/* Copyright (C) 1996, Russell Lang.  All rights reserved.
  
  This file is part of Aladdin Ghostscript.
  
  Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
  or distributor accepts any responsibility for the consequences of using it,
  or for whether it serves any particular purpose or works at all, unless he
  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin Ghostscript must include a copy of the License,
  normally in a plain ASCII text file named PUBLIC.  The License grants you
  the right to copy, modify and redistribute Aladdin Ghostscript, but only
  under certain conditions described in the License.  Among other things, the
  License requires that the copyright notice and this notice be preserved on
  all copies.
*/


// dwdll.h

// gsdll_class for MS-Windows

#ifndef _GSDLL_H
extern "C" {
#include "gsdll.h"
}
#endif

#ifndef _GSDLL_CLASS_H
#define _GSDLL_CLASS_H


class gsdll_class {
	// instance of caller
	HINSTANCE	hinstance;
	// handle to DLL.  Non-zero of loaded.
	HINSTANCE	hmodule;
	// handle to parent window.  Can be NULL.
	HWND		hwnd;
	// text description of last error
	char		last_error[128];
	// true if init and execute_begin have been called
	BOOL		initialized;
	// return code from last c_execute_end
	int		execute_code;

	// pointer to callback from DLL
	GSDLL_CALLBACK callback;

	// pointers to DLL functions
	PFN_gsdll_revision	c_revision;
	PFN_gsdll_init		c_init;
	PFN_gsdll_execute_begin	c_execute_begin;
	PFN_gsdll_execute_cont	c_execute_cont;
	PFN_gsdll_execute_end	c_execute_end;
	PFN_gsdll_exit		c_exit;
	PFN_gsdll_lock_device	c_lock_device;
	PFN_gsdll_copy_dib	c_copy_dib;
	PFN_gsdll_copy_palette	c_copy_palette;
	PFN_gsdll_draw		c_draw;

	// pointer to os2dll or mswindll device
	// this needs to be extended to support multiple devices
	// also need to have one window per device
	char FAR *device;


public:
	// Load DLL
	// Arguments:
	//   instance of calling EXE
	//   name of DLL, may include path
	//   expected version number of DLL
	// Returns:
	//   zero on success
	//   non-zero on error.  Error message available from get_last_error()
	// do nothing if DLL already loaded
	int load(const HINSTANCE hinstance, const char *name, const long version);

	// Get revision number of DLL
	int revision(char FAR * FAR *, char FAR * FAR *, long FAR *, long FAR *);

	// Unload DLL
	int unload(void);
	
	// Initialise DLL
	// Arguments:
	//   pointer to C callback function
	//   window handle of parent
	//   argc  (normal C command line)
	//   argv  (normal C command line)
	int init(GSDLL_CALLBACK callback, HWND hwnd, int argc, char FAR * FAR *argv);

	// Restart DLL
	int restart(int argc, char FAR * FAR *argv);

	// Execute string
	int execute(const char FAR *, int len);

	// Get last error string
	int get_last_error(char *str, int len);

	// lock device
	int gsdll_class::lock_device(const char FAR *device, int lock);

	// draw bitmap
	int gsdll_class::draw(const char FAR *device, HDC hdc, int dx, int dy, int wx, int wy, int sx, int sy);

	// copy bitmap
  	HGLOBAL gsdll_class::copy_dib(const char FAR *device);

	// copy palette
  	HPALETTE gsdll_class::copy_palette(const char FAR *device);
};
#endif // _GSDLL_CLASS_H