#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include "DHT.h"
#include <SD.h>

#define DHTPIN 2     
#define DHTTYPE DHT22   // DHT 22  (AM2302), AM2321
#define LCD1_ADDR 0x27  // Alamat LCD
#define LCD1_COL 16     // LCD 16x2
#define LCD1_LIN 2
#define CS_PIN 10       // Pin CS SDCard
#define BUZPIN 6        // Pin Buzzer

LiquidCrystal_I2C lcd(LCD1_ADDR,LCD1_COL,LCD1_LIN);
DHT dht(DHTPIN, DHTTYPE);

const int buttonPin = 3;
const int panicButtonPin = 4;
const int panicLedPin = 5;
int periodeLedPanic;
int periodeDHT;
int periodeBackLightLCD;
int buttonState = 0;
int panicButtonState = 0;
unsigned long prevMilis1 = 0;
unsigned long prevMilis2 = 0;
unsigned long prevMilis3 = 0;
const String boardAddr = "";
const String devLoc1 = "";
const String devLoc2 = "";
float temp;
float humid;

struct Data {
  bool panicBtn;
  float dhtTemp;
  float dhtHumid;
};

Data data;

File sdFiles;

void setup() {
  // put your setup code here, to run once:
  periodeLedPanic = 500;
  periodeDHT = 2000;
  periodeBackLightLCD = 50;
  
  lcd.init();
  Serial.begin(9600);
  
  // splash screen
  lcd.setCursor(0,0);
  lcd.print("Airtech Devteam");
  lcd.setCursor(0,1);
  lcd.print("----- SOC -----");
  delay(2000);

  // inisialisasi
  pinMode(buttonPin, INPUT);
  pinMode(panicLedPin, OUTPUT);
  dht.begin();
  loadConfig();
}

void loop() {
  // put your main code here, to run repeatedly:
  // simpan timer sekarang
  unsigned long currentMilis = millis();

  if ((unsigned long)(currentMilis - prevMilis1) >= periodeDHT) {
    readDHT();
    prevMilis1 = currentMilis;
  }  

  // baca status tombol dan nyalakan backlight lcd jika tombol ditekan
  if ((unsigned long)(currentMilis - prevMilis2) >= periodeBackLightLCD) {
    lcdBacklight();    
    prevMilis2 = currentMilis;
  }

  // panic button
  if ((unsigned long)(currentMilis - prevMilis3) >= periodeLedPanic) {
    panicButton();
    prevMilis3 = currentMilis;
  }  
}

void loadConfig() {
  if (!SD.begin(CS_PIN)) {
    Serial.println("Inisialisasi SD Card Gagal");
    while (true);
  }
  Serial.println("SD Card OK");
/**
  // baca config dari SD Card
  sdFiles = SD.open("configs.txt");

  if (sdFiles) {
    Serial.println("Config OK"); 
    // baca baris 1
    sdFiles.seek(0 * 5);
    boardAddr = sdFiles.readStringUntil('\n');
    sdFiles.seek(1 * 8);
    devLoc1 = sdFiles.readStringUntil('\n');
    sdFiles.seek(2 * 13);
    devLoc2 = sdFiles.readStringUntil('\n');
    sdFiles.close();
  } else {
    Serial.println("Pembacaan file konfigurasi gagal");
  }
  Serial.print("Board Address :");
  Serial.print(boardAddr);
  Serial.println("");
  Serial.print("Board Location 1 :");
  Serial.print(devLoc1);
  Serial.println("");
  Serial.print("Board Location 2 :");
  Serial.print(devLoc2);
**/
  sdFiles = SD.open("configs.txt", FILE_READ);

  if (!sdFiles) {
    Serial.print("Text file tidak bisa dibuka");
    while(1);
  }

  while (sdFiles.available()) {
    String str = sdFiles.readStringUntil('\n');
    int str_len = str.length();
    String sub_str = str.substring(0,str_len);
    Serial.println(sub_str);
    /**
    str.trim();
    int str_len = str.length() + 1;
    char char_arr[str_len];
    str.toCharArray(char_arr, str_len);
    **/
    //Serial.println(str.c_str()); //Printing for debugging purpose         
    //do some action here
  }

  sdFiles.close();
}

void readDHT() {
    // baca suhu dan kelembaban
    temp = dht.readTemperature();
    humid = dht.readHumidity();

    if (isnan(temp) || isnan(humid)) {
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print(F("ERR: DHT"));
      lcd.setCursor(0,1);
      lcd.print(F("No Input"));
      return;
    }

    // tampilkan ke LCD
    lcd.setCursor(0,0);
    lcd.print(F("Temp : "));
    lcd.print(data.dhtTemp,1);
    data.dhtTemp = temp;
    //lcd.print(dht.readTemperature());
    lcd.print(F(" C"));
    lcd.setCursor(0,1);
    lcd.print(F("RH   : "));
    lcd.print(data.dhtHumid,1);
    data.dhtHumid = humid;
    //lcd.print(dht.readHumidity());
    lcd.print(F(" %"));
    //delay(2000);

    // detek suhu berlebih dan start buzzer
    if (temp >= 60) {
      buzzerStart(1000, 1000, 1000);
    } else if (temp <= 10) {
      buzzerStart(500, 1000, 2000);
    }
}

void lcdBacklight() {
    buttonState = digitalRead(buttonPin);

    if (buttonState == HIGH) {    
      lcd.backlight();
    } else {    
      lcd.noBacklight();
    }
}

void panicButton() {
    panicButtonState = digitalRead(panicButtonPin);

    if (panicButtonState == LOW) {
      digitalWrite(panicLedPin, LOW);
      data.panicBtn = LOW;
    } else {
      data.panicBtn = HIGH;
      // panic detected, led peringatan berkedip
      digitalWrite(panicLedPin, HIGH);
      digitalWrite(panicLedPin, LOW);
    }
}

void buzzerStart(int freq, int durasi, int tunda) {
  tone(BUZPIN, freq, durasi);
  delay(tunda);
}