//https://docs.wokwi.com/parts/wokwi-attiny85   simulate ATTINY85 on wokwi
//https://wokwi.com/projects/317140124437578305  get interrupts working
//https://www.arduino.cc/reference/en/language/functions/time/millis/  millis() in arduinoland.
// https://wokwi.com/projects/318885209198035539  debounce function.
// https://www.gadgetronicx.com/attiny85-external-pin-change-interrupt/ datasheet attiny85 ints.
//https://electronics.stackexchange.com/questions/264434/attiny85-interrupt-confusion "only PB2 on attiny85 can be used to trap edge changes"
#include <TinyDebug.h>
#include <avr/io.h>
#include <avr/interrupt.h>


#define clockin PB2    //use digital I/O pin PB1 (pin 6 of IC) for input
#define INT0_VECTOR INT0_vect 
#define LED PB0
#define POT A3
#define TRIGGER_TIME_WANTED_PIN A2  
volatile byte x = 0;
byte oldx = 0;
int timer; // for outputting trigger of timer ms.

int potValue = 0; //the right pot sets MODE for the MCU
int triggerValue = 0;  // the left pot traps time of trigger (MS)


void setup() {
    pinMode(clockin, INPUT_PULLUP);   // Set our interrupt pin as input with a pullup   
    pinMode(LED, OUTPUT);  //PB0 is GPIO output
    
     

    cli();                            // Disable interrupts during setup
 
    PCMSK = 0b00000100;  //enable PB2/PCINT2 as our interrupt pin.

    GIMSK = 0b01000000;  // enable ext pin interrupts; enable pin changes to be treated as interrupts.
    
    MCUCR = 0b00000010; // int rising fall only. In wiwok unclick "bounce" DEFAULT

  
    sei();      
    Debug.begin();  
  //Debug.println("you are beginning the sketch");
 
 
}

void loop() {

//read pot value -- what mode are we in. 
potValue = analogRead(POT);


 //display value and light LED when pot is < 901

  if (x != oldx){
      oldx = x;

      if (potValue < 901){
        Debug.println(x);
        digitalWrite(LED, x % 2);
      }

      if (potValue >=901){
         
        MCUCR = 0b00000010; // Interrupt on falling edge only.
        timer = analogRead(TRIGGER_TIME_WANTED_PIN);
        digitalWrite(LED,LOW); //Turn LED off in case its on from previous
        digitalWrite(LED,HIGH); //Turn LED on
        Debug.println(x);
        delay(timer);
        digitalWrite(LED,LOW); //Turn LED off
      }
      
      if (x == 4) {
        x = 0;
      }


  } //end main if.
  
//trap values of pot and do things.

//Debug.print("Value of pot is: ");
//Debug.println(potValue);

  if (potValue < 300) {
    MCUCR = 0b00000011; // Interrupt on rising edge only.  
    }

  if (potValue >= 301 && potValue < 500) {
    MCUCR = 0b00000010; // Interrupt on falling edge only.
    }
  
    if ((potValue > 501) && (potValue < 901)) {
    MCUCR = 0b00000001; // Interrupt on change.
    }


} //end main loop.

ISR(INT0_VECTOR) {
             
      x++;
 
}