//library
#include <Wire.h> //I2C
#include <LiquidCrystal_I2C.h> //LCD protocol I2C 
LiquidCrystal_I2C lcd(0x27, 20, 4); 

int temp;
int photo;
int humi;

char state = '0';
char input;
unsigned long LstTime = 0;


void setup() {
  Serial.begin(9600);
  
  lcd.init();
  lcd.backlight();

  pinMode(A1,INPUT); //T
  pinMode(A2,INPUT); //P
  pinMode(A0,INPUT); //H
}

void loop() {
  //interupt
  if(millis() - LstTime >= 500){
    LstTime = millis();
    //start
    lcd.clear();
    Fucn_Temp();
    Fucn_Photo();
    Fucn_Humi();
    //end
    
  }
  Fucn_StateMachine();
}

void Fucn_StateMachine(){
  switch(state){
    case '0' ://main
    Fucn_LCDcase0();
    Serial.println("state :" + String(state));
    //read input
    input = Serial.read();
    if(input == '1'){
        state = '1';
    }
    if(input == '2'){
        state = '2';
    }
    if(input == '3'){
        state = '3';
    }
    break;

    case '1' ://Temp
    Fucn_LCDcase1();
    Serial.println("state :" + String(state));
    //read input
    input = Serial.read();
    if(input == '0'){
        state = '0';
    }
    break;
      
    case '2' ://Temp
    Fucn_LCDcase2();
    Serial.println("state :" + String(state));
    //read input
    input = Serial.read();
    if(input == '0'){
        state = '0';
    }
    break;
      
    case '3' ://Temp
    Fucn_LCDcase3();
    Serial.println("state :" + String(state));
    //read input
    input = Serial.read();
    if(input == '0'){
        state = '0';
    }
    break;
  }
 }

void Fucn_Temp(){
  temp = analogRead(A1);
}

void Fucn_Photo(){
  photo = analogRead(A2);
}

void Fucn_Humi(){
  humi = analogRead(A0);
}  
//case0    
void Fucn_LCDcase0(){
  lcd.setCursor(0,0); lcd.print("1: Temp");
  lcd.setCursor(0,1); lcd.print("2: Light");
  lcd.setCursor(0,2); lcd.print("3: SoilHumi");
  lcd.setCursor(13,3); lcd.print("[input]");
}
//case1      
void Fucn_LCDcase1(){
  lcd.setCursor(0,0); lcd.print("[Temp]");
  lcd.setCursor(7,1); lcd.print(temp);
  lcd.setCursor(12,1); lcd.print("C");
  lcd.setCursor(13,3); lcd.print("0:back");
}
//case2      
void Fucn_LCDcase2(){
  lcd.setCursor(0,0); lcd.print("[Light]");
  lcd.setCursor(7,1); lcd.print(photo);
  lcd.setCursor(12,1); lcd.print("lux");
  lcd.setCursor(13,3); lcd.print("0:back");
} 
//case3      
void Fucn_LCDcase3(){
  lcd.setCursor(0,0); lcd.print("SoilHumi");
  lcd.setCursor(7,1); lcd.print(humi);
  lcd.setCursor(12,1); lcd.print("H");
  lcd.setCursor(13,3); lcd.print("0:back");
}