#ifndef GUARD_PROGRAMMEMORY_H
#define GUARD_PROGRAMMEMORY_H

#include "config.h"
#include "utils.h"
#include "valueflow.h" // needed for alias
#include "mathlib.h"
#include <map>
#include <unordered_map>

class Token;

struct ProgramMemory {
 using Map = std::unordered_map<nonneg int, ValueFlow::Value>;
 Map values;

 void setValue(nonneg int varid, const ValueFlow::Value &value);

 bool getIntValue(nonneg int varid, MathLib::bigint* result) const;
 void setIntValue(nonneg int varid, MathLib::bigint value);

 void setUnknown(nonneg int varid);

 bool getTokValue(nonneg int varid, const Token** result) const;
 bool hasValue(nonneg int varid);

 void swap(ProgramMemory &pm);

 void clear();

 bool empty() const;

 void replace(const ProgramMemory &pm);

 void insert(const ProgramMemory &pm);
};

struct ProgramMemoryState {
 ProgramMemory state;
 std::map<nonneg int, const Token*> origins;

 void insert(const ProgramMemory &pm, const Token* origin = nullptr);
 void replace(const ProgramMemory &pm, const Token* origin = nullptr);

 void addState(const Token* tok, const ProgramMemory::Map& vars);

 void assume(const Token* tok, bool b);

 void removeModifiedVars(const Token* tok);

 ProgramMemory get(const Token *tok, const ProgramMemory::Map& vars) const;

};

void execute(const Token *expr,
 ProgramMemory * const programMemory,
 MathLib::bigint *result,
 bool *error);

/**
 * Is condition always false when variable has given value?
 * \param condition top ast token in condition
 * \param programMemory program memory
 */
bool conditionIsFalse(const Token *condition, const ProgramMemory &programMemory);

/**
 * Is condition always true when variable has given value?
 * \param condition top ast token in condition
 * \param programMemory program memory
 */
bool conditionIsTrue(const Token *condition, const ProgramMemory &programMemory);

/**
 * Get program memory by looking backwards from given token.
 */
ProgramMemory getProgramMemory(const Token *tok, nonneg int varid, const ValueFlow::Value &value);

ProgramMemory getProgramMemory(const Token *tok, const ProgramMemory::Map& vars);

#endif