/**

 * vim: set ts=4 :

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

 * SourceMod

 * Copyright (C) 2004-2007 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 "sm_globals.h"

#include "PluginSys.h"

#include "ForwardSys.h"

#include "HandleSys.h"

HandleType_t g_GlobalFwdType = 0;

HandleType_t g_PrivateFwdType = 0;

static bool s_CallStarted = false;

static ICallable *s_pCallable = NULL;

static IPluginFunction *s_pFunction = NULL;

static IForward *s_pForward = NULL;

class ForwardNativeHelpers : 

	public SMGlobalClass,

	public IHandleTypeDispatch

{

public:

	void OnSourceModAllInitialized()

	{

		HandleAccess sec;

		/* Set GlobalFwd handle access security */

		g_HandleSys.InitAccessDefaults(NULL, &sec);

		sec.access[HandleAccess_Read] = 0;

		sec.access[HandleAccess_Clone] = HANDLE_RESTRICT_IDENTITY | HANDLE_RESTRICT_OWNER;

		/* Create 'GlobalFwd' handle type */

		g_GlobalFwdType = g_HandleSys.CreateType("GlobalFwd", this, 0, NULL, &sec, g_pCoreIdent, NULL);

		/* Private forwards are cloneable */

		sec.access[HandleAccess_Clone] = 0;

		/* Create 'PrivateFwd' handle type */

		g_PrivateFwdType = g_HandleSys.CreateType("PrivateFwd", this, g_GlobalFwdType, NULL, &sec, g_pCoreIdent, NULL);

	}

	void OnSourceModShutdown()

	{

		g_HandleSys.RemoveType(g_PrivateFwdType, g_pCoreIdent);

		g_HandleSys.RemoveType(g_GlobalFwdType, g_pCoreIdent);

	}

	void OnHandleDestroy(HandleType_t type, void *object)

	{

		IForward *pForward = static_cast<IForward *>(object);

		g_Forwards.ReleaseForward(pForward);

	}

} g_ForwardNativeHelpers;

/* Turn a public index into a function ID */

inline funcid_t PublicIndexToFuncId(uint32_t idx)

{

	return (idx << 1) | (1 << 0);

}

/* Reset global function/forward call variables */

inline void ResetCall()

{

	s_CallStarted = false;

	s_pFunction = NULL;

	s_pForward = NULL;

	s_pCallable = NULL;

}

static cell_t sm_GetFunctionByName(IPluginContext *pContext, const cell_t *params)

{

	Handle_t hndl = static_cast<Handle_t>(params[1]);

	HandleError err;

	char *name;

	uint32_t idx;

	IPlugin *pPlugin;

	if (hndl == 0)

	{

		pPlugin = g_PluginSys.FindPluginByContext(pContext->GetContext());

	} else {

		pPlugin = g_PluginSys.PluginFromHandle(hndl, &err);

		if (!pPlugin)

		{

			return pContext->ThrowNativeError("Plugin handle %x is invalid (error %d)", hndl, err);

		}

	}

	pContext->LocalToString(params[2], &name);

	/* Get public function index */

	if (pPlugin->GetBaseContext()->FindPublicByName(name, &idx) == SP_ERROR_NOT_FOUND)

	{

		/* Return INVALID_FUNCTION if not found */

		return -1;

	}

	/* Return function ID */

	return PublicIndexToFuncId(idx);

}

static cell_t sm_CreateGlobalForward(IPluginContext *pContext, const cell_t *params)

{

	cell_t count = params[0];

	char *name;

	ParamType forwardParams[SP_MAX_EXEC_PARAMS];

	if (count - 2 > SP_MAX_EXEC_PARAMS)

	{

		return pContext->ThrowNativeErrorEx(SP_ERROR_PARAMS_MAX, NULL);

	}

	pContext->LocalToString(params[1], &name);

	cell_t *addr;

	for (int i = 3; i <= count; i++)

	{

		pContext->LocalToPhysAddr(params[i], &addr);

		forwardParams[i - 3] = static_cast<ParamType>(*addr);

	}

	IForward *pForward = g_Forwards.CreateForward(name, static_cast<ExecType>(params[2]), count - 2, forwardParams);

	return g_HandleSys.CreateHandle(g_GlobalFwdType, pForward, pContext->GetIdentity(), g_pCoreIdent, NULL);

}

static cell_t sm_CreateForward(IPluginContext *pContext, const cell_t *params)

{

	cell_t count = params[0];

	ParamType forwardParams[SP_MAX_EXEC_PARAMS];

	if (count - 1 > SP_MAX_EXEC_PARAMS)

	{

		return pContext->ThrowNativeErrorEx(SP_ERROR_PARAMS_MAX, NULL);

	}

	cell_t *addr;

	for (int i = 2; i <= count; i++)

	{

		pContext->LocalToPhysAddr(params[i], &addr);

		forwardParams[i - 2] = static_cast<ParamType>(*addr);

	}

	IChangeableForward *pForward = g_Forwards.CreateForwardEx(NULL, static_cast<ExecType>(params[1]), count - 1, forwardParams);

	return g_HandleSys.CreateHandle(g_PrivateFwdType, pForward, pContext->GetIdentity(), g_pCoreIdent, NULL);

}

static cell_t sm_GetForwardFunctionCount(IPluginContext *pContext, const cell_t *params)

{

	Handle_t hndl = static_cast<Handle_t>(params[1]);

	HandleError err;

	IForward *pForward;

	if ((err=g_HandleSys.ReadHandle(hndl, g_GlobalFwdType, NULL, (void **)&pForward))

		!= HandleError_None)

	{

		return pContext->ThrowNativeError("Invalid forward handle %x (error %d)", hndl, err);

	}

	return pForward->GetFunctionCount();

}

static cell_t sm_AddToForward(IPluginContext *pContext, const cell_t *params)

{

	Handle_t fwdHandle = static_cast<Handle_t>(params[1]);

	Handle_t plHandle = static_cast<Handle_t>(params[2]);

	HandleError err;

	IChangeableForward *pForward;

	IPlugin *pPlugin;

	if ((err=g_HandleSys.ReadHandle(fwdHandle, g_PrivateFwdType, NULL, (void **)&pForward))

		!= HandleError_None)

	{

		return pContext->ThrowNativeError("Invalid private forward handle %x (error %d)", fwdHandle, err);

	}

	if (plHandle == 0)

	{

		pPlugin = g_PluginSys.FindPluginByContext(pContext->GetContext());

	} else {

		pPlugin = g_PluginSys.PluginFromHandle(plHandle, &err);

		if (!pPlugin)

		{

			return pContext->ThrowNativeError("Plugin handle %x is invalid (error %d)", plHandle, err);

		}

	}

	IPluginFunction *pFunction = pPlugin->GetBaseContext()->GetFunctionById(params[3]);

	if (!pFunction)

	{

		return pContext->ThrowNativeError("Invalid function id (%X)", params[3]);

	}

	return pForward->AddFunction(pFunction);

}

static cell_t sm_RemoveFromForward(IPluginContext *pContext, const cell_t *params)

{

	Handle_t fwdHandle = static_cast<Handle_t>(params[1]);

	Handle_t plHandle = static_cast<Handle_t>(params[2]);

	HandleError err;

	IChangeableForward *pForward;

	IPlugin *pPlugin;

	if ((err=g_HandleSys.ReadHandle(fwdHandle, g_PrivateFwdType, NULL, (void **)&pForward))

		!= HandleError_None)

	{

		return pContext->ThrowNativeError("Invalid private forward handle %x (error %d)", fwdHandle, err);

	}

	if (plHandle == 0)

	{

		pPlugin = g_PluginSys.FindPluginByContext(pContext->GetContext());

	} else {

		pPlugin = g_PluginSys.PluginFromHandle(plHandle, &err);

		if (!pPlugin)

		{

			return pContext->ThrowNativeError("Plugin handle %x is invalid (error %d)", plHandle, err);

		}

	}

	IPluginFunction *pFunction = pPlugin->GetBaseContext()->GetFunctionById(params[3]);

	if (!pFunction)

	{

		return pContext->ThrowNativeError("Invalid function id (%X)", params[3]);

	}

	return pForward->RemoveFunction(pFunction);

}

static cell_t sm_RemoveAllFromForward(IPluginContext *pContext, const cell_t *params)

{

	Handle_t fwdHandle = static_cast<Handle_t>(params[1]);

	Handle_t plHandle = static_cast<Handle_t>(params[2]);

	HandleError err;

	IChangeableForward *pForward;

	IPlugin *pPlugin;

	if ((err=g_HandleSys.ReadHandle(fwdHandle, g_PrivateFwdType, NULL, (void **)&pForward))

		!= HandleError_None)

	{

		return pContext->ThrowNativeError("Invalid private forward handle %x (error %d)", fwdHandle, err);

	}

	if (plHandle == 0)

	{

		pPlugin = g_PluginSys.FindPluginByContext(pContext->GetContext());

	} else {

		pPlugin = g_PluginSys.PluginFromHandle(plHandle, &err);

		if (!pPlugin)

		{

			return pContext->ThrowNativeError("Plugin handle %x is invalid (error %d)", plHandle, err);

		}

	}

	return pForward->RemoveFunctionsOfPlugin(pPlugin);

}

static cell_t sm_CallStartFunction(IPluginContext *pContext, const cell_t *params)

{

	Handle_t hndl;

	HandleError err;

	IPlugin *pPlugin;

	if (s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot start a call while one is already in progress");

	}

	hndl = static_cast<Handle_t>(params[1]);

	if (hndl == 0)

	{

		pPlugin = g_PluginSys.FindPluginByContext(pContext->GetContext());

	} else {

		pPlugin = g_PluginSys.PluginFromHandle(hndl, &err);

		if (!pPlugin)

		{

			return pContext->ThrowNativeError("Plugin handle %x is invalid (error %d)", hndl, err);

		}

	}

	s_pFunction = pPlugin->GetBaseContext()->GetFunctionById(params[2]);

	if (!s_pFunction)

	{

		return pContext->ThrowNativeError("Invalid function id (%X)", params[2]);

	}

	s_pCallable = static_cast<ICallable *>(s_pFunction);

	s_CallStarted = true;

	return 1;

}

static cell_t sm_CallStartForward(IPluginContext *pContext, const cell_t *params)

{

	Handle_t hndl;

	HandleError err;

	IForward *pForward;

	if (s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot start a call while one is already in progress");

	}

	hndl = static_cast<Handle_t>(params[1]);

	if ((err=g_HandleSys.ReadHandle(hndl, g_GlobalFwdType, NULL, (void **)&pForward))

		!= HandleError_None)

	{

		return pContext->ThrowNativeError("Invalid forward handle %x (error %d)", hndl, err);

	}

	s_pForward = pForward;

	s_pCallable = static_cast<ICallable *>(pForward);

	s_CallStarted = true;

	return 1;

}

static cell_t sm_CallPushCell(IPluginContext *pContext, const cell_t *params)

{

	int err;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	err = s_pCallable->PushCell(params[1]);

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushCellRef(IPluginContext *pContext, const cell_t *params)

{

	int err;

	cell_t *addr;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	pContext->LocalToPhysAddr(params[1], &addr);

	err = s_pCallable->PushCellByRef(addr);

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushFloat(IPluginContext *pContext, const cell_t *params)

{

	int err;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	err = s_pCallable->PushFloat(sp_ctof(params[1]));

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushFloatRef(IPluginContext *pContext, const cell_t *params)

{

	int err;

	cell_t *addr;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	pContext->LocalToPhysAddr(params[1], &addr);

	err = s_pCallable->PushFloatByRef(reinterpret_cast<float *>(addr));

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushArray(IPluginContext *pContext, const cell_t *params)

{

	int err;

	cell_t *addr;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	pContext->LocalToPhysAddr(params[1], &addr);

	err = s_pCallable->PushArray(addr, params[2]);

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushArrayEx(IPluginContext *pContext, const cell_t *params)

{

	int err;

	cell_t *addr;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	pContext->LocalToPhysAddr(params[1], &addr);

	err = s_pCallable->PushArray(addr, params[2], params[3]);

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushString(IPluginContext *pContext, const cell_t *params)

{

	int err;

	char *value;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	pContext->LocalToString(params[1], &value);

	err = s_pCallable->PushString(value);

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallPushStringEx(IPluginContext *pContext, const cell_t *params)

{

	int err;

	char *value;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot push parameters when there is no call in progress");

	}

	pContext->LocalToString(params[1], &value);

	err = s_pCallable->PushStringEx(value, params[2], params[3], params[4]);

	if (err)

	{

		s_pCallable->Cancel();

		ResetCall();

		return pContext->ThrowNativeErrorEx(err, NULL);

	}

	return 1;

}

static cell_t sm_CallFinish(IPluginContext *pContext, const cell_t *params)

{

	int err = SP_ERROR_NOT_RUNNABLE;

	cell_t *result;

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot finish call when there is no call in progress");

	}

	pContext->LocalToPhysAddr(params[1], &result);

	if (s_pFunction)

	{

		IPluginFunction *pFunction = s_pFunction;

		ResetCall();

		err = pFunction->Execute(result);

	} else if (s_pForward) {

		IForward *pForward = s_pForward;

		ResetCall();

		err = pForward->Execute(result, NULL);

	}

	return err;

}

static cell_t sm_CallCancel(IPluginContext *pContext, const cell_t *params)

{

	if (!s_CallStarted)

	{

		return pContext->ThrowNativeError("Cannot cancel call when there is no call in progress");

	}

	s_pCallable->Cancel();

	ResetCall();

	return 1;

}