<?php
/*
 * Copyright 2010 Google Inc.
 *
 * 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.
 */

/**
 * WP based implementation of apiIO.
 *
 */
class Yoast_Google_WPIO extends Yoast_Google_IO {
	private static $ENTITY_HTTP_METHODS = array( "POST" => null, "PUT" => null );
	private static $HOP_BY_HOP = array(
		'connection', 'keep-alive', 'proxy-authenticate', 'proxy-authorization',
		'te', 'trailers', 'transfer-encoding', 'upgrade' );

	/**
	 * Perform an authenticated / signed apiHttpRequest.
	 * This function takes the apiHttpRequest, calls apiAuth->sign on it
	 * (which can modify the request in what ever way fits the auth mechanism)
	 * and then calls apiWPIO::makeRequest on the signed request
	 *
	 * @param Yoast_Google_HttpRequest $request
	 *
	 * @return Yoast_Google_HttpRequest The resulting HTTP response including the
	 * responseHttpCode, responseHeaders and responseBody.
	 */
	public function authenticatedRequest( Yoast_Google_HttpRequest $request ) {
		$request = Yoast_Google_Client::$auth->sign( $request );

		return $this->makeRequest( $request );
	}

	/**
	 * Execute a apiHttpRequest
	 *
	 * @param Yoast_Google_HttpRequest $request the http request to be executed
	 *
	 * @return Yoast_Google_HttpRequest http request with the response http code, response
	 * headers and response body filled in
	 */
	public function makeRequest( Yoast_Google_HttpRequest $request ) {

		// First, check to see if we have a valid cached version.
		$cached = $this->getCachedRequest( $request );
		if ( $cached !== false ) {
			if ( ! $this->checkMustRevaliadateCachedRequest( $cached, $request ) ) {
				return $cached;
			}
		}

		if ( array_key_exists( $request->getRequestMethod(),
			self::$ENTITY_HTTP_METHODS ) ) {
			$request = $this->processEntityRequest( $request );
		}

		$params = array(
			'user-agent' => $request->getUserAgent(),
			'timeout'    => 30,
			'sslverify'  => false,
		);

		$curl_version = $this->get_curl_version();
		if( $curl_version !== false ) {
			if ( version_compare( $curl_version, '7.19.0', '<=' ) && version_compare( $curl_version, '7.19.8', '>' ) ) {
				add_filter( 'http_api_transports', array( $this, 'filter_curl_from_transports' ) );
			}
		}

		if ( $request->getPostBody() ) {
			$params['body'] = $request->getPostBody();
		}

		$requestHeaders = $request->getRequestHeaders();
		if ( $requestHeaders && is_array( $requestHeaders ) ) {
			$params['headers'] = $requestHeaders;
		}


		switch ( $request->getRequestMethod() ) {
			case 'POST' :
				$response = wp_remote_post( $request->getUrl(), $params );
				break;

			case 'GET' :
				$response = wp_remote_get( $request->getUrl(), $params );
				break;
		}

		$responseBody    = wp_remote_retrieve_body( $response );
		$respHttpCode    = wp_remote_retrieve_response_code( $response );
		$responseHeaders = wp_remote_retrieve_headers( $response );

		if ( $respHttpCode == 304 && $cached ) {
			// If the server responded NOT_MODIFIED, return the cached request.
			$this->updateCachedRequest( $cached, $responseHeaders );

			return $cached;
		}

		// Fill in the apiHttpRequest with the response values
		$request->setResponseHttpCode( $respHttpCode );
		$request->setResponseHeaders( $responseHeaders );

		$request->setResponseBody( $responseBody );
		// Store the request in cache (the function checks to see if the request
		// can actually be cached)
		$this->setCachedRequest( $request );

		// And finally return it

		return $request;
	}

	/**
	 * Remove Curl from the transport
	 *
	 * @param $transports
	 *
	 * @return mixed
	 */
	public function filter_curl_from_transports( $transports ) {
		unset( $transports['curl'] );

		return $transports;
	}

	/**
	 * Set options that update default behavior.
	 *
	 * @param array $optParams Multiple options used by a session.
	 */
	public function setOptions( $optParams ) {

	}

	/**
	 * Get the current curl verison if curl is installed
	 *
	 * @return bool|string
	 */
	public function get_curl_version() {
		if ( function_exists( 'curl_version' ) ) {
			$curl = curl_version();

			if ( isset( $curl['version'] ) ) {
				return $curl['version'];
			}
		}

		return false;
	}

}
