// license:GPL-2.0+
// copyright-holders:Raphael Nabet
/*****************************************************************************
 *
 * includes/pdp1.h
 *
 ****************************************************************************/

#ifndef PDP1_H_
#define PDP1_H_

#include "cpu/pdp1/pdp1.h"
#include "video/crt.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 */
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 puncher registers */
struct tape_puncher_t
{
	device_image_interface *fd; /* file descriptor of tape image */

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



/* typewriter registers */
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 */
};

/* MIT parallel drum (mostly similar to type 23) */
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 */
};


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


class pdp1_state : public driver_device
{
public:
	pdp1_state(const machine_config &mconfig, device_type type, const char *tag)
		: driver_device(mconfig, type, tag),
		m_maincpu(*this, "maincpu"),
		m_gfxdecode(*this, "gfxdecode"),
		m_palette(*this, "palette"),
		m_crt(*this, "crt"),
		m_spacewar(*this, "SPACEWAR"),
		m_csw(*this, "CSW"),
		m_sense(*this, "SENSE"),
		m_tstadd(*this, "TSTADD"),
		m_twdmsb(*this, "TWDMSB"),
		m_twdlsb(*this, "TWDLSB"),
		m_twr(*this, "TWR"),
		m_cfg(*this, "CFG"),
		m_io_lightpen(*this, "LIGHTPEN"),
		m_lightx(*this, "LIGHTX"),
		m_lighty(*this, "LIGHTY")
	{ }

	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;
	required_device<pdp1_device> m_maincpu;

	virtual void machine_start() override;
	virtual void machine_reset() override;
	virtual void video_start() override;
	DECLARE_PALETTE_INIT(pdp1);
	UINT32 screen_update_pdp1(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect);
	void screen_eof_pdp1(screen_device &screen, bool state);
	INTERRUPT_GEN_MEMBER(pdp1_interrupt);
	TIMER_CALLBACK_MEMBER(reader_callback);
	TIMER_CALLBACK_MEMBER(puncher_callback);
	TIMER_CALLBACK_MEMBER(tyo_callback);
	TIMER_CALLBACK_MEMBER(dpy_callback);
	void pdp1_machine_stop();
	inline void pdp1_plot_pixel(bitmap_ind16 &bitmap, int x, int y, UINT32 color);
	void pdp1_plot(int x, int y);
	void pdp1_draw_led(bitmap_ind16 &bitmap, int x, int y, int state);
	void pdp1_draw_multipleled(bitmap_ind16 &bitmap, int x, int y, int value, int nb_bits);
	void pdp1_draw_switch(bitmap_ind16 &bitmap, int x, int y, int state);
	void pdp1_draw_multipleswitch(bitmap_ind16 &bitmap, int x, int y, int value, int nb_bits);
	void pdp1_draw_char(bitmap_ind16 &bitmap, char character, int x, int y, int color);
	void pdp1_draw_string(bitmap_ind16 &bitmap, const char *buf, int x, int y, int color);
	void pdp1_draw_panel_backdrop(bitmap_ind16 &bitmap);
	void pdp1_draw_panel(bitmap_ind16 &bitmap);
	void pdp1_typewriter_linefeed();
	void pdp1_typewriter_drawchar(int character);
	void pdp1_update_lightpen_state(const lightpen_t *new_state);
	void pdp1_draw_circle(bitmap_ind16 &bitmap, int x, int y, int radius, int color_);
	void pdp1_erase_lightpen(bitmap_ind16 &bitmap);
	void pdp1_draw_lightpen(bitmap_ind16 &bitmap);
	int tape_read(UINT8 *reply);
	void begin_tape_read(int binary, int nac);
	void tape_write(UINT8 data);
	void typewriter_out(UINT8 data);
	void parallel_drum_set_il(int il);
	UINT32 drum_read(int field, int position);
	void drum_write(int field, int position, UINT32 data);
	void pdp1_keyboard();
	void pdp1_lightpen();
	int read_spacewar() { return m_spacewar->read(); }

private:
	pdp1_reset_param_t m_reset_param;
	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_ind16 m_panel_bitmap;
	bitmap_ind16 m_typewriter_bitmap;
	lightpen_t m_lightpen_state;
	lightpen_t m_previous_lightpen_state;
	int m_pos;
	int m_case_shift;
	required_device<gfxdecode_device> m_gfxdecode;
	required_device<palette_device> m_palette;
	required_device<crt_device> m_crt;
	required_ioport m_spacewar;
	required_ioport m_csw;
	required_ioport m_sense;
	required_ioport m_tstadd;
	required_ioport m_twdmsb;
	required_ioport m_twdlsb;
	required_ioport_array<4> m_twr;
	required_ioport m_cfg;
	required_ioport m_io_lightpen;
	required_ioport m_lightx;
	required_ioport m_lighty;
};
#endif /* PDP1_H_ */
