/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011 Cyan Worlds, Inc.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.

Additional permissions under GNU GPL version 3 section 7

If you modify this Program, or any covered work, by linking or
combining it with any of RAD Game Tools Bink SDK, Autodesk 3ds Max SDK,
NVIDIA PhysX SDK, Microsoft DirectX SDK, OpenSSL library, Independent
JPEG Group JPEG library, Microsoft Windows Media SDK, or Apple QuickTime SDK
(or a modified version of those libraries),
containing parts covered by the terms of the Bink SDK EULA, 3ds Max EULA,
PhysX SDK EULA, DirectX SDK EULA, OpenSSL and SSLeay licenses, IJG
JPEG Library README, Windows Media SDK EULA, or QuickTime SDK EULA, the
licensors of this Program grant you additional
permission to convey the resulting work. Corresponding Source for a
non-source form of such a combination shall include the source code for
the parts of OpenSSL and IJG JPEG Library used as well as that of the covered
work.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/
#include "plBackgroundDownloader.h"

#include <process.h>

#include "../pnUtils/pnUtils.h"
#include "../pnNetBase/pnNetBase.h"
#include "../plEncryption/plChecksum.h"

#include "../NucleusLib/inc/hsResMgr.h"

#include "../plAgeDescription/plAgeManifest.h"
#include "../plResMgr/plResManager.h"
#include "../plFile/plFileUtils.h"
#include "../plFile/plEncryptedStream.h"
#include "../plCompression/plZlibStream.h"
#include "../plAudioCore/plAudioFileReader.h"
#include "../plProgressMgr/plProgressMgr.h"

#include "../pnAsyncCore/pnAsyncCore.h"
#include "../pnNetCli/pnNetCli.h"
#include "../plNetGameLib/plNetGameLib.h"

#include "../pnDispatch/plDispatch.h"
#include "../plStatusLog/plStatusLog.h"

static const unsigned kMaxDownloadTries = 10;
static const wchar s_manifest[] = L"AllAges";

plBackgroundDownloader* plBackgroundDownloader::fInstance = NULL;

hsBool gUseBackgroundDownloader = false;

//============================================================================
enum DownloaderLogType
{
	kHeader,
	kInfo,
	kMajorStatus,
	kStatus,
	kError,
};
void BackgroundDownloaderLog(DownloaderLogType type, const char* format, ...)
{
	UInt32 color = 0;
	switch (type)
	{
	case kHeader:		color = plStatusLog::kWhite;	break;
	case kInfo:			color = plStatusLog::kBlue;		break;
	case kMajorStatus:	color = plStatusLog::kYellow;	break;
	case kStatus:		color = plStatusLog::kGreen;	break;
	case kError:		color = plStatusLog::kRed;		break;
	}

	static plStatusLog* gStatusLog = nil;
	if (!gStatusLog)
	{
		gStatusLog = plStatusLogMgr::GetInstance().CreateStatusLog(
			20,
			"bgdownload.log",
			plStatusLog::kFilledBackground | plStatusLog::kAlignToTop | plStatusLog::kDeleteForMe);
	}

	va_list args;
	va_start(args, format);

	gStatusLog->AddLineV(color, format, args);

	va_end(args);
}

//============================================================================
class plBGDownloadStream : public plZlibStream
{
public:
	plBGDownloadStream() : plZlibStream() {}
	virtual ~plBGDownloadStream() {}

	virtual UInt32 Write(UInt32 byteCount, const void* buffer);
};

UInt32 plBGDownloadStream::Write(UInt32 byteCount, const void* buffer)
{
	return plZlibStream::Write(byteCount, buffer);
}

//============================================================================
static void DownloadFileCallback(ENetError result, void* param, const wchar filename[], hsStream* writer)
{
	plBackgroundDownloader* bgdownloader = (plBackgroundDownloader*)param;

	// Retry download unless shutting down or file not found
	switch (result) {
		case kNetSuccess:
			writer->Close();
			bgdownloader->DoneWithFile(true);
		break;
		
		case kNetErrFileNotFound:
		case kNetErrRemoteShutdown:
			writer->Close();
			bgdownloader->DoneWithFile(false);
		break;
		
		default:
			writer->Rewind();
			NetCliFileDownloadRequest(
				filename,
				writer,
				DownloadFileCallback,
				param
			);
		break;
	}
}

static void ManifestCallback(ENetError result, void* param, const wchar group[], const NetCliFileManifestEntry manifest[], unsigned entryCount)
{
	plBackgroundDownloader* bgdownloader = (plBackgroundDownloader*)param;
	bgdownloader->DoneWithManifest(result == kNetSuccess, manifest, entryCount);
}

//============================================================================
plBackgroundDownloader* plBackgroundDownloader::GetInstance()
{
    return fInstance;
}

void plBackgroundDownloader::ThreadMain(void * param)
{
	Init();

	plBackgroundDownloader::GetInstance()->Run();
	plBackgroundDownloader::GetInstance()->CleanUp();

	Shutdown();
}

void plBackgroundDownloader::StartThread()
{
	_beginthread(plBackgroundDownloader::ThreadMain, 0, NULL);
}

void plBackgroundDownloader::Init()
{
	fInstance = TRACKED_NEW plBackgroundDownloader();
}

void plBackgroundDownloader::Shutdown()
{
	delete fInstance;
	fInstance = NULL;
}

plBackgroundDownloader::plBackgroundDownloader()
{
	BackgroundDownloaderLog(kHeader, "--- Starting background download ---");

	fBGDownloaderRun = CreateEvent(
		NULL,				// default security attributes
		TRUE,				// manual-reset event
		FALSE,				// initial state is signaled
		NULL				// unnamed
	);

	fBGDownloaderIsPaused = CreateEvent(
		NULL,				// default security attributes
		FALSE,				// manual-reset event
		TRUE,				// initial state is signaled
		NULL				// unnamed
	);
}

plBackgroundDownloader::~plBackgroundDownloader()
{
	HANDLE runHandle = fBGDownloaderRun;
	fBGDownloaderRun = NULL;
	CloseHandle(runHandle);
	
	HANDLE pausedHandle = fBGDownloaderIsPaused;
	fBGDownloaderIsPaused = NULL;
	CloseHandle(pausedHandle);

	BackgroundDownloaderLog(kHeader, "--- Background download done ---");
}

UInt32 plBackgroundDownloader::IGetDownloadSize()
{
	if (!IGetDataManifest())
		return 0;

	UInt32 downloadSize = 0;
	UInt32 downloadFiles = 0;
	for (MfsFileVec::iterator i = fMfsVec.begin(); i != fMfsVec.end(); ++i)
	{
		plManifestFile* mfsFile = (*i);
		
		if (!mfsFile->IsLocalUpToDate())
		{
			downloadFiles++;
			downloadSize += mfsFile->GetDownloadSize();
		}
	}

	BackgroundDownloaderLog(kInfo, "Got download stats, %d files, %d bytes", downloadFiles, downloadSize);

	return downloadSize;
}

bool plBackgroundDownloader::CheckFreeSpace(UInt32 bytesNeeded)
{
#ifdef HS_BUILD_FOR_WIN32
	ULARGE_INTEGER freeBytesAvailable, totalNumberOfBytes, neededBytes;
	if (GetDiskFreeSpaceEx(NULL, &freeBytesAvailable, &totalNumberOfBytes, NULL))
	{
		neededBytes.HighPart = 0;
		neededBytes.LowPart = bytesNeeded;

		if (neededBytes.QuadPart > freeBytesAvailable.QuadPart)
		{
			BackgroundDownloaderLog(kInfo, "Not enough disk space (asked for %d bytes)", bytesNeeded);
			return false;
		}
	}
#endif // HS_BUILD_FOR_WIN32

	return true;
}

bool plBackgroundDownloader::IDecompressSound(plManifestFile* mfsFile, bool noOverwrite)
{
	UInt32 flags = mfsFile->GetFlags();

	if ( (hsCheckBits(flags, plManifestFile::kSndFlagCacheSplit) ||	hsCheckBits(flags, plManifestFile::kSndFlagCacheStereo)) && stricmp(plFileUtils::GetFileExt(mfsFile->GetName()), "ogg") == 0)
	{
		plAudioFileReader* reader = plAudioFileReader::CreateReader(mfsFile->GetName(), plAudioCore::kAll, plAudioFileReader::kStreamNative);
		if (!reader)
		{
			BackgroundDownloaderLog(kInfo, "Unable to create audio file reader for %s", mfsFile->GetName());
			return false;
		}

		UInt32 size = reader->GetDataSize();
		delete reader;

		// Make sure we have enough free space
		if (!CheckFreeSpace(size))
			return false;

		if (hsCheckBits(flags, plManifestFile::kSndFlagCacheSplit))
			plAudioFileReader::CacheFile(mfsFile->GetName(), true, noOverwrite);
		if (hsCheckBits(flags, plManifestFile::kSndFlagCacheStereo))
			plAudioFileReader::CacheFile(mfsFile->GetName(), false, noOverwrite);
	}

	return true;
}

bool plBackgroundDownloader::Run()
{
	// Wait to be signaled that we've gotten at least as far as the startup age
	WaitForSingleObject(fBGDownloaderRun, INFINITE);

	IGetDataManifest();

	plFileUtils::CreateDir("dat");
	plFileUtils::CreateDir("sfx");

	bool result = true;
	plResManager* resMgr = ((plResManager*)hsgResMgr::ResMgr());

	for (MfsFileVec::iterator i = fMfsVec.begin(); i != fMfsVec.end(); ++i)
	{
		plManifestFile* mfsFile = (*i);

		if (!mfsFile->IsLocalUpToDate())
		{
			if (!CheckFreeSpace(mfsFile->GetDiskSize()))
				return false;

			FileType type = IGetFile(mfsFile);
			if (type == kPrp)
			{
				// Checks for existence before attempting to remove
				resMgr->RemoveSinglePage(mfsFile->GetName());
				if (!resMgr->FindSinglePage(mfsFile->GetName()))
				{
					resMgr->AddSinglePage(mfsFile->GetName());
				}
			}
			else if (type == kOther)
			{
				if (!IDecompressSound(mfsFile, false))
				{
					char text[MAX_PATH];
					StrPrintf(text, arrsize(text), "%s could not be decompressed", mfsFile->GetName());
					BackgroundDownloaderLog(kInfo, text );
					hsAssert(false, text);
					result = false;
				}
			}
			else
			{
				char text[MAX_PATH];
				StrPrintf(text, arrsize(text), "Failed downloading file: %s", mfsFile->GetName());
				BackgroundDownloaderLog(kInfo, text );
				hsAssert(false, text);
				result = false;
			}
		}
	}

	return result;
}

void plBackgroundDownloader::CleanUp()
{
	BackgroundDownloaderLog(kMajorStatus, "Cleaning up background downloader..." );

	for (MfsFileVec::iterator i = fMfsVec.begin(); i != fMfsVec.end(); ++i)
	{
		plManifestFile* file = (*i);
		delete file;
	}
	fMfsVec.clear();
}

void plBackgroundDownloader::Pause()
{
	if (fBGDownloaderRun != NULL && fBGDownloaderIsPaused != NULL)
	{
		ResetEvent(fBGDownloaderRun);
		WaitForSingleObject(fBGDownloaderIsPaused, INFINITE);

		BackgroundDownloaderLog(kStatus, "--- Background download paused ---");
	}
}

void plBackgroundDownloader::UnPause()
{
	if (fBGDownloaderRun != NULL && fBGDownloaderIsPaused != NULL)
	{
		SetEvent(fBGDownloaderRun);

		BackgroundDownloaderLog(kStatus, "--- Background download resumed ---");
	}
}

plBackgroundDownloader::FileType plBackgroundDownloader::IGetFile(const plManifestFile* mfsFile)
{
	BackgroundDownloaderLog(kInfo, "    Setting up to download file %s", mfsFile->GetName());

	bool downloadDone = false;
	wchar* wServerPath = hsStringToWString(mfsFile->GetServerPath());
	int numTries = 0;

	while (!downloadDone)
	{
		if (WaitForSingleObject(fBGDownloaderRun, 0) == WAIT_TIMEOUT)
			SignalObjectAndWait(fBGDownloaderIsPaused, fBGDownloaderRun, INFINITE, FALSE);

		if (numTries >= kMaxDownloadTries)
		{
			BackgroundDownloaderLog(kInfo, "    Max download tries exceeded (%d). Aborting download...", kMaxDownloadTries);
			return kFail;
		}

		plBGDownloadStream* downloadStream = TRACKED_NEW plBGDownloadStream();
		if (!downloadStream->Open(mfsFile->GetName(), "wb"))
		{
			BackgroundDownloaderLog(kInfo, "    Unable to create file. Aborting download...");
			return kFail;
		}

		BackgroundDownloaderLog(kInfo, "    Downloading file %s...", mfsFile->GetName());
		
		fSuccess = false;	
		fDoneWithFile = false;
		NetCliFileDownloadRequest(
			wServerPath,
			downloadStream,
			DownloadFileCallback,
			this
		);

		while (!fDoneWithFile) {
			AsyncSleep(100);
		}

		if (!fSuccess) {
			// remove partial file and die (server didn't have the file or server is shutting down)
			plFileUtils::RemoveFile(mfsFile->GetName(), true);
			BackgroundDownloaderLog(kError, "      File %s failed to download.", mfsFile->GetName());
		}
		else {
			AsyncSleep(100);
			if (downloadStream->DecompressedOk()) {
				BackgroundDownloaderLog(kInfo, "      Decompress successful." );
				// download and decompress successful, do a md5 check on the resulting file
				plMD5Checksum localMD5(mfsFile->GetName());
				if (localMD5 != mfsFile->GetChecksum()) {
					plFileUtils::RemoveFile(mfsFile->GetName(), true);
					BackgroundDownloaderLog(kError, "      File %s MD5 check FAILED.", mfsFile->GetName());
					// don't set downloadDone so we attempt to re-download from the server
				}
				else {
					BackgroundDownloaderLog(kInfo, "      MD5 check succeeded.");
					downloadDone = true;
				}
			}
			else {
				plFileUtils::RemoveFile(mfsFile->GetName(), true);
				BackgroundDownloaderLog(kError, "      File %s failed to decompress.", mfsFile->GetName());
				// don't set downloadDone so we attempt to re-download from the server
			}
		}

		delete downloadStream;

		++numTries;
	}
	delete [] wServerPath;

	if (!fSuccess)	
		return kFail;
	
	if (stricmp(plFileUtils::GetFileExt(mfsFile->GetName()), "prp") == 0)
		return kPrp;

	return kOther;
}

bool plBackgroundDownloader::IGetDataManifest()
{
	if (fMfsVec.size() > 0)
		return true;

	BackgroundDownloaderLog(kMajorStatus, "Downloading new manifest from data server..." );

	fSuccess = false;
	unsigned numTries = 0;
	while (!fSuccess)
	{
		numTries++;
		fDoneWithFile = false;
		NetCliFileManifestRequest(ManifestCallback, this, s_manifest);
		while (!fDoneWithFile)
		{
			NetClientUpdate();
			plgDispatch::Dispatch()->MsgQueueProcess();
			AsyncSleep(10);
		}

		if (!fSuccess)
		{
			fMfsVec.clear(); // clear out any bad data
			if (numTries > kMaxDownloadTries)
				break; // abort
		}
	}

	if (fSuccess)
		BackgroundDownloaderLog(kStatus, "New manifest read; number of files: %d", fMfsVec.size() );
	else
		BackgroundDownloaderLog(kStatus, "Failed to download manifest after trying %d times", kMaxDownloadTries);

	return fSuccess;
}

void plBackgroundDownloader::DoneWithFile(bool success)
{
	fDoneWithFile = true;
	fSuccess = success;
}

void plBackgroundDownloader::DoneWithManifest(bool success, const NetCliFileManifestEntry manifestEntires[], unsigned entryCount)
{
	BackgroundDownloaderLog(kStatus, "New age manifest received. Reading...");
	
	if (success)
	{
		for (unsigned i = 0; i < entryCount; i++)
		{
			char* name = hsWStringToString(manifestEntires[i].clientName);
			char* serverPath = hsWStringToString(manifestEntires[i].downloadName);
			char* md5Str = hsWStringToString(manifestEntires[i].md5);
			int size = manifestEntires[i].fileSize;
			int zipsize = manifestEntires[i].zipSize;
			int flags = manifestEntires[i].flags;
			if (stricmp(plFileUtils::GetFileExt(name), "gz"))
				flags |= plManifestFile::kFlagZipped; // add zipped flag if necessary

			plMD5Checksum sum;
			sum.SetFromHexString(md5Str);
			fMfsVec.push_back(TRACKED_NEW plManifestFile(name, serverPath, sum, size, zipsize, flags, false));

			delete [] name;
			delete [] serverPath;
			delete [] md5Str;
		}
	}

	fDoneWithFile = true;
	fSuccess = success;
}