#include <Keypad.h>

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'A', 'B', 'C', 'D'}, 
  {'E', 'F', 'G', 'H'},
  {'I', 'J', 'K', 'L'},
  {'M', 'N', 'O', 'P'} 
};

byte rowPins[ROWS] = {7, 6, 5, 4};
byte colPins[COLS] = {3, 2, 1, 0};

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

const int ledPin = 13;
unsigned long holdStart = 0;
char currentKey = NO_KEY;
bool isHolding = false; 

unsigned long totalHoldTime = 0; 

struct HoldData {
  char key;
  unsigned long holdTime;
};

const int maxRecords = 10;
HoldData holdDataArray[maxRecords];
int recordCount = 0;

void addHoldData(char key, unsigned long holdTime) {
  if (recordCount < maxRecords) {
    holdDataArray[recordCount++] = {key, holdTime};
  } else {
    holdDataArray[maxRecords - 1] = {key, holdTime};
  }

  for (int i = 0; i < recordCount - 1; i++) {
    for (int j = 0; j < recordCount - i - 1; j++) {
      if (holdDataArray[j].holdTime < holdDataArray[j + 1].holdTime) {
        HoldData temp = holdDataArray[j];
        holdDataArray[j] = holdDataArray[j + 1];
        holdDataArray[j + 1] = temp;
      }
    }
  }
}

void printHoldData() {
  Serial.println("Сохранённые данные об удержании:");
  for (int i = 0; i < recordCount; i++) {
    Serial.print("Клавиша: ");
    Serial.print(holdDataArray[i].key);
    Serial.print(" | Время удержания: ");
    Serial.print(holdDataArray[i].holdTime / 1000.0, 3);
    Serial.println(" секунд");
  }
}

void setup() {
  pinMode(ledPin, OUTPUT);
  digitalWrite(ledPin, LOW);
  Serial.begin(9600);
}

void loop() {
  char key = keypad.getKey();

  if (key) {
    if (key != currentKey) {
      currentKey = key;
      holdStart = millis();
      isHolding = true;
    }
  }

  if (isHolding && currentKey != NO_KEY) {
    if (!keypad.getState()) {
      unsigned long holdDuration = millis() - holdStart;

      totalHoldTime += holdDuration;

      Serial.println(" ");
      Serial.print("Отпущена клавиша : ");
      Serial.println(currentKey);
      Serial.print("Время удержания: ");
      Serial.print(holdDuration / 1000.0, 3);
      Serial.println(" секунд");

      addHoldData(currentKey, holdDuration);
      printHoldData();

      Serial.println("Статистика удержания:");
      Serial.print("Общее время удержания: ");
      Serial.print(totalHoldTime / 1000.0, 3);
      Serial.println(" секунд");

      if (holdDuration >= 2000) {
        digitalWrite(ledPin, HIGH);
        Serial.print("Светодиод будет гореть");
        Serial.print(holdDuration / 1000.0, 3);
        Serial.println(" секунд");
        delay(holdDuration);
        digitalWrite(ledPin, LOW);
      }

      currentKey = NO_KEY;
      isHolding = false;
    }
  }
}