/*****************************************************************************
 *
 * includes/pdp1.h
 *
 ****************************************************************************/

#ifndef PDP1_H_
#define PDP1_H_


/* defines for each bit and mask in input port "CSW" */
enum
{
	/* bit numbers */
	pdp1_control_bit = 0,

	pdp1_extend_bit		= 1,
	pdp1_start_nobrk_bit= 2,
	pdp1_start_brk_bit	= 3,
	pdp1_stop_bit		= 4,
	pdp1_continue_bit	= 5,
	pdp1_examine_bit	= 6,
	pdp1_deposit_bit	= 7,
	pdp1_read_in_bit	= 8,
	pdp1_reader_bit		= 9,
	pdp1_tape_feed_bit	= 10,
	pdp1_single_step_bit= 11,
	pdp1_single_inst_bit= 12,

	/* masks */
	pdp1_control = (1 << pdp1_control_bit),
	pdp1_extend = (1 << pdp1_extend_bit),
	pdp1_start_nobrk = (1 << pdp1_start_nobrk_bit),
	pdp1_start_brk = (1 << pdp1_start_brk_bit),
	pdp1_stop = (1 << pdp1_stop_bit),
	pdp1_continue = (1 << pdp1_continue_bit),
	pdp1_examine = (1 << pdp1_examine_bit),
	pdp1_deposit = (1 << pdp1_deposit_bit),
	pdp1_read_in = (1 << pdp1_read_in_bit),
	pdp1_reader = (1 << pdp1_reader_bit),
	pdp1_tape_feed = (1 << pdp1_tape_feed_bit),
	pdp1_single_step = (1 << pdp1_single_step_bit),
	pdp1_single_inst = (1 << pdp1_single_inst_bit)
};

/* defines for each bit in input port pdp1_spacewar_controllers*/
#define ROTATE_LEFT_PLAYER1       0x01
#define ROTATE_RIGHT_PLAYER1      0x02
#define THRUST_PLAYER1            0x04
#define FIRE_PLAYER1              0x08
#define ROTATE_LEFT_PLAYER2       0x10
#define ROTATE_RIGHT_PLAYER2      0x20
#define THRUST_PLAYER2            0x40
#define FIRE_PLAYER2              0x80
#define HSPACE_PLAYER1            0x100
#define HSPACE_PLAYER2            0x200

/* defines for each field in input port pdp1_config */
enum
{
	pdp1_config_extend_bit			= 0,
	pdp1_config_extend_mask			= 0x3,	/* 2 bits */
	pdp1_config_hw_mul_div_bit		= 2,
	pdp1_config_hw_mul_div_mask		= 0x1,
	/*pdp1_config_hw_obsolete_bit   = 3,
    pdp1_config_hw_obsolete_mask    = 0x1,*/
	pdp1_config_type_20_sbs_bit		= 4,
	pdp1_config_type_20_sbs_mask	= 0x1,
	pdp1_config_lightpen_bit		= 5,
	pdp1_config_lightpen_mask		= 0x1
};

/* defines for each field in input port pdp1_lightpen_state */
enum
{
	pdp1_lightpen_down_bit			= 0,
	pdp1_lightpen_smaller_bit		= 1,
	pdp1_lightpen_larger_bit		= 2,

	pdp1_lightpen_down				= (1 << pdp1_lightpen_down_bit),
	pdp1_lightpen_smaller			= (1 << pdp1_lightpen_smaller_bit),
	pdp1_lightpen_larger			= (1 << pdp1_lightpen_larger_bit)
};

/* defines for our font */
enum
{
	pdp1_charnum = /*104*/128,	/* ASCII set + 8 special characters */
									/* for whatever reason, 104 breaks some characters */

	pdp1_fontdata_size = 8 * pdp1_charnum
};

enum
{
	/* size and position of crt window */
	crt_window_width = 512,
	crt_window_height = 512,
	crt_window_offset_x = 0,
	crt_window_offset_y = 0,
	/* size and position of operator control panel window */
	panel_window_width = 384,
	panel_window_height = 128,
	panel_window_offset_x = crt_window_width,
	panel_window_offset_y = 0,
	/* size and position of typewriter window */
	typewriter_window_width = 640,
	typewriter_window_height = 160,
	typewriter_window_offset_x = 0,
	typewriter_window_offset_y = crt_window_height
};

enum
{
	total_width = crt_window_width + panel_window_width,
	total_height = crt_window_height + typewriter_window_height,

	/* respect 4:3 aspect ratio to keep pixels square */
	virtual_width_1 = ((total_width+3)/4)*4,
	virtual_height_1 = ((total_height+2)/3)*3,
	virtual_width_2 = virtual_height_1*4/3,
	virtual_height_2 = virtual_width_1*3/4,
	virtual_width = (virtual_width_1 > virtual_width_2) ? virtual_width_1 : virtual_width_2,
	virtual_height = (virtual_height_1 > virtual_height_2) ? virtual_height_1 : virtual_height_2
};

enum
{	/* refresh rate in Hz: can be changed at will */
	refresh_rate = 60
};

/* Color codes */
enum
{
	/* first pen_crt_num_levels colors used for CRT (with remanence) */
	pen_crt_num_levels = 69,
	pen_crt_max_intensity = pen_crt_num_levels-1,

	/* next colors used for control panel and typewriter */
	pen_black = pen_crt_num_levels,
	pen_white,
	pen_green,
	pen_dk_green,
	pen_red,
	pen_lt_gray,

	/* color constants for control panel */
	pen_panel_bg = pen_black,
	pen_panel_caption = pen_white,
	color_panel_caption = 0,
	pen_switch_nut = pen_lt_gray,
	pen_switch_button = pen_white,
	pen_lit_lamp = pen_green,
	pen_unlit_lamp = pen_dk_green,

	/* color constants for typewriter */
	pen_typewriter_bg = pen_white,
	color_typewriter_black = 1,
	color_typewriter_red = 2,

	/* color constants used for light pen */
	pen_lightpen_nonpressed = pen_red,
	pen_lightpen_pressed = pen_green
};

/* tape reader registers */
typedef struct tape_reader_t
{
	device_image_interface *fd;	/* file descriptor of tape image */

	int motor_on;	/* 1-bit reader motor on */

	int rb;			/* 18-bit reader buffer */
	int rcl;		/* 1-bit reader clutch */
	int rc;			/* 2-bit reader counter */
	int rby;		/* 1-bit reader binary mode flip-flop */
	int rcp;		/* 1-bit reader "need a completion pulse" flip-flop */

	emu_timer *timer;	/* timer to simulate reader timing */
} tape_reader_t;



/* tape puncher registers */
typedef struct tape_puncher_t
{
	device_image_interface *fd;	/* file descriptor of tape image */

	emu_timer *timer;	/* timer to generate completion pulses */
} tape_puncher_t;



/* typewriter registers */
typedef struct typewriter_t
{
	device_image_interface *fd;	/* file descriptor of output image */

	int tb;			/* typewriter buffer */

	emu_timer *tyo_timer;/* timer to generate completion pulses */
} typewriter_t;

/* MIT parallel drum (mostly similar to type 23) */
typedef struct parallel_drum_t
{
	device_image_interface *fd;	/* file descriptor of drum image */

	int il;			/* initial location (12-bit) */
	int wc;			/* word counter (12-bit) */
	int wcl;		/* word core location counter (16-bit) */
	int rfb;		/* read field buffer (5-bit) */
	int wfb;		/* write field buffer (5-bit) */

	int dba;

	emu_timer *rotation_timer;	/* timer called each time dc is 0 */
	emu_timer *il_timer;		/* timer called each time dc is il */
} parallel_drum_t;


typedef struct lightpen_t
{
	char active;
	char down;
	short x, y;
	short radius;
} lightpen_t;


class pdp1_state : public driver_device
{
public:
	pdp1_state(const machine_config &mconfig, device_type type, const char *tag)
		: driver_device(mconfig, type, tag) { }

	pdp1_reset_param_t m_reset_param;
	int m_io_status;
	tape_reader_t m_tape_reader;
	tape_puncher_t m_tape_puncher;
	typewriter_t m_typewriter;
	emu_timer *m_dpy_timer;
	lightpen_t m_lightpen;
	parallel_drum_t m_parallel_drum;
	int m_old_typewriter_keys[4];
	int m_old_lightpen;
	int m_old_control_keys;
	int m_old_tw_keys;
	int m_old_ta_keys;
	int m_typewriter_color;
	bitmap_t *m_panel_bitmap;
	bitmap_t *m_typewriter_bitmap;
	lightpen_t m_lightpen_state;
	lightpen_t m_previous_lightpen_state;
	int m_pos;
	int m_case_shift;
	device_t *m_crt;
};



/*----------- defined in video/pdp1.c -----------*/

VIDEO_START( pdp1 );
SCREEN_EOF( pdp1 );
SCREEN_UPDATE( pdp1 );

void pdp1_plot(running_machine &machine, int x, int y);
void pdp1_typewriter_drawchar(running_machine &machine, int character);
void pdp1_update_lightpen_state(running_machine &machine, const lightpen_t *new_state);


#endif /* PDP1_H_ */
