<?php
/*
 * Copyright 2014 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.
 */
/**
 * Curl based implementation of Google_IO.
 *
 * @author Stuart Langley <slangley@google.com>
 */
require_once realpath(dirname(__FILE__) . '/../../../autoload.php');

class Google_IO_Curl extends Google_IO_Abstract
{
    // cURL hex representation of version 7.30.0
    const NO_QUIRK_VERSION = 0x071E00;

    private $options = array();

    /**
     * Execute an HTTP Request
     *
     * @param Google_HttpRequest $request
     *            the http request to be executed
     * @return Google_HttpRequest http request with the response http code,
     *         response headers and response body filled in
     * @throws Google_IO_Exception on curl or IO error
     */
    public function executeRequest(Google_Http_Request $request)
    {
        $curl = curl_init();
        if ($request->getPostBody()) {
            curl_setopt($curl, CURLOPT_POSTFIELDS, $request->getPostBody());
        }
        $requestHeaders = $request->getRequestHeaders();
        if ($requestHeaders && is_array($requestHeaders)) {
            $curlHeaders = array();
            foreach ($requestHeaders as $k => $v) {
                $curlHeaders[] = "$k: $v";
            }
            curl_setopt($curl, CURLOPT_HTTPHEADER, $curlHeaders);
        }
        curl_setopt($curl, CURLOPT_URL, $request->getUrl());
        curl_setopt($curl, CURLOPT_CUSTOMREQUEST, $request->getRequestMethod());
        curl_setopt($curl, CURLOPT_USERAGENT, $request->getUserAgent());
        curl_setopt($curl, CURLOPT_FOLLOWLOCATION, false);
        curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, true);
        // 1 is CURL_SSLVERSION_TLSv1, which is not always defined in PHP.
        curl_setopt($curl, CURLOPT_SSLVERSION, 1);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($curl, CURLOPT_HEADER, true);
        if ($request->canGzip()) {
            curl_setopt($curl, CURLOPT_ENCODING, 'gzip,deflate');
        }
        $options = $this->client->getClassConfig('Google_IO_Curl', 'options');
        if (is_array($options)) {
            $this->setOptions($options);
        }
        foreach ($this->options as $key => $var) {
            curl_setopt($curl, $key, $var);
        }
        if (! isset($this->options[CURLOPT_CAINFO])) {
            curl_setopt($curl, CURLOPT_CAINFO, dirname(__FILE__) . '/cacerts.pem');
        }
        $this->client->getLogger()->debug('cURL request', array(
            'url' => $request->getUrl(),
            'method' => $request->getRequestMethod(),
            'headers' => $requestHeaders,
            'body' => $request->getPostBody()
        ));
        $response = curl_exec($curl);
        if ($response === false) {
            $error = curl_error($curl);
            $this->client->getLogger()->error('cURL ' . $error);
            throw new Google_IO_Exception($error);
        }
        $headerSize = curl_getinfo($curl, CURLINFO_HEADER_SIZE);
        list ($responseHeaders, $responseBody) = $this->parseHttpResponse($response, $headerSize);
        $responseCode = curl_getinfo($curl, CURLINFO_HTTP_CODE);
        $this->client->getLogger()->debug('cURL response', array(
            'code' => $responseCode,
            'headers' => $responseHeaders,
            'body' => $responseBody
        ));
        return array(
            $responseBody,
            $responseHeaders,
            $responseCode
        );
    }

    /**
     * Set options that update the transport implementation's behavior.
     *
     * @param
     *            $options
     */
    public function setOptions($options)
    {
        $this->options = $options + $this->options;
    }

    /**
     * Set the maximum request time in seconds.
     *
     * @param $timeout in
     *            seconds
     */
    public function setTimeout($timeout)
    {
        // Since this timeout is really for putting a bound on the time
        // we'll set them both to the same. If you need to specify a longer
        // CURLOPT_TIMEOUT, or a tigher CONNECTTIMEOUT, the best thing to
        // do is use the setOptions method for the values individually.
        $this->options[CURLOPT_CONNECTTIMEOUT] = $timeout;
        $this->options[CURLOPT_TIMEOUT] = $timeout;
    }

    /**
     * Get the maximum request time in seconds.
     *
     * @return timeout in seconds
     */
    public function getTimeout()
    {
        return $this->options[CURLOPT_TIMEOUT];
    }

    /**
     * Test for the presence of a cURL header processing bug
     *
     * {@inheritDoc}
     *
     * @return boolean
     */
    protected function needsQuirk()
    {
        $ver = curl_version();
        $versionNum = $ver['version_number'];
        return $versionNum < Google_IO_Curl::NO_QUIRK_VERSION;
    }
}
