[moodle.git] / files / renderer.php

<?php
///////////////////////////////////////////////////////////////////////////
//                                                                       //
// This file is part of Moodle - http://moodle.org/                      //
// Moodle - Modular Object-Oriented Dynamic Learning Environment         //
//                                                                       //
// Moodle is free software: you can redistribute it and/or modify        //
// it under the terms of the GNU General Public License as published by  //
// the Free Software Foundation, either version 3 of the License, or     //
// (at your option) any later version.                                   //
//                                                                       //
// Moodle is distributed in the hope that it will be useful,             //
// but WITHOUT ANY WARRANTY; without even the implied warranty of        //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         //
// GNU General Public License for more details.                          //
//                                                                       //
// You should have received a copy of the GNU General Public License     //
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.       //
//                                                                       //
///////////////////////////////////////////////////////////////////////////

defined('MOODLE_INTERNAL') || die();

/**
 * Rendering of files viewer related widgets.
 * @package   core
 * @subpackage file
 * @copyright 2010 Dongsheng Cai
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 * @since     Moodle 2.0
 */

/**
 * File browser render
 *
 * @copyright 2010 Dongsheng Cai
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 * @since     Moodle 2.0
 */
class core_files_renderer extends plugin_renderer_base {

    public function files_tree_viewer(file_info $file_info, array $options = null) {
        $tree = new files_tree_viewer($file_info, $options);
        return $this->render($tree);
    }

    public function render_files_tree_viewer(files_tree_viewer $tree) {
        $html = $this->output->heading_with_help(get_string('coursefiles'), 'courselegacyfiles', 'moodle');

        $html .= $this->output->container_start('coursefilesbreadcrumb');
        foreach($tree->path as $path) {
            $html .= $path;
            $html .= ' / ';
        }
        $html .= $this->output->container_end();

        $html .= $this->output->box_start();
        $table = new html_table();
        $table->head = array(get_string('filename', 'backup'), get_string('size'), get_string('modified'));
        $table->align = array('left', 'right', 'right');
        $table->width = '100%';
        $table->data = array();

        foreach ($tree->tree as $file) {
            if (!empty($file['isdir'])) {
                $table->data[] = array(
                    html_writer::link($file['url'], $this->output->pix_icon('f/folder', 'icon') . ' ' . $file['filename']),
                    '',
                    $file['filedate'],
                    );
            } else {
                $table->data[] = array(
                    html_writer::link($file['url'], $this->output->pix_icon('f/'.mimeinfo('icon', $file['filename']), get_string('icon')) . ' ' . $file['filename']),
                    $file['filesize'],
                    $file['filedate'],
                    );
            }
        }

        $html .= html_writer::table($table);
        $html .= $this->output->single_button(new moodle_url('/files/coursefilesedit.php', array('contextid'=>$tree->context->id)), get_string('coursefilesedit'), 'get');
        $html .= $this->output->box_end();
        return $html;
    }

    /**
     * Prints the file manager and initializes all necessary libraries
     *
     * <pre>
     * $fm = new form_filemanager($options);
     * $output = get_renderer('core', 'files');
     * echo $output->render($fm);
     * </pre>
     *
     * @param form_filemanager $fm File manager to render
     * @return string HTML fragment
     */
    public function render_form_filemanager($fm) {
        static $filemanagertemplateloaded;
        $html = $this->fm_print_generallayout($fm);
        $module = array(
            'name'=>'form_filemanager',
            'fullpath'=>'/lib/form/filemanager.js',
            'requires' => array('core_filepicker', 'base', 'io-base', 'node', 'json', 'yui2-button', 'yui2-container', 'yui2-layout', 'yui2-menu', 'yui2-treeview', 'core_dndupload'),
            'strings' => array(array('loading', 'repository'), array('nomorefiles', 'repository'), array('confirmdeletefile', 'repository'),
                 array('add', 'repository'), array('accessiblefilepicker', 'repository'), array('move', 'moodle'),
                 array('cancel', 'moodle'), array('download', 'moodle'), array('ok', 'moodle'),
                 array('emptylist', 'repository'), array('nofilesattached', 'repository'), array('entername', 'repository'), array('enternewname', 'repository'),
                 array('zip', 'editor'), array('unzip', 'moodle'), array('rename', 'moodle'), array('delete', 'moodle'),
                 array('cannotdeletefile', 'error'), array('confirmdeletefile', 'repository'),
                 array('nopathselected', 'repository'), array('popupblockeddownload', 'repository'),
                 array('draftareanofiles', 'repository'), array('path', 'moodle'), array('setmainfile', 'repository'),
                 array('moving', 'repository'), array('files', 'moodle'), array('serverconnection', 'error')
            )
        );
        if (empty($filemanagertemplateloaded)) {
            $filemanagertemplateloaded = true;
            $this->page->requires->js_init_call('M.form_filemanager.set_templates',
                    array(array(
                        'onefile' => '___fullname___ ___action___'
                    )), true, $module);
        }
        $this->page->requires->js_init_call('M.form_filemanager.init', array($fm->options), true, $module);

        // non javascript file manager
        $html .= '<noscript>';
        $html .= "<div><object type='text/html' data='".$fm->get_nonjsurl()."' height='160' width='600' style='border:1px solid #000'></object></div>";
        $html .= '</noscript>';


        return $html;
    }

    /**
     * Returns html for displaying one file manager
     *
     * The main element in HTML must have id="filemanager-{$client_id}" and
     * class="filemanager fm-loading";
     * After all necessary code on the page (both html and javascript) is loaded,
     * the class fm-loading will be removed and added class fm-loaded;
     * The main element (class=filemanager) will be assigned the following classes:
     * 'fm-maxfiles' - when filemanager has maximum allowed number of files;
     * 'fm-nofiles' - when filemanager has no files at all (although there might be folders);
     * 'fm-noitems' - when current view (folder) has no items - neither files nor folders;
     * 'fm-updating' - when current view is being updated (usually means that loading icon is to be displayed);
     * 'fm-nomkdir' - when 'Make folder' action is unavailable (empty($fm->options->subdirs) == true)
     *
     * Element with class 'filemanager-container' will be holding evens for dnd upload (dragover, etc.).
     * It will have class:
     * 'dndupload-ready' - when a file is being dragged over the browser
     * 'dndupload-over' - when file is being dragged over this filepicker (additional to 'dndupload-ready')
     * 'dndupload-uploading' - during the upload process (note that after dnd upload process is
     * over, the file manager will refresh the files list and therefore will have for a while class
     * fm-updating. Both waiting processes should look similar so the images don't jump for user)
     *
     * If browser supports Drag-and-drop, the body element will have class 'dndsupported',
     * otherwise - 'dndnotsupported';
     *
     * Element with class 'fm-filelist' will be populated with files list;
     * Element with class 'fm-breadcrumb' will be populated with the path or have class 'fm-empty' when empty;
     * Element with class 'fm-btn-add' will hold onclick event for adding a file (opening filepicker);
     * Element with class 'fm-btn-mkdir' will hold onclick event for adding new folder;
     * Element with class 'fm-btn-download' will hold onclick event for download action;
     *
     * @param form_filemanager $fm
     * @return string
     */
    private function fm_print_generallayout($fm) {
        global $OUTPUT;
        $options = $fm->options;
        $client_id = $options->client_id;
        $straddfile  = get_string('addfile', 'repository');
        $strmakedir  = get_string('makeafolder', 'moodle');
        $strdownload = get_string('downloadfolder', 'repository');
        $strloading  = get_string('loading', 'repository');
        $strnofilesattached = get_string('nofilesattached', 'repository');
        $strdroptoupload = get_string('droptoupload', 'moodle');
        $icon_progress = $OUTPUT->pix_icon('i/loading_small', $strloading).'';
        $restrictions = $this->fm_print_restrictions($fm);
        $strdndenabled = get_string('dndenabled_insentence', 'moodle').$OUTPUT->help_icon('dndenabled');
        $strdndenabledinbox = get_string('dndenabled_inbox', 'moodle');
        $loading = get_string('loading', 'repository');

        $html .= <<<FMHTML
<div id="filemanager-{$client_id}" class="filemanager fm-loading">
    <div class="filemanager-loading mdl-align">{$icon_progress}</div>
    <div class="fm-breadcrumb"></div>
    <div class="filemanager-toolbar">
        <input type="button" class="fm-btn-add" value="{$straddfile}" />
        <input type="button" class="fm-btn-mkdir" value="{$strmakedir}" />
        <input type="button" class="fm-btn-download" value="{$strdownload}" />
        {$restrictions}
        <span class="dndupload-message"> - $strdndenabled </span>
    </div>
    <div class="filemanager-container" >
        <ul class="fm-filelist"></ul>
        <div class="fm-empty-container mdl-align">{$strnofilesattached}
            <span class="dndupload-message">{$strdndenabledinbox}</span>
        </div>
        <div class="dndupload-target">{$strdroptoupload}</div>
        <div class="dndupload-uploadinprogress">{$icon_progress}</div>
        <div class="filemanager-updating">{$icon_progress}</div>
    </div>
</div>
<div class="clearer"></div>
FMHTML;
        return $html;
    }

    /**
     * Displays restrictions for the file manager
     *
     * @param form_filemanager $fm
     * @return string
     */
    private function fm_print_restrictions($fm) {
        $maxbytes = display_size($fm->options->maxbytes);
        if (empty($options->maxfiles) || $options->maxfiles == -1) {
            $maxsize = get_string('maxfilesize', 'moodle', $maxbytes);
            //$string['maxfilesize'] = 'Maximum size for new files: {$a}';
        } else {
            $strparam = (object)array('size' => $maxbytes, 'attachments' => $options->maxfiles);
            $maxsize = get_string('maxsizeandattachments', 'moodle', $strparam);
            //$string['maxsizeandattachments'] = 'Maximum size for new files: {$a->size}, maximum attachments: {$a->attachments}';
        }
        // TODO MDL-32020 also should say about 'File types accepted'
        return '<span>'. $maxsize. '</span>';
    }

    /**
     * Template for FilePicker with general layout (not QuickUpload).
     *
     * Must have one top element containing everything else (recommended <div class="file-picker">),
     * CSS for this element must define width and height of the filepicker window. Or CSS must
     * define min-width, max-width, min-height and max-height and in this case the filepicker
     * window will be resizeable;
     *
     * Element with class 'fp-viewbar' will have the class 'enabled' or 'disabled' when view mode
     * can be changed or not;
     * Inside element with class 'fp-viewbar' there are expected elements with classes
     * 'fp-vb-icons', 'fp-vb-tree' and 'fp-vb-details'. They will handle onclick events to switch
     * between the view modes, the last clicked element will have the class 'checked';
     *
     * Element with class 'fp-repo' is a template for displaying one repository. Other repositories
     * will be attached as siblings (classes first/last/even/odd will be added respectfully).
     * The currently selected repostory will have class 'active'. Contents of element with class
     * 'fp-repo-name' will be replaced with repository name, source of image with class
     * 'fp-repo-icon' will be replaced with repository icon;
     *
     * Element with class 'fp-content' is obligatory and will hold the current contents;
     *
     * Element with class 'fp-paging' will contain page navigation (will be deprecated soon);
     *
     * Element with class 'fp-path-folder' will contain template for one folder in path toolbar.
     * It will hold mouse click event and will be assigned classes first/last/even/odd respectfully.
     * The content of element with class 'fp-path-folder-name' will be substituted with folder name;
     * Parent element will receive class 'empty' when there are no folders to be displayed;
     *
     * Element with class 'fp-toolbar' will have class 'empty' if all 'Back', 'Search', 'Refresh',
     * 'Logout', 'Manage' and 'Help' are unavailable for this repo;
     *
     * Inside fp-toolbar there are expected elements with classes fp-tb-back, fp-tb-search,
     * fp-tb-refresh, fp-tb-logout, fp-tb-manage and fp-tb-help. Each of them will have
     * class 'enabled' or 'disabled' if particular repository has this functionality.
     * Element with class 'fp-tb-search' must contain empty form inside, it's contents will
     * be substituted with the search form returned by repository (in the most cases it
     * is generated with template core_repository_renderer::repository_default_searchform);
     * Other elements must have either <a> or <button> element inside, it will hold onclick
     * event for corresponding action; labels for fp-tb-back and fp-tb-logout may be
     * replaced with those specified by repository;
     *
     * @return string
     */
    private function fp_js_template_generallayout() {
        $rv = '
<div class="file-picker fp-generallayout">
  <div>
    <div class="{!}fp-viewbar" style="float:none;">
       <span class=""><button class="{!}fp-vb-icons">'.get_string('iconview', 'repository').'</button></span>
       <span class=""><button class="{!}fp-vb-tree">'.get_string('listview', 'repository').'</button></span>
       <span class=""><button class="{!}fp-vb-details">'.get_string('detailview', 'repository').'</button></span>
    </div>
  </div>
  <div style="vertical-align:top;">
    <div style="width:200px;height:400px;display:inline-block;overflow:auto;">
      <ul class="fp-list">
        <li class="{!}fp-repo"><img class="{!}fp-repo-icon" width="16" height="16" />&nbsp;<span class="{!}fp-repo-name"></span></li>
      </ul>
    </div>
    <div style="width:480px;height:400px;display:inline-block;vertical-align:top;">
      <div class="{!}fp-toolbar">
        <div class="{!}fp-tb-back"><a>'.get_string('back', 'repository').'</a></div>
        <div class="{!}fp-tb-search">
          <img src="'.$this->pix_url('a/search').'" />
          <form/>
        </div>
        <div class="{!}fp-tb-refresh"><a><img src="'.$this->pix_url('a/refresh').'" />'.get_string('refresh', 'repository').'</a></div>
        <div class="{!}fp-tb-logout"><img src="'.$this->pix_url('a/logout').'" /><a></a></div>
        <div class="{!}fp-tb-manage"><a><img src="'.$this->pix_url('a/setting').'" /> '.get_string('manageurl', 'repository').'</a></div>
        <div class="{!}fp-tb-help"><a><img src="'.$this->pix_url('a/help').'" /> '.get_string('help').'</a></div>
      </div>
      <div class="fp-pathbar" style="background:#ddffdd">
        <span class="{!}fp-path-folder"><a class="{!}fp-path-folder-name"></a><span>/</span></span>
      </div>
      <div class="{!}fp-content"></div>
    </div>
  </div>
</div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for displaying list of files in 'icon view' mode.
     *
     * Element with class 'fp-file' is a template for displaying one file and indicates a place
     * where files shall be output. It also will hold mouse events (click, over, out, etc.);
     *
     * the element with class 'fp-thumbnail' will be resized to the repository thumbnail size
     * (both width and height, unless min-width and/or min-height is set in CSS) and the content of
     * an element will be replaced with an appropriate img;
     *
     * the width of element with class 'fp-filename' will be set to the repository thumbnail width
     * (unless min-width is set in css) and the content of an element will be replaced with filename
     * supplied by repository;
     *
     * @return string
     */
    private function fp_js_template_iconview() {
        $rv = '<div class="fp-iconview">
<div class="{!}fp-file">
    <div class="{!}fp-thumbnail"></div>
    <div class="{!}fp-filename"></div>
</div>
            </div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for displaying file name in 'table view' and 'tree view' modes.
     *
     * content of the element with class 'fp-icon' will be replaced with an appropriate img;
     *
     * content of element with class 'fp-filename' will be replaced with filename supplied by
     * repository;
     *
     * Note that tree view and table view are the YUI widgets and therefore there are no
     * other templates. The widgets will be wrapped in <div> with class fp-treeview or
     * fp-tableview (respectfully).
     *
     * @return string
     */
    private function fp_js_template_listfilename() {
        $rv = '<span class="{!}fp-icon"></span> <span class="{!}fp-filename"></span>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for displaying link/loading progress for fetching of the next page
     *
     * This text is added to .fp-content AFTER .fp-iconview/.fp-treeview/.fp-tableview
     *
     * Must have one parent element with class 'fp-nextpage'. It will be assigned additional
     * class 'loading' during loading of the next page (it is recommended that in this case the link
     * becomes unavailable). Also must contain one element <a> or <button> that will hold
     * onclick event for displaying of the next page. The event will be triggered automatically
     * when user scrolls to this link.
     *
     * @return string
     */
    private function fp_js_template_nextpage() {
        $rv = '<div class="{!}fp-nextpage">
  <div class="fp-nextpage-link"><a href="#">'.get_string('more').'</a></div>
  <div class="fp-nextpage-loading">
    <img src="'.$this->pix_url('i/loading').'" />
    <p>'.get_string('loading', 'repository').'</p>
  </div>
</div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * Template for window appearing to select a file.
     *
     * All content must be enclosed in an element with class 'fp-select', CSS for this class
     * must define width and height of the window;
     *
     * Thumbnail image will be added as content to the element with class 'fp-thumbnail';
     *
     * Inside the window the elements with the following classnames must be present:
     * 'fp-saveas', 'fp-linkexternal', 'fp-setauthor', 'fp-setlicense'. Inside each of them must have
     * one input element (or select in case of fp-setlicense). They may also have labels.
     * The elements will be assign with class 'uneditable' and input/select element will become
     * disabled if they are not applicable for the particular file;
     *
     * There may be present elements with classes 'fp-datemodified', 'fp-datecreated', 'fp-size',
     * 'fp-license', 'fp-author'. They will receive additional class 'fp-unknown' if information
     * is unavailable. If there is information available, the content of embedded element
     * with class 'fp-value' will be substituted with the value;
     *
     * Elements with classes 'fp-select-confirm' and 'fp-select-cancel' will hold corresponding
     * onclick events;
     *
     * When confirm button is pressed and file is being selected, the top element receives
     * additional class 'loading'. It is removed when response from server is received.
     *
     * @return string
     */
    private function fp_js_template_selectlayout() {
        $rv = '<div class="{!}fp-select">
<div class="fp-select-loading">
<img src="'.$this->pix_url('i/loading').'" />
<p>'.get_string('loading', 'repository').'</p>
</div>
<form>
<p class="{!}fp-thumbnail"></p>
<table width="100%">
<tr class="{!}fp-saveas"><td class="mdl-right"><label>'.get_string('saveas', 'repository').'</label>:</td>
<td class="mdl-left"><input type="text"/></td></tr>
<tr class="{!}fp-linkexternal"><td></td>
<td class="mdl-left"><input type="checkbox"/><label>'.get_string('linkexternal', 'repository').'</label></td></tr>
<tr class="{!}fp-setauthor"><td class="mdl-right"><label>'.get_string('author', 'repository').'</label>:</td>
<td class="mdl-left"><input type="text" /></td></tr>
<tr class="{!}fp-setlicense"><td class="mdl-right"><label>'.get_string('chooselicense', 'repository').'</label>:</td>
<td class="mdl-left"><select></select></td></tr>
</table>
<p><button class="{!}fp-select-confirm" >'.get_string('getfile', 'repository').'</button>
<button class="{!}fp-select-cancel" >'.get_string('cancel').'</button></p>
</form>
<div class="{!}fp-datemodified">'.get_string('lastmodified', 'moodle').': <span class="fp-value"/></div>
<div class="{!}fp-datecreated">'.get_string('datecreated', 'repository').': <span class="fp-value"/></div>
<div class="{!}fp-size">'.get_string('size', 'repository').': <span class="fp-value"/></div>
<div class="{!}fp-license">'.get_string('license', 'moodle').': <span class="fp-value"/></div>
<div class="{!}fp-author">'.get_string('author', 'repository').': <span class="fp-value"/></div>
<div class="{!}fp-dimensions">'.get_string('dimensions', 'repository').': <span class="fp-value"/></div>
</div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for 'Upload file' repository
     *
     * Content to display when user chooses 'Upload file' repository (will be nested inside
     * element with class 'fp-content').
     *
     * Must contain form (enctype="multipart/form-data" method="POST")
     *
     * The elements with the following classnames must be present:
     * 'fp-file', 'fp-saveas', 'fp-setauthor', 'fp-setlicense'. Inside each of them must have
     * one input element (or select in case of fp-setlicense). They may also have labels.
     *
     * Element with class 'fp-upload-btn' will hold onclick event for uploading the file;
     *
     * Please note that some fields may be hidden using CSS if this is part of quickupload form
     *
     * @return string
     */
    private function fp_js_template_uploadform() {
        $rv = '<div class="fp-upload-form mdl-align">
<form enctype="multipart/form-data" method="POST">
  <table width="100%">
    <tr class="{!}fp-file">
      <td class="mdl-right"><label>'.get_string('attachment', 'repository').'</label>:</td>
      <td class="mdl-left"><input type="file"/></td>
    </tr>
    <tr class="{!}fp-saveas">
      <td class="mdl-right"><label>'.get_string('saveas', 'repository').'</label>:</td>
      <td class="mdl-left"><input type="text"/></td>
    </tr>
    <tr class="{!}fp-setauthor">
      <td class="mdl-right"><label>'.get_string('author', 'repository').'</label>:</td>
      <td class="mdl-left"><input type="text"/></td>
    </tr>
    <tr class="{!}fp-setlicense">
      <td class="mdl-right"><label>'.get_string('chooselicense', 'repository').'</label>:</td>
      <td class="mdl-left"><select/></td>
    </tr>
  </table>
</form>
<div><button class="{!}fp-upload-btn">'.get_string('upload', 'repository').'</button></div>
</div> ';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template to display during loading process (inside element with class 'fp-content').
     *
     * @return string
     */
    private function fp_js_template_loading() {
        return '<div style="text-align:center">
<img src="'.$this->pix_url('i/loading').'" />
<p>'.get_string('loading', 'repository').'</p>
</div>';
    }

    /**
     * FilePicker JS template for error (inside element with class 'fp-content').
     *
     * must have element with class 'fp-error', its content will be replaced with error text
     * and the error code will be assigned as additional class to this element
     * used errors: invalidjson, nofilesavailable, norepositoriesavailable
     *
     * @return string
     */
    private function fp_js_template_error() {
        $rv = '<div class="{!}fp-error" />';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for error/info message displayed as a separate popup window.
     *
     * Must be wrapped in an element with class 'fp-msg', CSS for this element must define
     * width and height of the window. It will be assigned with an additional class 'fp-msg-error'
     * or 'fp-msg-info' depending on message type;
     *
     * content of element with class 'fp-msg-text' will be replaced with error/info text;
     *
     * element with class 'fp-msg-butok' will hold onclick event
     *
     * @return string
     */
    private function fp_js_template_message() {
        $rv = '<div class="{!}fp-msg">
                    <div class="{!}fp-msg-text"></div>
                    <div><button class="{!}fp-msg-butok">'.get_string('ok').'</button></div>
                </div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for popup dialogue window asking for action when file with the same name already exists.
     *
     * Must be wrapped in an element with class 'fp-dlg', CSS for this element must define width
     * and height of the window;
     *
     * content of element with class 'fp-dlg-text' will be replaced with dialog text;
     * elements with classes 'fp-dlg-butoverwrite', 'fp-dlg-butrename' and 'fp-dlg-butcancel' will
     * hold onclick events;
     *
     * content of element with class 'fp-dlg-butrename' will be substituted with appropriate string
     * (Note that it may have long text)
     *
     * @return string
     */
    private function fp_js_template_processexistingfile() {
        $rv = '<div class="{!}fp-dlg"><div class="{!}fp-dlg-text"></div>
<div class="fp-dlg-but"><button class="{!}fp-dlg-butoverwrite" >'.get_string('overwrite', 'repository').'</button></div>
<div class="fp-dlg-but"><button class="{!}fp-dlg-butrename" /></div>
<div class="fp-dlg-but"><button class="{!}fp-dlg-butcancel" >'.get_string('cancel').'</button></div>
</div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * FilePicker JS template for repository login form including templates for each element type
     *
     * Must contain one <form> element with templates for different input types inside:
     * Elements with classes 'fp-login-popup', 'fp-login-textarea', 'fp-login-select' and
     * 'fp-login-input' are templates for displaying respective login form elements. Inside
     * there must be exactly one element with type <button>, <textarea>, <select> or <input>
     * (i.e. fp-login-popup should have <button>, fp-login-textarea should have <textarea>, etc.);
     * They may also contain the <label> element and it's content will be substituted with
     * label;
     *
     * You can also define elements with classes 'fp-login-checkbox', 'fp-login-text'
     * but if they are not found, 'fp-login-input' will be used;
     *
     * Element with class 'fp-login-radiogroup' will be used for group of radio inputs. Inside
     * it should hava a template for one radio input (with class 'fp-login-radio');
     *
     * Element with class 'fp-login-submit' will hold on click mouse event (form submission). It
     * will be removed if at least one popup element is present;
     *
     * @return string
     */
    private function fp_js_template_loginform() {
        $rv = '
<div class="fp-login-form">
  <form>
    <table width="100%">
      <tr class="{!}fp-login-popup">
        <td colspan="2">
          <label>'.get_string('popup', 'repository').'</label>
          <p class="fp-popup"><button class="{!}fp-login-popup-but">'.get_string('login', 'repository').'</button></p>
        </td>
      </tr>
      <tr class="{!}fp-login-textarea">
        <td colspan="2"><p><textarea></textarea></p></td>
      </tr>
      <tr class="{!}fp-login-select">
        <td align="right"><label></label></td>
        <td align="left"><select></select></td>
      </tr>
      <tr class="{!}fp-login-input">
        <td align="right" width="30%" valign="center"><label /></td>
        <td align="left"><input/></td>
      </tr>
      <tr class="{!}fp-login-radiogroup">
        <td align="right" width="30%" valign="top"><label /></td>
        <td align="left" valign="top">
          <p class="{!}fp-login-radio"><input /> <label /></p>
        </td>
      </tr>
    </table>
    <p><button class="{!}fp-login-submit">'.get_string('submit', 'repository').'</button></p>
  </form>
</div>';
        return preg_replace('/\{\!\}/', '', $rv);
    }

    /**
     * Returns all FilePicker JavaScript templates as an array.
     *
     * @return array
     */
    public function filepicker_js_templates() {
        $class_methods = get_class_methods($this);
        $templates = array();
        foreach ($class_methods as $method_name) {
            if (preg_match('/^fp_js_template_(.*)$/', $method_name, $matches))
            $templates[$matches[1]] = $this->$method_name();
        }
        return $templates;
    }

    /**
     * Returns HTML for default repository searchform to be passed to Filepicker
     *
     * This will be used as contents for search form defined in generallayout template
     * (form with id {TOOLSEARCHID}).
     * Default contents is one text input field with name="s"
     */
    public function repository_default_searchform() {
        $str = '<label>'.get_string('keyword', 'repository').': </label><br/><input name="s" value="" /><br/>';
        return $str;
    }
}

/**
 * Data structure representing a general moodle file tree viewer
 *
 * @copyright 2010 Dongsheng Cai
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 * @since     Moodle 2.0
 */
class files_tree_viewer implements renderable {
    public $tree;
    public $path;
    public $context;

    /**
     * Constructor of moodle_file_tree_viewer class
     * @param file_info $file_info
     * @param array $options
     */
    public function __construct(file_info $file_info, array $options = null) {
        global $CFG;

        //note: this MUST NOT use get_file_storage() !!!!!!!!!!!!!!!!!!!!!!!!!!!!
        $this->options = (array)$options;
        $this->context = $options['context'];

        $this->tree = array();
        $children = $file_info->get_children();
        $current_file_params = $file_info->get_params();
        $parent_info = $file_info->get_parent();
        $level = $parent_info;
        $this->path = array();
        while ($level) {
            $params = $level->get_params();
            $context = get_context_instance_by_id($params['contextid']);
            // $this->context is current context
            if ($context->id != $this->context->id or empty($params['filearea'])) {
                break;
            }
            // unset unused parameters
            unset($params['component']);
            unset($params['filearea']);
            unset($params['filename']);
            unset($params['itemid']);
            $url = new moodle_url('/files/index.php', $params);
            $this->path[] = html_writer::link($url, $level->get_visible_name());
            $level = $level->get_parent();
        }
        $this->path = array_reverse($this->path);
        if ($current_file_params['filepath'] != '/') {
            $this->path[] = $file_info->get_visible_name();
        }

        foreach ($children as $child) {
            $filedate = $child->get_timemodified();
            $filesize = $child->get_filesize();
            $mimetype = $child->get_mimetype();
            $params = $child->get_params();
            unset($params['component']);
            unset($params['filearea']);
            unset($params['filename']);
            unset($params['itemid']);
            $fileitem = array(
                    'params'   => $params,
                    'filename' => $child->get_visible_name(),
                    'filedate' => $filedate ? userdate($filedate) : '',
                    'filesize' => $filesize ? display_size($filesize) : ''
                    );
            $url = new moodle_url('/files/index.php', $params);
            if ($child->is_directory()) {
                $fileitem['isdir'] = true;
                $fileitem['url'] = $url->out(false);
            } else {
                $fileitem['url'] = $child->get_url();
            }
            $this->tree[] = $fileitem;
        }
    }
}