/* Copyright (C) 2011 by Jacob Alexander
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <avr/io.h>
#include <avr/pgmspace.h>
#include <avr/interrupt.h>
#include <util/delay.h>
//#include "usb_keyboard.h"

// TEMP INCLUDES
#include "usb_keyboard_debug.h"
#include <print.h>

#define CPU_PRESCALE(n)	(CLKPR = 0x80, CLKPR = (n))

// Sleep defined in milliseconds


// Number of keys
#define KEYBOARD_SIZE 63
#define KEYPAD_SIZE 16


// Debouncing Defines
#define SAMPLE_THRESHOLD 100
#define MAX_SAMPLES 127 // Max is 127, reaching 128 is very bad


// Verified Keypress Defines
#define USB_TRANSFER_DIVIDER 10 // 1024 == 1 Send of keypresses per second, 1 == 1 Send of keypresses per ~1 millisecond


// Drive Pin Defines
#define DRIVE_reg_1 PORTD
#define DRIVE_reg_2 PORTD
#define DRIVE_reg_3 PORTD
#define DRIVE_reg_4 PORTD
#define DRIVE_reg_5 PORTD
#define DRIVE_reg_6 PORTD
#define DRIVE_reg_7 PORTE
#define DRIVE_reg_8 PORTE
#define DRIVE_reg_9 PORTE
#define DRIVE_reg_10 <blank>
#define DRIVE_reg_11 <blank>
#define DRIVE_reg_12 <blank>

#define DRIVE_pin_1 2
#define DRIVE_pin_2 3
#define DRIVE_pin_3 4
#define DRIVE_pin_4 5
#define DRIVE_pin_5 6
#define DRIVE_pin_6 7
#define DRIVE_pin_7 0
#define DRIVE_pin_8 1
#define DRIVE_pin_9 6
#define DRIVE_pin_10 <blank>
#define DRIVE_pin_11 <blank>
#define DRIVE_pin_12 <blank>

// Detect Pin/Group Defines
#define DETECT_group_1 1
#define DETECT_group_2 2
#define DETECT_group_3 3
#define DETECT_group_4 4
#define DETECT_group_5 5
#define DETECT_group_6 6
#define DETECT_group_7 7
#define DETECT_group_8 8
#define DETECT_group_9 9
#define DETECT_group_10 <blank>
#define DETECT_group_11 <blank>
#define DETECT_group_12 <blank>

#define DETECT_group_size_1 7
#define DETECT_group_size_2 7
#define DETECT_group_size_3 6
#define DETECT_group_size_4 8
#define DETECT_group_size_5 7
#define DETECT_group_size_6 7
#define DETECT_group_size_7 8
#define DETECT_group_size_8 8
#define DETECT_group_size_9 4
#define DETECT_group_size_10 <blank>
#define DETECT_group_size_11 <blank>
#define DETECT_group_size_12 <blank>

/*
#define DETECT_group_array_1 {{KEY_ESC,KEY_CTRL,KEY_CAPS_LOCK,KEY_SHIFT},{0,1,0,1}}
#define DETECT_group_array_2 {{KEY_BACKSPACE,KEY_UP,KEY_DOWN,KEY_A,KEY_INSERT,KEY_ALT,KEY_Z,KEY_RIGHT},{0,0,0,0,0,1,0,0}}
#define DETECT_group_array_3 {{KEY_TILDE,KEY_DELETE,KEY_LEFT,KEY_SPACE,KEY_X,KEY_S,KEY_TAB,KEY_1},{0,0,0,0,0,0,0,0}}
#define DETECT_group_array_4 {{KEY_SLASH,KEY_RIGHT_BRACE,KEY_ENTER,KEY_D,KEY_2,KEY_Q,KEY_C},{0,0,0,0,0,0,0}}
#define DETECT_group_array_5 {{KEY_EQUAL,KEY_LEFT_BRACE,KEY_QUOTE,KEY_F,KEY_3,KEY_W,KEY_V},{0,0,0,0,0,0,0}}
#define DETECT_group_array_6 {{KEY_MINUS,KEY_P,KEY_SEMICOLON,KEY_G,KEY_4,KEY_E,KEY_B,KEY_BACKSLASH},{0,0,0,0,0,0,0,0}}
#define DETECT_group_array_7 {{KEY_8,KEY_U,KEY_K,KEY_7,KEY_Y,KEY_COMMA},{0,0,0,0,0,0}}
#define DETECT_group_array_8 {{KEY_9,KEY_I,KEY_PERIOD,KEY_J,KEY_6,KEY_T,KEY_M},{0,0,0,0,0,0,0}}
#define DETECT_group_array_9 {{KEY_0,KEY_O,KEY_L,KEY_H,KEY_5,KEY_R,KEY_N},{0,0,0,0,0,0,0}}
*/
// Switch Codes
#define DETECT_group_array_1 {55,22,6 ,40,43,27,11}
#define DETECT_group_array_2 {56,23,7 ,41,58,26,10}
#define DETECT_group_array_3 {57,24,8 ,42,25,9}
#define DETECT_group_array_4 {54,21,5 ,39,44,28,12,59}
#define DETECT_group_array_5 {53,20,4 ,38,45,29,13}
#define DETECT_group_array_6 {52,19,3 ,37,46,30,14}
#define DETECT_group_array_7 {51,18,2 ,36,61,31,15,63}
#define DETECT_group_array_8 {50,17,1 ,35,47,32,16,62}
#define DETECT_group_array_9 {48,49,33,34} // 49/60 are the same line
#define DETECT_group_array_10 <blank>
#define DETECT_group_array_11 <blank>
#define DETECT_group_array_12 <blank>



// Drive Macros (Generally don't need to be changed), except for maybe DRIVE_DETECT
#define DRIVE_DETECT(reg,pin,group) \
			reg &= ~(1 << pin); \
			detection(group); \
			reg |= (1 << pin);

#define DD_CASE(number) \
			case number:\
				DRIVE_DETECT(DRIVE_reg_##number, DRIVE_pin_##number, DETECT_group_##number)

#define DD_CASE_ORD(number) \
			DD_CASE(number) \
			break;

#define DD_CASE_END(number,var) \
			DD_CASE(number) \
			var = -1; \
			break;


// Updates the current detection sample and last sample bit
// Detection Macros (Probably don't need to be changed, but depending the matrix, may have to be)
// Determine if key is either normal or a modifier
#define DET_GROUP_CHECK(index,test) \
			if ( test ) { \
				keyDetectArray[groupArray[index]]++; \
			}


// XXX - Detection Groups
// Checks each of the specified pins, and then if press detected, determine if the key is normal or a modifier
// Inverse logic applies for the PINs

// Used for 1 detection group (Special group)
#define DET_GROUP_1 \
			DET_GROUP_CHECK(0,!( PINB & (1 << 7) )) \
			DET_GROUP_CHECK(1,!( PINC & (1 << 0) )) \
			DET_GROUP_CHECK(2,!( PIND & (1 << 0) )) \
			DET_GROUP_CHECK(3,!( PIND & (1 << 1) )) \

// Used for 4 detection groups (Skips J1 P9)
#define DET_GROUP_2 \
			DET_GROUP_CHECK(0,!( PINE & (1 << 7) )) \
			DET_GROUP_CHECK(1,!( PINB & (1 << 0) )) \
			DET_GROUP_CHECK(2,!( PINB & (1 << 1) )) \
			DET_GROUP_CHECK(3,!( PINB & (1 << 2) )) \
			DET_GROUP_CHECK(4,!( PINB & (1 << 3) )) \
			DET_GROUP_CHECK(5,!( PINB & (1 << 4) )) \
			DET_GROUP_CHECK(6,!( PINB & (1 << 5) )) \

// Used for 1 detection group (Skips J1 P6 and J1 P9)
#define DET_GROUP_3 \
			DET_GROUP_CHECK(0,!( PINE & (1 << 7) )) \
			DET_GROUP_CHECK(1,!( PINB & (1 << 0) )) \
			DET_GROUP_CHECK(2,!( PINB & (1 << 1) )) \
			DET_GROUP_CHECK(3,!( PINB & (1 << 2) )) \
			DET_GROUP_CHECK(4,!( PINB & (1 << 4) )) \
			DET_GROUP_CHECK(5,!( PINB & (1 << 5) )) \

// Used for 3 detection groups (No skips, except special group 1)
#define DET_GROUP_4 \
			DET_GROUP_CHECK(0,!( PINE & (1 << 7) )) \
			DET_GROUP_CHECK(1,!( PINB & (1 << 0) )) \
			DET_GROUP_CHECK(2,!( PINB & (1 << 1) )) \
			DET_GROUP_CHECK(3,!( PINB & (1 << 2) )) \
			DET_GROUP_CHECK(4,!( PINB & (1 << 3) )) \
			DET_GROUP_CHECK(5,!( PINB & (1 << 4) )) \
			DET_GROUP_CHECK(6,!( PINB & (1 << 5) )) \
			DET_GROUP_CHECK(7,!( PINB & (1 << 6) )) \

// Combines the DET_GROUP_Xs above for the given groupArray
#define DET_GROUP(group,det_group) \
			case group: \
				{ \
					uint8_t groupArray[DETECT_group_size_##group] = DETECT_group_array_##group; \
					_delay_us(1); \
					DET_GROUP_##det_group \
				} \
				break;


// Loop over all of the sampled keys of the given array
// If the number of samples is higher than the sample threshold, flag the high bit, clear otherwise
// This should be resetting VERY quickly, cutting off a potentially valid keypress is not an issue
#define DEBOUNCE_ASSESS(table,size) \
			for ( uint8_t key = 1; key < size + 1; key++ ) {\
				table[key] = ( table[key] & ~(1 << 7) ) > SAMPLE_THRESHOLD ? (1 << 7) : 0x00; \
			} \


// NOTE: Highest Bit: Valid keypress (0x80 is valid keypress)
//        Other Bits: Pressed state sample counter
uint8_t keyDetectArray[KEYBOARD_SIZE + 1];
uint8_t keypadDetectArray[KEYPAD_SIZE + 1];

uint16_t sendKeypressCounter = 0;
volatile uint8_t sendKeypresses = 0;

static const uint8_t defaultMap[] = { 0,
				KEY_INSERT,
				KEY_1,
				KEY_2,
				KEY_3,
				KEY_4,
				KEY_5,
				KEY_6,
				KEY_7,
				KEY_8,
				KEY_9,
				KEY_0,
				KEY_MINUS,
				KEY_EQUAL,
				KEY_BACKSLASH,
				KEY_ALT,
				KEY_TAB,
				KEY_Q,
				KEY_W,
				KEY_E,
				KEY_R,
				KEY_T,
				KEY_Y,
				KEY_U,
				KEY_I,
				KEY_O,
				KEY_P,
				KEY_LEFT_BRACE,
				KEY_RIGHT_BRACE,
				KEY_DELETE,
				KEY_UP,
				KEY_CTRL,
				KEY_CAPS_LOCK,
				KEY_A,
				KEY_S,
				KEY_D,
				KEY_F,
				KEY_G,
				KEY_H,
				KEY_J,
				KEY_K,
				KEY_L,
				KEY_SEMICOLON,
				KEY_QUOTE,
				KEY_ENTER,
				KEY_DOWN,
				KEY_ESC,
				KEY_LEFT_SHIFT,
				KEY_Z,
				KEY_X,
				KEY_C,
				KEY_V,
				KEY_B,
				KEY_N,
				KEY_M,
				KEY_COMMA,
				KEY_PERIOD,
				KEY_SLASH,
				KEY_RIGHT_SHIFT,
				KEY_LEFT,
				KEY_RIGHT,
				KEY_SPACE };

// Scan Code Decoder (for debug)
void printDecodeScancode( int code )
{

	static const char* decodeArray[] = { "", "", "", "", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "1", "2", "3", "4", "5", "6", "7", "8", "9", "0", "Enter", "Esc", "Backspace", "Tab", "Space", "-_", "=+", "[{", "]}", "\\", "#", ";:", "'\"", "`~", ",<", ".>", "/?", "Caps Lock", "F1", "F2", "F3", "F4", "F5", "F6", "F7", "F8", "F9", "F10", "F11", "F12", "Print Screen", "Scroll Lock", "Pause", "Insert", "Home", "Page Up", "Delete", "End", "Page Down", "Right", "Left", "Down", "Up", "Num Lock", "K1", "K2", "K3", "K4", "K5", "K6", "K7", "K8", "K9", "K0", "K." };
	print_P( decodeArray[ defaultMap[code] ] );
}

void detection( int group )
{
	// XXX Modify for different detection groups <-> groupArray mappings
	switch ( group ) {
		DET_GROUP(1,2)
		DET_GROUP(2,2)
		DET_GROUP(3,3)
		DET_GROUP(4,4)
		DET_GROUP(5,2)
		DET_GROUP(6,2)
		DET_GROUP(7,4)
		DET_GROUP(8,4)
		DET_GROUP(9,1)
	}
}



// XXX This part is configurable
inline void pinSetup(void)
{
	// For each pin, 0=input, 1=output
	DDRA = 0x00;
	DDRB = 0x00;
	DDRC = 0x00;
	DDRD = 0xFC;
	DDRE = 0x43;
	DDRF = 0x00;


	// Setting pins to either high or pull-up resistor
	PORTA = 0xFF;
	PORTB = 0xFF;
	PORTC = 0x01;
	PORTD = 0xFF;
	PORTE = 0xC3;
	PORTF = 0xFF;
}

int main( void )
{
	// Setup with 16 MHz clock
	CPU_PRESCALE( 0 );

	// Configuring Pins
	pinSetup();

	// Initialize the USB, and then wait for the host to set configuration.
	// If the Teensy is powered without a PC connected to the USB port,
	// this will wait forever.
	usb_init();
	while ( !usb_configured() ) /* wait */ ;

	// Wait an extra second for the PC's operating system to load drivers
	// and do whatever it does to actually be ready for input
	_delay_ms(1000);

	// Setup ISR Timer for flagging a kepress send to USB
	// Set to 256 * 1024 (8 bit timer with Clock/1024 prescalar) timer
	// 
	TCCR0A = 0x00;
	TCCR0B = 0x03;
	TIMSK0 = (1 << TOIE0);

	// Main Detection Loop
	int8_t group = 1;
	uint8_t count = 0;
	for ( ;;group++ ) {
		// XXX Change number of ORDs if number of lines (RowsxColumns) differ
		// Determine which keys are being pressed
		switch ( group ) {
			DD_CASE_ORD(1)
			DD_CASE_ORD(2)
			DD_CASE_ORD(3)
			DD_CASE_ORD(4)
			DD_CASE_ORD(5)
			DD_CASE_ORD(6)
			DD_CASE_ORD(7)
			DD_CASE_ORD(8)
			DD_CASE_END(9,group)
		}

		// Check all Keyboard keys first
		if ( group != -1 )
			continue;

		// Check Keypad keys
		// TODO

		// Check count to see if the sample threshold may have been reached, otherwise collect more data
		count++;
		if ( count < MAX_SAMPLES )
			continue;

		// Reset Sample Counter
		count = 0;

		// Assess debouncing sample table
		DEBOUNCE_ASSESS(keyDetectArray,KEYBOARD_SIZE)
		//DEBOUNCE_ASSESS(keypadDetectArray,KEYPAD_SIZE)

		// Send keypresses over USB if the ISR has signalled that it's time
		if ( !sendKeypresses )
			continue;


		// Detect Valid Keypresses - TODO
		uint8_t validKeys = 0;
		for ( uint8_t key = 0; key < KEYBOARD_SIZE + 1; key++ ) {
			//phex(keyDetectArray[key]);
			//print ("|");
			if ( keyDetectArray[key] & (1 << 7) ) {
				//print("0x");
				//phex( key );
				pint8( key );
				print(" ");

				// Too many keys
				if ( validKeys == 6 )
					break;
				keyboard_keys[validKeys++] = defaultMap[key];
			}
		}
		print(":\n");

		// TODO undo potentially old keys
		for ( uint8_t c = validKeys; c < 6; c++ )
			keyboard_keys[c] = 0;


		// Debugging Output
		//phex(PINA);
		//phex(PINF);
		//print("\n");



		// Print out the current keys pressed
		/*
		if ( keyDetectCount > 0 ) {
			print("Switch: ");
			for ( int c = 0; c < keyDetectCount; c++ ) {
				print("0x");
				phex( keyDetectArray[c] );
				print("|");
				//printDecodeScancode( keyDetectArray[c] );
				print(" ");

			}
			print("\n");
		}
		if ( modifiers ) {
			print("Modifiers: ");
			phex( modifiers );
			print("\n");
		}
		*/

		// After going through each of the key groups, send the detected keys and modifiers
		// Currently limited to the USB spec (6 keys + modifiers)
		// Making sure to pass zeros when there are no keys being pressed
		/*
		for ( int c = 0; c < 6 && c < keyDetectCount; c++ )
			keyboard_keys[c] = c < keyDetectCount ? keyDetectArray[c] : 0;

		// Modifiers
		keyboard_modifier_keys = modifiers;
		*/

		// Send keypresses
		usb_keyboard_send();

		// Clear sendKeypresses Flag
		sendKeypresses = 0;
	}

	// usb_keyboard_press(KEY_B, KEY_SHIFT);
	return 0;
}

ISR( TIMER0_OVF_vect )
{
	sendKeypressCounter++;
	if ( sendKeypressCounter > USB_TRANSFER_DIVIDER ) {
		sendKeypressCounter = 0;
		sendKeypresses = 1;
	}
}