/*
  Arduino | hardware-help
  Fan controlled by motion and TMP36
  Terminal_Dev — 6/15/24 at 8:48 PM
  I am trying to make a fan that turns on when the temperature
  is high enough AND when motion is detected (using PIR).
  I would like to add a delay to the motion sensor so the fan
  would turn off after no motion is detected.
  If someone could edit my Tinkercad circuit, that'd be a great help.
  Thanks Everyone!
  https://www.tinkercad.com/things/0pDOYpaFk7r-copy-of-fan-temp-auto/editel?sharecode=ltQXD_uW-MruWrI8tI2qz5uSLB6Bdf1DAzjU60Wb1pI
*/

#include <LiquidCrystal.h>
#include <OneWire.h>
#include <DallasTemperature.h>

const unsigned long SMPL_RATE = 1000;
const unsigned long FAN_DELAY = 10000;
const double MIN_LIMIT = 10;
const double MAX_LIMIT = 25;
const int RGB_PINS[] = {7, 6, 5};
const int PIR_PIN  = 4;
const int TEMP_PIN = 3;
const int FAN_PIN  = 2;
const int HEAT_PIN = A0;
const int MODE_PIN = A1;

unsigned long prevSenseTime = 0;
unsigned long prevMotionTime = 0;
int scaleMode = LOW;  // low is deg C
int oldMotionState = LOW;
bool isTimerOn = false;
bool isTriggered = false;

OneWire oneWire(TEMP_PIN);
DallasTemperature sensors(&oneWire);
LiquidCrystal lcd(13, 12, 11, 10, 9, 8);

bool checkPIR() {
  int motionState = digitalRead(PIR_PIN);
  if (motionState != oldMotionState) {
    oldMotionState = motionState;
    if (motionState == HIGH)  {
      Serial.println("Motion detected!");
      isTriggered = true;
    } else {
      Serial.println("Motion stopped");
      isTriggered = false;
    }
  }
  return isTriggered;
}

double getTemp()  {
  sensors.requestTemperatures();
  double tempC = sensors.getTempCByIndex(0);
  return tempC;
}

void updateDisplay(double temp, bool fan, bool heat)  {
  char dtosBuff[8];
  char sTempBuff[16];
  char lTempBuff[16];
  char fanBuff[12];
  char heatBuff[12];

  double scaleTemp = scaleMode ? ((temp * 9 / 5) + 32) : temp;
  dtostrf(scaleTemp, 2, 1, dtosBuff);

  snprintf (sTempBuff, 16, "Temp: %s%c%s", dtosBuff, char(176), (scaleMode ? "F" : "C"));
  snprintf (lTempBuff, 16, "Temp: %s%c%s  ", dtosBuff, char(223), (scaleMode ? "F" : "C"));
  snprintf(fanBuff, 12, "FAN %s ", fan ? "ON" : "OFF");
  snprintf(heatBuff, 12, "HEAT %s ", heat ? "ON" : "OFF");

  Serial.println(sTempBuff);
  Serial.println(fanBuff);
  Serial.println(heatBuff);
  Serial.println();
  lcd.setCursor(0, 0);
  lcd.print(fanBuff);
  lcd.setCursor(8, 0);
  lcd.print(heatBuff);
  lcd.setCursor(2, 1);
  lcd.print(lTempBuff);
}

void setup() {
  Serial.begin(115200);
  sensors.begin();
  lcd.begin(16, 2);
  for (int i = 0; i < 3; i++) {
    pinMode(RGB_PINS[i], OUTPUT);
  }
  pinMode(HEAT_PIN, OUTPUT);
  pinMode(FAN_PIN, OUTPUT);
  pinMode(MODE_PIN, INPUT_PULLUP);
  pinMode(PIR_PIN, INPUT);
  pinMode(TEMP_PIN, INPUT);
  // splash screen
  lcd.setCursor(2, 0);
  lcd.print("Terminal_Dev");
  lcd.setCursor(2, 1);
  lcd.print("Device V1.00");
  delay(2000);
  lcd.clear();
  Serial.println("System started\n");
}

void loop() {
  int rgbIdx = 0;
  bool fanState = false;
  bool heatState = false;
  bool motionState = false;

  scaleMode = digitalRead(MODE_PIN);
  //////////////////////////////////////////////////////////////////////
  bool isMotion = checkPIR();
  if (isMotion) {
    isTimerOn = true;
    prevMotionTime = millis();
  }
  // start the timer
  if (millis() - prevMotionTime >= FAN_DELAY) {
    isTimerOn = false;
  }
  //////////////////////////////////////////////////////////////////////
  if (millis() - prevSenseTime >= SMPL_RATE) {
    prevSenseTime = millis();
    double currTemp = getTemp();
    if (currTemp >= MAX_LIMIT) {
      rgbIdx = 0;
      if (isTimerOn)  fanState = true;
      heatState = false;
    } else if (currTemp <= MIN_LIMIT) {
      rgbIdx = 2;
      fanState = false;
      heatState = true;
    } else {
      rgbIdx = 1;
      fanState = false;
      heatState = false;
    }
    for (int i = 0; i < 3; i++) {
      digitalWrite(RGB_PINS[i], LOW);
    }
    digitalWrite(RGB_PINS[rgbIdx], HIGH);
    digitalWrite(FAN_PIN, fanState);
    digitalWrite(HEAT_PIN, heatState);
    updateDisplay(currTemp, fanState, heatState);
    //Serial.print("Timer: ");
    //Serial.println(isTimerOn ? "ON" : "OFF");
    //Serial.println();
  }
}