/**

  * vim: set ts=4 :

  * =============================================================================

  * SourceMod SDKTools Extension

  * Copyright (C) 2004-2008 AlliedModders LLC.  All rights reserved.

  * =============================================================================

  *

  * This program is free software; you can redistribute it and/or modify it under

  * the terms of the GNU General Public License, version 3.0, as published by the

  * Free Software Foundation.

  * 

  * 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/>.

  *

  * As a special exception, AlliedModders LLC gives you permission to link the

  * code of this program (as well as its derivative works) to "Half-Life 2," the

  * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software

  * by the Valve Corporation.  You must obey the GNU General Public License in

  * all respects for all other code used.  Additionally, AlliedModders LLC grants

  * this exception to all derivative works.  AlliedModders LLC defines further

  * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),

  * or <http://www.sourcemod.net/license.php>.

  *

  * Version: $Id$

  */

 #include "extension.h"

 #include "output.h"

 ISourcePawnEngine *spengine = NULL;

 EntityOutputManager g_OutputManager;

 EntityOutputManager::EntityOutputManager()

 {

 	info_address = NULL;

 	info_callback = NULL;

 	HookCount = 0;

 	is_detoured = false;

 	enabled = false;

 }

 EntityOutputManager::~EntityOutputManager()

 {

 	if (!enabled)

 	{

 		return;

 	}

 	EntityOutputs->Destroy();

 	ClassNames->Destroy();

 	ShutdownFireEventDetour();

 }

 void EntityOutputManager::Init()

 {

 	enabled = CreateFireEventDetour();

 	if (!enabled)

 	{

 		return;

 	}

 	EntityOutputs = adtfactory->CreateBasicTrie();

 	ClassNames = adtfactory->CreateBasicTrie();

 }

 bool EntityOutputManager::IsEnabled()

 {

 	return enabled;

 }

 bool EntityOutputManager::CreateFireEventDetour()

 {

 	if (!g_pGameConf->GetMemSig("FireOutput", &info_address) || !info_address)

 	{

 		g_pSM->LogError(myself, "Could not locate FireOutput - Disabling Entity Outputs");

 		return false;

 	}

 	if (!g_pGameConf->GetOffset("FireOutputBackup", (int *)&(info_restore.bytes)))

 	{

 		g_pSM->LogError(myself, "Could not locate FireOutputBackup - Disabling Entity Outputs");

 		return false;

 	}

 	/* First, save restore bits */

 	for (size_t i=0; i<info_restore.bytes; i++)

 	{

 		info_restore.patch[i] = ((unsigned char *)info_address)[i];

 	}

 	info_callback = spengine->ExecAlloc(100);

 	JitWriter wr;

 	JitWriter *jit = ≀

 	wr.outbase = (jitcode_t)info_callback;

 	wr.outptr = wr.outbase;

 	/* Function we are detouring into is

 	 *

 	 * void FireEventDetour(CBaseEntityOutput(void *) *pOutput, CBaseEntity *pActivator, CBaseEntity *pCaller, float fDelay = 0 )

 	 */

 	/* push		fDelay [esp+20h]

 	 * push		pCaller [esp+1Ch]

 	 * push		pActivator [esp+18h]

 	 * push		pOutput [ecx]

 	 */

 #if defined PLATFORM_WINDOWS

 	IA32_Push_Rm_Disp8_ESP(jit, 32);

 	IA32_Push_Rm_Disp8_ESP(jit, 32);

 	IA32_Push_Rm_Disp8_ESP(jit, 32);

 	IA32_Push_Reg(jit, REG_ECX);

 #elif defined PLATFORM_LINUX

 	IA32_Push_Rm_Disp8_ESP(jit, 20);

 	IA32_Push_Rm_Disp8_ESP(jit, 20);

 	IA32_Push_Rm_Disp8_ESP(jit, 20);

 	IA32_Push_Rm_Disp8_ESP(jit, 16);

 #endif

 	jitoffs_t call = IA32_Call_Imm32(jit, 0); 

 	IA32_Write_Jump32_Abs(jit, call, (void *)TempDetour);

 #if defined PLATFORM_LINUX

 	IA32_Add_Rm_Imm8(jit, REG_ESP, 4, MOD_REG);		//add esp, 4

 #elif defined PLATFORM_WINDOWS

 	IA32_Pop_Reg(jit, REG_ECX);

 #endif

 	IA32_Add_Rm_Imm8(jit, REG_ESP, 12, MOD_REG);	//add esp, 12 (0Ch)

 	/* Patch old bytes in */

 	for (size_t i=0; i<info_restore.bytes; i++)

 	{

 		jit->write_ubyte(info_restore.patch[i]);

 	}

 	/* Return to the original function */

 	call = IA32_Jump_Imm32(jit, 0);

 	IA32_Write_Jump32_Abs(jit, call, (unsigned char *)info_address + info_restore.bytes);

 	return true;

 }

 void EntityOutputManager::InitFireEventDetour()

 {

 	if (!is_detoured)

 	{

 		DoGatePatch((unsigned char *)info_address, &info_callback);

 		is_detoured = true;

 	}

 }

 void EntityOutputManager::DeleteFireEventDetour()

 {

 	if (is_detoured)

 	{

 		ShutdownFireEventDetour();

 	}

 	if (info_callback)

 	{

 		/* Free the gate */

 		spengine->ExecFree(info_callback);

 		info_callback = NULL;

 	}

 }

 void TempDetour(void *pOutput, CBaseEntity *pActivator, CBaseEntity *pCaller, float fDelay)

 {

 	g_OutputManager.FireEventDetour(pOutput, pActivator, pCaller, fDelay);

 }

 void EntityOutputManager::ShutdownFireEventDetour()

 {

 	if (info_callback)

 	{

 		/* Remove the patch */

 		ApplyPatch(info_address, 0, &info_restore, NULL);

 		is_detoured = false;

 	}

 }

 void EntityOutputManager::FireEventDetour(void *pOutput, CBaseEntity *pActivator, CBaseEntity *pCaller, float fDelay)

 {

 	char sOutput[20];

 	Q_snprintf(sOutput, sizeof(sOutput), "%x", pOutput);

 	// attempt to directly lookup a hook using the pOutput pointer

 	OutputNameStruct *pOutputName = NULL;

 	edict_t *pEdict = gameents->BaseEntityToEdict(pCaller);

 	/* TODO: Add support for entities without an edict */

 	if (pEdict == NULL)

 	{

 		return;

 	}

 	bool fastLookup = false;

 	// Fast lookup failed - check the slow way for hooks that havn't fired yet

 	if ((fastLookup = EntityOutputs->Retrieve(sOutput, (void **)&pOutputName)) == false)

 	{

 		const char *classname = pEdict->GetClassName();

 		const char *outputname = FindOutputName(pOutput, pCaller);

 		pOutputName = FindOutputPointer(classname, outputname, false);

 		if (!pOutputName)

 		{

 			return;

 		}

 	}

 	if (!pOutputName->hooks.empty())

 	{

 		if (!fastLookup)

 		{

 			// hook exists on this classname and output - map it into our quick find trie

 			EntityOutputs->Insert(sOutput, pOutputName);

 		}

 		SourceHook::List<omg_hooks *>::iterator _iter;

 		omg_hooks *hook;

 		_iter = pOutputName->hooks.begin();

 		while (_iter != pOutputName->hooks.end())

 		{

 			hook = (omg_hooks *)*_iter;

 			hook->in_use = true;

 			int serial = pEdict->m_NetworkSerialNumber;

 			if (serial != hook->entity_filter && hook->entity_index == engine->IndexOfEdict(pEdict))

 			{

 				// same entity index but different serial number. Entity has changed, kill the hook.

 				_iter = pOutputName->hooks.erase(_iter);

 				CleanUpHook(hook);

 				continue;

 			}

 			if (hook->entity_filter == -1 || hook->entity_filter == serial) // Global classname hook

 			{

 				//fire the forward to hook->pf

 				hook->pf->PushString(pOutputName->Name);

 				hook->pf->PushCell(engine->IndexOfEdict(pEdict));

 				edict_t *pEdictActivator = gameents->BaseEntityToEdict(pActivator);

 				if (!pEdictActivator)

 				{

 					hook->pf->PushCell(-1);

 				}

 				else

 				{

 					hook->pf->PushCell(engine->IndexOfEdict(pEdictActivator));

 				}

 				//hook->pf->PushCell(handle);

 				hook->pf->PushFloat(fDelay);

 				hook->pf->Execute(NULL);

 				if ((hook->entity_filter != -1) && hook->only_once)

 				{

 					_iter = pOutputName->hooks.erase(_iter);

 					CleanUpHook(hook);

 					continue;

 				}

 				if (hook->delete_me)

 				{

 					_iter = pOutputName->hooks.erase(_iter);

 					CleanUpHook(hook);

 					continue;

 				}

 			}

 			hook->in_use = false;

 			_iter++;

 		}

 	}

 }

 omg_hooks *EntityOutputManager::NewHook()

 {

 	omg_hooks *hook;

 	if (FreeHooks.empty())

 	{

 		hook = new omg_hooks;

 	}

 	else

 	{

 		hook = g_OutputManager.FreeHooks.front();

 		g_OutputManager.FreeHooks.pop();

 	}

 	return hook;

 }

 void EntityOutputManager::OnHookAdded()

 {

 	HookCount++;

 	if (HookCount == 1)

 	{

 		// This is the first hook created

 		InitFireEventDetour();

 	}

 }

 void EntityOutputManager::OnHookRemoved()

 {

 	HookCount--;

 	if (HookCount == 0)

 	{

 		ShutdownFireEventDetour();

 	}

 }

 void EntityOutputManager::CleanUpHook(omg_hooks *hook)

 {

 	FreeHooks.push(hook);

 	OnHookRemoved();

 	IPlugin *pPlugin = plsys->FindPluginByContext(hook->pf->GetParentContext()->GetContext());

 	SourceHook::List<omg_hooks *> *pList = NULL;

 	if (!pPlugin->GetProperty("OutputHookList", (void **)&pList, false) || !pList)

 	{

 		return;

 	}

 	SourceHook::List<omg_hooks *>::iterator p_iter = pList->begin();

 	omg_hooks *pluginHook;

 	while (p_iter != pList->end())

 	{

 		pluginHook = (omg_hooks *)*p_iter;

 		if (pluginHook == hook)

 		{

 			p_iter = pList->erase(p_iter);

 		}

 		else

 		{

 			p_iter++;

 		}

 	}

 }

 void EntityOutputManager::OnPluginDestroyed(IPlugin *plugin)

 {

 	SourceHook::List<omg_hooks *> *pList = NULL;

 	if (plugin->GetProperty("OutputHookList", (void **)&pList, true))

 	{

 		SourceHook::List<omg_hooks *>::iterator p_iter = pList->begin();

 		omg_hooks *hook;

 		while (p_iter != pList->end())

 		{

 			hook = (omg_hooks *)*p_iter;

 			p_iter = pList->erase(p_iter); //remove from this plugins list

 			hook->m_parent->hooks.remove(hook); // remove from the y's list

 			FreeHooks.push(hook); //save the omg_hook

 			OnHookRemoved();

 		}		

 	}

 }

 OutputNameStruct *EntityOutputManager::FindOutputPointer(const char *classname, const char *outputname, bool create)

 {

 	ClassNameStruct *pClassname;

 	if (!ClassNames->Retrieve(classname, (void **)&pClassname))

 	{

 		if (create)

 		{

 			pClassname = new ClassNameStruct;

 			ClassNames->Insert(classname, pClassname);

 		}

 		else

 		{

 			return NULL;

 		}

 	}

 	OutputNameStruct *pOutputName;

 	if (!pClassname->OutputList->Retrieve(outputname, (void **)&pOutputName))

 	{

 		if (create)

 		{

 			pOutputName = new OutputNameStruct;

 			pClassname->OutputList->Insert(outputname, pOutputName);

 			strncpy(pOutputName->Name, outputname, sizeof(pOutputName->Name));

 			pOutputName->Name[49] = 0;

 		}

 		else

 		{

 			return NULL;

 		}

 	}

 	return pOutputName;

 }

 // Iterate the datamap of pCaller and look for output pointers with the same address as pOutput

 const char *EntityOutputManager::FindOutputName(void *pOutput, CBaseEntity *pCaller)

 {

 	datamap_t *pMap = gamehelpers->GetDataMap(pCaller);

 	while (pMap)

 	{

 		for (int i=0; i<pMap->dataNumFields; i++)

 		{

 			if (pMap->dataDesc[i].flags & FTYPEDESC_OUTPUT)

 			{

 				if ((char *)pCaller + pMap->dataDesc[i].fieldOffset[0] == pOutput)

 				{

 					return pMap->dataDesc[i].externalName;

 				}

 			}

 		}

 		pMap = pMap->baseMap;

 	}

 	return NULL;

 }

 // Thanks SM core

 edict_t *EntityOutputManager::BaseHandleToEdict(CBaseHandle &hndl)

 {

 	if (!hndl.IsValid())

 	{

 		return NULL;

 	}

 	int index = hndl.GetEntryIndex();

 	edict_t *pStoredEdict;

 	pStoredEdict = engine->PEntityOfEntIndex(index);

 	if (pStoredEdict == NULL)

 	{

 		return NULL;

 	}

 	IServerEntity *pSE = pStoredEdict->GetIServerEntity();

 	if (pSE == NULL)

 	{

 		return NULL;

 	}

 	if (pSE->GetRefEHandle() != hndl)

 	{

 		return NULL;

 	}

 	return pStoredEdict;

 }