/**
 * @file llxmlrpctransaction.cpp
 * @brief LLXMLRPCTransaction and related class implementations
 *
 * $LicenseInfo:firstyear=2006&license=viewerlgpl$
 * Second Life Viewer Source Code
 * Copyright (C) 2010, Linden Research, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation;
 * version 2.1 of the License only.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
 * $/LicenseInfo$
 */

#include "llviewerprecompiledheaders.h"
// include this to get winsock2 because openssl attempts to include winsock1
#include "llwin32headerslean.h"
#include <openssl/x509_vfy.h>
#include <openssl/ssl.h>
#include "llsecapi.h"

#include "llxmlrpctransaction.h"
#include "llxmlrpclistener.h"

#include "httpcommon.h"
#include "llhttpconstants.h"
#include "httprequest.h"
#include "httpoptions.h"
#include "httpheaders.h"
#include "bufferarray.h"
#include "llversioninfo.h"
#include "llviewercontrol.h"
#include "stringize.h"

// Have to include these last to avoid queue redefinition!

#ifdef LL_USESYSTEMLIBS
#include <xmlrpc.h>
#else
#include <xmlrpc-epi/xmlrpc.h>
#endif
// <xmlrpc-epi/queue.h> contains a harmful #define queue xmlrpc_queue. This
// breaks any use of std::queue. Ditch that #define: if any of our code wants
// to reference xmlrpc_queue, let it reference it directly.
#if defined(queue)
#undef queue
#endif

#include "llappviewer.h"
#include "lltrans.h"

#include "boost/move/unique_ptr.hpp"

namespace boost
{
    using ::boost::movelib::unique_ptr; // move unique_ptr into the boost namespace.
}

// Static instance of LLXMLRPCListener declared here so that every time we
// bring in this code, we instantiate a listener. If we put the static
// instance of LLXMLRPCListener into llxmlrpclistener.cpp, the linker would
// simply omit llxmlrpclistener.o, and shouting on the LLEventPump would do
// nothing.
static LLXMLRPCListener listener("LLXMLRPCTransaction");

LLXMLRPCValue LLXMLRPCValue::operator[](const char* id) const
{
    return LLXMLRPCValue(XMLRPC_VectorGetValueWithID(mV, id));
}

std::string LLXMLRPCValue::asString() const
{
    const char* s = XMLRPC_GetValueString(mV);
    return s ? s : "";
}

int     LLXMLRPCValue::asInt() const    { return XMLRPC_GetValueInt(mV); }
bool    LLXMLRPCValue::asBool() const   { return XMLRPC_GetValueBoolean(mV) != 0; }
double  LLXMLRPCValue::asDouble() const { return XMLRPC_GetValueDouble(mV); }

LLXMLRPCValue LLXMLRPCValue::rewind()
{
    return LLXMLRPCValue(XMLRPC_VectorRewind(mV));
}

LLXMLRPCValue LLXMLRPCValue::next()
{
    return LLXMLRPCValue(XMLRPC_VectorNext(mV));
}

bool LLXMLRPCValue::isValid() const
{
    return mV != NULL;
}

LLXMLRPCValue LLXMLRPCValue::createArray()
{
    return LLXMLRPCValue(XMLRPC_CreateVector(NULL, xmlrpc_vector_array));
}

LLXMLRPCValue LLXMLRPCValue::createStruct()
{
    return LLXMLRPCValue(XMLRPC_CreateVector(NULL, xmlrpc_vector_struct));
}


void LLXMLRPCValue::append(LLXMLRPCValue& v)
{
    XMLRPC_AddValueToVector(mV, v.mV);
}

void LLXMLRPCValue::appendString(const std::string& v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueString(NULL, v.c_str(), 0));
}

void LLXMLRPCValue::appendInt(int v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueInt(NULL, v));
}

void LLXMLRPCValue::appendBool(bool v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueBoolean(NULL, v));
}

void LLXMLRPCValue::appendDouble(double v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueDouble(NULL, v));
}


void LLXMLRPCValue::append(const char* id, LLXMLRPCValue& v)
{
    XMLRPC_SetValueID(v.mV, id, 0);
    XMLRPC_AddValueToVector(mV, v.mV);
}

void LLXMLRPCValue::appendString(const char* id, const std::string& v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueString(id, v.c_str(), 0));
}

void LLXMLRPCValue::appendInt(const char* id, int v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueInt(id, v));
}

void LLXMLRPCValue::appendBool(const char* id, bool v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueBoolean(id, v));
}

void LLXMLRPCValue::appendDouble(const char* id, double v)
{
    XMLRPC_AddValueToVector(mV, XMLRPC_CreateValueDouble(id, v));
}

void LLXMLRPCValue::cleanup()
{
    XMLRPC_CleanupValue(mV);
    mV = NULL;
}

XMLRPC_VALUE LLXMLRPCValue::getValue() const
{
    return mV;
}


class LLXMLRPCTransaction::Handler : public LLCore::HttpHandler
{
public:
    Handler(LLCore::HttpRequest::ptr_t &request, LLXMLRPCTransaction::Impl *impl);
    virtual ~Handler();

    virtual void onCompleted(LLCore::HttpHandle handle, LLCore::HttpResponse * response);

    typedef std::shared_ptr<LLXMLRPCTransaction::Handler> ptr_t;

private:

    LLXMLRPCTransaction::Impl *mImpl;
    LLCore::HttpRequest::ptr_t mRequest;
};

class LLXMLRPCTransaction::Impl
{
public:
    typedef LLXMLRPCTransaction::EStatus    EStatus;

    LLCore::HttpRequest::ptr_t  mHttpRequest;


    EStatus             mStatus;
    CURLcode            mCurlCode;
    std::string         mStatusMessage;
    std::string         mStatusURI;
    LLCore::HttpResponse::TransferStats::ptr_t  mTransferStats;
    Handler::ptr_t      mHandler;
    LLCore::HttpHandle  mPostH;

    std::string         mURI;

    std::string         mProxyAddress;

    std::string         mResponseText;
    XMLRPC_REQUEST      mResponse;
    std::string         mCertStore;
    LLSD mErrorCertData;

    Impl(const std::string& uri, XMLRPC_REQUEST request, bool useGzip, const LLSD& httpParams);
    Impl(const std::string& uri,
        const std::string& method, LLXMLRPCValue params, bool useGzip);
    ~Impl();

    bool process();

    void setStatus(EStatus code, const std::string& message = "", const std::string& uri = "");
    void setHttpStatus(const LLCore::HttpStatus &status);

private:
    void init(XMLRPC_REQUEST request, bool useGzip, const LLSD& httpParams);
};

LLXMLRPCTransaction::Handler::Handler(LLCore::HttpRequest::ptr_t &request,
        LLXMLRPCTransaction::Impl *impl) :
    mImpl(impl),
    mRequest(request)
{
}

LLXMLRPCTransaction::Handler::~Handler()
{
}

void LLXMLRPCTransaction::Handler::onCompleted(LLCore::HttpHandle handle,
    LLCore::HttpResponse * response)
{
    LLCore::HttpStatus status = response->getStatus();

    if (!status)
    {
        mImpl->setHttpStatus(status);
        LLSD errordata = status.getErrorData();
        mImpl->mErrorCertData = errordata;

        if ((status.toULong() != CURLE_SSL_PEER_CERTIFICATE) &&
            (status.toULong() != CURLE_SSL_CACERT))
        {
            // if we have a curl error that's not already been handled
            // (a non cert error), then generate the warning message as
            // appropriate
            LL_WARNS() << "LLXMLRPCTransaction error "
                << status.toHex() << ": " << status.toString() << LL_ENDL;
            LL_WARNS() << "LLXMLRPCTransaction request URI: "
                << mImpl->mURI << LL_ENDL;
        }

        return;
    }

    mImpl->setStatus(LLXMLRPCTransaction::StatusComplete);
    mImpl->mTransferStats = response->getTransferStats();

    // the contents of a buffer array are potentially noncontiguous, so we
    // will need to copy them into an contiguous block of memory for XMLRPC.
    LLCore::BufferArray *body = response->getBody();
    char * bodydata = new char[body->size()];

    body->read(0, bodydata, body->size());

    mImpl->mResponse = XMLRPC_REQUEST_FromXML(bodydata, static_cast<int>(body->size()), 0);

    delete[] bodydata;

    bool        hasError = false;
    bool        hasFault = false;
    int         faultCode = 0;
    std::string faultString;

    LLXMLRPCValue error(XMLRPC_RequestGetError(mImpl->mResponse));
    if (error.isValid())
    {
        hasError = true;
        faultCode = error["faultCode"].asInt();
        faultString = error["faultString"].asString();
    }
    else if (XMLRPC_ResponseIsFault(mImpl->mResponse))
    {
        hasFault = true;
        faultCode = XMLRPC_GetResponseFaultCode(mImpl->mResponse);
        faultString = XMLRPC_GetResponseFaultString(mImpl->mResponse);
    }

    if (hasError || hasFault)
    {
        mImpl->setStatus(LLXMLRPCTransaction::StatusXMLRPCError);

        LL_WARNS() << "LLXMLRPCTransaction XMLRPC "
            << (hasError ? "error " : "fault ")
            << faultCode << ": "
            << faultString << LL_ENDL;
        LL_WARNS() << "LLXMLRPCTransaction request URI: "
            << mImpl->mURI << LL_ENDL;
    }

}

//=========================================================================

LLXMLRPCTransaction::Impl::Impl(const std::string& uri,
        XMLRPC_REQUEST request, bool useGzip, const LLSD& httpParams)
    : mHttpRequest(),
      mStatus(LLXMLRPCTransaction::StatusNotStarted),
      mURI(uri),
      mResponse(0)
{
    init(request, useGzip, httpParams);
}


LLXMLRPCTransaction::Impl::Impl(const std::string& uri,
        const std::string& method, LLXMLRPCValue params, bool useGzip)
    : mHttpRequest(),
      mStatus(LLXMLRPCTransaction::StatusNotStarted),
      mURI(uri),
      mResponse(0)
{
    XMLRPC_REQUEST request = XMLRPC_RequestNew();
    XMLRPC_RequestSetMethodName(request, method.c_str());
    XMLRPC_RequestSetRequestType(request, xmlrpc_request_call);
    XMLRPC_RequestSetData(request, params.getValue());

    init(request, useGzip, LLSD());
    // DEV-28398: without this XMLRPC_RequestFree() call, it looks as though
    // the 'request' object is simply leaked. It's less clear to me whether we
    // should also ask to free request value data (second param 1), since the
    // data come from 'params'.
    XMLRPC_RequestFree(request, 1);
}

void LLXMLRPCTransaction::Impl::init(XMLRPC_REQUEST request, bool useGzip, const LLSD& httpParams)
{
    LLCore::HttpOptions::ptr_t httpOpts;
    LLCore::HttpHeaders::ptr_t httpHeaders;


    if (!mHttpRequest)
    {
        mHttpRequest = LLCore::HttpRequest::ptr_t(new LLCore::HttpRequest);
    }

    // LLRefCounted starts with a 1 ref, so don't add a ref in the smart pointer
    httpOpts = LLCore::HttpOptions::ptr_t(new LLCore::HttpOptions());

    // delay between repeats will start from 5 sec and grow to 20 sec with each repeat
    httpOpts->setMinBackoff(5E6L);
    httpOpts->setMaxBackoff(20E6L);

    httpOpts->setTimeout(httpParams.has("timeout") ? httpParams["timeout"].asInteger() : 40L);
    if (httpParams.has("retries"))
    {
        httpOpts->setRetries(httpParams["retries"].asInteger());
    }
    if (httpParams.has("DNSCacheTimeout"))
    {
        httpOpts->setDNSCacheTimeout(httpParams["DNSCacheTimeout"].asInteger());
    }

    bool vefifySSLCert = !gSavedSettings.getBOOL("NoVerifySSLCert");
    mCertStore = gSavedSettings.getString("CertStore");

    httpOpts->setSSLVerifyPeer( vefifySSLCert );
    httpOpts->setSSLVerifyHost( vefifySSLCert ? 2 : 0);

    // LLRefCounted starts with a 1 ref, so don't add a ref in the smart pointer
    httpHeaders = LLCore::HttpHeaders::ptr_t(new LLCore::HttpHeaders());

    httpHeaders->append(HTTP_OUT_HEADER_CONTENT_TYPE, HTTP_CONTENT_TEXT_XML);

    std::string user_agent = stringize(
        LLVersionInfo::instance().getChannel(), ' ',
        LLVersionInfo::instance().getMajor(), '.',
        LLVersionInfo::instance().getMinor(), '.',
        LLVersionInfo::instance().getPatch(), " (",
        LLVersionInfo::instance().getBuild(), ')');

    httpHeaders->append(HTTP_OUT_HEADER_USER_AGENT, user_agent);

    ///* Setting the DNS cache timeout to -1 disables it completely.
    //This might help with bug #503 */
    //httpOpts->setDNSCacheTimeout(-1);

    LLCore::BufferArray::ptr_t body = LLCore::BufferArray::ptr_t(new LLCore::BufferArray());

    // TODO: See if there is a way to serialize to a preallocated buffer I'm
    // not fond of the copy here.
    int requestSize(0);
    char * requestText = XMLRPC_REQUEST_ToXML(request, &requestSize);

    body->append(requestText, requestSize);

    XMLRPC_Free(requestText);

    mHandler = LLXMLRPCTransaction::Handler::ptr_t(new Handler( mHttpRequest, this ));

    mPostH = mHttpRequest->requestPost(LLCore::HttpRequest::DEFAULT_POLICY_ID,
        mURI, body.get(), httpOpts, httpHeaders, mHandler);

}


LLXMLRPCTransaction::Impl::~Impl()
{
    if (mResponse)
    {
        XMLRPC_RequestFree(mResponse, 1);
    }
}

bool LLXMLRPCTransaction::Impl::process()
{
    if (!mPostH || !mHttpRequest)
    {
        LL_WARNS() << "transaction failed." << LL_ENDL;
        return true; //failed, quit.
    }

    switch (mStatus)
    {
        case LLXMLRPCTransaction::StatusComplete:
        case LLXMLRPCTransaction::StatusCURLError:
        case LLXMLRPCTransaction::StatusXMLRPCError:
        case LLXMLRPCTransaction::StatusOtherError:
        {
            return true;
        }

        case LLXMLRPCTransaction::StatusNotStarted:
        {
            setStatus(LLXMLRPCTransaction::StatusStarted);
            break;
        }

        default:
            break;
    }

    LLCore::HttpStatus status = mHttpRequest->update(0);

    status = mHttpRequest->getStatus();
    if (!status)
    {
        return false;
    }

    return false;
}

void LLXMLRPCTransaction::Impl::setStatus(EStatus status,
    const std::string& message, const std::string& uri)
{
    mStatus = status;
    mStatusMessage = message;
    mStatusURI = uri;

    if (mStatusMessage.empty())
    {
        switch (mStatus)
        {
            case StatusNotStarted:
                mStatusMessage = "(not started)";
                break;

            case StatusStarted:
                mStatusMessage = "(waiting for server response)";
                break;

            case StatusDownloading:
                mStatusMessage = "(reading server response)";
                break;

            case StatusComplete:
                mStatusMessage = "(done)";
                break;
            default:
                // Usually this means that there's a problem with the login server,
                // not with the client.  Direct user to status page.
                mStatusMessage = LLTrans::getString("server_is_down");
                mStatusURI = "http://status.secondlifegrid.net/";
        }
    }
}

void LLXMLRPCTransaction::Impl::setHttpStatus(const LLCore::HttpStatus &status)
{
    CURLcode code = static_cast<CURLcode>(status.toULong());
    std::string message;
    std::string uri = "http://support.secondlife.com";
    LLURI failuri(mURI);
    LLStringUtil::format_map_t args;

    switch (code)
    {
    case CURLE_COULDNT_RESOLVE_HOST:
        args["[HOSTNAME]"] = failuri.hostName();
        message = LLTrans::getString("couldnt_resolve_host", args);
        break;

#if CURLE_SSL_PEER_CERTIFICATE != CURLE_SSL_CACERT
    case CURLE_SSL_PEER_CERTIFICATE:
        message = LLTrans::getString("ssl_peer_certificate");
        break;
#endif
    case CURLE_SSL_CACERT:
    case CURLE_SSL_CONNECT_ERROR:
        message = LLTrans::getString("ssl_connect_error");
        break;

    default:
        break;
    }

    mCurlCode = code;
    setStatus(StatusCURLError, message, uri);

}


LLXMLRPCTransaction::LLXMLRPCTransaction(
    const std::string& uri, XMLRPC_REQUEST request, bool useGzip, const LLSD& httpParams)
: impl(* new Impl(uri, request, useGzip, httpParams))
{ }


LLXMLRPCTransaction::LLXMLRPCTransaction(
    const std::string& uri,
    const std::string& method, LLXMLRPCValue params, bool useGzip)
: impl(* new Impl(uri, method, params, useGzip))
{ }

LLXMLRPCTransaction::~LLXMLRPCTransaction()
{
    delete &impl;
}

bool LLXMLRPCTransaction::process()
{
    return impl.process();
}

LLXMLRPCTransaction::EStatus LLXMLRPCTransaction::status(int* curlCode)
{
    if (curlCode)
    {
        *curlCode =
            (impl.mStatus == StatusCURLError)
                ? impl.mCurlCode
                : CURLE_OK;
    }

    return impl.mStatus;
}

std::string LLXMLRPCTransaction::statusMessage()
{
    return impl.mStatusMessage;
}

LLSD LLXMLRPCTransaction::getErrorCertData()
{
    return impl.mErrorCertData;
}

std::string LLXMLRPCTransaction::statusURI()
{
    return impl.mStatusURI;
}

XMLRPC_REQUEST LLXMLRPCTransaction::response()
{
    return impl.mResponse;
}

LLXMLRPCValue LLXMLRPCTransaction::responseValue()
{
    return LLXMLRPCValue(XMLRPC_RequestGetData(impl.mResponse));
}


F64 LLXMLRPCTransaction::transferRate()
{
    if (impl.mStatus != StatusComplete)
    {
        return 0.0L;
    }

    double rate_bits_per_sec = impl.mTransferStats->mSpeedDownload * 8.0;

    LL_INFOS("AppInit") << "Buffer size:   " << impl.mResponseText.size() << " B" << LL_ENDL;
    LL_DEBUGS("AppInit") << "Transfer size: " << impl.mTransferStats->mSizeDownload << " B" << LL_ENDL;
    LL_DEBUGS("AppInit") << "Transfer time: " << impl.mTransferStats->mTotalTime << " s" << LL_ENDL;
    LL_INFOS("AppInit") << "Transfer rate: " << rate_bits_per_sec / 1000.0 << " Kb/s" << LL_ENDL;

    return rate_bits_per_sec;
}