angular-file-md5.js

(function (root, factory) {
	if (typeof define === 'function' && define.amd) {
		// AMD. Register as an anonymous module.
		define(['angular', 'spark-md5'], factory);
	} else if (typeof module === 'object' && module.exports) {
		// Node. Does not work with strict CommonJS, but
		// only CommonJS-like environments that support module.exports,
		// like Node.
		module.exports = factory(require('angular'), require('spark-md5'));
	} else {
		// Browser globals (root is window)
		return factory(root.angular, root.SparkMD5);
	}
}(this, function (angular, sparkMd5) {
	'use strict';
	var moduleName = 'ljungmann.fileMd5';

	angular.module(moduleName, [])
	.provider('fileMd5Service', [function() {

		var settings = {
			chunkSize: 2097152 // 2 MB
		};

		this.configure = function(additionalSettings) {
			angular.extend(settings, additionalSettings);

			return this;
		};

		this.$get = ['$q', function($q) {

			return {
				md5: function(file) {
					var slicer = File.prototype.slice || File.prototype.mozSlice || File.prototype.webkitSlice;
					var currentChunk = 0;
					var chunks = Math.ceil(file.size / settings.chunkSize);

					var spark = new sparkMd5.ArrayBuffer();

					var deferred = $q.defer();
					var promise = deferred.promise;

					var onLoadFn = function(event) {
						spark.append(event.target.result);

						deferred.notify({
							loaded: currentChunk * settings.chunkSize + event.loaded,
							total: file.size
						});

						currentChunk++;
						if (currentChunk < chunks) {
							loadData();
						} else {
							var md5sum = spark.end();
							deferred.resolve(md5sum);
						}
					};

					var onErrorFn = function (error) {
						deferred.reject(error);
					};

					var loadData = function() {
						var fileReader = new FileReader();
						fileReader.onload = onLoadFn;
						fileReader.onerror = onErrorFn;

						var start = currentChunk * settings.chunkSize;
						var end = ((start + settings.chunkSize) >= file.size) ? file.size : start + settings.chunkSize;

						fileReader.readAsArrayBuffer(slicer.call(file, start, end));
					};

					promise.success = function(fn) {
						promise.then(function(md5sum) {
							fn(md5sum);
						});

						return promise;
					};

					promise.error = function(fn) {
						promise.then(null, function(error) {
							fn(error);
						});

						return promise;
					};

					promise.progress = function(fn) {
						promise.then(null, null, function(stats) {
							fn(stats);
						});

						return promise;
					};

					loadData();

					return promise;
				}
			};

		}];

	}]);

	return moduleName;
}));