php-phpbb/phpBB/assets/javascript/installer.js

/**
 * Installer's AJAX frontend handler
 */

(function($) { // Avoid conflicts with other libraries

    'use strict';

    // Installer variables
    var pollTimer = null;
    var nextReadPosition = 0;
    var progressBarTriggered = false;
    var progressTimer = null;
    var currentProgress = 0;

    // Template related variables
    var $contentWrapper = $('.install-body').find('.main');

    // Intercept form submits
    interceptFormSubmit($('#install_install'));

    /**
     * Creates an XHR object
     *
     * jQuery cannot be used as the response is streamed, and
     * as of now, jQuery does not provide access to the response until
     * the connection is not closed.
     *
     * @return XMLHttpRequest|ActiveXObject
     */
    function createXhrObject() {
        var xhReq;

        if (window.XMLHttpRequest) {
            xhReq = new XMLHttpRequest();
        }
        else if (window.ActiveXObject) {
            xhReq = new ActiveXObject("Msxml2.XMLHTTP");
        }

        return xhReq;
    }

    /**
     * Displays error, warning and log messages
     *
     * @param type
     * @param messages
     */
    function addMessage(type, messages) {
        // Get message containers
        var $errorContainer = $('#error-container');
        var $warningContainer = $('#warning-container');
        var $logContainer = $('#log-container');

        var $title, $description, $msgElement, arraySize = messages.length;
        for (var i = 0; i < arraySize; i++) {
            $msgElement = $('<div />');
            $title = $(document.createElement('strong'));
            $title.text(messages[i].title);
            $msgElement.append($title);

            if (messages[i].hasOwnProperty('description')) {
                $description = $(document.createElement('p'));
                $description.text(messages[i].description);
                $msgElement.append($description);
            }

            switch (type) {
                case 'error':
                    $msgElement.addClass('errorbox');
                    $errorContainer.append($msgElement);
                    break;
                case 'warning':
                    $msgElement.addClass('warningbox');
                    $warningContainer.append($msgElement);
                    break;
                case 'log':
                    $msgElement.addClass('log');
                    $logContainer.append($msgElement);
                    break;
            }
        }
    }

    /**
     * Displays a form from the response
     *
     * @param formHtml
     */
    function addForm(formHtml) {
        var $formContainer = $('#content-container');
        $formContainer.html(formHtml);
        var $form = $('#install_install');
        interceptFormSubmit($form);
    }

    /**
     * Renders progress bar
     *
     * @param progressObject
     */
    function setProgress(progressObject) {
        var $statusText, $progressBar, $progressText, $progressFiller;

        if (progressObject.task_name.length) {
            if (!progressBarTriggered) {
                // Create progress bar
                var $contentContainer = $('#content-container');

                // Create progress bar elements
                $progressBar = $('<div />');
                $progressBar.attr('id', 'progress-bar');
                $progressText = $('<p />');
                $progressText.attr('id', 'progress-bar-text');
                $progressFiller = $('<span />');
                $progressFiller.attr('id', 'progress-bar-filler');

                $statusText = $('<p />');
                $statusText.attr('id', 'progress-status-text');

                $progressBar.append($progressFiller);
                $progressBar.append($progressText);

                $contentContainer.append($statusText);
                $contentContainer.append($progressBar);

                progressBarTriggered = true;
            } else {
                $statusText = $('#progress-status-text');
            }

            // Update progress bar
            $statusText.text(progressObject.task_name + '…');
            incrementProgressBar(Math.round(progressObject.task_num / progressObject.task_count * 100));
        }
    }

    /**
     * Parse messages from the response object
     *
     * @param messageJSON
     */
    function parseMessage(messageJSON) {
        $('#loading_indicator').css('display', 'none');

        var responseObject = JSON.parse(messageJSON);

        // Parse object
        if (responseObject.hasOwnProperty('errors')) {
            addMessage('error', responseObject.errors);
        }

        if (responseObject.hasOwnProperty('warnings')) {
            addMessage('warning', responseObject.warnings);
        }

        if (responseObject.hasOwnProperty('logs')) {
            addMessage('log', responseObject.logs);
        }

        if (responseObject.hasOwnProperty('form')) {
            addForm(responseObject.form);
        }

        if (responseObject.hasOwnProperty('progress')) {
            setProgress(responseObject.progress);
        }
    }

    /**
     * Process updates in streamed response
     *
     * @param xhReq   XHR object
     */
    function pollContent(xhReq) {
        var messages = xhReq.responseText;
        var msgSeparator = '}\n\n';
        var unprocessed, messageEndIndex, endOfMessageIndex, message;

        do {
            unprocessed = messages.substring(nextReadPosition);
            messageEndIndex = unprocessed.indexOf(msgSeparator);

            if (messageEndIndex !== -1) {
                endOfMessageIndex = messageEndIndex + msgSeparator.length;
                message = unprocessed.substring(0, endOfMessageIndex);
                parseMessage(message);
                nextReadPosition += endOfMessageIndex;
            }
        } while (messageEndIndex !== -1);

        if (xhReq.readyState === 4) {
            $('#loading_indicator').css('display', 'none');
            resetPolling();
        }
    }

    /**
     * Animates the progress bar
     *
     * @param $progressText
     * @param $progressFiller
     * @param progressLimit
     */
    function incrementFiller($progressText, $progressFiller, progressLimit) {
        currentProgress++;
        $progressText.text(currentProgress + '%');
        $progressFiller.css('width', currentProgress + '%');

        if (currentProgress >= progressLimit || currentProgress >= 100) {
            clearInterval(progressTimer);
        }
    }

    /**
     * Wrapper function for progress bar rendering and animating
     *
     * @param progressLimit
     */
    function incrementProgressBar(progressLimit) {
        var $progressFiller = $('#progress-bar-filler');
        var $progressText = $('#progress-bar-text');
        var progressStart = $progressFiller.width() / $progressFiller.offsetParent().width() * 100;
        currentProgress = Math.floor(progressStart);

        clearInterval(progressTimer);
        progressTimer = setInterval(function() {
            incrementFiller($progressText, $progressFiller, progressLimit);
        }, 10);
    }

    /**
     * Sets up timer for processing the streamed HTTP response
     *
     * @param xhReq
     */
    function startPolling(xhReq) {
        resetPolling();
        pollTimer = setInterval(function () {
            pollContent(xhReq);
        }, 500);
    }

    /**
     * Resets the polling timer
     */
    function resetPolling() {
        clearInterval(pollTimer);
        nextReadPosition = 0;
    }

    /**
     * Renders the AJAX UI layout
     */
    function setupAjaxLayout() {
        // Clear content
        $contentWrapper.html('');

        var $header = $('<div />');
        $header.attr('id', 'header-container');
        $contentWrapper.append($header);

        var $description = $('<div />');
        $description.attr('id', 'description-container');
        $contentWrapper.append($description);

        var $errorContainer = $('<div />');
        $errorContainer.attr('id', 'error-container');
        $contentWrapper.append($errorContainer);

        var $warningContainer = $('<div />');
        $warningContainer.attr('id', 'warning-container');
        $contentWrapper.append($warningContainer);

        var $installerContentWrapper = $('<div />');
        $installerContentWrapper.attr('id', 'content-container');
        $contentWrapper.append($installerContentWrapper);

        var $logContainer = $('<div />');
        $logContainer.attr('id', 'log-container');
        $contentWrapper.append($logContainer);

        var $spinner = $('<div />');
        $spinner.attr('id', 'loading_indicator');
        $spinner.html('&nbsp;');
        $contentWrapper.append($spinner);
    }

    function submitForm($form, $submitBtn) {
        $form.css('display', 'none');

        var xhReq = createXhrObject();
        xhReq.open('POST', $form.attr('action'), true);
        xhReq.setRequestHeader('X-Requested-With', 'XMLHttpRequest');
        xhReq.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
        xhReq.send(getFormFields($form, $submitBtn));

        // Clear content
        setupAjaxLayout();
        $('#loading_indicator').css('display', 'block');

        startPolling(xhReq);
    }

    /**
     * Add submit button to the POST information
     *
     * @param $form
     * @param $submitBtn
     *
     * @returns {*}
     */
    function getFormFields($form, $submitBtn) {
        var formData = $form.serialize();
        formData += ((formData.length) ? '&' : '') + encodeURIComponent($submitBtn.attr('name')) + '=';
        formData += encodeURIComponent($submitBtn.attr('value'));

        return formData;
    }

    /**
     * Intercept form submit events and determine the submit button used
     *
     * @param $form
     */
    function interceptFormSubmit($form) {
        if (!$form.length) {
            return;
        }

        $form.find(':submit').bind('click', function (event) {
            event.preventDefault();
            submitForm($form, $(this));
        });
    }
})(jQuery); // Avoid conflicts with other libraries