scummvm/engines/bagel/baglib/expression.h
2024-05-05 13:27:01 +02:00

131 lines
4.8 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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/>.
*
*/
#ifndef BAGEL_BAGLIB_EXPRESSION_H
#define BAGEL_BAGLIB_EXPRESSION_H
#include "bagel/baglib/parse_object.h"
#include "bagel/baglib/var.h"
#include "bagel/boflib/list.h"
namespace Bagel {
class CBagExpression : public CBagParseObject, public CBofObject {
public:
enum OPERATION {
OP_NONE,
OP_ASSIGN,
OP_EQUAL,
OP_NOT_EQUAL,
OP_LESS_THAN,
OP_LESS_THAN_EQUAL,
OP_GREATER_THAN,
OP_GREATER_THAN_EQUAL,
OP_PLUS_ASSIGN,
OP_MINUS_ASSIGN,
OP_CONTAINS,
OP_HAS,
OP_CURR_SDEV,
OP_PLUS,
OP_MINUS,
OP_MULTIPLY,
OP_DIVIDE,
OP_AND,
OP_OR,
OP_MOD,
OP_STATUS
};
private:
CBofList<CBagVar *> _varList; // Right hand operator
CBofList<OPERATION> _operList; // Operation to be preformed
CBagExpression *_prevExpression; // Not null when when this is an enclosed expression
bool _prevNegativeFl; // True if the operation should return Negative results
bool _negativeFl; // True if the operation should return Negative results
bool evaluate(CBagVar *leftHandOper, CBagVar *rightHandOper, OPERATION oper, CBagVar &result);
public:
static CBagVar *_tempVar; // Used as a default param
static void initialize();
static void shutdown();
CBagExpression(CBagExpression *prevExpr = nullptr, bool prevNegFl = false);
virtual ~CBagExpression();
bool evaluate(bool negFl = false, CBagVar &result = *_tempVar);
/**
* Same as evaluate above except it evaluates left to right and preserves
* the value of the previous evaluation in the loop. Provides partial
* evaluation hierarchy support.
*/
bool evalLeftToRight(bool negFl = false, CBagVar &result = *_tempVar);
bool negEvaluate(CBagVar &result = *_tempVar);
void setNegative(bool b = true) {
_negativeFl = b;
}
bool isNegative() const {
return _negativeFl;
}
CBagVar *getVariable(int itemPos);
OPERATION getOperation(int itemPos);
ParseCodes setInfo(CBagIfstream &istr) override;
ErrorCode getOperatorFromStream(CBagIfstream &istr, OPERATION &oper);
CBagExpression *getPrevExpression() const {
return _prevExpression;
}
void setPrevExpression(CBagExpression *expr) {
_prevExpression = expr;
}
virtual bool onAssign(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onEqual(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onNotEqual(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onLessThan(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onGreaterThan(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onLessThanEqual(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onGreaterThanEqual(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onPlusAssign(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onMinusAssign(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onContains(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onHas(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onCurrSDev(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onPlus(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onMinus(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onMultiply(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onDivide(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onMod(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onAnd(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onOr(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
virtual bool onStatus(CBagVar *leftHandOper, CBagVar *rightHandOper, CBagVar &resultOper);
};
} // namespace Bagel
#endif