/lenasys/trunk

/*

 * Default text - jQuery plugin for html5 dragging files from desktop to browser

 *

 * Author: Weixi Yen

 *

 * Email: [Firstname][Lastname]@gmail.com

 * 

 * Copyright (c) 2010 Resopollution

 * 

 * Licensed under the MIT license:

 *   http://www.opensource.org/licenses/mit-license.php

 *

 * Project home:

 *   http://www.github.com/weixiyen/jquery-filedrop

 *

 * Version:  0.1.0

 *

 * Features:

 *      Allows sending of extra parameters with file.

 *      Works with Firefox 3.6+

 *      Future-compliant with HTML5 spec (will work with Webkit browsers and IE9)

 * Usage:

 * 	See README at project homepage

 *

 */

(function($){

	jQuery.event.props.push("dataTransfer");

	var opts = {},

		default_opts = {

			url: '',

			refresh: 1000,

			paramname: 'userfile',

			maxfiles: 25,

			maxfilesize: 1, // MBs

			data: {},

			drop: empty,

			dragEnter: empty,

			dragOver: empty,

			dragLeave: empty,

			docEnter: empty,

			docOver: empty,

			docLeave: empty,

			beforeEach: empty,

			afterAll: empty,

			rename: empty,

			error: function(err, file, i){alert(err);},

			uploadStarted: empty,

			uploadFinished: empty,

			progressUpdated: empty,

			speedUpdated: empty

		},

		errors = ["BrowserNotSupported", "TooManyFiles", "FileTooLarge"],

		doc_leave_timer,

		stop_loop = false,

		files_count = 0,

		files;

	$.fn.filedrop = function(options) {

		opts = $.extend( {}, default_opts, options );

		this.bind('drop', drop).bind('dragenter', dragEnter).bind('dragover', dragOver).bind('dragleave', dragLeave);

		$(document).bind('drop', docDrop).bind('dragenter', docEnter).bind('dragover', docOver).bind('dragleave', docLeave);

	};

	function drop(e) {

		opts.drop(e);

		files = e.dataTransfer.files;

		if (files === null || files === undefined) {

			opts.error(errors[0]);

			return false;

		}

		files_count = files.length;

		upload();

		e.preventDefault();

		return false;

	}

	function getBuilder(filename, filedata, boundary) {

		var dashdash = '--',

			crlf = '\r\n',

			builder = '';

		$.each(opts.data, function(i, val) {

	    	if (typeof val === 'function') val = val();

			builder += dashdash;

			builder += boundary;

			builder += crlf;

			builder += 'Content-Disposition: form-data; name="'+i+'"';

			builder += crlf;

			builder += crlf;

			builder += val;

			builder += crlf;

		});

		builder += dashdash;

		builder += boundary;

		builder += crlf;

		builder += 'Content-Disposition: form-data; name="'+opts.paramname+'"';

		builder += '; filename="' + filename + '"';

		builder += crlf;

		builder += 'Content-Type: application/octet-stream';

		builder += crlf;

		builder += crlf; 

		builder += filedata;

		builder += crlf;

		builder += dashdash;

		builder += boundary;

		builder += dashdash;

		builder += crlf;

		return builder;

	}

	function progress(e) {

		if (e.lengthComputable) {

			var percentage = Math.round((e.loaded * 100) / e.total);

			if (this.currentProgress != percentage) {

				this.currentProgress = percentage;

				opts.progressUpdated(this.index, this.file, this.currentProgress);

				var elapsed = new Date().getTime();

				var diffTime = elapsed - this.currentStart;

				if (diffTime >= opts.refresh) {

					var diffData = e.loaded - this.startData;

					var speed = diffData / diffTime; // KB per second

					opts.speedUpdated(this.index, this.file, speed);

					this.startData = e.loaded;

					this.currentStart = elapsed;

				}

			}

		}

	}

	function upload() {

		stop_loop = false;

		if (!files) {

			opts.error(errors[0]);

			return false;

		}

		var filesDone = 0,

			filesRejected = 0;

		if (files_count > opts.maxfiles) {

		    opts.error(errors[1]);

		    return false;

		}

		for (var i=0; i<files_count; i++) {

			if (stop_loop) return false;

			try {

				if (beforeEach(files[i]) != false) {

					if (i === files_count) return;

					var reader = new FileReader(),

						max_file_size = 1048576 * opts.maxfilesize;

					reader.index = i;

					if (files[i].size > max_file_size) {

						opts.error(errors[2], files[i], i);

						filesRejected++;

						continue;

					}

					reader.onloadend = send;

					reader.readAsBinaryString(files[i]);

				} else {

					filesRejected++;

				}

			} catch(err) {

				opts.error(errors[0]);

				return false;

			}

		}

		function send(e) {

			// Sometimes the index is not attached to the

			// event object. Find it by size. Hack for sure.

			if (e.target.index == undefined) {

				e.target.index = getIndexBySize(e.total);

			}

			var xhr = new XMLHttpRequest(),

				upload = xhr.upload,

				file = files[e.target.index],

				index = e.target.index,

				start_time = new Date().getTime(),

				boundary = '------multipartformboundary' + (new Date).getTime(),

				builder;

			newName = rename(file.name);

			if (typeof newName === "string") {

				builder = getBuilder(newName, e.target.result, boundary);

			} else {

				builder = getBuilder(file.name, e.target.result, boundary);

			}

			upload.index = index;

			upload.file = file;

			upload.downloadStartTime = start_time;

			upload.currentStart = start_time;

			upload.currentProgress = 0;

			upload.startData = 0;

			upload.addEventListener("progress", progress, false);

			xhr.open("POST", opts.url, true);

			xhr.setRequestHeader('content-type', 'multipart/form-data; boundary=' 

			    + boundary);

			xhr.sendAsBinary(builder);  

			opts.uploadStarted(index, file, files_count);  

			xhr.onload = function() { 

			    if (xhr.responseText) {

				var now = new Date().getTime(),

				    timeDiff = now - start_time,

				    result = opts.uploadFinished(index, file, jQuery.parseJSON(xhr.responseText), timeDiff);

					filesDone++;

					if (filesDone == files_count - filesRejected) {

						afterAll();

					}

			    if (result === false) stop_loop = true;

			    }

			};

		}

	}

	function getIndexBySize(size) {

		for (var i=0; i < files_count; i++) {

			if (files[i].size == size) {

				return i;

			}

		}

		return undefined;

	}

	function rename(name) {

		return opts.rename(name);

	}

	function beforeEach(file) {

		return opts.beforeEach(file);

	}

	function afterAll() {

		return opts.afterAll();

	}

	function dragEnter(e) {

		clearTimeout(doc_leave_timer);

		e.preventDefault();

		opts.dragEnter(e);

	}

	function dragOver(e) {

		clearTimeout(doc_leave_timer);

		e.preventDefault();

		opts.docOver(e);

		opts.dragOver(e);

	}

	function dragLeave(e) {

		clearTimeout(doc_leave_timer);

		opts.dragLeave(e);

		e.stopPropagation();

	}

	function docDrop(e) {

		e.preventDefault();

		opts.docLeave(e);

		return false;

	}

	function docEnter(e) {

		clearTimeout(doc_leave_timer);

		e.preventDefault();

		opts.docEnter(e);

		return false;

	}

	function docOver(e) {

		clearTimeout(doc_leave_timer);

		e.preventDefault();

		opts.docOver(e);

		return false;

	}

	function docLeave(e) {

		doc_leave_timer = setTimeout(function(){

			opts.docLeave(e);

		}, 200);

	}

	function empty(){}

	try {

		if (XMLHttpRequest.prototype.sendAsBinary) return;

		XMLHttpRequest.prototype.sendAsBinary = function(datastr) {

		    function byteValue(x) {

		        return x.charCodeAt(0) & 0xff;

		    }

		    var ords = Array.prototype.map.call(datastr, byteValue);

		    var ui8a = new Uint8Array(ords);

		    this.send(ui8a.buffer);

		}

	} catch(e) {}

})(jQuery);