define(['localassetmanager', 'cameraRoll'], function (localAssetManager, cameraRoll) {
    'use strict';

    return function (connectionManager) {

        var self = this;

        self.uploadImages = function (server) {

            return cameraRoll.getFiles().then(function (photos) {

                if (!photos.length) {
                    return Promise.resolve();
                }

                var apiClient = connectionManager.getApiClient(server.Id);

                return apiClient.getContentUploadHistory().then(function (uploadHistory) {

                    photos = getFilesToUpload(photos, uploadHistory);

                    console.log('Found ' + photos.length + ' files to upload');

                    return new Promise(function (resolve, reject) {

                        uploadNext(photos, 0, server, apiClient, resolve, reject);
                    });

                }, function () {
                    return Promise.resolve();
                });

            });
        };

        function getFilesToUpload(files, uploadHistory) {

            return files.filter(function (file) {

                // Seeing some null entries for some reason
                if (!file) {
                    return false;
                }

                return uploadHistory.FilesUploaded.filter(function (u) {

                    return getUploadId(file) === u.Id;

                }).length === 0;
            });
        }

        function getUploadId(file) {
            return CryptoJS.SHA1(file + "1").toString();
        }

        function uploadNext(files, index, server, apiClient, resolve, reject) {

            var length = files.length;

            if (index >= length) {

                resolve();
                return;
            }

            uploadFile(files[index], apiClient).then(function () {

                uploadNext(files, index + 1, server, apiClient, resolve, reject);
            }, function () {
                uploadNext(files, index + 1, server, apiClient, resolve, reject);
            });
        }

        function uploadFile(file, apiClient) {

            return new Promise(function (resolve, reject) {

                require(['fileupload', "cryptojs-sha1"], function (FileUpload) {

                    var name = 'camera image ' + new Date().getTime();

                    var url = apiClient.getUrl('Devices/CameraUploads', {
                        DeviceId: apiClient.deviceId(),
                        Name: name,
                        Album: 'Camera Roll',
                        Id: getUploadId(file),
                        api_key: apiClient.accessToken()
                    });

                    console.log('Uploading file to ' + url);

                    new FileUpload().upload(file, name, url).then(resolve, reject);
                });
            });
        }
    };
});