/**
 * Amazon S3 REST Wrapper
 * Version Date: 2015-09-03
 *
 * Copyright 2015 CF Webtools | cfwebtools.com
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * Derived from "Amazon S3 REST Wrapper" (http://amazons3.riaforge.org) by Joe Danziger (joe@ajaxcf.com)
 * Requires Adobe ColdFusion 10+ equivalent (tested in Adobe ColdFusion 11)
 *
 * Currently uses Signature Version 2. (http://docs.aws.amazon.com/AmazonS3/latest/dev/RESTAuthentication.html)
 * Needs to be upgraded to Version 4. (http://docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-authenticating-requests.html)
 */

component accessors=true {

	/**
	 * if using FW/1 & DI/1, arguments are populated using variables.framework.diConfig.constants in Application.cfc
	 */
	S3 function init( required string S3AccessKey, required string S3SecretAccessKey ) {
		variables.S3AccessKey = arguments.S3AccessKey;
		variables.S3SecretAccessKey = arguments.S3SecretAccessKey;
		return this;
	}

	/**
	 * NSA SHA-1 Algorithm to hash a message being sent to AWS using the secret key.
	 * Thanks to Adam Cameron and @jcberquist for help
	 */
	private binary function HMAC_SHA1( required string signKey, required string signMessage ) {

		// returns in hex
		var result = HMac( arguments.signMessage, arguments.signKey, 'HMACSHA1');

		// convert to binary and return
		return binaryDecode( result, 'hex' );
	}

	string function createSignature( required string stringIn) {

		// replace "\n" with "chr(10)" to get a correct digest
		var fixedData = replace( arguments.stringIn, "\n", chr(10), "all" );

		// calculate the hash of the information
		var digest = HMAC_SHA1(variables.S3SecretAccessKey, fixedData);

		// fix the returned data to be a proper signature
		var signature = toBase64(digest);

		return signature;

	}

	/**
	 * puts an object into the bucket
	 * ex: putObject( bucketName = 'myBucket', ACL = 'private', keyName = 'test.jpg', uploadDir = 'D:\', serverSideEncryption = 'AES256');
	 * AWS S3 REST API: http://docs.aws.amazon.com/AmazonS3/latest/API/RESTObjectPUT.html
	 * AWS S3 Meta Data: http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html
	 * @ACL the canned ACL to apply to the object ( private | public-read | public-read-write | authenticated-read | bucket-owner-read | bucket-owner-full-control )
	 * @cacheControl cache the object in your CloudFront cache service for better performance. Additional fees may apply.
	 * @cacheDays how many days the object will stay in the CloudFront. Max: 100 years
	 * @contentType a standard MIME type describing the format of the contents
	 * @fileName file name to retrieve for upload (ex: myFile.jpg). If left empty it uses the keyName attribute
	 * @keyName uniquely identifies the object in the S3 bucket. Unicode characters whose UTF-8 encoding is at most 1024 bytes long. Safe: [0-9], [a-z], [A-Z], !, -, _, ., *, ', (, and ). "/" infers a folder in the S3 console.
	 * @serverSideEncryption server-side encryption algorithm to use when S3 creates an object ( none | AES256 )
	 * @storageClass ( STANDARD | REDUCED_REDUNDANCY (noncritical, reproducible data at lower levels of redundancy) )
	 * @uploadDir local path the fileName attribute is stored including trailing "/"
	 */
	void function putObject(
		required string bucketName,
		string contentType = 'binary/octet-stream',
		boolean cacheControl = false,
		numeric cacheDays = 30,
		string ACL = 'public-read',
		string storageClass = 'STANDARD',
		required string keyName,
		string fileName = arguments.keyName,
		string uploadDir = expandPath('./'),
		string serverSideEncryption = 'none;'
	) {
		var versionID = '';
		var binaryFileData = '';
		var dateTimeString = getHTTPTimeString( now() );
		var cs = '';
		var signature = '';
		var httpService = '';
		var cacheSeconds = cacheDays * 24 * 60 * 60;
		var result = '';

		// put HTTP-Verb, Content-MD5(none), Content-Type and Date into signature
		cs = "PUT\n\n#arguments.contentType#\n#dateTimeString#\n";
		// add CanonicalizedAmzHeaders sorted lexicographically seperated by a new line
		cs &= "x-amz-acl:#arguments.acl#\n";
		if(arguments.serverSideEncryption == 'AES256') {
			cs &= "x-amz-server-side-encryption:AES256\n";
		}
		cs &= "x-amz-storage-class:#arguments.storageClass#\n";
		// add CanonicalizedResource
		cs &= "/#arguments.bucketName#/#arguments.keyName#";

		// hash the signature
		signature = createSignature(cs);

		// read the file data into a variable
		// TODO: might need also use "ToBase64" per CF docs
		binaryFileData = fileReadBinary( arguments.uploadDir & arguments.fileName );

		// send the file to amazon
		httpService = new http();

		httpService.setMethod('PUT');
		httpService.setURL('https://#arguments.bucketName#.s3.amazonaws.com/#arguments.keyName#');

		httpService.addParam( type = 'header', name = 'Authorization', value = 'AWS #variables.S3AccessKey#:#signature#' );
		httpService.addParam( type = 'header', name = 'Content-Type', value = arguments.contentType );
		httpService.addParam( type = 'header', name = 'Date', value = dateTimeString );
		httpService.addParam( type = 'header', name = 'x-amz-acl', value = arguments.acl );
		httpService.addParam( type = 'header', name = 'x-amz-storage-class', value = arguments.storageClass );
		if(arguments.serverSideEncryption == 'AES256') {
			httpService.addParam( type = 'header', name = 'x-amz-server-side-encryption', value = 'AES256' );
		}
		if (arguments.cacheControl) {
			httpService.addParam( type = 'header', name = 'Cache-Control', value = 'max-age=#cacheSeconds#' );
		}
		httpService.addParam( type = 'body', value = binaryFileData);

		result = httpService.send();
	}

	/**
	 * returns a link to an object
	 * if you generate a link to a file that doesn't exist, an XML error will be returned with the code "AccessDenied", instead
	 * of a not found error, upon accessing the URL
	 */
	string function getObjectLink( required string bucketName, required string keyName, string minutesValid = 1 ) {
		var timedAmazonLink = "";
		var epochTime = dateDiff( "s", DateConvert("utc2Local", "January 1 1970 00:00"), now() ) + (arguments.minutesValid * 60);

		// create a canonical string to send
		var cs = "GET\n\n\n#epochTime#\n/#arguments.bucketName#/#arguments.keyName#";

		// hash the signature
		var signature = createSignature(cs);

		timedAmazonLink = "https://#arguments.bucketName#.s3.amazonaws.com/#arguments.keyName#?AWSAccessKeyId=#URLEncodedFormat(variables.S3AccessKey)#&Expires=#epochTime#&Signature=#URLEncodedFormat(signature)#";

		return timedAmazonLink;
	}

	/**
	 * Download the file. Returns full file path.
	 * @file file name to be given to saved file
	 * @path physical path to store file including trailing slash (ex: c:\myfiles\)
	 */
	 string function getObject( required string bucketName, required string keyName, string path = expandPath('./') ) {
	 	var httpService = new http();

		httpService.setMethod('GET');
		httpService.setURL( getObjectLink( bucketName = arguments.bucketName, keyName = arguments.keyName ) );
		httpService.setPath(arguments.path);
		httpService.setFile(arguments.keyName);

		httpService.send();

		return arguments.path & arguments.keyName;
	 }

	/**
	 * Deletes an object
	 */
	void function deleteObject( required string bucketName, required string keyName ) {

		var httpService = '';
		var dateTimeString = GetHTTPTimeString( Now() );

		// create a canonical string to send based on operation requested
		var cs = "DELETE\n\n\n#dateTimeString#\n/#arguments.bucketName#/#arguments.keyName#";

		// create a proper signature
		var signature = createSignature(cs);

		// delete the object via REST
		httpService = new http();

		httpService.setMethod('DELETE');
		httpService.setURL('https://#arguments.bucketName#.s3.amazonaws.com/#arguments.keyName#');
		httpService.addParam( type = 'header', name = 'Date', value = dateTimeString );
		httpService.addParam( type = 'header', name = 'Authorization', value = 'AWS #variables.S3AccessKey#:#signature#' );

		httpService.send();

	}
}