/src/javascript/plupload.html5.js

/**

 * plupload.html5.js

 *

 * Copyright 2009, Moxiecode Systems AB

 * Released under GPL License.

 *

 * License: http://www.plupload.com/license

 * Contributing: http://www.plupload.com/contributing

 */



// JSLint defined globals

/*global plupload:false, File:false, window:false, atob:false, FormData:false, FileReader:false, ArrayBuffer:false, Uint8Array:false, BlobBuilder:false, unescape:false */



(function(window, document, plupload, undef) {

	var fakeSafariDragDrop;

	

	/* Introduce sendAsBinary for latest WebKits having support for BlobBuilder and typed arrays:

	credits: http://javascript0.org/wiki/Portable_sendAsBinary, 

	more info: http://code.google.com/p/chromium/issues/detail?id=35705 

	*/			

	if (window.Uint8Array && window.ArrayBuffer && !XMLHttpRequest.prototype.sendAsBinary) {

		XMLHttpRequest.prototype.sendAsBinary = function(datastr) {

			var ui8a = new Uint8Array(datastr.length);

			for (var i = 0; i < datastr.length; i++) {

				ui8a[i] = (datastr.charCodeAt(i) & 0xff);

			}

			this.send(ui8a.buffer);

		};

	}

	



	function readFileAsDataURL(file, callback) {

		var reader;



		// Use FileReader if it's available

		if ("FileReader" in window) {

			reader = new FileReader();

			reader.readAsDataURL(file);

			reader.onload = function() {

				callback(reader.result);

			};

		} else {

			return callback(file.getAsDataURL());

		}

	}



	function readFileAsBinary(file, callback) {

		var reader;



		// Use FileReader if it's available

		if ("FileReader" in window) {

			reader = new FileReader();

			reader.readAsBinaryString(file);

			reader.onload = function() {

				callback(reader.result);

			};

		} else {

			return callback(file.getAsBinary());

		}

	}



	function scaleImage(image_file, resize, mime, callback) {

		var canvas, context, img, scale;



		readFileAsDataURL(image_file, function(data) {

			// Setup canvas and context

			canvas = document.createElement("canvas");

			canvas.style.display = 'none';

			document.body.appendChild(canvas);

			context = canvas.getContext('2d');



			// Load image

			img = new Image();

			img.onerror = img.onabort = function() {

				// Failed to load, the image may be invalid

				callback({success : false});

			};

			img.onload = function() {

				var width, height, percentage, jpegHeaders, exifParser;

				

				if (!resize['width']) {

					resize['width'] = img.width;

				}

				

				if (!resize['height']) {

					resize['height'] = img.height;	

				}

				

				scale = Math.min(resize.width / img.width, resize.height / img.height);



				if (scale < 1 || (scale === 1 && mime === 'image/jpeg')) {

					width = Math.round(img.width * scale);

					height = Math.round(img.height * scale);



					// Scale image and canvas

					canvas.width = width;

					canvas.height = height;

					context.drawImage(img, 0, 0, width, height);

					

					// Preserve JPEG headers

					if (mime === 'image/jpeg') {

						jpegHeaders = new JPEG_Headers(atob(data.substring(data.indexOf('base64,') + 7)));

						if (jpegHeaders['headers'] && jpegHeaders['headers'].length) {

							exifParser = new ExifParser();			

											

							if (exifParser.init(jpegHeaders.get('exif')[0])) {

								// Set new width and height

								exifParser.setExif('PixelXDimension', width);

								exifParser.setExif('PixelYDimension', height);

															

								// Update EXIF header

								jpegHeaders.set('exif', exifParser.getBinary());

							}

						}

						

						if (resize['quality']) {							

							// Try quality property first

							try {

								data = canvas.toDataURL(mime, resize['quality'] / 100);	

							} catch (e) {

								data = canvas.toDataURL(mime);	

							}

						}

					} else {

						data = canvas.toDataURL(mime);

					}



					// Remove data prefix information and grab the base64 encoded data and decode it

					data = data.substring(data.indexOf('base64,') + 7);

					data = atob(data);



					// Restore JPEG headers if applicable

					if (jpegHeaders && jpegHeaders['headers'] && jpegHeaders['headers'].length) {

						data = jpegHeaders.restore(data);

						jpegHeaders.purge(); // free memory

					}



					// Remove canvas and execute callback with decoded image data

					canvas.parentNode.removeChild(canvas);

					callback({success : true, data : data});

				} else {

					// Image does not need to be resized

					callback({success : false});

				}

			};



			img.src = data;

		});

	}



	/**

	 * HMTL5 implementation. This runtime supports these features: dragdrop, jpgresize, pngresize.

	 *

	 * @static

	 * @class plupload.runtimes.Html5

	 * @extends plupload.Runtime

	 */

	plupload.runtimes.Html5 = plupload.addRuntime("html5", {

		/**

		 * Returns a list of supported features for the runtime.

		 *

		 * @return {Object} Name/value object with supported features.

		 */

		getFeatures : function() {

			var xhr, hasXhrSupport, hasProgress, dataAccessSupport, sliceSupport, win = window;



			hasXhrSupport = hasProgress = dataAccessSupport = sliceSupport = false;

			

			if (win.XMLHttpRequest) {

				xhr = new XMLHttpRequest();

				hasProgress = !!xhr.upload;

				hasXhrSupport = !!(xhr.sendAsBinary || xhr.upload);

			}



			// Check for support for various features

			if (hasXhrSupport) {

				// Set dataAccessSupport only for Gecko since BlobBuilder and XHR doesn't handle binary data correctly				

				dataAccessSupport = !!(File && (File.prototype.getAsDataURL || win.FileReader) && xhr.sendAsBinary);

				sliceSupport = !!(File && File.prototype.slice);

			}



			// Sniff for Safari and fake drag/drop

			fakeSafariDragDrop = navigator.userAgent.indexOf('Safari') > 0 && navigator.vendor.indexOf('Apple') !== -1;



			return {

				// Detect drag/drop file support by sniffing, will try to find a better way

				html5: hasXhrSupport, // This is a special one that we check inside the init call

				dragdrop: win.mozInnerScreenX !== undef || sliceSupport || fakeSafariDragDrop,

				jpgresize: dataAccessSupport,

				pngresize: dataAccessSupport,

				multipart: dataAccessSupport || !!win.FileReader || !!win.FormData,

				progress: hasProgress,

				chunks: sliceSupport || dataAccessSupport,

				

				/* WebKit let you trigger file dialog programmatically while FF and Opera - do not, so we

				sniff for it here... probably not that good idea, but impossibillity of controlling cursor style  

				on top of add files button obviously feels even worse */

				canOpenDialog: navigator.userAgent.indexOf('WebKit') !== -1

			};

		},



		/**

		 * Initializes the upload runtime.

		 *

		 * @method init

		 * @param {plupload.Uploader} uploader Uploader instance that needs to be initialized.

		 * @param {function} callback Callback to execute when the runtime initializes or fails to initialize. If it succeeds an object with a parameter name success will be set to true.

		 */

		init : function(uploader, callback) {

			var html5files = {}, features;



			function addSelectedFiles(native_files) {

				var file, i, files = [], id, fileNames = {};



				// Add the selected files to the file queue

				for (i = 0; i < native_files.length; i++) {

					file = native_files[i];

					

					// Safari on Windows will add first file from dragged set multiple times

					// @see: https://bugs.webkit.org/show_bug.cgi?id=37957

					if (fileNames[file.name]) {

						continue;

					}

					fileNames[file.name] = true;



					// Store away gears blob internally

					id = plupload.guid();

					html5files[id] = file;



					// Expose id, name and size

					files.push(new plupload.File(id, file.fileName, file.fileSize || file.size)); // File.fileSize depricated

				}



				// Trigger FilesAdded event if we added any

				if (files.length) {

					uploader.trigger("FilesAdded", files);

				}

			}



			// No HTML5 upload support

			features = this.getFeatures();

			if (!features.html5) {

				callback({success : false});

				return;

			}



			uploader.bind("Init", function(up) {

				var inputContainer, browseButton, mimes = [], i, y, filters = up.settings.filters, ext, type, container = document.body, inputFile;



				// Create input container and insert it at an absolute position within the browse button

				inputContainer = document.createElement('div');

				inputContainer.id = up.id + '_html5_container';



				plupload.extend(inputContainer.style, {

					position : 'absolute',

					background : uploader.settings.shim_bgcolor || 'transparent',

					width : '100px',

					height : '100px',

					overflow : 'hidden',

					zIndex : 99999,

					opacity : uploader.settings.shim_bgcolor ? '' : 0 // Force transparent if bgcolor is undefined

				});



				inputContainer.className = 'plupload html5';



				if (uploader.settings.container) {

					container = document.getElementById(uploader.settings.container);

					if (plupload.getStyle(container, 'position') === 'static') {

						container.style.position = 'relative';

					}

				}



				container.appendChild(inputContainer);

				

				// Convert extensions to mime types list

				no_type_restriction:

				for (i = 0; i < filters.length; i++) {

					ext = filters[i].extensions.split(/,/);



					for (y = 0; y < ext.length; y++) {

						

						// If there's an asterisk in the list, then accept attribute is not required

						if (ext[y] === '*') {

							mimes = [];

							break no_type_restriction;

						}

						

						type = plupload.mimeTypes[ext[y]];



						if (type) {

							mimes.push(type);

						}

					}

				}





				// Insert the input inside the input container

				inputContainer.innerHTML = '<input id="' + uploader.id + '_html5" ' +

											'style="width:100%;height:100%;font-size:99px" type="file" accept="' + 

											mimes.join(',') + '" ' +

											(uploader.settings.multi_selection ? 'multiple="multiple"' : '') + ' />';

				

				inputFile = document.getElementById(uploader.id + '_html5');

				inputFile.onchange = function() {

					// Add the selected files from file input

					addSelectedFiles(this.files);



					// Clearing the value enables the user to select the same file again if they want to

					this.value = '';

				};

				

				/* Since we have to place input[type=file] on top of the browse_button for some browsers (FF, Opera),

				browse_button loses interactivity, here we try to neutralize this issue highlighting browse_button

				with a special class

				TODO: needs to be revised as things will change */

				browseButton = document.getElementById(up.settings.browse_button);

				if (browseButton) {				

					var hoverClass = up.settings.browse_button_hover,

						activeClass = up.settings.browse_button_active,

						topElement = up.features.canOpenDialog ? browseButton : inputContainer;

					

					if (hoverClass) {

						plupload.addEvent(topElement, 'mouseover', function() {

							plupload.addClass(browseButton, hoverClass);	

						}, up.id);

						plupload.addEvent(topElement, 'mouseout', function() {

							plupload.removeClass(browseButton, hoverClass);	

						}, up.id);

					}

					

					if (activeClass) {

						plupload.addEvent(topElement, 'mousedown', function() {

							plupload.addClass(browseButton, activeClass);	

						}, up.id);

						plupload.addEvent(document.body, 'mouseup', function() {

							plupload.removeClass(browseButton, activeClass);	

						}, up.id);

					}



					// Route click event to the input[type=file] element for supporting browsers

					if (up.features.canOpenDialog) {

						plupload.addEvent(browseButton, 'click', function(e) {

							document.getElementById(up.id + '_html5').click();

							e.preventDefault();

						}, up.id); 

					}

				}

			});



			// Add drop handler

			uploader.bind("PostInit", function() {

				var dropElm = document.getElementById(uploader.settings.drop_element);



				if (dropElm) {

					// Lets fake drag/drop on Safari by moving a input type file in front of the mouse pointer when we drag into the drop zone

					// TODO: Remove this logic once Safari has official drag/drop support

					if (fakeSafariDragDrop) {

						plupload.addEvent(dropElm, 'dragenter', function(e) {

							var dropInputElm, dropPos, dropSize;



							// Get or create drop zone

							dropInputElm = document.getElementById(uploader.id + "_drop");

							if (!dropInputElm) {

								dropInputElm = document.createElement("input");

								dropInputElm.setAttribute('type', "file");

								dropInputElm.setAttribute('id', uploader.id + "_drop");

								dropInputElm.setAttribute('multiple', 'multiple');



								plupload.addEvent(dropInputElm, 'change', function() {

									// Add the selected files from file input

									addSelectedFiles(this.files);

									

									// Remove input element

									plupload.removeEvent(dropInputElm, 'change', uploader.id);

									dropInputElm.parentNode.removeChild(dropInputElm);									

								}, uploader.id);

								

								dropElm.appendChild(dropInputElm);

							}



							dropPos = plupload.getPos(dropElm, document.getElementById(uploader.settings.container));

							dropSize = plupload.getSize(dropElm);

							

							if (plupload.getStyle(dropElm, 'position') === 'static') {

								plupload.extend(dropElm.style, {

									position : 'relative'

								});

							}

              

							plupload.extend(dropInputElm.style, {

								position : 'absolute',

								display : 'block',

								top : 0,

								left : 0,

								width : dropSize.w + 'px',

								height : dropSize.h + 'px',

								opacity : 0

							});							

						}, uploader.id);



						return;

					}



					// Block browser default drag over

					plupload.addEvent(dropElm, 'dragover', function(e) {

						e.preventDefault();

					}, uploader.id);



					// Attach drop handler and grab files

					plupload.addEvent(dropElm, 'drop', function(e) {

						var dataTransfer = e.dataTransfer;



						// Add dropped files

						if (dataTransfer && dataTransfer.files) {

							addSelectedFiles(dataTransfer.files);

						}



						e.preventDefault();

					}, uploader.id);

				}

			});



			uploader.bind("Refresh", function(up) {

				var browseButton, browsePos, browseSize, inputContainer, pzIndex;

					

				browseButton = document.getElementById(uploader.settings.browse_button);

				if (browseButton) {

					browsePos = plupload.getPos(browseButton, document.getElementById(up.settings.container));

					browseSize = plupload.getSize(browseButton);

					inputContainer = document.getElementById(uploader.id + '_html5_container');

	

					plupload.extend(inputContainer.style, {

						top : browsePos.y + 'px',

						left : browsePos.x + 'px',

						width : browseSize.w + 'px',

						height : browseSize.h + 'px'

					});

					

					// for WebKit place input element underneath the browse button and route onclick event 

					// TODO: revise when browser support for this feature will change

					if (uploader.features.canOpenDialog) {

						pzIndex = parseInt(browseButton.parentNode.style.zIndex, 10);

	

						if (isNaN(pzIndex)) {

							pzIndex = 0;

						}

							

						plupload.extend(browseButton.style, {

							zIndex : pzIndex

						});

            

						if (plupload.getStyle(browseButton, 'position') === 'static') {

							plupload.extend(browseButton.style, {

								position : 'relative'

							});

						}

											

						plupload.extend(inputContainer.style, {

							zIndex : pzIndex - 1

						});

					}

				}

			});



			uploader.bind("UploadFile", function(up, file) {

				var settings = up.settings, nativeFile, resize;



				function sendBinaryBlob(blob) {

					var chunk = 0, loaded = 0;



					function uploadNextChunk() {

						var chunkBlob = blob, xhr, upload, chunks, args, multipartDeltaSize = 0,

							boundary = '----pluploadboundary' + plupload.guid(), chunkSize, curChunkSize, formData,

							dashdash = '--', crlf = '\r\n', multipartBlob = '', mimeType, url = up.settings.url;



						// File upload finished

						if (file.status == plupload.DONE || file.status == plupload.FAILED || up.state == plupload.STOPPED) {

							return;

						}



						// Standard arguments

						args = {name : file.target_name || file.name};



						// Only add chunking args if needed

						if (settings.chunk_size && features.chunks) {

							chunkSize = settings.chunk_size;

							chunks = Math.ceil(file.size / chunkSize);

							curChunkSize = Math.min(chunkSize, file.size - (chunk * chunkSize));



							// Blob is string so we need to fake chunking, this is not

							// ideal since the whole file is loaded into memory

							if (typeof(blob) == 'string') {

								chunkBlob = blob.substring(chunk * chunkSize, chunk * chunkSize + curChunkSize);

							} else {

								// Slice the chunk

								chunkBlob = blob.slice(chunk * chunkSize, curChunkSize);

							}



							// Setup query string arguments

							args.chunk = chunk;

							args.chunks = chunks;

						} else {

							curChunkSize = file.size;

						}



						// Setup XHR object

						xhr = new XMLHttpRequest();

						upload = xhr.upload;



						// Do we have upload progress support

						if (upload) {

							upload.onprogress = function(e) {

								file.loaded = Math.min(file.size, loaded + e.loaded - multipartDeltaSize); // Loaded can be larger than file size due to multipart encoding

								up.trigger('UploadProgress', file);

							};

						}



						// Add name, chunk and chunks to query string on direct streaming

						if (!up.settings.multipart || !features.multipart) {

							url = plupload.buildUrl(up.settings.url, args);

						} else {

							args.name = file.target_name || file.name;

						}



						xhr.open("post", url, true);



						xhr.onreadystatechange = function() {

							var httpStatus, chunkArgs;



							if (xhr.readyState == 4) {

								// Getting the HTTP status might fail on some Gecko versions

								try {

									httpStatus = xhr.status;

								} catch (ex) {

									httpStatus = 0;

								}



								// Is error status

								if (httpStatus >= 400) {

									up.trigger('Error', {

										code : plupload.HTTP_ERROR,

										message : plupload.translate('HTTP Error.'),

										file : file,

										status : httpStatus

									});

								} else {

									// Handle chunk response

									if (chunks) {

										chunkArgs = {

											chunk : chunk,

											chunks : chunks,

											response : xhr.responseText,

											status : httpStatus

										};



										up.trigger('ChunkUploaded', file, chunkArgs);

										loaded += curChunkSize;



										// Stop upload

										if (chunkArgs.cancelled) {

											file.status = plupload.FAILED;

											return;

										}



										file.loaded = Math.min(file.size, (chunk + 1) * chunkSize);

									} else {

										file.loaded = file.size;

									}



									up.trigger('UploadProgress', file);



									// Check if file is uploaded

									if (!chunks || ++chunk >= chunks) {

										file.status = plupload.DONE;

										up.trigger('FileUploaded', file, {

											response : xhr.responseText,

											status : httpStatus

										});



										nativeFile = blob = html5files[file.id] = null; // Free memory

									} else {

										// Still chunks left

										uploadNextChunk();

									}

								}



								xhr = chunkBlob = formData = multipartBlob = null; // Free memory

							}

						};



						// Set custom headers

						plupload.each(up.settings.headers, function(value, name) {

							xhr.setRequestHeader(name, value);

						});



						// Build multipart request

						if (up.settings.multipart && features.multipart) {

							// Has FormData support like Chrome 6+, Safari 5+, Firefox 4

							if (!xhr.sendAsBinary) {

								formData = new FormData();



								// Add multipart params

								plupload.each(plupload.extend(args, up.settings.multipart_params), function(value, name) {

									formData.append(name, value);

								});



								// Add file and send it

								formData.append(up.settings.file_data_name, chunkBlob);

								xhr.send(formData);



								return;

							}



							// Gecko multipart request

							xhr.setRequestHeader('Content-Type', 'multipart/form-data; boundary=' + boundary);



							// Append multipart parameters

							plupload.each(plupload.extend(args, up.settings.multipart_params), function(value, name) {

								multipartBlob += dashdash + boundary + crlf +

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



								multipartBlob += unescape(encodeURIComponent(value)) + crlf;

							});



							mimeType = plupload.mimeTypes[file.name.replace(/^.+\.([^.]+)/, '$1').toLowerCase()] || 'application/octet-stream';



							// Build RFC2388 blob

							multipartBlob += dashdash + boundary + crlf +

								'Content-Disposition: form-data; name="' + up.settings.file_data_name + '"; filename="' + unescape(encodeURIComponent(file.name)) + '"' + crlf +

								'Content-Type: ' + mimeType + crlf + crlf +

								chunkBlob + crlf +

								dashdash + boundary + dashdash + crlf;



							multipartDeltaSize = multipartBlob.length - chunkBlob.length;

							chunkBlob = multipartBlob;

						} else {

							// Binary stream header

							xhr.setRequestHeader('Content-Type', 'application/octet-stream');

						}



						if (xhr.sendAsBinary) {

							xhr.sendAsBinary(chunkBlob); // Gecko

						} else {

							xhr.send(chunkBlob); // WebKit

						}

					}



					// Start uploading chunks

					uploadNextChunk();

				}



				nativeFile = html5files[file.id];

				resize = up.settings.resize;



				if (features.jpgresize) {

					// Resize image if it's a supported format and resize is enabled

					if (resize && /\.(png|jpg|jpeg)$/i.test(file.name)) {

						scaleImage(nativeFile, resize, /\.png$/i.test(file.name) ? 'image/png' : 'image/jpeg', function(res) {

							// If it was scaled send the scaled image if it failed then

							// send the raw image and let the server do the scaling

							if (res.success) {

								file.size = res.data.length;

								sendBinaryBlob(res.data);

							} else {

								readFileAsBinary(nativeFile, sendBinaryBlob);

							}

						});

					} else {

						readFileAsBinary(nativeFile, sendBinaryBlob);

					}

				} else {

					sendBinaryBlob(nativeFile); // this works on older WebKits, but fails on fresh ones

				}

			});

			

			

			uploader.bind('Destroy', function(up) {

				var name, element, container = document.body,

					elements = {

						inputContainer: up.id + '_html5_container',

						inputFile: up.id + '_html5',

						browseButton: up.settings.browse_button,

						dropElm: up.settings.drop_element

					};



				// Unbind event handlers

				for (name in elements) {

					element = document.getElementById(elements[name]);

					if (element) {

						plupload.removeAllEvents(element, up.id);

					}

				}

				plupload.removeAllEvents(document.body, up.id);

				

				if (up.settings.container) {

					container = document.getElementById(up.settings.container);

				}

				

				// Remove mark-up

				container.removeChild(document.getElementById(elements.inputContainer));

			});



			callback({success : true});

		}

	});

	

	function BinaryReader() {

		var II = false, bin;



		// Private functions

		function read(idx, size) {

			var mv = II ? 0 : -8 * (size - 1), sum = 0, i;



			for (i = 0; i < size; i++) {

				sum |= (bin.charCodeAt(idx + i) << Math.abs(mv + i*8));

			}



			return sum;

		}



		function putstr(segment, idx, length) {

			var length = arguments.length === 3 ? length : bin.length - idx - 1;

			

			bin = bin.substr(0, idx) + segment + bin.substr(length + idx);

		}



		function write(idx, num, size) {

			var str = '', mv = II ? 0 : -8 * (size - 1), i;



			for (i = 0; i < size; i++) {

				str += String.fromCharCode((num >> Math.abs(mv + i*8)) & 255);

			}



			putstr(str, idx, size);

		}



		// Public functions

		return {

			II: function(order) {

				if (order === undef) {

					return II;

				} else {

					II = order;

				}

			},



			init: function(binData) {

				II = false;

				bin = binData;

			},



			SEGMENT: function(idx, length, segment) {				

				switch (arguments.length) {

					case 1: 

						return bin.substr(idx, bin.length - idx - 1);

					case 2: 

						return bin.substr(idx, length);

					case 3: 

						putstr(segment, idx, length);

						break;

					default: return bin;	

				}

			},



			BYTE: function(idx) {

				return read(idx, 1);

			},



			SHORT: function(idx) {

				return read(idx, 2);

			},



			LONG: function(idx, num) {

				if (num === undef) {

					return read(idx, 4);

				} else {

					write(idx, num, 4);

				}

			},



			SLONG: function(idx) { // 2's complement notation

				var num = read(idx, 4);



				return (num > 2147483647 ? num - 4294967296 : num);

			},



			STRING: function(idx, size) {

				var str = '';



				for (size += idx; idx < size; idx++) {

					str += String.fromCharCode(read(idx, 1));

				}



				return str;

			}

		};

	}

	

	function JPEG_Headers(data) {

		

		var markers = {

				0xFFE1: {

					app: 'EXIF',

					name: 'APP1',

					signature: "Exif\0" 

				},

				0xFFE2: {

					app: 'ICC',

					name: 'APP2',

					signature: "ICC_PROFILE\0" 

				},

				0xFFED: {

					app: 'IPTC',

					name: 'APP13',

					signature: "Photoshop 3.0\0" 

				}

			},

			headers = [], read, idx, marker = undef, length = 0, limit;

			

		

		read = new BinaryReader();

		read.init(data);

				

		// Check if data is jpeg

		if (read.SHORT(0) !== 0xFFD8) {

			return;

		}

		

		idx = 2;

		limit = Math.min(1048576, data.length);	

			

		while (idx <= limit) {

			marker = read.SHORT(idx);

			

			// omit RST (restart) markers

			if (marker >= 0xFFD0 && marker <= 0xFFD7) {

				idx += 2;

				continue;

			}

			

			// no headers allowed after SOS marker

			if (marker === 0xFFDA || marker === 0xFFD9) {

				break;	

			}	

			

			length = read.SHORT(idx + 2) + 2;	

			

			if (markers[marker] && 

				read.STRING(idx + 4, markers[marker].signature.length) === markers[marker].signature) {

				headers.push({ 

					hex: marker,

					app: markers[marker].app.toUpperCase(),

					name: markers[marker].name.toUpperCase(),

					start: idx,

					length: length,

					segment: read.SEGMENT(idx, length)

				});

			}

			idx += length;			

		}

					

		read.init(null); // free memory

						

		return {

			

			headers: headers,

			

			restore: function(data) {

				read.init(data);

				

				// Check if data is jpeg

				var jpegHeaders = new JPEG_Headers(data);

				

				if (!jpegHeaders['headers']) {

					return false;

				}	

				

				// Delete any existing headers that need to be replaced

				for (var i = jpegHeaders['headers'].length; i > 0; i--) {

					var hdr = jpegHeaders['headers'][i - 1];

					read.SEGMENT(hdr.start, hdr.length, '')

				}

				jpegHeaders.purge();

				

				idx = read.SHORT(2) == 0xFFE0 ? 4 + read.SHORT(4) : 2;

								

				for (var i = 0, max = headers.length; i < max; i++) {

					read.SEGMENT(idx, 0, headers[i].segment);						

					idx += headers[i].length;

				}

				

				return read.SEGMENT();

			},

			

			get: function(app) {

				var array = [];

								

				for (var i = 0, max = headers.length; i < max; i++) {

					if (headers[i].app === app.toUpperCase()) {

						array.push(headers[i].segment);

					}

				}

				return array;

			},

			

			set: function(app, segment) {

				var array = [];

				

				if (typeof(segment) === 'string') {

					array.push(segment);	

				} else {

					array = segment;	

				}

				

				for (var i = ii = 0, max = headers.length; i < max; i++) {

					if (headers[i].app === app.toUpperCase()) {

						headers[i].segment = array[ii];

						headers[i].length = array[ii].length;

						ii++;

					}

					if (ii >= array.length) break;

				}

			},

			

			purge: function() {

				headers = [];

				read.init(null);

			}

		};		

	}

	

	

	function ExifParser() {

		// Private ExifParser fields

		var data, tags, offsets = {}, tagDescs;



		data = new BinaryReader();



		tags = {

			tiff : {

				/*

				The image orientation viewed in terms of rows and columns.

	

				1 - The 0th row is at the visual top of the image, and the 0th column is the visual left-hand side.

				2 - The 0th row is at the visual top of the image, and the 0th column is the visual left-hand side.

				3 - The 0th row is at the visual top of the image, and the 0th column is the visual right-hand side.

				4 - The 0th row is at the visual bottom of the image, and the 0th column is the visual right-hand side.

				5 - The 0th row is at the visual bottom of the image, and the 0th column is the visual left-hand side.

				6 - The 0th row is the visual left-hand side of the image, and the 0th column is the visual top.

				7 - The 0th row is the visual right-hand side of the image, and the 0th column is the visual top.

				8 - The 0th row is the visual right-hand side of the image, and the 0th column is the visual bottom.

				9 - The 0th row is the visual left-hand side of the image, and the 0th column is the visual bottom.

				*/

				0x0112: 'Orientation',

				0x8769: 'ExifIFDPointer',

				0x8825:	'GPSInfoIFDPointer'

			},

			exif : {

				0x9000: 'ExifVersion',

				0xA001: 'ColorSpace',

				0xA002: 'PixelXDimension',

				0xA003: 'PixelYDimension',

				0x9003: 'DateTimeOriginal',

				0x829A: 'ExposureTime',

				0x829D: 'FNumber',

				0x8827: 'ISOSpeedRatings',

				0x9201: 'ShutterSpeedValue',

				0x9202: 'ApertureValue'	,

				0x9207: 'MeteringMode',

				0x9208: 'LightSource',

				0x9209: 'Flash',

				0xA402: 'ExposureMode',

				0xA403: 'WhiteBalance',

				0xA406: 'SceneCaptureType',

				0xA404: 'DigitalZoomRatio',

				0xA408: 'Contrast',

				0xA409: 'Saturation',

				0xA40A: 'Sharpness'

			},

			gps : {

				0x0000: 'GPSVersionID',

				0x0001: 'GPSLatitudeRef',

				0x0002: 'GPSLatitude',

				0x0003: 'GPSLongitudeRef',

				0x0004: 'GPSLongitude'

			}

		};



		tagDescs = {

			'ColorSpace': {

				1: 'sRGB',

				0: 'Uncalibrated'

			},



			'MeteringMode': {

				0: 'Unknown',

				1: 'Average',

				2: 'CenterWeightedAverage',

				3: 'Spot',

				4: 'MultiSpot',

				5: 'Pattern',

				6: 'Partial',

				255: 'Other'

			},



			'LightSource': {

				1: 'Daylight',

				2: 'Fliorescent',

				3: 'Tungsten',

				4: 'Flash',

				9: 'Fine weather',

				10: 'Cloudy weather',

				11: 'Shade',

				12: 'Daylight fluorescent (D 5700 - 7100K)',

				13: 'Day white fluorescent (N 4600 -5400K)',

				14: 'Cool white fluorescent (W 3900 - 4500K)',

				15: 'White fluorescent (WW 3200 - 3700K)',

				17: 'Standard light A',

				18: 'Standard light B',

				19: 'Standard light C',

				20: 'D55',

				21: 'D65',

				22: 'D75',

				23: 'D50',

				24: 'ISO studio tungsten',

				255: 'Other'

			},



			'Flash': {

				0x0000: 'Flash did not fire.',

				0x0001: 'Flash fired.',

				0x0005: 'Strobe return light not detected.',

				0x0007: 'Strobe return light detected.',

				0x0009: 'Flash fired, compulsory flash mode',

				0x000D: 'Flash fired, compulsory flash mode, return light not detected',

				0x000F: 'Flash fired, compulsory flash mode, return light detected',

				0x0010: 'Flash did not fire, compulsory flash mode',

				0x0018: 'Flash did not fire, auto mode',

				0x0019: 'Flash fired, auto mode',

				0x001D: 'Flash fired, auto mode, return light not detected',

				0x001F: 'Flash fired, auto mode, return light detected',

				0x0020: 'No flash function',

				0x0041: 'Flash fired, red-eye reduction mode',

				0x0045: 'Flash fired, red-eye reduction mode, return light not detected',

				0x0047: 'Flash fired, red-eye reduction mode, return light detected',

				0x0049: 'Flash fired, compulsory flash mode, red-eye reduction mode',

				0x004D: 'Flash fired, compulsory flash mode, red-eye reduction mode, return light not detected',

				0x004F: 'Flash fired, compulsory flash mode, red-eye reduction mode, return light detected',

				0x0059: 'Flash fired, auto mode, red-eye reduction mode',

				0x005D: 'Flash fired, auto mode, return light not detected, red-eye reduction mode',

				0x005F: 'Flash fired, auto mode, return light detected, red-eye reduction mode'

			},



			'ExposureMode': {

				0: 'Auto exposure',

				1: 'Manual exposure',

				2: 'Auto bracket'

			},



			'WhiteBalance': {

				0: 'Auto white balance',

				1: 'Manual white balance'

			},



			'SceneCaptureType': {

				0: 'Standard',

				1: 'Landscape',

				2: 'Portrait',

				3: 'Night scene'

			},



			'Contrast': {

				0: 'Normal',

				1: 'Soft',

				2: 'Hard'

			},



			'Saturation': {

				0: 'Normal',

				1: 'Low saturation',

				2: 'High saturation'

			},



			'Sharpness': {

				0: 'Normal',

				1: 'Soft',

				2: 'Hard'

			},



			// GPS related

			'GPSLatitudeRef': {

				N: 'North latitude',

				S: 'South latitude'

			},



			'GPSLongitudeRef': {

				E: 'East longitude',

				W: 'West longitude'

			}

		};



		function extractTags(IFD_offset, tags2extract) {

			var length = data.SHORT(IFD_offset), i, ii,

				tag, type, count, tagOffset, offset, value, values = [], hash = {};



			for (i = 0; i < length; i++) {

				// Set binary reader pointer to beginning of the next tag

				offset = tagOffset = IFD_offset + 12 * i + 2;



				tag = tags2extract[data.SHORT(offset)];



				if (tag === undef) {

					continue; // Not the tag we requested

				}



				type = data.SHORT(offset+=2);

				count = data.LONG(offset+=2);



				offset += 4;

				values = [];



				switch (type) {

					case 1: // BYTE

					case 7: // UNDEFINED

						if (count > 4) {

							offset = data.LONG(offset) + offsets.tiffHeader;

						}



						for (ii = 0; ii < count; ii++) {

							values[ii] = data.BYTE(offset + ii);

						}



						break;



					case 2: // STRING

						if (count > 4) {

							offset = data.LONG(offset) + offsets.tiffHeader;

						}



						hash[tag] = data.STRING(offset, count - 1);



						continue;



					case 3: // SHORT

						if (count > 2) {

							offset = data.LONG(offset) + offsets.tiffHeader;

						}



						for (ii = 0; ii < count; ii++) {

							values[ii] = data.SHORT(offset + ii*2);

						}



						break;



					case 4: // LONG

						if (count > 1) {

							offset = data.LONG(offset) + offsets.tiffHeader;

						}



						for (ii = 0; ii < count; ii++) {

							values[ii] = data.LONG(offset + ii*4);

						}



						break;



					case 5: // RATIONAL

						offset = data.LONG(offset) + offsets.tiffHeader;



						for (ii = 0; ii < count; ii++) {

							values[ii] = data.LONG(offset + ii*4) / data.LONG(offset + ii*4 + 4);

						}



						break;



					case 9: // SLONG

						offset = data.LONG(offset) + offsets.tiffHeader;



						for (ii = 0; ii < count; ii++) {

							values[ii] = data.SLONG(offset + ii*4);

						}



						break;



					case 10: // SRATIONAL

						offset = data.LONG(offset) + offsets.tiffHeader;



						for (ii = 0; ii < count; ii++) {

							values[ii] = data.SLONG(offset + ii*4) / data.SLONG(offset + ii*4 + 4);

						}



						break;



					default:

						continue;

				}



				value = (count == 1 ? values[0] : values);



				if (tagDescs.hasOwnProperty(tag) && typeof value != 'object') {

					hash[tag] = tagDescs[tag][value];

				} else {

					hash[tag] = value;

				}

			}



			return hash;

		}



		function getIFDOffsets() {

			var Tiff = undef, idx = offsets.tiffHeader;



			// Set read order of multi-byte data

			data.II(data.SHORT(idx) == 0x4949);



			// Check if always present bytes are indeed present

			if (data.SHORT(idx+=2) !== 0x002A) {

				return false;

			}

		

			offsets['IFD0'] = offsets.tiffHeader + data.LONG(idx += 2);

			Tiff = extractTags(offsets['IFD0'], tags.tiff);



			offsets['exifIFD'] = ('ExifIFDPointer' in Tiff ? offsets.tiffHeader + Tiff.ExifIFDPointer : undef);

			offsets['gpsIFD'] = ('GPSInfoIFDPointer' in Tiff ? offsets.tiffHeader + Tiff.GPSInfoIFDPointer : undef);



			return true;

		}

		

		// At the moment only setting of simple (LONG) values, that do not require offset recalculation, is supported

		function setTag(ifd, tag, value) {

			var offset, length, tagOffset, valueOffset = 0;

			

			// If tag name passed translate into hex key

			if (typeof(tag) === 'string') {

				var tmpTags = tags[ifd.toLowerCase()];

				for (hex in tmpTags) {

					if (tmpTags[hex] === tag) {

						tag = hex;

						break;	

					}

				}

			}

			offset = offsets[ifd.toLowerCase() + 'IFD'];

			length = data.SHORT(offset);

						

			for (i = 0; i < length; i++) {

				tagOffset = offset + 12 * i + 2;



				if (data.SHORT(tagOffset) == tag) {

					valueOffset = tagOffset + 8;

					break;

				}

			}

			

			if (!valueOffset) return false;



			

			data.LONG(valueOffset, value);

			return true;

		}

		



		// Public functions

		return {

			init: function(segment) {

				// Reset internal data

				offsets = {

					tiffHeader: 10

				};

				

				if (segment === undef || !segment.length) {

					return false;

				}



				data.init(segment);



				// Check if that's APP1 and that it has EXIF

				if (data.SHORT(0) === 0xFFE1 && data.STRING(4, 5).toUpperCase() === "EXIF\0") {

					return getIFDOffsets();

				}

				return false;

			},





			EXIF: function() {

				var Exif;

				

				// Populate EXIF hash

				Exif = extractTags(offsets.exifIFD, tags.exif);



				// Fix formatting of some tags

				Exif.ExifVersion = String.fromCharCode(

					Exif.ExifVersion[0],

					Exif.ExifVersion[1],

					Exif.ExifVersion[2],

					Exif.ExifVersion[3]

				);



				return Exif;

			},



			GPS: function() {

				var GPS;

				

				GPS = extractTags(offsets.gpsIFD, tags.gps);

				GPS.GPSVersionID = GPS.GPSVersionID.join('.');



				return GPS;

			},

			

			setExif: function(tag, value) {

				// Right now only setting of width/height is possible

				if (tag !== 'PixelXDimension' && tag !== 'PixelYDimension') return false;

				

				return setTag('exif', tag, value);

			},





			getBinary: function() {

				return data.SEGMENT();

			}

		};

	};

})(window, document, plupload);