#pragma once 

#include <Arduino.h>
#include "pins.h"


#define DEFAULT_DEBOUNCE_TIME 25


#define KEY_1     0x800
#define KEY_2     0x400
#define KEY_3     0x200
#define KEY_4     0x100
#define KEY_5     0x080
#define KEY_6     0x040
#define KEY_7     0x020
#define KEY_8     0x010
#define KEY_9     0x008
#define KEY_STAR  0x004
#define KEY_0     0x002
#define KEY_HASH  0x001


class Keypad {
	protected:
	unsigned int m_mask;
	unsigned int m_debounceTime;
	bool m_debouncing;
	unsigned long m_debounceEnd;
	bool m_pressed;

	static Keypad buttons[12];

	void startDebounce() {
		m_debouncing = true;
		m_debounceEnd = millis() + m_debounceTime;
	}

	public:
	static unsigned int state;
	static void Setup() {
		pinMode(LED, OUTPUT);

		pinMode(COL_1, INPUT_PULLUP);
		pinMode(COL_2, INPUT_PULLUP);
		pinMode(COL_3, INPUT_PULLUP);
	
		pinMode(ROW_1, INPUT_PULLUP);
		pinMode(ROW_2, INPUT_PULLUP);
		pinMode(ROW_3, INPUT_PULLUP);
		pinMode(ROW_4, INPUT_PULLUP);
	}

	static void Update() {
		byte col1 = 1 - digitalRead(COL_1);	
		byte col2 = 1 - digitalRead(COL_2);	
		byte col3 = 1 - digitalRead(COL_3);	
	
		byte row1 = 1 - digitalRead(ROW_1);
		byte row2 = 1 - digitalRead(ROW_2);
		byte row3 = 1 - digitalRead(ROW_3);
		byte row4 = 1 - digitalRead(ROW_4);
	
		#define BUILD_ROW(row, c1, c2, c3) \
			( ((row & c1) << 2) | ((row & c2) << 1) | (row & c3) )
	
		byte row1_buttons = BUILD_ROW(row1, col1, col2, col3);
		byte row2_buttons = BUILD_ROW(row2, col1, col2, col3);
		byte row3_buttons = BUILD_ROW(row3, col1, col2, col3);
		byte row4_buttons = BUILD_ROW(row4, col1, col2, col3);
	
		unsigned int pins  = 0 | 
			(row1_buttons << 9) | 
			(row2_buttons << 6) | 
			(row3_buttons << 3) | 
			(row4_buttons << 0);
	
		for (int i=0; i<12; i++) {
			buttons[i].update(pins);
		}
	}

	Keypad(unsigned int index, unsigned int debounceTime=DEFAULT_DEBOUNCE_TIME) {
		m_mask = 1 << index;
		m_debounceTime = debounceTime;
		m_debouncing = false;
		m_pressed = false;
	}

	void update(unsigned int pins) {
		if (m_debouncing) {
			if (millis() > m_debounceEnd) {
				/* done debouncing, continue */
				m_debouncing = false;
			}
			else {
				/* still debouncing, ignore changes */
				return;
			}
		}
		
		if ((m_mask & pins)) {
			/* pressed */
			if (m_pressed) {
				/* already marked */
			}
			else {
				/* update state */
				m_pressed = true;
				state = state | m_mask;
				startDebounce();
			}
		}
		else {
			/* released */
			if (!m_pressed) {
				/* already marked, ignore */
			}
			else {
				/* update state */
				m_pressed = false;
				state = state & ~m_mask;
				startDebounce();
			}
		}
	}
};
unsigned int Keypad::state = 0;

Keypad Keypad::buttons[12] = {
	Keypad(0),
	Keypad(1),
	Keypad(2),
	Keypad(3),
	Keypad(4),
	Keypad(5),
	Keypad(6),
	Keypad(7),
	Keypad(8),
	Keypad(9),
	Keypad(10),
	Keypad(11),
};