/*
crashhandler.c - advanced crashhandler
Copyright (C) 2016 Mittorn

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.
*/

#include <winnt.h>
#include <dbghelp.h>
#include <psapi.h>
#include <time.h>

#include "platform/platform.h"
#include "input.h"

#define DBGHELP 1 // we always enable dbghelp.dll on Windows targets

#if DBGHELP
#ifndef XASH_SDL
typedef ULONG_PTR DWORD_PTR, *PDWORD_PTR;
#endif

static int Sys_ModuleName( HANDLE process, char *name, void *address, int len )
{
	DWORD_PTR   baseAddress = 0;
	static HMODULE     *moduleArray;
	static unsigned int moduleCount;
	LPBYTE      moduleArrayBytes;
	DWORD       bytesRequired;
	int i;

	if( len < 3 )
		return 0;

	if( !moduleArray && EnumProcessModules( process, NULL, 0, &bytesRequired ) )
	{
		if ( bytesRequired )
		{
			moduleArrayBytes = (LPBYTE)LocalAlloc( LPTR, bytesRequired );

			if( moduleArrayBytes && EnumProcessModules( process, (HMODULE *)moduleArrayBytes, bytesRequired, &bytesRequired ) )
			{
				moduleCount = bytesRequired / sizeof( HMODULE );
				moduleArray = (HMODULE *)moduleArrayBytes;
			}
		}
	}

	for( i = 0; i < moduleCount; i++ )
	{
		MODULEINFO info;
		GetModuleInformation( process, moduleArray[i], &info, sizeof(MODULEINFO) );

		if( ( address > info.lpBaseOfDll ) &&
			( (DWORD64)address < (DWORD64)info.lpBaseOfDll + (DWORD64)info.SizeOfImage ) )
			return GetModuleBaseName( process, moduleArray[i], name, len );
	}
	return Q_snprintf( name, len, "???" );
}

static void Sys_StackTrace( PEXCEPTION_POINTERS pInfo )
{
	char message[8192]; // match *nix Sys_Crash
	int len = 0;
	size_t i;
	HANDLE process = GetCurrentProcess();
	HANDLE thread = GetCurrentThread();
	IMAGEHLP_LINE64 line;
	DWORD dline = 0;
	DWORD options;
	CONTEXT context;
	STACKFRAME64 stackframe;
	DWORD image;

	context = *pInfo->ContextRecord;

	options = SymGetOptions();
	options |= SYMOPT_DEBUG;
	options |= SYMOPT_LOAD_LINES;
	SymSetOptions( options );

	SymInitialize( process, NULL, TRUE );

	ZeroMemory( &stackframe, sizeof( STACKFRAME64 ));

#ifdef _M_IX86
	image = IMAGE_FILE_MACHINE_I386;
	stackframe.AddrPC.Offset = context.Eip;
	stackframe.AddrPC.Mode = AddrModeFlat;
	stackframe.AddrFrame.Offset = context.Ebp;
	stackframe.AddrFrame.Mode = AddrModeFlat;
	stackframe.AddrStack.Offset = context.Esp;
	stackframe.AddrStack.Mode = AddrModeFlat;
#elif _M_X64
	image = IMAGE_FILE_MACHINE_AMD64;
	stackframe.AddrPC.Offset = context.Rip;
	stackframe.AddrPC.Mode = AddrModeFlat;
	stackframe.AddrFrame.Offset = context.Rsp;
	stackframe.AddrFrame.Mode = AddrModeFlat;
	stackframe.AddrStack.Offset = context.Rsp;
	stackframe.AddrStack.Mode = AddrModeFlat;
#elif _M_IA64
	image = IMAGE_FILE_MACHINE_IA64;
	stackframe.AddrPC.Offset = context.StIIP;
	stackframe.AddrPC.Mode = AddrModeFlat;
	stackframe.AddrFrame.Offset = context.IntSp;
	stackframe.AddrFrame.Mode = AddrModeFlat;
	stackframe.AddrBStore.Offset = context.RsBSP;
	stackframe.AddrBStore.Mode = AddrModeFlat;
	stackframe.AddrStack.Offset = context.IntSp;
	stackframe.AddrStack.Mode = AddrModeFlat;
#elif _M_ARM
	image = IMAGE_FILE_MACHINE_ARMNT;
	stackframe.AddrPC.Offset = context.Pc;
	stackframe.AddrPC.Mode = AddrModeFlat;
	stackframe.AddrFrame.Offset = context.R11;
	stackframe.AddrFrame.Mode = AddrModeFlat;
	stackframe.AddrStack.Offset = context.Sp;
	stackframe.AddrStack.Mode = AddrModeFlat;
#elif _M_ARM64
	image = IMAGE_FILE_MACHINE_ARM64;
	stackframe.AddrPC.Offset = context.Pc;
	stackframe.AddrPC.Mode = AddrModeFlat;
	stackframe.AddrFrame.Offset = context.Fp;
	stackframe.AddrFrame.Mode = AddrModeFlat;
	stackframe.AddrStack.Offset = context.Sp;
	stackframe.AddrStack.Mode = AddrModeFlat;
#elif
#error
#endif

	len = Q_snprintf( message, sizeof( message ), "Ver: " XASH_ENGINE_NAME " " XASH_VERSION " (build %i-%s, %s-%s)\n",
					  Q_buildnum(), g_buildcommit, Q_buildos(), Q_buildarch() );

	len += Q_snprintf( message + len, 1024 - len, "Sys_Crash: address %p, code %p\n",
					   pInfo->ExceptionRecord->ExceptionAddress, (void*)pInfo->ExceptionRecord->ExceptionCode );
	if( SymGetLineFromAddr64( process, (DWORD64)pInfo->ExceptionRecord->ExceptionAddress, &dline, &line ) )
	{
		len += Q_snprintf(message + len, 1024 - len, "Exception: %s:%d:%d\n",
						  (char*)line.FileName, (int)line.LineNumber, (int)dline);
	}
	if( SymGetLineFromAddr64( process, stackframe.AddrPC.Offset, &dline, &line ) )
	{
		len += Q_snprintf(message + len, 1024 - len,"PC: %s:%d:%d\n",
						  (char*)line.FileName, (int)line.LineNumber, (int)dline);
	}
	if( SymGetLineFromAddr64( process, stackframe.AddrFrame.Offset, &dline, &line ) )
	{
		len += Q_snprintf(message + len, 1024 - len,"Frame: %s:%d:%d\n",
						  (char*)line.FileName, (int)line.LineNumber, (int)dline);
	}
	for( i = 0; i < 25; i++ )
	{
		char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(TCHAR)];
		PSYMBOL_INFO symbol = (PSYMBOL_INFO)buffer;
		BOOL result = StackWalk64(
			image, process, thread,
			&stackframe, &context, NULL,
			SymFunctionTableAccess64, SymGetModuleBase64, NULL);
		DWORD64 displacement = 0;

		if( !result )
			break;

		symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
		symbol->MaxNameLen = MAX_SYM_NAME;

		len += Q_snprintf( message + len, 1024 - len, "% 2d %p",
						   i, (void*)stackframe.AddrPC.Offset );
		if( SymFromAddr( process, stackframe.AddrPC.Offset, &displacement, symbol ) )
		{
			len += Q_snprintf( message + len, 1024 - len, " %s ", symbol->Name );
		}
		if( SymGetLineFromAddr64( process, stackframe.AddrPC.Offset, &dline, &line ) )
		{
			len += Q_snprintf(message + len, 1024 - len,"(%s:%d:%d) ",
							  (char*)line.FileName, (int)line.LineNumber, (int)dline);
		}
		len += Q_snprintf( message + len, 1024 - len, "(");
		len += Sys_ModuleName( process, message + len, (void*)stackframe.AddrPC.Offset, 1024 - len );
		len += Q_snprintf( message + len, 1024 - len, ")\n");
	}

#if XASH_SDL == 2
	if( host.type != HOST_DEDICATED ) // let system to restart server automaticly
		SDL_ShowSimpleMessageBox( SDL_MESSAGEBOX_ERROR, "Sys_Crash", message, host.hWnd );
#endif

	Sys_PrintLog( message );

	SymCleanup( process );
}

static void Sys_GetProcessName( char *processName, size_t bufferSize )
{
	char fullpath[MAX_PATH];

	GetModuleBaseName( GetCurrentProcess(), NULL, fullpath, sizeof( fullpath ) - 1 );
	COM_FileBase( fullpath, processName, bufferSize );
}

static void Sys_GetMinidumpFileName( const char *processName, char *mdmpFileName, size_t bufferSize )
{
	time_t currentUtcTime = time( NULL );
	struct tm *currentLocalTime = localtime( &currentUtcTime );

	Q_snprintf( mdmpFileName, bufferSize, "%s_%s_crash_%d%.2d%.2d_%.2d%.2d%.2d.mdmp",
		processName,
		g_buildcommit,
		currentLocalTime->tm_year + 1900,
		currentLocalTime->tm_mon + 1,
		currentLocalTime->tm_mday,
		currentLocalTime->tm_hour,
		currentLocalTime->tm_min,
		currentLocalTime->tm_sec );
}

static qboolean Sys_WriteMinidump(PEXCEPTION_POINTERS exceptionInfo, MINIDUMP_TYPE minidumpType)
{
	HRESULT errorCode;
	string processName;
	string mdmpFileName;
	MINIDUMP_EXCEPTION_INFORMATION minidumpInfo;

	Sys_GetProcessName( processName, sizeof( processName ));
	Sys_GetMinidumpFileName( processName, mdmpFileName, sizeof( mdmpFileName ));

	SetLastError( NOERROR );
	HANDLE fileHandle = CreateFile(
		mdmpFileName, GENERIC_WRITE, FILE_SHARE_WRITE,
		NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);

	errorCode = HRESULT_FROM_WIN32( GetLastError( ));
	if( !SUCCEEDED( errorCode )) {
		CloseHandle( fileHandle );
		return false;
	}

	minidumpInfo.ThreadId = GetCurrentThreadId();
	minidumpInfo.ExceptionPointers = exceptionInfo;
	minidumpInfo.ClientPointers = FALSE;

	qboolean status = MiniDumpWriteDump(
		GetCurrentProcess(), GetCurrentProcessId(), fileHandle,
										minidumpType, &minidumpInfo, NULL, NULL);

	CloseHandle( fileHandle );
	return status;
}

#endif /* DBGHELP */

static LPTOP_LEVEL_EXCEPTION_FILTER  oldFilter;

static long _stdcall Sys_Crash( PEXCEPTION_POINTERS pInfo )
{
	// save config
	if( host.status != HOST_CRASHED )
	{
		// check to avoid recursive call
		host.crashed = true;

#if !XASH_DEDICATED
		IN_SetMouseGrab( false );
#endif // XASH_SDL

#if DBGHELP
		Sys_StackTrace( pInfo );
#else
		Sys_Warn( "Sys_Crash: call %p at address %p", pInfo->ExceptionRecord->ExceptionAddress, pInfo->ExceptionRecord->ExceptionCode );
#endif

		if( host.type == HOST_NORMAL )
			CL_Crashed(); // tell client about crash
			else host.status = HOST_CRASHED;

#if DBGHELP
			if( Sys_CheckParm( "-minidumps" ))
			{
				int minidumpFlags = (
					MiniDumpWithDataSegs |
					MiniDumpWithCodeSegs |
					MiniDumpWithHandleData |
					MiniDumpWithFullMemory |
					MiniDumpWithFullMemoryInfo |
					MiniDumpWithIndirectlyReferencedMemory |
					MiniDumpWithThreadInfo |
					MiniDumpWithModuleHeaders);

				if( !Sys_WriteMinidump( pInfo, (MINIDUMP_TYPE)minidumpFlags )) {
					// fallback method, create minidump with minimal info in it
					Sys_WriteMinidump( pInfo, MiniDumpWithDataSegs );
				}
			}
#endif

			if( host_developer.value <= 0 )
			{
				// no reason to call debugger in release build - just exit
				Sys_Quit( "crashed" );
				return EXCEPTION_CONTINUE_EXECUTION;
			}

			// all other states keep unchanged to let debugger find bug
			Sys_DestroyConsole();
	}

	if( oldFilter )
		return oldFilter( pInfo );
	return EXCEPTION_CONTINUE_EXECUTION;
}

void Sys_SetupCrashHandler( const char *argv0 )
{
	SetErrorMode( SEM_FAILCRITICALERRORS );	// no abort/retry/fail errors
	oldFilter = SetUnhandledExceptionFilter( Sys_Crash );
}

void Sys_RestoreCrashHandler( void )
{
	// restore filter
	if( oldFilter ) SetUnhandledExceptionFilter( oldFilter );
}