// keyboard.c
// Author: Josh Holtrop
// Created: 04/17/03
// Modified: 08/16/04

#include "hos_defines.h"
#include "char/keyboard.h"
#include "sys/io.h"			// inportb, outportb
#include "functions.h"
#include "lang/conv.h"			// asciiSwitchCase()

#include "kout.h"
#include "display.h"			// display_activate()

#define KBD_BUFFER_LENGTH 64

u8_t	kbdFlags = 0;			// holds current keyboard flags - caps/num/scroll/shift/ctrl/alt
u8_t	lastWasE0 = 0;			// was the last byte 0x0E ?
u32_t	kbdBuffer[KBD_BUFFER_LENGTH];	// a buffer for all keypresses
int	kbdBufferStart = 0;		// position of next key in buffer
int	kbdBufferLen = 0;		// number of keys left in the buffer
u8_t	rawIgnore = 0;			// how many signals to blatantly ignore
u8_t	ackReason = 0;			// used to record the reason why we would get an acknowledge byte (0xFA)


//these arrays convert a keyboard scan code to an ASCII character value
const u8_t SCAN2ASCII[129] =		// for normal keys
	"\000\0331234567890-=\010\011"	// null,esc,1234567890-=,bksp,tab
	"qwertyuiop[]\n\000as"		// qwertyuiop[],enter,lctrl,as
	"dfghjkl;'`\000\\zxcv"		// dfghjkl;'`,lshift,\zxcv
	"bnm,./\000*\000 \000\000\000\000\000\000"	// bnm,./,rshift,*,alt,space,caps,f1,f2,f3,f4,f5
	"\000\000\000\000\000\000\000\000\000\000-\000\000\000+\000"		// f6,f7,f8,f9,f10,num,scrl,home,up,pgup,dash,left,center,right,plus,end
	"\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"	// down,pgdn,ins,del,?,?,?,f11,f12,?,?,winL,winR,menu,?,?
	"\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"	// ?
	"\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000";	// ?
const u8_t SCAN2ASCII2[129] =		// for shifted or numlocked keys
	"\000\033!@#$%^&*()_+\010\011"	// null,esc,!@#$%^&*()_+,bksp,tab
	"QWERTYUIOP{}\n\000AS"		// QWERTYUIOP{},enter,lctrl,AS
	"DFGHJKL:\"~\000|ZXCV"		// DFGHJKL:"~,lshift,|ZXCV
	"BNM<>?\000*\000 \000\000\000\000\000\000"	// BNM<>?,rshift,*,alt,space,caps,f1,f2,f3,f4,f5
	"\000\000\000\000\000\000\000789-456+1"		// f6,f7,f8,f9,f10,num,scrl,789-456+1
	"230.\000\000\000\000\000\000\000\000\000\000\000\000"			// 230.,?,?,?,f11,f12,?,?,winL,winR,menu,?,?
	"\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000"	// ?
	"\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000";	// ?

// The Keyboard Interrupt Service Routine
void isr_keyboard()
{
	u8_t kbdScan = inportb(0x60);
	u8_t inState = inportb(0x61);
	outportb(0x61, inState|0x80);
	outportb(0x61, inState);
	
	if (kbdScan == 0xFA)	//250				// ACKnowledge
	{
		//printf("KBD_ACK 0x%x!\n", ackReason);
		switch (ackReason)
		{
		case 0xED:					// reset LEDs
			outportb(0x60, (kbdFlags & 0x07));
			break;
		}
		ackReason = 0;
	}
	if (rawIgnore)						// ignore keycodes
	{
		rawIgnore--;
		return;
	}
	if (lastWasE0 && (kbdScan == 0x2A || kbdScan == 0xAA))	// ignore extended "shift"
	{
		lastWasE0 = 0;
		return;
	}
	if (kbdScan == 0xE0)					// 0xE0 == extended key
	{
		lastWasE0 = 1;
		return;
	}
	if (kbdScan == 0xE1)					// 0xE1 == 2nd-set-extended key
	{
		rawIgnore = 2;
		return;
	}
	

	switch (kbdScan)					// handle control keys
	{
	case KBD_SCAN_LSHIFT:
		kbdFlags |= KBDF_SHIFT;
		break;
	case KBD_SCAN_RSHIFT:
		kbdFlags |= KBDF_SHIFT;
		break;
	case KBD_SCAN_CTRL:
		kbdFlags |= KBDF_CTRL;
		break;
	case KBD_SCAN_ALT:
		kbdFlags |= KBDF_ALT;			
		break;

	case KBD_SCAN_LSHIFT + KBD_SCAN_RELEASED:
		kbdFlags &= (KBDF_SHIFT ^ 0xFF);
		break;
	case KBD_SCAN_RSHIFT + KBD_SCAN_RELEASED:
		kbdFlags &= (KBDF_SHIFT ^ 0xFF);
		break;
	case KBD_SCAN_CTRL + KBD_SCAN_RELEASED:
		kbdFlags &= (KBDF_CTRL ^ 0xFF);
		break;
	case KBD_SCAN_ALT + KBD_SCAN_RELEASED:
		kbdFlags &= (KBDF_ALT ^ 0xFF);
		break;
	case KBD_SCAN_CAPS+KBD_SCAN_RELEASED:
		kbdFlags ^= KBDF_CAPS;
		kbd_resetLEDs();				// update LEDs
		break;
	case KBD_SCAN_SCROLL+KBD_SCAN_RELEASED:
		kbdFlags ^= KBDF_SCROLL;
		kbd_resetLEDs();				// update LEDs
		break;
	case KBD_SCAN_NUM+KBD_SCAN_RELEASED:
		kbdFlags ^= KBDF_NUM;
		kbd_resetLEDs();				// update LEDs
		break;
	}
	u8_t kbdAscii;
		// shift or (numlock and key from numpad)
	if ( (kbdFlags & KBDF_SHIFT) || ((kbdFlags & KBDF_NUM) && (kbdScan >= 71) && (kbdScan <= 83)) )
		kbdAscii = SCAN2ASCII2[kbdScan & 0x7F];
	else	// normal key
		kbdAscii = SCAN2ASCII[kbdScan & 0x7F];
	if (kbdFlags & KBDF_CAPS)
		kbdAscii = asciiSwitchCase(kbdAscii);		// won't affect non-letter characters

//====do something with key::
//	kprintf("kbdScan = \e[31;1m0x%x\e[0m\tkbdAscii = \e[1;32m0x%x\e[0m (\e[35m%c\e[0m)\tkbdFlags = \e[34m0x%x\e[0m\n", kbdScan, kbdAscii, kbdAscii, kbdFlags);
	if ((kbdScan == 83) && (kbdFlags & KBDF_CTRL) && (kbdFlags & KBDF_ALT))
	{
		kprintf("Initiating reboot.");
		restart();
	}
	if (kbdScan & KBD_SCAN_RELEASED)
		kbdAscii = 0;
	if (kbdBufferLen < KBD_BUFFER_LENGTH)			//no key slots available
		kbdBuffer[(kbdBufferStart+kbdBufferLen++)%KBD_BUFFER_LENGTH] = (u32_t) ((kbdFlags << 16) | (kbdScan << 8) | kbdAscii);


	if (kbdAscii)
		kprintf("%c", kbdAscii);
//	if (kbdFlags & KBDF_ALT)
//	  {
	    if (kbdScan >= 0x3B && kbdScan <= 0x44)
	      display_activate(kbdScan - 0x3B);
	    if (kbdScan >= 0x57 && kbdScan <= 0x58)
	      display_activate(kbdScan - 0x4D);
//	  }
}

//Gets a key from the buffer, returns 0 if no keys available, returns immediately
u32_t kbdGetKey()
{
	if (kbdBufferLen == 0)					// buffer empty
		return 0;
	u32_t retVal = kbdBuffer[kbdBufferStart];
	kbdBufferStart++;
	kbdBufferLen--;
	if (kbdBufferStart >= KBD_BUFFER_LENGTH)
		kbdBufferStart = 0;
	return retVal;
}

//Gets a key from the buffer, if no keys available, waits for one to be entered
u32_t kbdWaitKey()
{
	for (;;)
	{
		if (kbdBufferLen != 0)				// buffer empty
			break;
	}		
	u32_t retVal = kbdBuffer[kbdBufferStart];
	kbdBufferStart++;
	kbdBufferLen--;
	if (kbdBufferStart >= KBD_BUFFER_LENGTH)
		kbdBufferStart = 0;
	return retVal;
}

//Resets the keyboard LEDs to reflect the current state of the num lock, caps lock, and scroll lock bits
void	kbd_resetLEDs()
{
	outportb(0x60, 0xED);
	ackReason = 0xED;
}