moodle/lib/form/dndupload.js
2012-06-15 14:48:02 +08:00

538 lines
19 KiB
JavaScript

// This file is part of Moodle - http://moodle.org/
//
// 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/>.
/**
* Javascript library for enableing a drag and drop upload interface
*
* @package moodlecore
* @subpackage form
* @copyright 2011 Davo Smith
* @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
*/
M.form_dndupload = {}
M.form_dndupload.init = function(Y, options) {
var dnduploadhelper = {
// YUI object.
Y: null,
// URL for upload requests
url: M.cfg.wwwroot + '/repository/repository_ajax.php?action=upload',
// options may include: itemid, acceptedtypes, maxfiles, maxbytes, clientid, repositoryid, author
options: {},
// itemid used for repository upload
itemid: null,
// accepted filetypes accepted by this form passed to repository
acceptedtypes: [],
// maximum number of files this form allows
maxfiles: 0,
// maximum size of files allowed in this form
maxbytes: 0,
// unqiue id of this form field used for html elements
clientid: '',
// upload repository id, used for upload
repositoryid: 0,
// container which holds the node which recieves drag events
container: null,
// filemanager element we are working with
filemanager: null,
// callback to filepicker element to refesh when uploaded
callback: null,
// Nasty hack to distinguish between dragenter(first entry),
// dragenter+dragleave(moving between child elements) and dragleave (leaving element)
entercount: 0,
pageentercount: 0,
/**
* Initalise the drag and drop upload interface
* Note: one and only one of options.filemanager and options.formcallback must be defined
*
* @param Y the YUI object
* @param object options {
* itemid: itemid used for repository upload in this form
* acceptdtypes: accepted filetypes by this form
* maxfiles: maximum number of files this form allows
* maxbytes: maximum size of files allowed in this form
* clientid: unqiue id of this form field used for html elements
* containerid: htmlid of container
* repositories: array of repository objects passed from filepicker
* filemanager: filemanager element we are working with
* formcallback: callback to filepicker element to refesh when uploaded
* }
*/
init: function(Y, options) {
this.Y = Y;
if (!this.browser_supported()) {
Y.one('body').addClass('dndnotsupported');
return; // Browser does not support the required functionality
}
Y.one('body').addClass('dndsupported');
// try and retrieve enabled upload repository
this.repositoryid = this.get_upload_repositoryid(options.repositories);
if (!this.repositoryid) {
return; // no upload repository is enabled to upload to
}
this.options = options;
this.acceptedtypes = options.acceptedtypes;
this.clientid = options.clientid;
this.maxfiles = options.maxfiles;
this.maxbytes = options.maxbytes;
this.itemid = options.itemid;
this.author = options.author;
this.container = this.Y.one('#'+options.containerid);
if (options.filemanager) {
// Needed to tell the filemanager to redraw when files uploaded
// and to check how many files are already uploaded
this.filemanager = options.filemanager;
} else if (options.formcallback) {
// Needed to tell the filepicker to update when a new
// file is uploaded
this.callback = options.formcallback;
} else {
if (M.cfg.developerdebug) {
alert('dndupload: Need to define either options.filemanager or options.formcallback');
}
return;
}
this.init_events();
this.init_page_events();
},
/**
* Check the browser has the required functionality
* @return true if browser supports drag/drop upload
*/
browser_supported: function() {
if (typeof FileReader == 'undefined') {
return false;
}
if (typeof FormData == 'undefined') {
return false;
}
return true;
},
/**
* Get upload repoistory from array of enabled repositories
*
* @param array repositories repository objects passed from filepicker
* @param returns int id of upload repository or false if not found
*/
get_upload_repositoryid: function(repositories) {
for (var i in repositories) {
if (repositories[i].type == "upload") {
return repositories[i].id;
}
}
return false;
},
/**
* Initialise drag events on node container, all events need
* to be processed for drag and drop to work
*/
init_events: function() {
this.Y.on('dragenter', this.drag_enter, this.container, this);
this.Y.on('dragleave', this.drag_leave, this.container, this);
this.Y.on('dragover', this.drag_over, this.container, this);
this.Y.on('drop', this.drop, this.container, this);
},
/**
* Initialise whole-page events (to show / hide the 'drop files here'
* message)
*/
init_page_events: function() {
this.Y.on('dragenter', this.drag_enter_page, 'body', this);
this.Y.on('dragleave', this.drag_leave_page, 'body', this);
},
/**
* Show the 'drop files here' message when file(s) are dragged
* onto the page
*/
drag_enter_page: function(e) {
if (!this.has_files(e) || this.reached_maxfiles()) {
return false;
}
this.pageentercount++;
if (this.pageentercount >= 2) {
this.pageentercount = 2;
return false;
}
this.show_drop_target();
return false;
},
/**
* Hide the 'drop files here' message when file(s) are dragged off
* the page again
*/
drag_leave_page: function(e) {
this.pageentercount--;
if (this.pageentercount == 1) {
return false;
}
this.pageentercount = 0;
this.hide_drop_target();
return false;
},
/**
* Check if the drag contents are valid and then call
* preventdefault / stoppropagation to let the browser know
* we will handle this drag/drop
*
* @param e event object
* @return boolean true if a valid file drag event
*/
check_drag: function(e, maxfilesalert) {
if (!this.has_files(e)) {
return false;
}
e.preventDefault();
e.stopPropagation();
if (this.reached_maxfiles()) {
if (typeof(maxfilesalert) != 'undefined' && maxfilesalert) {
alert(M.util.get_string('maxfilesreached', 'moodle', this.maxfiles));
}
return false;
}
return true;
},
/**
* Handle a dragenter event, highlight the destination node
* when a suitable drag event occurs
*/
drag_enter: function(e) {
if (!this.check_drag(e)) {
return true;
}
this.entercount++;
if (this.entercount >= 2) {
this.entercount = 2; // Just moved over a child element - nothing to do
return false;
}
// These lines are needed if the user has dragged something directly
// from application onto the 'fileupload' box, without crossing another
// part of the page first
this.pageentercount = 2;
this.show_drop_target();
this.show_upload_ready();
return false;
},
/**
* Handle a dragleave event, Remove the highlight if dragged from
* node
*/
drag_leave: function(e) {
if (!this.check_drag(e)) {
return true;
}
this.entercount--;
if (this.entercount == 1) {
return false; // Just moved over a child element - nothing to do
}
this.entercount = 0;
this.hide_upload_ready();
return false;
},
/**
* Handle a dragover event. Required to intercept to prevent the browser from
* handling the drag and drop event as normal
*/
drag_over: function(e) {
if (!this.check_drag(e)) {
return true;
}
return false;
},
/**
* Handle a drop event. Remove the highlight and then upload each
* of the files (until we reach the file limit, or run out of files)
*/
drop: function(e) {
if (!this.check_drag(e, true)) {
return true;
}
this.entercount = 0;
this.pageentercount = 0;
this.hide_upload_ready();
this.hide_drop_target();
var files = e._event.dataTransfer.files;
if (this.filemanager) {
var currentfilecount = this.filemanager.filecount;
if (((currentfilecount + files.length) > this.maxfiles) && (this.maxfiles != -1)) {
// TODO in case of overwrite we don't need it!
alert(M.util.get_string('maxfilesreached', 'moodle', this.maxfiles)); // TODO change to YUI
return false;
}
//this.show_progress_spinner();
var options = {
files:files,
options: this.options,
repositoryid: this.repositoryid,
callback:this.callback ? Y.bind('callback', this) : Y.bind('update_filemanager', this)
};
var uploader = new dnduploader(options);
uploader.doupload();
} else {
//this.show_progress_spinner();
if (files.length >= 1) {
options = {
files:[files[0]],
options: this.options,
repositoryid: this.repositoryid,
callback:this.callback ? Y.bind('callback', this) : Y.bind('update_filemanager', this)
};
uploader = new dnduploader(options);
uploader.doupload();
}
}
return false;
},
/**
* Check to see if the drag event has any files in it
*
* @param e event object
* @return boolean true if event has files
*/
has_files: function(e) {
var types = e._event.dataTransfer.types;
for (var i=0; i<types.length; i++) {
if (types[i] == 'Files') {
return true;
}
}
return false;
},
/**
* Check if reached the maximumum number of allowed files
*
* @return boolean true if reached maximum number of files
*/
reached_maxfiles: function() {
if (this.filemanager) {
if (this.filemanager.filecount >= this.maxfiles && this.maxfiles != -1) {
return true;
}
}
return false;
},
/**
* Highlight the area where files could be dropped
*/
show_drop_target: function() {
this.container.addClass('dndupload-ready');
},
hide_drop_target: function() {
this.container.removeClass('dndupload-ready');
},
/**
* Highlight the destination node (ready to drop)
*/
show_upload_ready: function() {
this.container.addClass('dndupload-over');
},
/**
* Remove highlight on destination node
*/
hide_upload_ready: function() {
this.container.removeClass('dndupload-over');
},
/**
* Display a progress spinner in the destination node
*/
show_progress_spinner: function() {
this.container.addClass('dndupload-uploading');
},
/**
* Remove progress spinner in the destination node
*/
hide_progress_spinner: function() {
this.container.removeClass('dndupload-uploading');
},
/**
* Tell the attached filemanager element (if any) to refresh on file
* upload
*/
update_filemanager: function() {
if (this.filemanager) {
// update the filemanager that we've uploaded the files
this.filemanager.filepicker_callback();
}
}
};
var dnduploader = function(options) {
dnduploader.superclass.constructor.apply(this, arguments);
};
Y.extend(dnduploader, Y.Base, {
api: M.cfg.wwwroot+'/repository/repository_ajax.php',
options: {},
callback: null,
files: null,
repositoryid: 0,
processedfiles: 0,
initializer: function(params) {
this.options = params.options;
this.repositoryid = params.repositoryid;
this.callback = params.callback;
this.files = params.files; // TODO make copy?
},
doupload: function(lastresult) {
console.log('doupload : '+this.processedfiles);
if (this.files && this.files.length > this.processedfiles) {
console.log('uploading file');
console.log(this.files[this.processedfiles])
this.upload_file(this.files[this.processedfiles]);
} else {
this.uploadfinished(lastresult);
}
},
uploadfinished: function(lastresult) {
console.log('upload finished')
this.callback(lastresult);
},
add_error: function(text, errorlevel) {
// TODO
console.log(text);
},
/**
* Upload a single file via an AJAX call to the 'upload' repository
*/
upload_file: function(file) {
if (this.options.maxbytes > 0 && file.size > this.options.maxbytes) {
// Check filesize before attempting to upload
this.add_error(M.util.get_string('uploadformlimit', 'moodle')+"\n'"+file.name+"'"); //TODO proper string
return false;
}
// This would be an ideal place to use the Y.io function
// however, this does not support data encoded using the
// FormData object, which is needed to transfer data from
// the DataTransfer object into an XMLHTTPRequest
// This can be converted when the YUI issue has been integrated:
// http://yuilibrary.com/projects/yui3/ticket/2531274
var xhr = new XMLHttpRequest();
var self = this;
xhr.onreadystatechange = function() { // Process the server response
if (xhr.readyState == 4) {
if (xhr.status == 200) {
console.log(xhr.responseText)
var result = JSON.parse(xhr.responseText);
if (result) {
console.log(result)
if (result.error) {
self.add_error(result.error); // TODO add filename?
} else {
// Only update the filepicker if there were no errors
if (result.event == 'fileexists') {
// Do not worry about this, as we only care about the last
// file uploaded, with the filepicker
result.file = result.newfile.filename;
result.url = result.newfile.url;
}
result.client_id = self.options.clientid;
}
}
self.processedfiles++;
self.doupload(result); // continue uploading
} else {
self.add_error(M.util.get_string('serverconnection', 'error'));
this.uploadfinished();
}
}
};
// Prepare the data to send
var formdata = new FormData();
formdata.append('action', 'upload');
formdata.append('repo_upload_file', file); // The FormData class allows us to attach a file
formdata.append('sesskey', M.cfg.sesskey);
formdata.append('repo_id', this.repositoryid);
formdata.append('itemid', this.options.itemid);
if (this.options.author) {
formdata.append('author', this.options.author);
}
if (this.options.filemanager) { // Filepickers do not have folders
formdata.append('savepath', this.options.filemanager.currentpath);
}
if (this.options.acceptedtypes.constructor == Array) { // TODO what is this???
for (var i=0; i<this.options.acceptedtypes.length; i++) {
formdata.append('accepted_types[]', this.options.acceptedtypes[i]);
}
} else {
formdata.append('accepted_types[]', this.options.acceptedtypes);
}
// Send the file & required details
xhr.open("POST", this.api, true);
console.log('formdata')
console.log(formdata)
xhr.send(formdata);
return true;
}
});
dnduploadhelper.init(Y, options);
};