Sun-Tracking Mechanism for 40W solar panel

// define pin numbers:
#define redbutton 12
#define greenbutton 13
#define IN1 6
#define IN2 9
#define IN3 10
#define IN4 11
#define ldrEast 7
#define ldrWest 8
#define ldrUp 4
#define ldrDown 5

int ldrEastState = 0; //variable for reading east LDR status
int ldrWestState = 0; //variable for reading west LDR status
int ldrUpState = 0; //variable for reading Up LDR status
int ldrDownState = 0; //variable for reading Down LDR status

void setup() {
  
pinMode(IN1, OUTPUT);//make two output pins
pinMode(IN2, OUTPUT);
pinMode(IN3, OUTPUT);//make two output pins
pinMode(IN4, OUTPUT);
pinMode(ldrEast, INPUT); //make LDR input pin
pinMode(ldrWest, INPUT); //make LDR input pin
pinMode(ldrUp, INPUT); //make LDR input pin
pinMode(ldrDown, INPUT); //make LDR input pin
pinMode(redbutton, INPUT); //make red button input pin
digitalWrite (redbutton, HIGH);
pinMode(greenbutton, INPUT); //make green button input pin
digitalWrite (greenbutton, HIGH);

}

void loop() {
  //check east-west orientation first
ldrEastState = digitalRead(ldrEast); //read east ldr
ldrWestState = digitalRead(ldrWest); //read west ldr
digitalWrite(IN1,LOW); //set signal to motor driver board to low
digitalWrite(IN2,LOW); //set signal to motor driver board to low
digitalWrite(IN3,LOW); //set signal to motor driver board to low
digitalWrite(IN4,LOW); //set signal to motor driver board to low

//manual overwrite to orientate panel to west
if (digitalRead (greenbutton) == LOW) {
  analogWrite (IN2,150); //turn motor CCW to go towards west
} else {
  digitalWrite (IN2,LOW);
  }

//manual overwrite to orientate panel to east
if (digitalRead (redbutton) == LOW) {
  analogWrite (IN1, 150); //turn motor CW to go towards east
} else {
   digitalWrite (IN1, LOW);
  }

if (ldrWestState == HIGH) {
  if (ldrEastState == LOW) {
    analogWrite (IN2,150); //turn motor CCW to go towards west
  } else {
    }
} 

if (ldrWestState == LOW) {
  if (ldrEastState == HIGH) {
    analogWrite (IN1, 150); //turn motor CW to go towards east
  } else {
    }
}
delay (500); //wait 0.5 second


//check up-down orientation after eas-west orientation has been adjusted
ldrUpState = digitalRead(ldrUp); //read up ldr
ldrDownState = digitalRead(ldrDown); //read down ldr
digitalWrite(IN1,LOW); //set signal to motor driver board to low
digitalWrite(IN2,LOW); //set signal to motor driver board to low
digitalWrite(IN3,LOW); //set signal to motor driver board to low
digitalWrite(IN4,LOW); //set signal to motor driver board to low

if (ldrUpState == HIGH) {
  if (ldrDownState == LOW) {
    analogWrite (IN3,150); //ON tilt motor to rotate up
  } else {
    }
} 

if (ldrUpState == LOW) {
  if (ldrDownState == HIGH) {
    analogWrite (IN4, 150); //ON tilt motor to rotate down
  } else {
    }
}
delay (500); //wait 0.5 second

}