<?php
/**
 * Copyright (c) 2009, RealDolmen
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of RealDolmen nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY RealDolmen ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL RealDolmen BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * @category   Microsoft
 * @package    Microsoft
 * @copyright  Copyright (c) 2009, RealDolmen (http://www.realdolmen.com)
 * @license    http://phpazure.codeplex.com/license
 */

namespace Akeeba\Engine\Postproc\Connector\Azure\Credentials;

// Protection against direct access
defined('AKEEBAENGINE') or die();

use Akeeba\Engine\Postproc\Connector\Azure\AzureStorage;
use Akeeba\Engine\Postproc\Connector\Azure\Credentials;
use Akeeba\Engine\Postproc\Connector\Azure\Http\Transport;

/**
 * @category   Microsoft
 * @package    Microsoft_WindowsAzure
 * @copyright  Copyright (c) 2009, RealDolmen (http://www.realdolmen.com)
 * @license    http://phpazure.codeplex.com/license
 */
class Sharedkey extends Credentials
{
	/**
	 * Sign request URL with credentials
	 *
	 * @param string $requestUrl         Request URL
	 * @param string $resourceType       Resource type
	 * @param string $requiredPermission Required permission
	 *
	 * @return string Signed request URL
	 */
	public function signRequestUrl($requestUrl = '', $resourceType = AzureStorage::RESOURCE_UNKNOWN, $requiredPermission = Credentials::PERMISSION_READ)
	{
		return $requestUrl;
	}

	/**
	 * Sign request headers with credentials
	 *
	 * @param string  $httpVerb           HTTP verb the request will use
	 * @param string  $path               Path for the request
	 * @param string  $queryString        Query string for the request
	 * @param array   $headers            x-ms headers to add
	 * @param boolean $forTableStorage    Is the request for table storage?
	 * @param string  $resourceType       Resource type
	 * @param string  $requiredPermission Required permission
	 *
	 * @return array Array of headers
	 */
	public function signRequestHeaders($httpVerb = Transport::VERB_GET, $path = '/', $queryString = '', $headers = null, $forTableStorage = false, $resourceType = AzureStorage::RESOURCE_UNKNOWN, $requiredPermission = Credentials::PERMISSION_READ)
	{
		// http://github.com/sriramk/winazurestorage/blob/214010a2f8931bac9c96dfeb337d56fe084ca63b/winazurestorage.py

		// Determine path
		if ($this->_usePathStyleUri)
		{
			$path = substr($path, strpos($path, '/'));
		}

		// Determine query
		$queryString = $this->prepareQueryStringForSigning($queryString);

		// Canonicalized headers
		$canonicalizedHeaders = array();

		// Request date
		$requestDate = '';
		if (isset($headers[self::PREFIX_STORAGE_HEADER . 'date']))
		{
			$requestDate = $headers[self::PREFIX_STORAGE_HEADER . 'date'];
		}
		else
		{
			$requestDate = gmdate('D, d M Y H:i:s', time()) . ' GMT'; // RFC 1123
			$canonicalizedHeaders[] = self::PREFIX_STORAGE_HEADER . 'date:' . $requestDate;
		}

		// Build canonicalized headers
		if (!is_null($headers))
		{
			foreach ($headers as $header => $value)
			{
				if (is_bool($value))
				{
					$value = $value === true ? 'True' : 'False';
				}

				$headers[$header] = $value;
				if (substr($header, 0, strlen(self::PREFIX_STORAGE_HEADER)) == self::PREFIX_STORAGE_HEADER)
				{
					$canonicalizedHeaders[] = strtolower($header) . ':' . $value;
				}
			}
		}
		sort($canonicalizedHeaders);

		// Build canonicalized resource string
		$canonicalizedResource = '/' . $this->_accountName;
		if ($this->_usePathStyleUri)
		{
			$canonicalizedResource .= '/' . $this->_accountName;
		}
		$canonicalizedResource .= $path;
		if ($queryString !== '')
		{
			$canonicalizedResource .= $queryString;
		}

		// Create string to sign
		$stringToSign = array();
		$stringToSign[] = strtoupper($httpVerb); // VERB
		$stringToSign[] = ""; // Content-MD5
		$stringToSign[] = ""; // Content-Type
		$stringToSign[] = "";
		// Date already in $canonicalizedHeaders
		// $stringToSign[] = self::PREFIX_STORAGE_HEADER . 'date:' . $requestDate; // Date

		if (!$forTableStorage && count($canonicalizedHeaders) > 0)
		{
			$stringToSign[] = implode("\n", $canonicalizedHeaders);
		} // Canonicalized headers

		$stringToSign[] = $canonicalizedResource; // Canonicalized resource
		$stringToSign = implode("\n", $stringToSign);
		$signString = base64_encode(hash_hmac('sha256', $stringToSign, $this->_accountKey, true));

		// Sign request
		$headers[self::PREFIX_STORAGE_HEADER . 'date'] = $requestDate;
		$headers['Authorization'] = 'SharedKey ' . $this->_accountName . ':' . $signString;

		// Return headers
		return $headers;
	}
}