/*
  Analog Input to LED and to Serial

  Demonstrates analog input by reading an analog sensor (LDR) on analog pin 0, 
  sending its value over Software Serial and
  turning on and off a light emitting diode(LED) connected to digital pin 7.
  The amount of time the LED will be on and off depends on the value obtained
  by analogRead().
  This code is optimised for usage with the ATTiny44A

  created by David Cuartielles
  modified 30 Aug 2011
  By Tom Igoe
  modified 12 Mar 2019
  by Joey van der Bie

  This example code is in the public domain.

  http://www.arduino.cc/en/Tutorial/AnalogInput
*/
#include <SoftwareSerial.h>
#define RX    1   
#define TX    0   

const int LDR_PIN = A2;    // select the input pin for the LDR
const int LED_PIN = 7;     // select the pin for the LED
const int BUTTON_PIN = 3;     // the number of the pushbutton pin

int sensorValue = 0;              // variable to store the value coming from the sensor
int ledState = LOW;               // ledState used to set the LED
int buttonPushCounter = 0;   // counter for the number of button presses
int buttonState = 0;         // current state of the button
int lastButtonState = 0;     // previous state of the button
int interval = 1000;              // variable for delay to turn led on/off
unsigned long previousMillis = 0; // will store last time LED was updated

SoftwareSerial Serial(RX, TX);

void setup() {
  //Start serial 
  Serial.begin(9600);
  Serial.println("Initializing...");

  // declare the LED pin as an OUTPUT:
  pinMode(LED_PIN, OUTPUT);
  // declare the LDR pin as an INPUT
  pinMode(LDR_PIN, INPUT);
  //configure pin 3 as an input and enable the internal pull-up resistor
  pinMode(BUTTON_PIN, INPUT_PULLUP);
}

void loop() {
    // read the state of the pushbutton value:
   buttonState = digitalRead(BUTTON_PIN);
  // compare the buttonState to its previous state
  if (buttonState != lastButtonState) {
    // if the state has changed, increment the counter
    if (buttonState == HIGH) {
      // if the current state is HIGH then the button went from off to on:
      // increase the button counter but stop at the max states of 2
      buttonPushCounter = (buttonPushCounter + 1 ) % 2;
      
      Serial.print("number of button pushes: ");
      Serial.println(buttonPushCounter);

      // Give feedfack to the user via the LED
      
         digitalWrite(LED_PIN, LOW);         
         delay(50);
         digitalWrite(LED_PIN, HIGH);
         delay(50);
         digitalWrite(LED_PIN, LOW);
         delay(50);
         digitalWrite(LED_PIN, ledState);
    } else {
      // if the current state is LOW then the button went from on to off:
//      Serial.println("off");
    }
  }
  // save the current state as the last state, for next time through the loop
  lastButtonState = buttonState;

  
  // read the value from the sensor:
  sensorValue = analogRead(LDR_PIN);
  
  // map the value to a broader range to compensate for small difference in the LDR
//  sensorValue = map(sensorValue, 900, 1023, 0, 1023);

//  //Send the value over the Serial line to the computer
//  Serial.println(sensorValue);

  if(buttonPushCounter == 1){
    //Store sensor value as interval for LED
    interval = sensorValue;
  }else{
    // use default LED interval
    interval = 500;
  }

  // check to see if it's time to blink the LED; that is, if the difference
  // between the current time and last time you blinked the LED is bigger than
  // the interval at which you want to blink the LED.
  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {
    // save the last time you blinked the LED
    previousMillis = currentMillis;

    // if the LED is off turn it on and vice-versa:
    if (ledState == LOW) {
      ledState = HIGH;
    } else {
      ledState = LOW;
    }

    // set the LED with the ledState of the variable:
    digitalWrite(LED_PIN, ledState);
  }
}