HttpsConnection::HttpsConnection()
{
	hInternet		= NULL;
	hRequest		= NULL;
	hSession		= NULL;
	agentName		= "";
	targetPort		= INTERNET_DEFAULT_HTTPS_PORT;
	securityFlags	= INTERNET_FLAG_RELOAD|INTERNET_FLAG_KEEP_CONNECTION|INTERNET_FLAG_NO_CACHE_WRITE
					  |INTERNET_FLAG_SECURE|INTERNET_FLAG_IGNORE_CERT_CN_INVALID;
}

bool HttpsConnection::connectToHttpsServer(string httpVerb)
{
	try {	
		hInternet = InternetOpenA(agentName.c_str()
								 ,INTERNET_OPEN_TYPE_PRECONFIG
								 ,NULL
								 ,NULL
								 ,0);
		if (!hInternet) {
			ERROR("HttpsConnection::connectToHttpsServer()","Unable to open internet (code " + str(GetLastError()) + ")");
			return false;
		}
		hSession = InternetConnectA(hInternet 
								   ,targetUrl.c_str()
								   ,targetPort
								   ,""
								   ,""
								   ,INTERNET_SERVICE_HTTP
								   ,0
								   ,0);
		if (!hSession) {
			ERROR("HttpsConnection::connectToHttpsServer()","Unable to connect to internet (code " + str(GetLastError()) + ")");
			clearHandles();
			return false;
		}
		hRequest = HttpOpenRequestA(hSession
								   ,httpVerb.c_str()
								   ,targetHost.c_str()
								   ,NULL
								   ,""
								   ,NULL
								   ,securityFlags
								   ,0);
		if (!hRequest) {
			ERROR("HttpsConnection::connectToHttpsServer()","Cannot perform HTTP request (code " + str(GetLastError()) + ")");
			clearHandles();		
			return false;
		}

	}
	catch (...) {
		ERROR("HttpsConnection::connectToHttpsServer()","Memory exception (code " + str(GetLastError()) + ")");
		return false;
	}

	return true;
}

static string get_utf8(const std::wstring &wstr)
{
    int sz = WideCharToMultiByte(CP_UTF8,0,&wstr[0],-1,0,0,0,0);
    std::string res(sz,0);
    WideCharToMultiByte(CP_UTF8,0,&wstr[0],-1,&res[0],sz,0,0);
    return res;
}

// if just going to read a response and don't need to send any data, leave args empty,
//	otherwise provide one or more headers and then one of either text *or* binary data (the latter
//	I added for protobuf use, since it won't survive the wstring/UTF8 conversion,
//	nor is it necessary)
bool HttpsConnection::sendHttpsRequest(const string& sendHeaders, const string& sendContentText, string* sendContentBinary)
{
	try {	
		for (int tries = 0; tries < 20; ++tries) {
			int result;
			if (sendContentText.empty()
				&& !sendContentBinary)
				result = HttpSendRequest(hRequest,NULL,0,NULL,0);
			else {
				std::wstring sendHeadersWide(sendHeaders.begin(),sendHeaders.end());
				if (!sendContentText.empty()) {
					std::wstring sendContentWide(sendContentText.begin(),sendContentText.end());
					string data = get_utf8(sendContentWide);
					result = HttpSendRequest(hRequest,sendHeadersWide.c_str(),sendHeadersWide.size(),&data[0],data.size());
				}
				else // binary
					result = HttpSendRequest(hRequest,sendHeadersWide.c_str(),sendHeadersWide.size(),&(*sendContentBinary)[0],sendContentBinary->size());
			}
			if (result) {
				if (!checkResponseHeader())
					return false;
				return true;
			}
			ERROR("HttpsConnection::sendHttpsRequest()","Cannot perform HTTP request (code " + str(GetLastError()) + ")"); // will get this if no internet connection
			return false;
		} 
	}
	catch (...) {
		ERROR("HttpsConnection::sendHttpsRequest()","Memory exception (code " + str(GetLastError()) + ")");
		return false;
	}
	return false;
}

string HttpsConnection::getRequestResult()
{
	DWORD	numberBytesRead;
	char	sz[1024];
	string	strResult;
	int		result; 
	do {
		result = InternetReadFile(hRequest,sz,1023,&numberBytesRead);												
		sz[numberBytesRead] = '\0';
		int x = strlen(sz);
		strResult += sz;
		memset(sz,0,1024);
	} while (result
			 && (numberBytesRead != 0));	
	return strResult;
}

void HttpsConnection::clearHandles()
{
	if (hInternet) {
		InternetCloseHandle(hInternet);
		hInternet = NULL;
	}
	if (hSession) {
		InternetCloseHandle(hSession);
		hSession = NULL;
	}
}

// confirm no issues with the latest response header,
//	returns true if okay, false if error
// header is saved in HttpsConnection::responseHeader for reference (mainly while debugging)
bool HttpsConnection::checkResponseHeader()
{
	LPVOID lpOutBuffer = NULL;
	DWORD dwSize = 0;

	goto_retryQuery:

	// this call will fail on the first pass, b/c no buffer is allocated
	if (!HttpQueryInfo(hRequest,HTTP_QUERY_RAW_HEADERS_CRLF,(LPVOID)lpOutBuffer,&dwSize,NULL)) {
		if (GetLastError() == ERROR_HTTP_HEADER_NOT_FOUND)
			return true; // header not available
		else {
			// check for insufficient buffer
			if (GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
				lpOutBuffer = new char[dwSize]; // allocate required buffer size
				goto goto_retryQuery; // try again
			}
			else { // error
				if (lpOutBuffer)
					delete [] lpOutBuffer;
				return false;
			}
		}
	}

	if (lpOutBuffer) {
		// convert to string via wstring
		wchar_t* t = (wchar_t*)lpOutBuffer;
		std::wstring responseHeaderWide = std::wstring(t);
		responseHeader.assign(responseHeaderWide.begin(),responseHeaderWide.end());
		delete [] lpOutBuffer;

		if (responseHeader.find("HTTP/1.1 200") == string::npos) {
			ERROR("HttpsConnection::checkResponseHeader()","Connection failed, server response " + string(responseHeader.begin()+9,responseHeader.begin()+12)); // extract specific response code, which should be at that position
			return false;
		}
	}

	return true;
}