/*
 * Copyright (c) 2006-2018, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2006-09-15     QiuYi        the first version
 * 2017-08-16     Parai        the 2nd version
 */

#include <rtthread.h>
#include <rthw.h>

#include <bsp.h>
#include "keyboard.h"
#include "keymap.h"

#define FALSE RT_FALSE
#define TRUE  RT_TRUE
#define PRIVATE static
#define PUBLIC 
#define t_bool  rt_bool_t
#define t_8     rt_uint8_t
#define t_32    rt_uint32_t

PRIVATE	KB_INPUT	kb_in;
PRIVATE	t_bool		code_with_E0	= FALSE;
PRIVATE	t_bool		shift_l;		/* l shift state	*/
PRIVATE	t_bool		shift_r;		/* r shift state	*/
PRIVATE	t_bool		alt_l;			/* l alt state		*/
PRIVATE	t_bool		alt_r;			/* r left state		*/
PRIVATE	t_bool		ctrl_l;			/* l ctrl state		*/
PRIVATE	t_bool		ctrl_r;			/* l ctrl state		*/
PRIVATE	t_bool		caps_lock;		/* Caps Lock		*/
PRIVATE	t_bool		num_lock;		/* Num Lock		*/
PRIVATE	t_bool		scroll_lock;		/* Scroll Lock		*/
PRIVATE	int		column		= 0;	/* keyrow[column] is one value of keymap */

PRIVATE t_8	get_byte_from_kb_buf();
PRIVATE void	set_leds();
PRIVATE void	kb_wait();
PRIVATE void	kb_ack();

PUBLIC void init_keyboard()
{
	kb_in.count = 0;
	kb_in.p_head = kb_in.p_tail = kb_in.buf;

	caps_lock	= 0;
	num_lock	= 1;
	scroll_lock	= 0;

	set_leds();
}
PUBLIC rt_bool_t keyboard_read(rt_uint32_t *pkey)
{
	t_8	scan_code;
	t_bool	make;	/* TRUE : make  */
			/* FALSE: break */
	t_32	key = 0;
	t_32*	keyrow;

	if(kb_in.count > 0){
		code_with_E0 = FALSE;
		scan_code = get_byte_from_kb_buf();

		/* start scan */
		if (scan_code == 0xE1) {
			int i;
			static const t_8 pausebreak_scan_code[] = {0xE1, 0x1D, 0x45, 0xE1, 0x9D, 0xC5};
			t_bool is_pausebreak = TRUE;
			for(i=1;i<6;i++){
				if (get_byte_from_kb_buf() != pausebreak_scan_code[i]) {
					is_pausebreak = FALSE;
					break;
				}
			}
			if (is_pausebreak) {
				key = PAUSEBREAK;
			}
		}
		else if (scan_code == 0xE0) {
			code_with_E0 = TRUE;
			scan_code = get_byte_from_kb_buf();

			/* PrintScreen pressed */
			if (scan_code == 0x2A) {
				code_with_E0 = FALSE;
				if ((scan_code = get_byte_from_kb_buf()) == 0xE0) {
					code_with_E0 = TRUE;
					if ((scan_code = get_byte_from_kb_buf()) == 0x37) {
						key = PRINTSCREEN;
						make = TRUE;
					}
				}
			}
			/* PrintScreen released */
			else if (scan_code == 0xB7) {
				code_with_E0 = FALSE;
				if ((scan_code = get_byte_from_kb_buf()) == 0xE0) {
					code_with_E0 = TRUE;
					if ((scan_code = get_byte_from_kb_buf()) == 0xAA) {
						key = PRINTSCREEN;
						make = FALSE;
					}
				}
			}
		} /* if is not PrintScreen, scan_code is the one after 0xE0 */
		if ((key != PAUSEBREAK) && (key != PRINTSCREEN)) {
			/* is Make Code or Break Code */
			make = (scan_code & FLAG_BREAK ? FALSE : TRUE);
			
			keyrow = &keymap[(scan_code & 0x7F) * MAP_COLS];

			column = 0;

			t_bool caps = shift_l || shift_r;
			if (caps_lock) {
				if ((keyrow[0] >= 'a') && (keyrow[0] <= 'z')){
					caps = !caps;
				}
			}
			if (caps) {
				column = 1;
			}

			if (code_with_E0) {
				column = 2;
			}

			key = keyrow[column];

			switch(key) {
			case SHIFT_L:
				shift_l	= make;
				break;
			case SHIFT_R:
				shift_r	= make;
				break;
			case CTRL_L:
				ctrl_l	= make;
				break;
			case CTRL_R:
				ctrl_r	= make;
				break;
			case ALT_L:
				alt_l	= make;
				break;
			case ALT_R:
				alt_l	= make;
				break;
			case CAPS_LOCK:
				if (make) {
					caps_lock   = !caps_lock;
					set_leds();
				}
				break;
			case NUM_LOCK:
				if (make) {
					num_lock    = !num_lock;
					set_leds();
				}
				break;
			case SCROLL_LOCK:
				if (make) {
					scroll_lock = !scroll_lock;
					set_leds();
				}
				break;
			default:
				break;
			}
		}

		if(make){ /* ignore Break Code */
			t_bool pad = FALSE;

			/* handle the small pad first */
			if ((key >= PAD_SLASH) && (key <= PAD_9)) {
				pad = TRUE;
				switch(key) {	/* '/', '*', '-', '+', and 'Enter' in num pad  */
				case PAD_SLASH:
					key = '/';
					break;
				case PAD_STAR:
					key = '*';
					break;
				case PAD_MINUS:
					key = '-';
					break;
				case PAD_PLUS:
					key = '+';
					break;
				case PAD_ENTER:
					key = ENTER;
					break;
				default:	/* keys whose value depends on the NumLock */
					if (num_lock) {	/* '0' ~ '9' and '.' in num pad */
						if ((key >= PAD_0) && (key <= PAD_9)) {
							key = key - PAD_0 + '0';
						}
						else if (key == PAD_DOT) {
							key = '.';
						}
					}
					else{
						switch(key) {
						case PAD_HOME:
							key = HOME;
							break;
						case PAD_END:
							key = END;
							break;
						case PAD_PAGEUP:
							key = PAGEUP;
							break;
						case PAD_PAGEDOWN:
							key = PAGEDOWN;
							break;
						case PAD_INS:
							key = INSERT;
							break;
						case PAD_UP:
							key = UP;
							break;
						case PAD_DOWN:
							key = DOWN;
							break;
						case PAD_LEFT:
							key = LEFT;
							break;
						case PAD_RIGHT:
							key = RIGHT;
							break;
						case PAD_DOT:
							key = DELETE;
							break;
						default:
							break;
						}
					}
					break;
				}
			}
			key |= shift_l	? FLAG_SHIFT_L	: 0;
			key |= shift_r	? FLAG_SHIFT_R	: 0;
			key |= ctrl_l	? FLAG_CTRL_L	: 0;
			key |= ctrl_r	? FLAG_CTRL_R	: 0;
			key |= alt_l	? FLAG_ALT_L	: 0;
			key |= alt_r	? FLAG_ALT_R	: 0;
			key |= pad	? FLAG_PAD	: 0;

			*pkey = key;
			return TRUE;
		}
	}

	return FALSE;
}

PRIVATE t_8 get_byte_from_kb_buf()
{
	t_8	scan_code;

	RT_ASSERT(kb_in.count>0);
	scan_code = *(kb_in.p_tail);
	kb_in.p_tail++;
	if (kb_in.p_tail == kb_in.buf + KB_IN_BYTES) {
		kb_in.p_tail = kb_in.buf;
	}
	kb_in.count--;

	return scan_code;
}

PRIVATE void kb_wait() /* wait inpit cache of 8042 */
{
	t_8 kb_stat;

	do {
		kb_stat = inb(KB_CMD);
	} while (kb_stat & 0x02);
}

PRIVATE void kb_ack()
{
	t_8 kb_read;

	do {
		kb_read = inb(KB_DATA);
	} while (kb_read != KB_ACK);
}

PRIVATE void set_leds()
{
	t_8 leds = (caps_lock << 2) | (num_lock << 1) | scroll_lock;

	kb_wait();
	outb(KB_DATA, LED_CODE);
	kb_ack();

	kb_wait();
	outb(KB_DATA, leds);
	kb_ack();
}

/**
 * @addtogroup QEMU
 */
/*@{*/

void rt_keyboard_isr(void)
{
	rt_uint8_t data;

	if ((inb(KBSTATP) & KBS_DIB) == 0)
		return ;

	data = inb(KBDATAP);

	if (kb_in.count < KB_IN_BYTES) {
		*(kb_in.p_head) = data;
		kb_in.p_head++;
		if (kb_in.p_head == kb_in.buf + KB_IN_BYTES) {
			kb_in.p_head = kb_in.buf;
		}
		kb_in.count++;
	}
}
/* generally, this should be called in task level for all key inpit support,
but here only support a key that is composed of 2 bytes */
rt_bool_t rt_keyboard_getc(char* c)
{
	if(kb_in.count>=2)
	{
		rt_uint32_t key = 0;
		rt_bool_t rv=keyboard_read(&key);

		switch(key)
		{
			case TAB:
				*c = '\t';
				break;
			case ENTER:
				*c = '\n';
				break;
			case BACKSPACE:
				*c = '\b';
				break;
			default:
				*c = key;
				break;
		}

		return rv;
	}

	return RT_FALSE;
}

/*@}*/