(function () {
    'use strict';
    //service that handles uploading of files and images
    var serviceId = 'fileUpload';
    angular.module('app').factory(serviceId, ['config', '$q', '$upload', 'user', fileUpload]);

    function fileUpload(config, $q, $upload, user) {
        var service = {
            uploadFile: uploadFile,
            uploadImage: uploadImage
        };

        return service;


        //upload an image
        function uploadImage(obj, file, success, progress, error, uploadPath) {

            user.getProfile().then(function (theUser) {
                var data = {
                    upload_preset: config.cloudinaryUploadPreset,
                    tags: 'myimages,' + theUser.id
                };
                //images are uploaded to Cloudinary   
                $upload.upload({
                    url: config.cloudinaryApiBaseUrl + config.cloudinaryName + uploadPath,
                    data: data,
                    file: file
                }).progress(function (e) {
                    var percent = Math.round((e.loaded * 100.0) / e.total);
                    return progress(percent);
                }).success(function (data, status, headers, config) {
                    return success(obj, data);
                }).error(function (data) {
                    return error();
                });
            });
        }

        //upload a (non-image) file
        function uploadFile(fileItem, file, success, progress, error, container) {
            user.getProfile().then(function (theUser) {
                //upload to azure blob storage
                return uploadToBlob(fileItem, file, success, progress, error, container);
            });
        }

        //get the url of the Azure blob bucket to upload files to
        function getBucketUploadUrl(fileName, container) {
     
            fileName = fileName.replace("#", "");
            fileName = fileName.replace(" ", "");
            fileName = fileName.replace(")", "");
            fileName = fileName.replace("(", "");

            if (container) {
                return config.azureBlobUrl + container + '/' + fileName;
            } else {
                return config.azureBlobUrl + config.uploadBucketName + '/' + fileName;
            }
        }

        //we use Azure blob storage to upload files to - get the Azure Blob url for the file
        function getBlobUploadUrl(fileName, container) {
            //get the base url of blob storage
            var baseUrl = getBucketUploadUrl(fileName, container);
            //get the SAS (Secure Access Signature) token from cache (this signature allows us write access permissions to Azure Blob storage - so we can write the file there)
            var sas = user.getUploadBucketSasCached();
            if (sas) {
                //check if the SAS token is still valid, if it is use the token - using moment.js for easy calculation of times
                var expiry = moment(sas.expiryTime).subtract('seconds', '30'); //30 seconds to allow for small differences in time calculations between machines
                if (expiry.isAfter(moment())) {
                    var deferred = $q.defer();
                    deferred.resolve({ baseUrl: baseUrl, fullUrl: baseUrl + sas.sas });
                    return deferred.promise;
                }
            }
            if (config.appCode == 'OB' || config.appCode == 'CUPPA') {
                return user.getUploadBucketSasForContainerMyUsers(container).then(function (sas) {
                    return {
                        baseUrl: baseUrl,
                        fullUrl: baseUrl + sas.sas
                    };
                });
            }
            //we don't have a valid existing SAS so get the sas from the server
            if (container) {
                return user.getUploadBucketSasForContainer(container).then(function (sas) {
                    return {
                        baseUrl: baseUrl,
                        fullUrl: baseUrl + sas.sas
                    };
                });
            } else {
                return user.getUploadBucketSas().then(function (sas) {
                    return {
                        baseUrl: baseUrl,
                        fullUrl: baseUrl + sas.sas
                    };
                });
            }
        }

        //upload the file to blob storage (Azure)
        function uploadToBlob(fileItem, file, success, progress, error, container) {
            //first get the upload URL
            getBlobUploadUrl(fileItem.fileName, container).then(function (urls) {
                var fileReader = new FileReader();
                fileItem.fileUrl = urls.baseUrl;
                fileItem.isDropBoxFile = false;
                fileReader.readAsArrayBuffer(file);
                //use the $upload service to write the file as part of an HTTP PUT request to Azure Blob storage
                fileReader.onload = function (e) {
                    $upload.http({
                        url: urls.fullUrl,
                        method: 'PUT',
                        headers: { //azure needs these extra headers
                            'x-ms-blob-type': 'BlockBlob',
                            'Content-Type': file.type
                        },
                        data: e.target.result
                    }).progress(function (e) { //inform the user what progress we are making on the upload
                        var percent = Math.round((e.loaded * 100.0) / e.total);
                        return progress(percent);
                    }).success(function (data, status, headers, config) {
                        return success(fileItem, data);
                    }).error(function (data) {
                        return error();
                    });
                }
            });
        }
    }
})();