#include <Arduino.h>

// ------------ Pins -------------
const uint8_t ledPins[5] = {PA2, PA3, PA4, PA5, PA6};
const uint8_t blinkPin = PA9;
const uint8_t buttonPin = PA1;

// ------------ Running LED task state -------------
volatile bool blinkRequest = false;
volatile uint32_t lastISRTime = 0;

uint8_t data = 0x80;               // start bit pattern
uint32_t lastStepTime = 0;
const uint32_t stepInterval = 500; // ms

// ------------ Blink task state -------------
bool blinking = false;
int blinkCount = 0;
bool blinkLevel = false;
uint32_t lastBlinkTime = 0;
const uint32_t blinkInterval = 500; // ms

// ISR: just request blink (debounced)
void handlePB1() {
  uint32_t now = millis();
  if (now - lastISRTime > 500) {   // debounce 200ms
    blinkRequest = true;
    lastISRTime = now;
  }
}

void writePattern(uint8_t v) {
  for (int i = 0; i < 6; i++) {
    digitalWrite(ledPins[i], (v >> i) & 1);
  }
}

void setup() {
  // outputs
  for (int i = 0; i < 6; i++) pinMode(ledPins[i], OUTPUT);
  pinMode(blinkPin, OUTPUT);
  digitalWrite(blinkPin, LOW);

  // button
  pinMode(buttonPin, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(buttonPin), handlePB1, FALLING);

  writePattern(0x00);
}

void loop() {
  uint32_t now = millis();

  // If interrupt requested and not already blinking -> start blinking task
  if (blinkRequest && !blinking) {
    blinkRequest = false;

    blinking = true;
    blinkCount = 0;
    blinkLevel = false;
    lastBlinkTime = now;
    digitalWrite(blinkPin, LOW);
  }

  // ---------------- Blink task (PA8) ----------------
  if (blinking) {
    if (now - lastBlinkTime >= blinkInterval) {
      lastBlinkTime = now;

      blinkLevel = !blinkLevel;
      digitalWrite(blinkPin, blinkLevel);

      // Count only HIGH pulses as "1 blink"
      if (blinkLevel == true) {
        blinkCount++;
      }

      // Stop after exactly 7 ON pulses
      if (blinkCount >= 6) {
        blinking = false;
        digitalWrite(blinkPin, LOW);
      }
    }

    // IMPORTANT: while blinking, we pause running LED task
    return;
  }

  // ---------------- Running LED task (PA0..PA7) ----------------
  if (now - lastStepTime >= stepInterval) {
    lastStepTime = now;

    writePattern(data);

    data >>= 1;
    if (data == 0x00) {
      data = 0x80;  // restart cycle after reaching end
    }
  }
}