* It provides an easy to use interface to the screen.   It is also

 * responsible for starting the TADS2/3 VM.

 *

 * This class defines an abstract screen I/O interface which has to be

 * implemented in an API-specific subclass.

 */

#ifndef FROBTADSAPP_H

#define FROBTADSAPP_H

#include "common.h"

#include "os.h"

extern "C" {

#include "osgen.h"

}

/* Global application pointer.

 */

extern class FrobTadsApplication* globalApp;

class FrobTadsApplication {

  public:

	// Signal handlers are such a pain in the ass...  Has to be

	// friend.

	friend RETSIGTYPE winResizeHandler(int);

	// Instead of using a gazillion of constructor-arguments, we

	// group them inside this structure.

	struct FrobOptions {

		bool useColors;         // Enable colors?

		bool forceColors;       // Force colors?

		bool defColors;         // Use default colors for color pair 0?

		bool softScroll;        // Scroll softly?

		bool exitPause;         // Pause prior to exit?

		bool changeDir;         // Change to the game's directory?

		int textColor;          // Default text color.

		int bgColor;            // Default background color.

		int statTextColor;      // Default text color of statusline.

		int statBgColor;        // Default background color of statusline.

		unsigned scrollBufSize; // Scroll-back buffer size.

		int safetyLevel;        // File I/O safety level.

		char characterSet[40];  // Local character set name.

	};

	// Our options.  Once set, they remain constant during run-time

	// so there's no reason to protect them.

	const FrobOptions options;

  private:

	/* Runs the T2VM.

	 */

	int

	fRunTads2( char* filename );

	/* Runs the T3VM.

	 */

	int

	fRunTads3( char* filename );

  protected:

	// We store the remaining input-timeout here in case a

	// window-resize occurs; the signal handler can then restore it.

	int fRemainingTimeout;

	// Are we using colors?

	bool fColorsEnabled;

  public:

	FrobTadsApplication( const FrobOptions& opts );

	/* Are colors enabled?

	 */

	bool

	colorsEnabled() const

	{ return this->fColorsEnabled; }

	/* Starts the VM and returns its exit code.  Which VM is started

	 * is given by the 'vm' argument: 0 for TADS2, non-0 for TADS3.

	 */

	int

	runTads( const char* filename, int vm );

	/* Change the current working directory, if possible.  Returns

	 * true on success, false on failure.

	 */

	bool

	changeDirectory( const char* dir );

	/* ============================================================

	 * Pure virtual functions follow.  This is the interface that

	 * has to be implemented in an API-specific subclass.

	 * ============================================================

	 */

  protected:

	/* Initialize the display.  This is called once just prior to

	 * starting a game.

	 */

	virtual void

	init() = 0;

	/* Re-initialize the display and any internal book-keeping data

	 * if needed.  This is called every time the terminal

	 * dimensions change.  This usually means the new dimensions

	 * have to be detected and a new output window will be created.

	 */

	virtual void

	resizeEvent() = 0;

  public:

	/* Moves the cursor to the specified position.

	 */

	virtual void

	moveCursor( int line, int column ) = 0;

	/* Prints a string at the specified position, using 'attrs' as

	 * atributes.

	 */

	virtual void

	print( int line, int column, int attrs, const char* str ) = 0;

	/* Flush any pending output.  That means everything that is not

	 * printed yet due to buffered output (if applicable) should be

	 * printed now.

	 */

	virtual void

	flush() = 0;

	/* Clears a portion of the screen.

	 */

	virtual void

	clear( int top, int left, int bottom, int right, int attrs ) = 0;

	/* Scroll the specified region of the screen 1 line up/down.

	 * 'attrs' holds the attributes of the generated empty lines.

	 */

	virtual void

	scrollRegionUp( int top, int left, int bottom, int right, int attrs ) = 0;

	virtual void

	scrollRegionDown( int top, int left, int bottom, int right, int attrs ) = 0;

	/* Reads a character from the keyboard and returns it.  If a

	 * function key has been pressed, then a curses KEY_* value is

	 * returned (have a look at your system's <curses.h> header for

	 * a list of KEY_ macros).

	 *

	 * If 'cursorVisible' is false, no cursor is shown while waiting

	 * for a key-press.

	 *

	 * If 'timeout' is > 0, then the routine will wait for a key

	 * only for 'timeout' milliseconds.  If a key has been pressed

	 * before the timeout expires it is returned as usual.  If the

	 * timeout expires and there's still no key, ERR is returned.

	 *

	 * Note that KEY_BACKSPACE and KEY_DL are handled correctly; you

	 * don't need to use the low-level curses routines erasechar()

	 * and killchar().  Just check for KEY_BACKSPACE and KEY_DL.

	 */

	virtual int

	getRawChar( bool cursorVisible, int timeout ) = 0;

	/* Pause for 'ms' milliseconds.

	 */

	virtual void

	sleep( int ms ) = 0;

	/* Returns the height (lines) of the screen.

	 */

	virtual int

	height() const = 0;

	/* Returns the width (columns) of the screen.

	 */

	virtual int

	width() const = 0;

};