<?php
namespace W3TC;

/**
 * Windows Azure Storage CDN engine
 */
class CdnEngine_Azure extends CdnEngine_Base {
	/**
	 * Storage client object
	 *
	 * @var Microsoft_WindowsAzure_Storage_Blob
	 */
	var $_client = null;

	/**
	 * PHP5 Constructor
	 *
	 * @param array   $config
	 */
	function __construct( $config = array() ) {
		$config = array_merge( array(
				'user' => '',
				'key' => '',
				'container' => '',
				'cname' => array(),
			), $config );

		parent::__construct( $config );
	}

	/**
	 * Inits storage client object
	 *
	 * @param string  $error
	 * @return boolean
	 */
	function _init( &$error ) {
		if ( empty( $this->_config['user'] ) ) {
			$error = 'Empty account name.';

			return false;
		}

		if ( empty( $this->_config['key'] ) ) {
			$error = 'Empty account key.';

			return false;
		}

		if ( empty( $this->_config['container'] ) ) {
			$error = 'Empty container name.';

			return false;
		}

		set_include_path( get_include_path() . PATH_SEPARATOR . W3TC_LIB_DIR );

		require_once 'Microsoft/WindowsAzure/Storage/Blob.php';

		$this->_client = new \Microsoft_WindowsAzure_Storage_Blob(
			\Microsoft_WindowsAzure_Storage::URL_CLOUD_BLOB,
			$this->_config['user'],
			$this->_config['key'],
			false,
			\Microsoft_WindowsAzure_RetryPolicy_RetryPolicyAbstract::noRetry()
		);

		return true;
	}

	/**
	 * Uploads files to S3
	 *
	 * @param array   $files
	 * @param array   $results
	 * @param boolean $force_rewrite
	 * @return boolean
	 */
	function upload( $files, &$results, $force_rewrite = false,
		$timeout_time = NULL ) {
		$error = null;

		if ( !$this->_init( $error ) ) {
			$results = $this->_get_results( $files, W3TC_CDN_RESULT_HALT, $error );

			return false;
		}

		foreach ( $files as $file ) {
			if ( !is_null( $timeout_time ) && time() > $timeout_time )
				break;

			$remote_path = $file['remote_path'];

			$results[] = $this->_upload( $file, $force_rewrite );

			if ( $this->_config['compression'] && $this->_may_gzip( $remote_path ) ) {
				$file['remote_path_gzip'] = $remote_path . $this->_gzip_extension;

				$results[] = $this->_upload_gzip( $file, $force_rewrite );
			}
		}

		return !$this->_is_error( $results );
	}

	/**
	 * Uploads file
	 *
	 * @param string  $local_path
	 * @param string  $remote_path
	 * @param bool    $force_rewrite
	 * @return array
	 */
	function _upload( $file, $force_rewrite = false ) {
		$local_path = $file['local_path'];
		$remote_path = $file['remote_path'];

		if ( !file_exists( $local_path ) ) {
			return $this->_get_result( $local_path, $remote_path,
				W3TC_CDN_RESULT_ERROR, 'Source file not found.', $file );
		}

		$md5 = @md5_file( $local_path );
		$content_md5 = $this->_get_content_md5( $md5 );

		if ( !$force_rewrite ) {
			try {
				$properties = $this->_client->getBlobProperties( $this->_config['container'], $remote_path );
				$size = @filesize( $local_path );

				if ( $size === (int) $properties->Size && $content_md5 === $properties->ContentMd5 ) {
					return $this->_get_result( $local_path, $remote_path,
						W3TC_CDN_RESULT_OK, 'File up-to-date.', $file );
				}
			} catch ( \Exception $exception ) {
			}
		}

		$headers = $this->_get_headers( $file );
		$headers = array_merge( $headers, array(
				'Content-MD5' => $content_md5
			) );

		try {
			$this->_client->putBlob( $this->_config['container'], $remote_path, $local_path, array(), null, $headers );
		} catch ( \Exception $exception ) {
			return $this->_get_result( $local_path, $remote_path,
				W3TC_CDN_RESULT_ERROR,
				sprintf( 'Unable to put blob (%s).', $exception->getMessage() ),
				$file );
		}

		return $this->_get_result( $local_path, $remote_path, W3TC_CDN_RESULT_OK,
			'OK', $file );
	}

	/**
	 * Uploads gzipped file
	 *
	 * @param array   $file          CDN file array
	 * @param bool    $force_rewrite
	 * @return array
	 */
	function _upload_gzip( $file, $force_rewrite = false ) {
		$local_path = $file['local_path'];
		$remote_path = $file['remote_path_gzip'];

		if ( !function_exists( 'gzencode' ) ) {
			return $this->_get_result( $local_path, $remote_path,
				W3TC_CDN_RESULT_ERROR, "GZIP library doesn't exists.", $file );
		}

		if ( !file_exists( $local_path ) ) {
			return $this->_get_result( $local_path, $remote_path,
				W3TC_CDN_RESULT_ERROR, 'Source file not found.', $file );
		}

		$contents = @file_get_contents( $local_path );

		if ( $contents === false ) {
			return $this->_get_result( $local_path, $remote_path,
				W3TC_CDN_RESULT_ERROR, 'Unable to read file.', $file );
		}

		$data = gzencode( $contents );
		$md5 = md5( $data );
		$content_md5 = $this->_get_content_md5( $md5 );

		if ( !$force_rewrite ) {
			try {
				$properties = $this->_client->getBlobProperties( $this->_config['container'], $remote_path );
				$size = @filesize( $local_path );

				if ( $size === (int) $properties->Size && $content_md5 === $properties->ContentMd5 ) {
					return $this->_get_result( $local_path, $remote_path,
						W3TC_CDN_RESULT_OK, 'File up-to-date.', $file );
				}
			} catch ( \Exception $exception ) {
			}
		}

		$headers = $this->_get_headers( $file );
		$headers = array_merge( $headers, array(
				'Content-MD5' => $content_md5,
				'Content-Encoding' => 'gzip'
			) );

		try {
			$this->_client->putBlobData( $this->_config['container'], $remote_path, $data, array(), null, $headers );
		} catch ( \Exception $exception ) {
			return $this->_get_result( $local_path, $remote_path,
				W3TC_CDN_RESULT_ERROR,
				sprintf( 'Unable to put blob (%s).', $exception->getMessage() ),
				$file );
		}

		return $this->_get_result( $local_path, $remote_path,
			W3TC_CDN_RESULT_OK, 'OK', $file );
	}

	/**
	 * Deletes files from storage
	 *
	 * @param array   $files
	 * @param array   $results
	 * @return boolean
	 */
	function delete( $files, &$results ) {
		$error = null;

		if ( !$this->_init( $error ) ) {
			$results = $this->_get_results( $files, W3TC_CDN_RESULT_HALT, $error );

			return false;
		}

		foreach ( $files as $file ) {
			$local_path = $file['local_path'];
			$remote_path = $file['remote_path'];

			try {
				$this->_client->deleteBlob( $this->_config['container'], $remote_path );
				$results[] = $this->_get_result( $local_path, $remote_path,
					W3TC_CDN_RESULT_OK, 'OK', $file );
			} catch ( \Exception $exception ) {
				$results[] = $this->_get_result( $local_path, $remote_path,
					W3TC_CDN_RESULT_ERROR,
					sprintf( 'Unable to delete blob (%s).', $exception->getMessage() ),
					$file );
			}

			if ( $this->_config['compression'] ) {
				$remote_path_gzip = $remote_path . $this->_gzip_extension;

				try {
					$this->_client->deleteBlob( $this->_config['container'], $remote_path_gzip );
					$results[] = $this->_get_result( $local_path,
						$remote_path_gzip, W3TC_CDN_RESULT_OK, 'OK',
						$file );
				} catch ( \Exception $exception ) {
					$results[] = $this->_get_result( $local_path,
						$remote_path_gzip, W3TC_CDN_RESULT_ERROR,
						sprintf( 'Unable to delete blob (%s).',
							$exception->getMessage() ),
						$file );
				}
			}
		}

		return !$this->_is_error( $results );
	}

	/**
	 * Tests S3
	 *
	 * @param string  $error
	 * @return boolean
	 */
	function test( &$error ) {
		if ( !parent::test( $error ) ) {
			return false;
		}

		$string = 'test_azure_' . md5( time() );

		if ( !$this->_init( $error ) ) {
			return false;
		}

		try {
			$containers = $this->_client->listContainers();
		} catch ( \Exception $exception ) {
			$error = sprintf( 'Unable to list containers (%s).', $exception->getMessage() );

			return false;
		}

		$container = null;

		foreach ( (array) $containers as $_container ) {
			if ( $_container->Name == $this->_config['container'] ) {
				$container = $_container;
				break;
			}
		}

		if ( !$container ) {
			$error = sprintf( 'Container doesn\'t exist: %s.', $this->_config['container'] );

			return false;
		}

		try {
			$this->_client->putBlobData( $this->_config['container'], $string, $string );
		} catch ( \Exception $exception ) {
			$error = sprintf( 'Unable to put blob data (%s).', $exception->getMessage() );

			return false;
		}

		try {
			$data = $this->_client->getBlobData( $this->_config['container'], $string );
		} catch ( \Exception $exception ) {
			$error = sprintf( 'Unable to get blob data (%s).', $exception->getMessage() );

			return false;
		}

		if ( $data != $string ) {
			try {
				$this->_client->deleteBlob( $this->_config['container'], $string );
			} catch ( \Exception $exception ) {
			}

			$error = 'Blob datas are not equal.';

			return false;
		}

		try {
			$this->_client->deleteBlob( $this->_config['container'], $string );
		} catch ( \Exception $exception ) {
			$error = sprintf( 'Unable to delete blob (%s).', $exception->getMessage() );

			return false;
		}

		return true;
	}

	/**
	 * Returns CDN domain
	 *
	 * @return array
	 */
	function get_domains() {
		if ( !empty( $this->_config['cname'] ) ) {
			return (array) $this->_config['cname'];
		} elseif ( !empty( $this->_config['user'] ) ) {
			$domain = sprintf( '%s.blob.core.windows.net', $this->_config['user'] );

			return array(
				$domain
			);
		}

		return array();
	}

	/**
	 * Returns via string
	 *
	 * @return string
	 */
	function get_via() {
		return sprintf( 'Windows Azure Storage: %s', parent::get_via() );
	}

	/**
	 * Creates bucket
	 *
	 * @param string  $container_id
	 * @param string  $error
	 * @return boolean
	 */
	function create_container( &$container_id, &$error ) {
		if ( !$this->_init( $error ) ) {
			return false;
		}

		try {
			$containers = $this->_client->listContainers();
		} catch ( \Exception $exception ) {
			$error = sprintf( 'Unable to list containers (%s).', $exception->getMessage() );

			return false;
		}

		if ( in_array( $this->_config['container'], (array) $containers ) ) {
			$error = sprintf( 'Container already exists: %s.', $this->_config['container'] );

			return false;
		}

		try {
			$this->_client->createContainer( $this->_config['container'] );
			$this->_client->setContainerAcl( $this->_config['container'], \Microsoft_WindowsAzure_Storage_Blob::ACL_PUBLIC_BLOB );
		} catch ( \Exception $exception ) {
			$error = sprintf( 'Unable to create container: %s (%s)', $this->_config['container'], $exception->getMessage() );

			return false;
		}

		return true;
	}

	/**
	 * Returns Content-MD5 header value
	 *
	 * @param string  $string
	 * @return string
	 */
	function _get_content_md5( $md5 ) {
		return base64_encode( pack( 'H*', $md5 ) );
	}

	/**
	 * Formats object URL
	 *
	 * @param string  $path
	 * @return string
	 */
	function _format_url( $path ) {
		$domain = $this->get_domain( $path );

		if ( $domain && !empty( $this->_config['container'] ) ) {
			$scheme = $this->_get_scheme();
			$url = sprintf( '%s://%s/%s/%s', $scheme, $domain, $this->_config['container'], $path );

			return $url;
		}

		return false;
	}

	/**
	 * Returns array of headers
	 *
	 * @param array   $file CDN file array
	 * @return array
	 */
	function _get_headers( $file ) {
		$allowed_headers = array(
			'Content-Length',
			'Content-Type',
			'Content-Encoding',
			'Content-Language',
			'Content-MD5',
			'Cache-Control',
		);

		$headers = parent::_get_headers( $file, true );

		foreach ( $headers as $header => $value ) {
			if ( !in_array( $header, $allowed_headers ) ) {
				unset( $headers[$header] );
			}
		}

		return $headers;
	}

	/**
	 * How and if headers should be set
	 *
	 * @return string W3TC_CDN_HEADER_NONE, W3TC_CDN_HEADER_UPLOADABLE, W3TC_CDN_HEADER_MIRRORING
	 */
	function headers_support() {
		return W3TC_CDN_HEADER_UPLOADABLE;
	}

	function get_prepend_path( $path ) {
		$path = parent::get_prepend_path( $path );
		$path = $this->_config['container'] ? trim( $path, '/' ) . '/' . trim( $this->_config['container'], '/' ): $path;
		return $path;
	}
}