#ifndef TNZ_EXPRESSIONFIELD_INCLUDED
#define TNZ_EXPRESSIONFIELD_INCLUDED

#include "tw/textfield.h"

#undef DVAPI
#undef DVVAR
#ifdef TWIN_EXPORTS
#define DVAPI DV_EXPORT_API
#define DVVAR DV_EXPORT_VAR
#else
#define DVAPI DV_IMPORT_API
#define DVVAR DV_IMPORT_VAR
#endif

#ifdef WIN32
#pragma warning(push)
#pragma warning(disable : 4251)
#endif

// forward declaration
namespace TSyntax
{
class Parser;
class Grammar;
}

class DVAPI TExpressionField : public TTextField
{
public:
	class Listener
	{
	public:
		virtual void onExpressionChange(string s, bool isValid) = 0;
		virtual ~Listener() {}
	};

	TSyntax::Parser *m_parser;
	Listener *m_listener;
	void apply();

public:
	TExpressionField(TWidget *parent, string name = "expressionField");
	~TExpressionField();

	void setGrammar(TSyntax::Grammar *grammar);
	TSyntax::Grammar *getGrammar() const;

	void setListener(Listener *listener)
	{
		m_listener = listener;
	}

	void keyDown(int key, TUINT32 status, const TPoint &p);
	void drawFieldText(const TPoint &origin, wstring text);

	string getError() const;
};

#ifdef WIN32
#pragma warning(pop)
#endif

#endif