/*
   Project: Four digit 7 segment counter
   Description: Basic counter sketch
   Creation date: 09/20/22
   Author: AnonEngineering

   https://wokwi.com/projects/343741010016207442

   License: Beerware

*/

const int knobPin = A0; // Pot pin, brightness via PWM on the 74HC595 OE pin
const int clockPin = 4;	// Clock pin of 74HC595 is connected to Digital pin 4
const int dataPin = 7;	// Data pin of 74HC595 is connected to Digital pin 7
const int enablePin = 6; // Enable pin of 74HC595 is connected to PWM pin 6
const int latchPin = 5;	// Latch pin of 74HC595 is connected to Digital pin 5

byte leds = 0;		// Variable to hold the pattern of which LEDs are currently turned on or off

void setup()  {
  Serial.begin(9600);
  // Set control pins of 74HC595 as OUTPUT
  pinMode(dataPin, OUTPUT);
  pinMode(latchPin, OUTPUT);
  pinMode(clockPin, OUTPUT);
  pinMode(enablePin, OUTPUT);
  // Set digit pins as OUTPUT / LOW
  for(int i = 8; i <= 11; i++) {
    pinMode(i, OUTPUT);
    digitalWrite(i, LOW);
  }
}

void loop() {

  int pwmValue = analogRead(knobPin);
  int mappedVal = map(pwmValue, 0, 1023, 0, 255);
  Serial.println(mappedVal);
  analogWrite(enablePin, mappedVal);

  leds = 0;	// Initially turns all the LEDs off, by giving the variable 'leds' the value 0
  updateShiftRegister();
  delay(50);

  for (int i = 7; i >= 0; i--)	// Turn all the LEDs ON one by one.
  {
    bitSet(leds, i);		// Set the bit that controls that LED in the variable 'leds'
    updateShiftRegister();
    delay(250);
  }
}

// Toggle Latch, shift bits in leds, toggle back
void updateShiftRegister()  {
   digitalWrite(latchPin, LOW);
   shiftOut(dataPin, clockPin, LSBFIRST, leds);
   digitalWrite(latchPin, HIGH);
}

/*
void showDigits(int value)  {
  int digitsToDisplay = 0;

  // Leading zero suppression, not great..
  if(value < 10) {
    digitsToDisplay = 0;
  } else if(value < 100) {
    digitsToDisplay = 1;
  } else if(value < 1000) {
    digitsToDisplay = 2;
  } else {
    digitsToDisplay = 3;
  }

  for(int digit = digitsToDisplay; digit >= 0; digit--)  { // High digits first, higher power first
    driveSegments(int(value/pow(10, digit)) % 10);  // setup segment pins
    if (digit == dpPos) digitalWrite(DP_PIN, LOW);  // turn on DP?
    digitalWrite(DIGIT_PINS[digit], HIGH);          // turn digit on
    digitalWrite(DIGIT_PINS[digit], LOW);           // turn digit & DP off
    digitalWrite(DP_PIN, HIGH); 
  }
}

void driveSegments(int digitVal) {
  for (int segVal = 0; segVal < (sizeof(SEG_PINS) / sizeof(SEG_PINS[0])); segVal++) {
    digitalWrite(SEG_PINS[segVal], digitSegVals[digitVal][segVal]);
  }
}

void checkButtons()  {
  // Read the pushbutton one input pin:
  int btn1State = digitalRead(RUN_PIN);
  // Compare the button reading to its previous reading
  if (btn1State != lastBtn1State) {
    // If the reading has changed, update the state based on the reading
    if (btn1State == LOW) {
      // If the current reading is LOW then the button went from off to on:
      stateOne = ! stateOne; //true; // set state one
      Serial.println(F("Button one pressed"));
    } else {
      // If the current state is HIGH then the button went from on to off:
      Serial.println(F("Button one released"));
    }
    // Save the current reading as the last reading, for next time through the loop
    lastBtn1State = btn1State;
    // Delay a little bit to avoid bouncing
    delay(20);
  }
    // Read the pushbutton two input pin:
  int btn2State = digitalRead(RST_PIN);
  // Compare the button reading to its previous reading
  if (btn2State != lastBtn2State) {
    // If the reading has changed, update the state based on the reading
    if (btn2State == LOW) {
      // If the current reading is LOW then the button went from off to on:
      stateTwo = ! stateTwo; //true; // set state two
      Serial.println(F("Button two pressed"));
    } else {
      // If the current state is HIGH then the button went from on to off:
      Serial.println(F("Button two released"));
    }
    // Save the current reading as the last reading, for next time through the loop
    lastBtn2State = btn2State;
    // Delay a little bit to avoid bouncing
    delay(20);
  }
}
*/