#pragma once

#include <avr/sleep.h>
#include <avr/power.h>
#include <avr/wdt.h>

// Utility macros
#define adc_disable() (ADCSRA &= ~_BV(ADEN)) // disable ADC (before power-off)
#define adc_enable()  (ADCSRA |= _BV(ADEN)) // re-enable ADC
#define enable_pin_interrupts()  (GIMSK |= _BV(PCIE))  // Enable Pin Change Interrupts

class TinyPower {

public:
	static void setup() {
	  set_sleep_mode(SLEEP_MODE_PWR_DOWN);
	  enable_pin_interrupts();
	  enableWdt();
	}

	static void sleep() {
	  PCMSK |= _BV(PCINT0);                   // Use PB0 as interrupt pin
	  adc_disable();

	  sleep_enable();                         // Sets the Sleep Enable bit in the MCUCR Register (SE BIT)
	  sei();                                  // Enable interrupts

	  sleep_cpu();                            // sleep

	  cli();                                  // Disable interrupts
	  PCMSK &= ~_BV(PCINT0);                  // Turn off PB0 as interrupt pin
	  sleep_disable();                        // Clear SE bit
	  adc_enable();

	  sei();                                  // Enable interrupts
	}

	//enable the wdt for 8sec interrupt
	static void enableWdt()
	{
	    MCUSR = 0x00;
	    WDTCR |= _BV(WDCE) | _BV(WDE);
	    WDTCR = _BV(WDIE) | _BV(WDP3) | _BV(WDP0);    //8192ms
	}

	static void disableWdt() {
	  MCUSR = 0x00;
	  WDTCR |= _BV(WDCE) | _BV(WDE);
	  WDTCR = 0x00;
	}
};