/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

WebInspector.PleaseWaitMessage = function()
{
    this.element = document.createElement("div");
    this.element.className = "please-wait-msg";
    this.element.textContent = WebInspector.UIString("Please wait\u2026");

    this.cancelButton = document.createElement("button");
    this.cancelButton.textContent = WebInspector.UIString("Cancel");
    this.cancelButton.addEventListener("click", this._cancelClicked.bind(this), false);
}

WebInspector.PleaseWaitMessage.prototype = {
    _cancelClicked: function()
    {
        if (this._cancelCallback) {
            var cancelCallback = this._cancelCallback;
            delete this._cancelCallback;
            cancelCallback();
        }
    },

    hide: function()
    {
        var instance = WebInspector.PleaseWaitMessage.prototype.instance;
        var message = instance.element;
        if (message.parentNode)
            message.parentNode.removeChild(message);
    },

    get instance()
    {
        if (!"_instance" in WebInspector.PleaseWaitMessage.prototype)
            WebInspector.PleaseWaitMessage.prototype._instance = new WebInspector.PleaseWaitMessage();
        return WebInspector.PleaseWaitMessage.prototype._instance;
    },

    show: function(element, cancelCallback)
    {
        var instance = WebInspector.PleaseWaitMessage.prototype.instance;
        var message = instance.element;
        if (message.parentNode === element)
            return;
        else if (message.parentNode)
            message.parentNode.removeChild(message);
        if (message.childNodes.length > 1)
            message.removeChild(instance.cancelButton);
        if (cancelCallback) {
            message.appendChild(instance.cancelButton);
            instance._cancelCallback = cancelCallback;
        }
        element.appendChild(message);
    },

    startAction: function(element, actionCallback, cancelCallback)
    {
        var instance = WebInspector.PleaseWaitMessage.prototype.instance;
        var message = instance.element;
        if (message.parentNode === element) {
            actionCallback();
            return;
        }
     
        function doAction()
        {
            try {
                actionCallback();
            } finally {
                if (message.parentNode)
                    message.parentNode.removeChild(message);
            }
        }

        WebInspector.PleaseWaitMessage.prototype.show(element, cancelCallback);
        setTimeout(doAction, 0);
    }
};