qzdoom/src/scripting/decorate/thingdef_parse.cpp

/*
** thingdef-parse.cpp
**
** Actor definitions - all parser related code
**
**---------------------------------------------------------------------------
** Copyright 2002-2007 Christoph Oelckers
** Copyright 2004-2007 Randy Heit
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
**    notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
**    notice, this list of conditions and the following disclaimer in the
**    documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
**    derived from this software without specific prior written permission.
** 4. When not used as part of ZDoom or a ZDoom derivative, this code will be
**    covered by the terms of the GNU General Public License as published by
**    the Free Software Foundation; either version 2 of the License, or (at
**    your option) any later version.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
*/

#include "doomtype.h"
#include "actor.h"
#include "a_pickups.h"
#include "sc_man.h"
#include "thingdef.h"
#include "a_morph.h"
#include "cmdlib.h"
#include "templates.h"
#include "v_palette.h"
#include "doomerrors.h"
#include "i_system.h"
#include "codegeneration/codegen.h"
#include "w_wad.h"
#include "v_video.h"
#include "version.h"
#include "v_text.h"
#include "m_argv.h"

void ParseOldDecoration(FScanner &sc, EDefinitionType def);
EXTERN_CVAR(Bool, strictdecorate);


//==========================================================================
//
// DecoDerivedClass
//
// Create a derived class and performs some additional sanity checks
//
//==========================================================================

PClassActor *DecoDerivedClass(const FScriptPosition &sc, PClassActor *parent, FName typeName)
{
	PClassActor *type = static_cast<PClassActor *>(parent->CreateDerivedClass(typeName, parent->Size));
	if (type == nullptr)
	{
		FString newname = typeName.GetChars();
		FString sourcefile = sc.FileName;

		sourcefile.Substitute(":", "@");
		newname << '@' << sourcefile;
		if (strictdecorate)
		{
			sc.Message(MSG_ERROR, "Tried to define class '%s' more than once.", typeName.GetChars());
		}
		else
		{
			// Due to backwards compatibility issues this cannot be an unconditional error.
			sc.Message(MSG_WARNING, "Tried to define class '%s' more than once. Renaming class to '%s'", typeName.GetChars(), newname.GetChars());
		}
		type = static_cast<PClassActor *>(parent->CreateDerivedClass(newname, parent->Size));
		if (type == nullptr)
		{
			// This we cannot handle cleanly anymore. Let's just abort and forget about the odd mod out that was this careless.
			sc.Message(MSG_FATAL, "Tried to define class '%s' more than twice in the same file.", typeName.GetChars());
		}
	}
	return type;
}

//==========================================================================
//
// ParseParameter
//
// Parses a parameter - either a default in a function declaration 
// or an argument in a function call.
//
//==========================================================================

FxExpression *ParseParameter(FScanner &sc, PClassActor *cls, PType *type, bool constant)
{
	FxExpression *x = NULL;
	int v;

	if (type == TypeSound)
	{
		sc.MustGetString();
		x = new FxConstant(FSoundID(sc.String), sc);
	}
	else if (type == TypeBool || type == TypeSInt32 || type == TypeFloat64)
	{
		x = ParseExpression (sc, cls, constant);
		if (constant && !x->isConstant())
		{
			sc.ScriptMessage("Default parameter must be constant.");
			FScriptPosition::ErrorCounter++;
		}
		// Do automatic coercion between bools, ints and floats.
		if (type == TypeBool)
		{
			x = new FxBoolCast(x);
		}
		else if (type == TypeSInt32)
		{
			x = new FxIntCast(x);
		}
		else
		{
			x = new FxFloatCast(x);
		}
	}
	else if (type == TypeName || type == TypeString)
	{
		sc.SetEscape(true);
		sc.MustGetString();
		sc.SetEscape(false);
		if (type == TypeName)
		{
			x = new FxConstant(sc.String[0] ? FName(sc.String) : NAME_None, sc);
		}
		else
		{
			x = new FxConstant(strbin1(sc.String), sc);
		}
	}
	else if (type == TypeColor)
	{
		sc.MustGetString ();
		if (sc.Compare("none"))
		{
			v = -1;
		}
		else if (sc.Compare(""))
		{
			v = 0;
		}
		else
		{
			int c = V_GetColor (NULL, sc.String);
			// 0 needs to be the default so we have to mark the color.
			v = MAKEARGB(1, RPART(c), GPART(c), BPART(c));
		}
		ExpVal val;
		val.Type = TypeColor;
		val.Int = v;
		x = new FxConstant(val, sc);
	}
	else if (type == TypeState)
	{
		// This forces quotation marks around the state name.
		if (sc.CheckToken(TK_StringConst))
		{
			if (sc.String[0] == 0 || sc.Compare("None"))
			{
				x = new FxConstant((FState*)NULL, sc);
			}
			else if (sc.Compare("*"))
			{
				if (constant)
				{
					x = new FxConstant((FState*)(intptr_t)-1, sc);
				}
				else sc.ScriptError("Invalid state name '*'");
			}
			else
			{
				x = new FxMultiNameState(sc.String, sc);
			}
		}
		else if (!constant)
		{
			x = new FxRuntimeStateIndex(ParseExpression(sc, cls));
		}
		else sc.MustGetToken(TK_StringConst); // This is for the error.
	}
	else if (type->GetClass() == RUNTIME_CLASS(PClassPointer))
	{	// Actor name
		sc.SetEscape(true);
		sc.MustGetString();
		sc.SetEscape(false);
		x = new FxClassTypeCast(static_cast<PClassPointer *>(type)->ClassRestriction, new FxConstant(FName(sc.String), sc));
	}
	else
	{
		assert(false && "Unknown parameter type");
		x = NULL;
	}
	return x;
}

//==========================================================================
//
// ActorConstDef
//
// Parses a constant definition.
//
//==========================================================================

static void ParseConstant (FScanner &sc, PSymbolTable *symt, PClassActor *cls)
{
	// Read the type and make sure it's int or float.
	if (sc.CheckToken(TK_Int) || sc.CheckToken(TK_Float))
	{
		int type = sc.TokenType;
		sc.MustGetToken(TK_Identifier);
		FName symname = sc.String;
		sc.MustGetToken('=');
		FxExpression *expr = ParseExpression (sc, cls, true);
		sc.MustGetToken(';');

		if (expr == nullptr)
		{
			sc.ScriptMessage("Error while resolving constant definition");
			FScriptPosition::ErrorCounter++;
		}
		else if (!expr->isConstant())
		{
			sc.ScriptMessage("Constant definition is not a constant");
			FScriptPosition::ErrorCounter++;
		}
		else
		{
			ExpVal val = static_cast<FxConstant *>(expr)->GetValue();
			delete expr;
			PSymbolConstNumeric *sym;
			if (type == TK_Int)
			{
				sym = new PSymbolConstNumeric(symname, TypeSInt32);
				sym->Value = val.GetInt();
			}
			else
			{
				sym = new PSymbolConstNumeric(symname, TypeFloat64);
				sym->Float = val.GetFloat();
			}
			if (symt->AddSymbol (sym) == NULL)
			{
				delete sym;
				sc.ScriptMessage ("'%s' is already defined in '%s'.",
					symname.GetChars(), cls? cls->TypeName.GetChars() : "Global");
				FScriptPosition::ErrorCounter++;
			}
		}
	}
	else
	{
		sc.ScriptMessage("Numeric type required for constant");
		FScriptPosition::ErrorCounter++;
	}
}

//==========================================================================
//
// ActorEnumDef
//
// Parses an enum definition.
//
//==========================================================================

static void ParseEnum (FScanner &sc, PSymbolTable *symt, PClassActor *cls)
{
	int currvalue = 0;

	sc.MustGetToken('{');
	while (!sc.CheckToken('}'))
	{
		sc.MustGetToken(TK_Identifier);
		FName symname = sc.String;
		if (sc.CheckToken('='))
		{
			FxExpression *expr = ParseExpression (sc, cls, true);
			if (expr != nullptr)
			{
				if (!expr->isConstant())
				{
					sc.ScriptMessage("'%s' must be constant", symname.GetChars());
					FScriptPosition::ErrorCounter++;
				}
				else
				{
					currvalue = static_cast<FxConstant *>(expr)->GetValue().GetInt();
				}
				delete expr;
			}
			else
			{
				sc.ScriptMessage("Error while resolving expression of '%s'", symname.GetChars());
				FScriptPosition::ErrorCounter++;
			}
		}
		PSymbolConstNumeric *sym = new PSymbolConstNumeric(symname, TypeSInt32);
		sym->Value = currvalue;
		if (symt->AddSymbol (sym) == NULL)
		{
			delete sym;
			sc.ScriptMessage ("'%s' is already defined in '%s'.",
				symname.GetChars(), cls? cls->TypeName.GetChars() : "Global");
			FScriptPosition::ErrorCounter++;
		}
		// This allows a comma after the last value but doesn't enforce it.
		if (sc.CheckToken('}')) break;
		sc.MustGetToken(',');
		currvalue++;
	}
	sc.MustGetToken(';');
}

//==========================================================================
//
// ParseArgListDef
//
// Parses the argument list from a function declaration.
//
//==========================================================================

static void ParseArgListDef(FScanner &sc, PClassActor *cls,
	TArray<PType *> &args, TArray<DWORD> &argflags)
{
	if (!sc.CheckToken(')'))
	{
		while (sc.TokenType != ')')
		{
			int flags = 0;
			PType *type = NULL;
			PClass *restrict = NULL;

			// Retrieve flags before type name
			for (;;)
			{
				if (sc.CheckToken(TK_Coerce) || sc.CheckToken(TK_Native))
				{
				}
				else
				{
					break;
				}
			}
			// Read the variable type
			sc.MustGetAnyToken();
			switch (sc.TokenType)
			{
			case TK_Bool:
				type = TypeBool;
				break;

			case TK_Int:
				type = TypeSInt32;
				break;

			case TK_Float:
				type = TypeFloat64;
				break;

			case TK_Sound:		type = TypeSound;		break;
			case TK_String:		type = TypeString;		break;
			case TK_Name:		type = TypeName;		break;
			case TK_State:		type = TypeState;		break;
			case TK_Color:		type = TypeColor;		break;
			case TK_Class:
				sc.MustGetToken('<');
				sc.MustGetToken(TK_Identifier);	// Get class name
				restrict = PClass::FindClass(sc.String);
				if (restrict == NULL)
				{
					sc.ScriptMessage("Unknown class type %s", sc.String);
					FScriptPosition::ErrorCounter++;
				}
				else
				{
					type = NewClassPointer(restrict);
				}
				sc.MustGetToken('>');
				break;
			case TK_Ellipsis:
				// Making the final type NULL signals a varargs function.
				type = NULL;
				sc.MustGetToken(')');
				sc.UnGet();
				break;
			default:
				sc.ScriptMessage ("Unknown variable type %s", sc.TokenName(sc.TokenType, sc.String).GetChars());
				type = TypeSInt32;
				FScriptPosition::ErrorCounter++;
				break;
			}
			// Read the optional variable name
			if (!sc.CheckToken(',') && !sc.CheckToken(')'))
			{
				sc.MustGetToken(TK_Identifier);
			}
			else
			{
				sc.UnGet();
			}

			if (sc.CheckToken('='))
			{
				flags |= VARF_Optional;
				FxExpression *def = ParseParameter(sc, cls, type, true);
				delete def;
			}

			args.Push(type);
			argflags.Push(flags);
			sc.MustGetAnyToken();
			if (sc.TokenType != ',' && sc.TokenType != ')')
			{
				sc.ScriptError ("Expected ',' or ')' but got %s instead", sc.TokenName(sc.TokenType, sc.String).GetChars());
			}
		}
	}
	sc.MustGetToken(';');
}

//==========================================================================
//
// ParseFunctionDef
//
// Parses a native function's parameters and adds it to the class,
// if possible.
//
//==========================================================================

void ParseFunctionDef(FScanner &sc, PClassActor *cls, FName funcname,
	TArray<PType *> &rets, DWORD funcflags)
{
	assert(cls != NULL);

	const AFuncDesc *afd;
	TArray<PType *> args;
	TArray<DWORD> argflags;
	TArray<FName> argnames;

	afd = FindFunction(funcname);
	if (afd == NULL)
	{
		sc.ScriptMessage ("The function '%s' has not been exported from the executable.", funcname.GetChars());
		FScriptPosition::ErrorCounter++;
	}
	sc.MustGetToken('(');

	SetImplicitArgs(&args, &argflags, &argnames, cls, funcflags);
	// This function will be removed once all internal classes have been ported so don't bother filling in the function's argument names, because for anything going through here they'll never be used.
	ParseArgListDef(sc, cls, args, argflags);

	if (afd != NULL)
	{
		PFunction *sym = new PFunction(funcname);
		sym->AddVariant(NewPrototype(rets, args), argflags, argnames, *(afd->VMPointer));
		sym->Flags = funcflags;
		if (cls->Symbols.AddSymbol(sym) == NULL)
		{
			delete sym;
			sc.ScriptMessage ("'%s' is already defined in class '%s'.",
				funcname.GetChars(), cls->TypeName.GetChars());
			FScriptPosition::ErrorCounter++;
		}
	}
}

//==========================================================================
//
// ParseNativeFunction
//
// Parses a non-action function declaration.
//
//==========================================================================

static void ParseNativeFunction(FScanner &sc, PClassActor *cls)
{
	TArray<PType *> rets(1);

	if (sc.LumpNum == -1 || Wads.GetLumpFile(sc.LumpNum) > 0)
	{
		sc.ScriptMessage ("functions can only be declared by native actors!");
		FScriptPosition::ErrorCounter++;
	}

	// Read the type and make sure it's acceptable.
	sc.MustGetAnyToken();
	switch (sc.TokenType)
	{
	case TK_Bool:
		rets.Push(TypeBool);
		break;

	case TK_Int:
		rets.Push(TypeSInt32);
		break;

	case TK_Float:
		rets.Push(TypeFloat64);
		break;

	case TK_State:
		rets.Push(TypeState);
		break;

	case TK_Void:
		break;

	case TK_Identifier:
		rets.Push(NewPointer(RUNTIME_CLASS(DObject)));
		// Todo: Object type
		sc.ScriptError("Object type variables not implemented yet!");
		break;

	default:
		sc.ScriptError("Invalid return type %s", sc.String);
		return;
	}
	sc.MustGetToken(TK_Identifier);
	ParseFunctionDef(sc, cls, sc.String, rets, VARF_Method);
}

//==========================================================================
//
// ParseUserVariable
//
// Parses a user variable declaration.
//
//==========================================================================

static void ParseUserVariable (FScanner &sc, PSymbolTable *symt, PClassActor *cls)
{
	PType *type;
	int maxelems = 1;

	// Only non-native classes may have user variables.
	if (!cls->bRuntimeClass)
	{
		sc.ScriptError("Native classes may not have user variables");
	}

	// Read the type and make sure it's acceptable.
	sc.MustGetAnyToken();
	if (sc.TokenType != TK_Int && sc.TokenType != TK_Float)
	{
		sc.ScriptMessage("User variables must be of type 'int' or 'float'");
		FScriptPosition::ErrorCounter++;
	}
	type = sc.TokenType == TK_Int ? (PType *)TypeSInt32 : (PType *)TypeFloat64;

	sc.MustGetToken(TK_Identifier);
	// For now, restrict user variables to those that begin with "user_" to guarantee
	// no clashes with internal member variable names.
	if (sc.StringLen < 6 || strnicmp("user_", sc.String, 5) != 0)
	{
		sc.ScriptMessage("User variable names must begin with \"user_\"");
		FScriptPosition::ErrorCounter++;
	}

	FName symname = sc.String;

	// We must ensure that we do not define duplicates, even when they come from a parent table.
	if (symt->FindSymbol(symname, true) != NULL)
	{
		sc.ScriptMessage ("'%s' is already defined in '%s' or one of its ancestors.",
			symname.GetChars(), cls ? cls->TypeName.GetChars() : "Global");
		FScriptPosition::ErrorCounter++;
		return;
	}

	if (sc.CheckToken('['))
	{
		FxExpression *expr = ParseExpression(sc, cls, true);
		if (expr == nullptr)
		{
			sc.ScriptMessage("Error while resolving array size");
			FScriptPosition::ErrorCounter++;
			maxelems = 1;
		}
		else if (!expr->isConstant())
		{
			sc.ScriptMessage("Array size must be a constant");
			FScriptPosition::ErrorCounter++;
			maxelems = 1;
		}
		else
		{
			maxelems = static_cast<FxConstant *>(expr)->GetValue().GetInt();
		}
		sc.MustGetToken(']');
		if (maxelems <= 0)
		{
			sc.ScriptMessage("Array size must be positive");
			FScriptPosition::ErrorCounter++;
			maxelems = 1;
		}
		type = NewArray(type, maxelems);
	}
	sc.MustGetToken(';');

	PField *sym = cls->AddField(symname, type, 0);
	if (sym == NULL)
	{
		sc.ScriptMessage ("'%s' is already defined in '%s'.",
			symname.GetChars(), cls ? cls->TypeName.GetChars() : "Global");
		FScriptPosition::ErrorCounter++;
	}
}

//==========================================================================
//
// Parses a flag name
//
//==========================================================================
static void ParseActorFlag (FScanner &sc, Baggage &bag, int mod)
{
	sc.MustGetString ();

	FString part1 = sc.String;
	const char *part2 = NULL;
	if (sc.CheckString ("."))
	{
		sc.MustGetString ();
		part2 = sc.String;
	}
	HandleActorFlag(sc, bag, part1, part2, mod);
}

//==========================================================================
//
// Processes a flag. Also used by olddecorations.cpp
//
//==========================================================================
void HandleActorFlag(FScanner &sc, Baggage &bag, const char *part1, const char *part2, int mod)
{
	FFlagDef *fd;

	if ( (fd = FindFlag (bag.Info, part1, part2)) )
	{
		AActor *defaults = (AActor*)bag.Info->Defaults;
		if (fd->structoffset == -1)	// this is a deprecated flag that has been changed into a real property
		{
			HandleDeprecatedFlags(defaults, bag.Info, mod=='+', fd->flagbit);
		}
		else
		{
			ModActorFlag(defaults, fd, mod == '+');
		}
	}
	else
	{
		if (part2 == NULL)
		{
			sc.ScriptMessage("\"%s\" is an unknown flag\n", part1);
		}
		else
		{
			sc.ScriptMessage("\"%s.%s\" is an unknown flag\n", part1, part2);
		}
		FScriptPosition::ErrorCounter++;
	}
}

//==========================================================================
//
// [MH] parses a morph style expression
//
//==========================================================================

struct FParseValue
{
	const char *Name;
	int Flag;
};

int ParseFlagExpressionString(FScanner &sc, const FParseValue *vals)
{
	// May be given flags by number...
	if (sc.CheckNumber())
	{
		sc.MustGetNumber();
		return sc.Number;
	}

	// ... else should be flags by name.
	// NOTE: Later this should be removed and a normal expression used.
	// The current DECORATE parser can't handle this though.
	bool gotparen = sc.CheckString("(");
	int style = 0;
	do
	{
		sc.MustGetString();
		style |= vals[sc.MustMatchString(&vals->Name, sizeof (*vals))].Flag;
	}
	while (sc.CheckString("|"));
	if (gotparen)
	{
		sc.MustGetStringName(")");
	}

	return style;
}



static int ParseMorphStyle (FScanner &sc)
{
 	static const FParseValue morphstyles[]={
		{ "MRF_ADDSTAMINA",			MORPH_ADDSTAMINA},
		{ "MRF_FULLHEALTH",			MORPH_FULLHEALTH}, 
		{ "MRF_UNDOBYTOMEOFPOWER",	MORPH_UNDOBYTOMEOFPOWER},  
		{ "MRF_UNDOBYCHAOSDEVICE",	MORPH_UNDOBYCHAOSDEVICE},
		{ "MRF_FAILNOTELEFRAG",		MORPH_FAILNOTELEFRAG}, 
		{ "MRF_FAILNOLAUGH",		MORPH_FAILNOLAUGH}, 
		{ "MRF_WHENINVULNERABLE",	MORPH_WHENINVULNERABLE}, 
		{ "MRF_LOSEACTUALWEAPON",	MORPH_LOSEACTUALWEAPON},
		{ "MRF_NEWTIDBEHAVIOUR",	MORPH_NEWTIDBEHAVIOUR}, 
		{ "MRF_UNDOBYDEATH",		MORPH_UNDOBYDEATH}, 
		{ "MRF_UNDOBYDEATHFORCED",	MORPH_UNDOBYDEATHFORCED},  
		{ "MRF_UNDOBYDEATHSAVES",	MORPH_UNDOBYDEATHSAVES},
		{ "MRF_UNDOALWAYS",			MORPH_UNDOALWAYS },
		{ "MRF_TRANSFERTRANSLATION", MORPH_TRANSFERTRANSLATION },
		{ NULL, 0 }
	};

	return ParseFlagExpressionString(sc, morphstyles);
}

static int ParseThingActivation (FScanner &sc)
{
 	static const FParseValue activationstyles[]={

		{ "THINGSPEC_Default",				THINGSPEC_Default},
		{ "THINGSPEC_ThingActs",			THINGSPEC_ThingActs},
		{ "THINGSPEC_ThingTargets",			THINGSPEC_ThingTargets},
		{ "THINGSPEC_TriggerTargets",		THINGSPEC_TriggerTargets},
		{ "THINGSPEC_MonsterTrigger",		THINGSPEC_MonsterTrigger},
		{ "THINGSPEC_MissileTrigger",		THINGSPEC_MissileTrigger},
		{ "THINGSPEC_ClearSpecial",			THINGSPEC_ClearSpecial},
		{ "THINGSPEC_NoDeathSpecial",		THINGSPEC_NoDeathSpecial},
		{ "THINGSPEC_TriggerActs",			THINGSPEC_TriggerActs},
		{ "THINGSPEC_Activate",				THINGSPEC_Activate},
		{ "THINGSPEC_Deactivate",			THINGSPEC_Deactivate},
		{ "THINGSPEC_Switch",				THINGSPEC_Switch},
		{ NULL, 0 }
	};

	return ParseFlagExpressionString(sc, activationstyles);
}

//==========================================================================
//
// For getting a state address from the parent
// No attempts have been made to add new functionality here
// This is strictly for keeping compatibility with old WADs!
//
//==========================================================================

static FState *CheckState(FScanner &sc, PClass *type)
{
	int v = 0;

	if (sc.GetString() && !sc.Crossed)
	{
		if (sc.Compare("0")) return NULL;
		else if (sc.Compare("PARENT"))
		{
			FState *state = NULL;
			sc.MustGetString();

			PClassActor *info = dyn_cast<PClassActor>(type->ParentClass);

			if (info != NULL)
			{
				state = info->FindState(FName(sc.String));
			}

			if (sc.GetString ())
			{
				if (sc.Compare ("+"))
				{
					sc.MustGetNumber ();
					v = sc.Number;
				}
				else
				{
					sc.UnGet ();
				}
			}

			if (state == NULL && v==0)
			{
				return NULL;
			}
			if (v != 0 && state==NULL)
			{
				sc.ScriptMessage("Attempt to get invalid state from actor %s\n", type->ParentClass->TypeName.GetChars());
				FScriptPosition::ErrorCounter++;
				return NULL;
			}
			state += v;
			return state;
		}
		else 
		{
			sc.ScriptMessage("Invalid state assignment");
			FScriptPosition::ErrorCounter++;
		}
	}
	return NULL;
}

//==========================================================================
//
// Parses an actor property's parameters and calls the handler
//
//==========================================================================

static bool ParsePropertyParams(FScanner &sc, FPropertyInfo *prop, AActor *defaults, Baggage &bag)
{
	static TArray<FPropParam> params;
	static TArray<FString> strings;

	params.Clear();
	strings.Clear();
	params.Reserve(1);
	params[0].i = 0;
	if (prop->params[0] != '0')
	{
		const char * p = prop->params;
		bool nocomma;
		bool optcomma;
		while (*p)
		{
			FPropParam conv;
			FPropParam pref;

			nocomma = false;
			conv.s = NULL;
			pref.s = NULL;
			pref.i = -1;
			bag.ScriptPosition = sc;
			switch ((*p) & 223)
			{
			case 'X':	// Expression in parentheses or number.
				{
					FxExpression *x = NULL;

					if (sc.CheckString ("("))
					{
						conv.i = -1;
						params.Push(conv);
						x = new FxDamageValue(new FxIntCast(ParseExpression(sc, bag.Info)));
						sc.MustGetStringName(")");
						conv.exp = x;
						params.Push(conv);

					}
					else
					{
						sc.MustGetNumber();
						conv.i = sc.Number;
						params.Push(conv);
						conv.exp = nullptr;
					}
				}
				break;

			case 'I':
				sc.MustGetNumber();
				conv.i = sc.Number;
				break;

			case 'F':
				sc.MustGetFloat();
				conv.d = sc.Float;
				break;

			case 'Z':	// an optional string. Does not allow any numerical value.
				if (sc.CheckFloat())
				{
					nocomma = true;
					sc.UnGet();
					break;
				}
				// fall through

			case 'S':
				sc.MustGetString();
				conv.s = strings[strings.Reserve(1)] = sc.String;
				break;

			case 'T':
				sc.MustGetString();
				conv.s = strings[strings.Reserve(1)] = strbin1(sc.String);
				break;

			case 'C':
				if (sc.CheckNumber ())
				{
					int R, G, B;
					R = clamp (sc.Number, 0, 255);
					sc.CheckString (",");
					sc.MustGetNumber ();
					G = clamp (sc.Number, 0, 255);
					sc.CheckString (",");
					sc.MustGetNumber ();
					B = clamp (sc.Number, 0, 255);
					conv.i = MAKERGB(R, G, B);
					pref.i = 0;
				}
				else
				{
					sc.MustGetString ();
					conv.s = strings[strings.Reserve(1)] = sc.String;
					pref.i = 1;
				}
				break;

			case 'M':	// special case. An expression-aware parser will not need this.
				conv.i = ParseMorphStyle(sc);
				break;
				
			case 'N':	// special case. An expression-aware parser will not need this.
				conv.i = ParseThingActivation(sc);
				break;

			case 'L':	// Either a number or a list of strings
				if (sc.CheckNumber())
				{
					pref.i = 0;
					conv.i = sc.Number;
				}
				else
				{
					pref.i = 1;
					params.Push(pref);
					params[0].i++;

					do
					{
						sc.MustGetString ();
						conv.s = strings[strings.Reserve(1)] = sc.String;
						params.Push(conv);
						params[0].i++;
					}
					while (sc.CheckString(","));
					goto endofparm;
				}
				break;

			default:
				assert(false);
				break;

			}
			if (pref.i != -1)
			{
				params.Push(pref);
				params[0].i++;
			}
			params.Push(conv);
			params[0].i++;
		endofparm:
			p++;
			// Hack for some properties that have to allow comma less
			// parameter lists for compatibility.
			if ((optcomma = (*p == '_'))) 
				p++;

			if (nocomma) 
			{
				continue;
			}
			else if (*p == 0) 
			{
				break;
			}
			else if (*p >= 'a')
			{
				if (!sc.CheckString(","))
				{
					if (optcomma)
					{
						if (!sc.CheckFloat()) break;
						else sc.UnGet();
					}
					else break;
				}
			}
			else 
			{
				if (!optcomma) sc.MustGetStringName(",");
				else sc.CheckString(",");
			}
		}
	}
	// call the handler
	try
	{
		prop->Handler(defaults, bag.Info, bag, &params[0]);
	}
	catch (CRecoverableError &error)
	{
		sc.ScriptError("%s", error.GetMessage());
	}

	return true;
}

//==========================================================================
//
// Parses an actor property
//
//==========================================================================

static void ParseActorProperty(FScanner &sc, Baggage &bag)
{
	static const char *statenames[] = {
		"Spawn", "See", "Melee", "Missile", "Pain", "Death", "XDeath", "Burn", 
		"Ice", "Raise", "Crash", "Crush", "Wound", "Disintegrate", "Heal", NULL };

	strlwr (sc.String);

	FString propname = sc.String;

	if (sc.CheckString ("."))
	{
		sc.MustGetString ();
		propname += '.';
		strlwr (sc.String);
		propname += sc.String;
	}
	else
	{
		sc.UnGet ();
	}

	FPropertyInfo *prop = FindProperty(propname);

	if (prop != NULL)
	{
		if (bag.Info->IsDescendantOf(*prop->cls))
		{
			ParsePropertyParams(sc, prop, (AActor *)bag.Info->Defaults, bag);
		}
		else
		{
			sc.ScriptMessage("'%s' requires an actor of type '%s'\n", propname.GetChars(), (*prop->cls)->TypeName.GetChars());
			FScriptPosition::ErrorCounter++;
		}
	}
	else if (MatchString(propname, statenames) != -1)
	{
		bag.statedef.SetStateLabel(propname, CheckState (sc, bag.Info));
	}
	else
	{
		sc.ScriptError("'%s' is an unknown actor property\n", propname.GetChars());
	}
}

//==========================================================================
//
// ActorActionDef
//
// Parses an action function definition. A lot of this is essentially
// documentation in the declaration for when I have a proper language
// ready.
//
//==========================================================================

static void ParseActionDef (FScanner &sc, PClassActor *cls)
{
	unsigned int error = 0;
	FName funcname;
	TArray<PType *> rets;
	
	if (sc.LumpNum == -1 || Wads.GetLumpFile(sc.LumpNum) > 0)
	{
		sc.ScriptMessage ("Action functions can only be imported by internal class and actor definitions!");
		FScriptPosition::ErrorCounter++;
	}

	sc.MustGetToken(TK_Native);
	// check for a return value
	do
	{
		if (sc.CheckToken(TK_Bool))
		{
			rets.Push(TypeBool);
		}
		else if (sc.CheckToken(TK_Int))
		{
			rets.Push(TypeSInt32);
		}
		else if (sc.CheckToken(TK_State))
		{
			rets.Push(TypeState);
		}
		else if (sc.CheckToken(TK_Float))
		{
			rets.Push(TypeFloat64);
		}
	}
	while (sc.CheckToken(','));
	sc.MustGetToken(TK_Identifier);
	funcname = sc.String;
	ParseFunctionDef(sc, cls, funcname, rets, VARF_Method | VARF_Action);
}

//==========================================================================
//
// Starts a new actor definition
//
//==========================================================================
PClassActor *CreateNewActor(const FScriptPosition &sc, FName typeName, FName parentName, bool native)
{
	PClassActor *replacee = NULL;
	PClassActor *ti = NULL;

	PClassActor *parent = RUNTIME_CLASS(AActor);

	if (parentName != NAME_None)
	{
		parent = PClass::FindActor(parentName);

		PClassActor *p = parent;
		while (p != NULL)
		{
			if (p->TypeName == typeName)
			{
				sc.Message(MSG_ERROR, "'%s' inherits from a class with the same name", typeName.GetChars());
				break;
			}
			p = dyn_cast<PClassActor>(p->ParentClass);
		}

		if (parent == NULL)
		{
			sc.Message(MSG_ERROR, "Parent type '%s' not found in %s", parentName.GetChars(), typeName.GetChars());
			parent = RUNTIME_CLASS(AActor);
		}
		else if (!parent->IsDescendantOf(RUNTIME_CLASS(AActor)))
		{
			sc.Message(MSG_ERROR, "Parent type '%s' is not an actor in %s", parentName.GetChars(), typeName.GetChars());
			parent = RUNTIME_CLASS(AActor);
		}
	}

	if (native)
	{
		ti = PClass::FindActor(typeName);
		if (ti == NULL)
		{
			extern void DumpTypeTable();
			DumpTypeTable();
			sc.Message(MSG_ERROR, "Unknown native actor '%s'", typeName.GetChars());
			goto create;
		}
		else if (ti != RUNTIME_CLASS(AActor) && ti->ParentClass->NativeClass() != parent->NativeClass())
		{
			sc.Message(MSG_ERROR, "Native class '%s' does not inherit from '%s'", typeName.GetChars(), parentName.GetChars());
			parent = RUNTIME_CLASS(AActor);
			goto create;
		}
		else if (ti->Defaults != NULL)
		{
			sc.Message(MSG_ERROR, "Redefinition of internal class '%s'", typeName.GetChars());
			goto create;
		}
		ti->InitializeNativeDefaults();
		ti->ParentClass->DeriveData(ti);
	}
	else
	{
	create:
		ti = DecoDerivedClass(sc, parent, typeName);
	}

	ti->Replacee = ti->Replacement = NULL;
	ti->DoomEdNum = -1;
	return ti;
}

//==========================================================================
//
// Starts a new actor definition
//
//==========================================================================
static PClassActor *ParseActorHeader(FScanner &sc, Baggage *bag)
{
	FName typeName;
	FName parentName;
	FName replaceName;
	bool native = false;
	int DoomEdNum = -1;

	// Get actor name
	sc.MustGetString();
	
	char *colon = strchr(sc.String, ':');
	if (colon != NULL)
	{
		*colon++ = 0;
	}

	typeName = sc.String;

	// Do some tweaking so that a definition like 'Actor:Parent' which is read as a single token is recognized as well
	// without having resort to C-mode (which disallows periods in actor names.)
	if (colon == NULL)
	{
		sc.MustGetString ();
		if (sc.String[0]==':')
		{
			colon = sc.String + 1;
		}
	}
		
	if (colon != NULL)
	{
		if (colon[0] == 0)
		{
			sc.MustGetString ();
			colon = sc.String;
		}
	}

	if (colon == NULL)
	{
		sc.UnGet();
	}

	parentName = colon;

	// Check for "replaces"
	if (sc.CheckString ("replaces"))
	{
		// Get actor name
		sc.MustGetString ();
		replaceName = sc.String;

		if (replaceName == typeName)
		{
			sc.ScriptMessage ("Cannot replace class %s with itself", typeName.GetChars());
			FScriptPosition::ErrorCounter++;
		}
	}

	// Now, after the actor names have been parsed, it is time to switch to C-mode 
	// for the rest of the actor definition.
	sc.SetCMode (true);
	if (sc.CheckNumber()) 
	{
		if (sc.Number>=-1 && sc.Number<32768) DoomEdNum = sc.Number;
		else 
		{
			// does not need to be fatal.
			sc.ScriptMessage ("DoomEdNum must be in the range [-1,32767]");
			FScriptPosition::ErrorCounter++;
		}
	}

	if (sc.CheckString("native"))
	{
		native = true;
	}

	try
	{
		PClassActor *info = CreateNewActor(sc, typeName, parentName, native);
		info->DoomEdNum = DoomEdNum > 0 ? DoomEdNum : -1;
		info->SourceLumpName = Wads.GetLumpFullPath(sc.LumpNum);

		if (!info->SetReplacement(replaceName))
		{
			sc.ScriptMessage("Replaced type '%s' not found for %s", replaceName.GetChars(), info->TypeName.GetChars());
		}

		ResetBaggage (bag, info == RUNTIME_CLASS(AActor) ? NULL : static_cast<PClassActor *>(info->ParentClass));
		bag->Info = info;
		bag->Lumpnum = sc.LumpNum;
#ifdef _DEBUG
		bag->ClassName = typeName;
#endif
		return info;
	}
	catch (CRecoverableError &err)
	{
		sc.ScriptError("%s", err.GetMessage());
		return NULL;
	}
}

//==========================================================================
//
// Reads an actor definition
//
//==========================================================================
static void ParseActor(FScanner &sc)
{
	PClassActor *info = NULL;
	Baggage bag;

	info = ParseActorHeader(sc, &bag);
	sc.MustGetToken('{');
	while (sc.MustGetAnyToken(), sc.TokenType != '}')
	{
		switch (sc.TokenType)
		{
		case TK_Action:
			ParseActionDef (sc, info);
			break;

		case TK_Const:
			ParseConstant (sc, &info->Symbols, info);
			break;

		case TK_Enum:
			ParseEnum (sc, &info->Symbols, info);
			break;

		case TK_Native:
			ParseNativeFunction (sc, info);
			break;

		case TK_Var:
			ParseUserVariable (sc, &info->Symbols, info);
			break;

		case TK_Identifier:
			ParseActorProperty(sc, bag);
			break;

		case TK_States:
			if (bag.StateSet) 
			{
				sc.ScriptMessage("'%s' contains multiple state declarations", bag.Info->TypeName.GetChars());
				FScriptPosition::ErrorCounter++;
			}
			ParseStates(sc, bag.Info, (AActor *)bag.Info->Defaults, bag);
			bag.StateSet = true;
			break;

		case '+':
		case '-':
			ParseActorFlag(sc, bag, sc.TokenType);
			break;

		default:
			sc.ScriptError("Unexpected '%s' in definition of '%s'", sc.String, bag.Info->TypeName.GetChars());
			break;
		}
	}
	if (bag.DropItemSet)
	{
		bag.Info->SetDropItems(bag.DropItemList);
	}
	try
	{
		info->Finalize(bag.statedef);
	}
	catch (CRecoverableError &err)
	{
		sc.ScriptError("%s", err.GetMessage());
	}
	sc.SetCMode (false);
}

//==========================================================================
//
// Reads a damage definition
//
//==========================================================================

static void ParseDamageDefinition(FScanner &sc)
{
	sc.SetCMode (true); // This may be 100% irrelevant for such a simple syntax, but I don't know

	// Get DamageType

	sc.MustGetString();
	FName damageType = sc.String;

	DamageTypeDefinition dtd;

	sc.MustGetToken('{');
	while (sc.MustGetAnyToken(), sc.TokenType != '}')
	{
		if (sc.Compare("FACTOR"))
		{
			sc.MustGetFloat();
			dtd.DefaultFactor = sc.Float;
			if (dtd.DefaultFactor == 0) dtd.ReplaceFactor = true;
		}
		else if (sc.Compare("REPLACEFACTOR"))
		{
			dtd.ReplaceFactor = true;
		}
		else if (sc.Compare("NOARMOR"))
		{
			dtd.NoArmor = true;
		}
		else
		{
			sc.ScriptError("Unexpected data (%s) in damagetype definition.", sc.String);
		}
	}

	dtd.Apply(damageType);

	sc.SetCMode (false); // (set to true earlier in function)
}

//==========================================================================
//
// ParseDecorate
//
// Parses a single DECORATE lump
//
//==========================================================================

void ParseDecorate (FScanner &sc)
{
	// Get actor class name.
	for(;;)
	{
		FScanner::SavedPos pos = sc.SavePos();
		if (!sc.GetToken ())
		{
			return;
		}
		switch (sc.TokenType)
		{
		case TK_Include:
		{
			sc.MustGetString();
			// This check needs to remain overridable for testing purposes.
			if (Wads.GetLumpFile(sc.LumpNum) == 0 && !Args->CheckParm("-allowdecoratecrossincludes"))
			{
				int includefile = Wads.GetLumpFile(Wads.CheckNumForFullName(sc.String, true));
				if (includefile != 0)
				{
					I_FatalError("File %s is overriding core lump %s.",
						Wads.GetWadFullName(includefile), sc.String);
				}
			}
			FScanner newscanner;
			newscanner.Open(sc.String);
			ParseDecorate(newscanner);
			break;
		}

		case TK_Const:
			ParseConstant (sc, &GlobalSymbols, NULL);
			break;

		case TK_Enum:
			ParseEnum (sc, &GlobalSymbols, NULL);
			break;

		case ';':
			// ';' is the start of a comment in the non-cmode parser which
			// is used to parse parts of the DECORATE lump. If we don't add 
			// a check here the user will only get weird non-informative
			// error messages if a semicolon is found.
			sc.ScriptError("Unexpected ';'");
			break;

		case TK_Identifier:
			// 'ACTOR' cannot be a keyword because it is also needed as a class identifier
			// so let's do a special case for this.
			if (sc.Compare("ACTOR"))
			{
				ParseActor (sc);
				break;
			}
			else if (sc.Compare("PICKUP"))
			{
				ParseOldDecoration (sc, DEF_Pickup);
				break;
			}
			else if (sc.Compare("BREAKABLE"))
			{
				ParseOldDecoration (sc, DEF_BreakableDecoration);
				break;
			}
			else if (sc.Compare("PROJECTILE"))
			{
				ParseOldDecoration (sc, DEF_Projectile);
				break;
			}
			else if (sc.Compare("DAMAGETYPE"))
			{
				ParseDamageDefinition(sc);
				break;
			}
		default:
			sc.RestorePos(pos);
			ParseOldDecoration(sc, DEF_Decoration);
			break;
		}
	}
}

void ParseAllDecorate()
{
	int lastlump = 0, lump;

	while ((lump = Wads.FindLump("DECORATE", &lastlump)) != -1)
	{
		FScanner sc(lump);
		ParseDecorate(sc);
	}
}