<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Service_WindowsAzure
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: SharedKey.php 23775 2011-03-01 17:25:24Z ralph $
 */

/**
 * @see Zend_Service_WindowsAzure_Credentials_CredentialsAbstract
 */
require_once 'Zend/Service/WindowsAzure/Credentials/CredentialsAbstract.php';

/**
 * @see Zend_Service_WindowsAzure_Storage
 */
require_once 'Zend/Service/WindowsAzure/Storage.php';

/**
 * @see Zend_Http_Client
 */
require_once 'Zend/Http/Client.php';

/**
 * @see Zend_Service_WindowsAzure_Credentials_Exception
 */
require_once 'Zend/Service/WindowsAzure/Credentials/Exception.php';

/**
 * @category   Zend
 * @package    Zend_Service_WindowsAzure
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Service_WindowsAzure_Credentials_SharedKey
    extends Zend_Service_WindowsAzure_Credentials_CredentialsAbstract
{
    /**
     * 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 = Zend_Service_WindowsAzure_Storage::RESOURCE_UNKNOWN,
        $requiredPermission = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::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
     * @param mixed  $rawData Raw post data
     * @return array Array of headers
     */
    public function signRequestHeaders(
        $httpVerb = Zend_Http_Client::GET,
        $path = '/',
        $queryString = '',
        $headers = null,
        $forTableStorage = false,
        $resourceType = Zend_Service_WindowsAzure_Storage::RESOURCE_UNKNOWN,
        $requiredPermission = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PERMISSION_READ,
        $rawData = null
    ) {
        // http://github.com/sriramk/winazurestorage/blob/214010a2f8931bac9c96dfeb337d56fe084ca63b/winazurestorage.py

        // Table storage?
        if ($forTableStorage) {
            throw new Zend_Service_WindowsAzure_Credentials_Exception('The Windows Azure SDK for PHP does not support SharedKey authentication on table storage. Use SharedKeyLite authentication instead.');
        }
        
        // 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[Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PREFIX_STORAGE_HEADER . 'date'])) {
            $requestDate = $headers[Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PREFIX_STORAGE_HEADER . 'date'];
        } else {
            $requestDate = gmdate('D, d M Y H:i:s', time()) . ' GMT'; // RFC 1123
            $canonicalizedHeaders[] = Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PREFIX_STORAGE_HEADER . 'date:' . $requestDate;
        }
        
        // Build canonicalized headers
        if ($headers !== null) {
            foreach ($headers as $header => $value) {
                if (is_bool($value)) {
                    $value = $value === true ? 'True' : 'False';
                }

                $headers[$header] = $value;
                if (substr($header, 0, strlen(Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PREFIX_STORAGE_HEADER)) == Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::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 !== '') {
            $queryStringItems = $this->_makeArrayOfQueryString($queryString);
            foreach ($queryStringItems as $key => $value) {
                $canonicalizedResource .= "\n" . strtolower($key) . ':' . $value;
            }
        }
        
        // Content-Length header
        $contentLength = '';
        if (strtoupper($httpVerb) != Zend_Http_Client::GET
             && strtoupper($httpVerb) != Zend_Http_Client::DELETE
             && strtoupper($httpVerb) != Zend_Http_Client::HEAD) {
            $contentLength = 0;
            
            if ($rawData !== null) {
                $contentLength = strlen($rawData);
            }
        }

		// Create string to sign
		$stringToSign   = array();
		$stringToSign[] = strtoupper($httpVerb); 									// VERB
    	$stringToSign[] = $this->_issetOr($headers, 'Content-Encoding', '');		// Content-Encoding
    	$stringToSign[] = $this->_issetOr($headers, 'Content-Language', '');		// Content-Language
    	$stringToSign[] = $contentLength; 											// Content-Length
    	$stringToSign[] = $this->_issetOr($headers, 'Content-MD5', '');				// Content-MD5
    	$stringToSign[] = $this->_issetOr($headers, 'Content-Type', '');			// Content-Type
    	$stringToSign[] = "";														// Date
    	$stringToSign[] = $this->_issetOr($headers, 'If-Modified-Since', '');		// If-Modified-Since
    	$stringToSign[] = $this->_issetOr($headers, 'If-Match', '');				// If-Match
    	$stringToSign[] = $this->_issetOr($headers, 'If-None-Match', '');			// If-None-Match
    	$stringToSign[] = $this->_issetOr($headers, 'If-Unmodified-Since', '');		// If-Unmodified-Since
    	$stringToSign[] = $this->_issetOr($headers, 'Range', '');					// Range
    	
    	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[Zend_Service_WindowsAzure_Credentials_CredentialsAbstract::PREFIX_STORAGE_HEADER . 'date'] = $requestDate;
        $headers['Authorization'] = 'SharedKey ' . $this->_accountName . ':' . $signString;
        
        // Return headers
        return $headers;
    }
}
