(container),this._consoleEl.firstChild):
                this._consoleEl.appendChild(document.createElement(container));

            oNewElement.innerHTML = output.join("");
            this._consoleMsgCount++;
        }
    }
};

/**
 * Converts input chars "<", ">", and "&" to HTML entities.
 *
 * @private
 */
YAHOO.widget.LogReader.prototype._HTML2Text = function(html) {
    if(html) {
        return html.replace(/&/g, "&#38;").replace(/</g, "&#60;").replace(/>/g, "&#62;");
    }
    else return "";
};

/***************************************************************************
 * Private event handlers
 ***************************************************************************/
/**
 * Handles Logger's categoryCreateEvent.
 *
 * @param {string} type The event
 * @param {array} args Data passed from event firer
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onCategoryCreate = function(type, args, oSelf) {
    var category = args[0];
    if(oSelf._ftEl) {
        oSelf._createCategoryCheckbox(category);
    }
};

/**
 * Handles Logger's sourceCreateEvent.
 *
 * @param {string} type The event
 * @param {array} args Data passed from event firer
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onSourceCreate = function(type, args, oSelf) {
    var source = args[0];
    if(oSelf._ftEl) {
        oSelf._createSourceCheckbox(source);
    }
};

/**
 * Handles check events on the category filter checkboxes.
 *
 * @param {event} v The click event
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onCheckCategory = function(v, oSelf) {
    var newFilter = this.category;
    var filtersArray = oSelf._categoryFilters;

    if(!this.checked) { // Remove category from filters
        for(var i=0; i<filtersArray.length; i++) {
            if(newFilter == filtersArray[i]) {
                filtersArray.splice(i, 1);
                break;
            }
        }
    }
    else { // Add category to filters
        filtersArray.push(newFilter);
    }
    oSelf._filterLogs();
};

/**
 * Handles check events on the category filter checkboxes.
 *
 * @param {event} v The click event
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onCheckSource = function(v, oSelf) {
    var newFilter = this.source;
    var filtersArray = oSelf._sourceFilters;

    if(!this.checked) { // Remove category from filters
        for(var i=0; i<filtersArray.length; i++) {
            if(newFilter == filtersArray[i]) {
                filtersArray.splice(i, 1);
                break;
            }
        }
    }
    else { // Add category to filters
        filtersArray.push(newFilter);
    }
    oSelf._filterLogs();
};

/**
 * Handles click events on the collapse button.
 *
 * @param {event} v The click event
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onClickCollapseBtn = function(v, oSelf) {
    var btn = oSelf._collapseBtn;
    if(btn.value == "Expand") {
        oSelf._consoleEl.style.display = "block";
        if(oSelf._ftEl) {
            oSelf._ftEl.style.display = "block";
        }
        btn.value = "Collapse";
    }
    else {
        oSelf._consoleEl.style.display = "none";
        if(oSelf._ftEl) {
            oSelf._ftEl.style.display = "none";
        }
        btn.value = "Expand";
    }
};

/**
 * Handles click events on the pause button.
 *
 * @param {event} v The click event
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onClickPauseBtn = function(v, oSelf) {
    var btn = oSelf._pauseBtn;
    if(btn.value == "Resume") {
        oSelf.resume();
        btn.value = "Pause";
    }
    else {
        oSelf.pause();
        btn.value = "Resume";
    }
};

/**
 * Handles click events on the clear button.
 *
 * @param {event} v The click event
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onClickClearBtn = function(v, oSelf) {
    oSelf._clearConsole();
};

/**
 * Handles Logger's newLogEvent.
 *
 * @param {string} type The newLog event
 * @param {array} args Data passed from event firer
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onNewLog = function(type, args, oSelf) {
    var logEntry = args[0];
    oSelf._buffer.push(logEntry);

    if (oSelf.logReaderEnabled === true && oSelf._timeout === null) {
        oSelf._timeout = setTimeout(function(){oSelf._printBuffer();}, 100);
    }
};

/**
 * Handles Logger's resetEvent.
 *
 * @param {string} type The click event
 * @param {array} args Data passed from event firer
 * @param {object} oSelf The log reader instance
 * @private
 */
YAHOO.widget.LogReader.prototype._onReset = function(type, args, oSelf) {
    oSelf._filterLogs();
};

