WebRequestHandle.h

// Copyright eeGeo Ltd (2012-2014), All Rights Reserved

#pragma once

#include "Web.h"
#include "Cache.h"
#include "ICallback.h"
#include "Types.h"

#include <curl.h>
#include <string>

namespace Eegeo
{
    namespace Web
    {
        namespace WebHandleCompletionCode
        {
            enum Values
            {
                // Equivalent to HTTP 200 OK, full response returned.
                Success,

                // Equivalent to HTTP 304 Not Modified in response to conditional get.
                NotModified,

                // Request failed.
                Failed,

                Cancelled
            };
        }

        struct HandleCompletedResult
        {
            WebHandleCompletionCode::Values CompletionCode;
            bool CanFallBackToCache;
            bool RetryPossible;
            int HttpResponseCode;

            HandleCompletedResult()
            : CompletionCode(WebHandleCompletionCode::Failed)
            , CanFallBackToCache(false)
            , RetryPossible(false)
            , HttpResponseCode(0)
            {}
        };

        typedef int TWebRequestHandleId;

        class WebRequestHandle : private Eegeo::NonCopyable
        {
        public:
            WebRequestHandle(const TWebRequestHandleId handleId, const std::string& caCertFilePath);
            ~WebRequestHandle();

            CURL* GetCurlHandle() const;
            bool IsInUse() const;
            std::string GetUrl() const;
            bool IsCancelled() const;

            // mutable
            void Use(InFlightWebRequest* pWebLoadRequest);
            
            void AppendBodyData(Byte* data, size_t size);
            void AppendHeaderData(Byte* data, size_t size);

            HandleCompletedResult HandleCompleted(CURLcode curlTransferReturnCode);

            InFlightWebRequest* GetInFlightWebRequest();
            TWebRequestHandleId GetHandleId() const;
            void Reset();
            
        private:

            void SetupCurlOptions();
            void WritePostData();
            void WriteMultipartFormData();
            void WriteMultipartFormField(curl_httppost** httpPost, const std::string& fieldName, const WebPostData& fieldData);
            void WriteMultipartFormText(curl_httppost** httpPost, const std::string& fieldName, const WebPostData& fieldData);
            void WriteMultipartFormBinary(curl_httppost** httpPost, const std::string& fieldName, const WebPostData& fieldData);
            void WriteHeaders();
            
            static size_t ReadCallback(void *ptr, size_t size, size_t nmemb, void *stream);
            
            bool ValidateHeaders();

            const TWebRequestHandleId m_handleId;
            CURL* m_pHandle;
            curl_slist* m_pCurlHeaderChunk;
            curl_httppost* m_pCurlFormPost;

            InFlightWebRequest* m_pInFlightWebRequest;

            std::string m_caCertFilePath;
            bool m_caCertRequired;
        };
    }
}