#include <TinyGPS++.h>
#include <TinyGPSPlus.h>
#include <SoftwareSerial.h>
#include <LiquidCrystal_I2C.h>
#include "Ultrasonic.h"
#include <Servo.h>

// Pins for the SIM800L module
#define SIM800_RX 8
#define SIM800_TX 7

#define GPS_RX 6
#define GPS_TX 5


Servo myservo;
unsigned long metalDetectedAt = 0;
bool binOpen = false;
// --- Pin Definitions ---
#define TRIG_PIN 9
#define ECHO_PIN 10
#define NPN_SENSOR_PIN 2
#define SERVO_PIN 3


Ultrasonic ultrasonic(TRIG_PIN, ECHO_PIN);
int distance;
 int max_height = 400;
 long lastSentLevel = 0;
// Create instances
SoftwareSerial SIM800L(SIM800_RX, SIM800_TX);
SoftwareSerial gpsSerial(GPS_RX, GPS_TX);
TinyGPSPlus gps;

double latitude = 0.4600;double longitude= 32.5200;
String response;
int lastStringLength = 0; // Initialize to 0

LiquidCrystal_I2C lcd(0x27, 20, 4);  // assigning the lcd screen with its address
String link;
String PhoneNumber;  // Variable to store SIM card phone number

String PhoneNumbers[] = {
  "+256787917973",
  "+256780328639",
  "+256784258975"
};

void setup() {
  Serial.begin(9600);
  Serial.println("               GPS ISBAT UNIVERISTY             ");
  pinMode(NPN_SENSOR_PIN, INPUT);
  myservo.attach(SERVO_PIN);

  gpsSerial.begin(9600);
  SIM800L.begin(9600);
  SIM800L.println("AT+CMGF=1");
 // Serial.println("SIM800L started at 9600");
  delay(1000);
 // Serial.println("Setup Complete! SIM800L is Ready!");
  delay(1000);
  SIM800L.println("AT+CNMI=2,2,0,0,0");

  // Initialize lastStringLength
  lastStringLength = response.length();

  // Request SIM card phone number
  SIM800L.println("AT+CNUM");

  //lcd
  lcd.init();       //inilizing the lcd
  lcd.backlight();  // enabling the backlight
  lcd.setCursor(0, 0);
  lcd.print("ELECTRONIC");
  lcd.setCursor(0, 1);
  lcd.print("WASTE");
  lcd.setCursor(0, 2);
  lcd.print("BIN");
  lcd.setCursor(0, 3);
  lcd.print("ISBAT UNIVERSITY");
  delay(15000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("ELECTRONIC WASTE BIN");
}

void loop() {
  if (SIM800L.available() > 0) {
    response = SIM800L.readStringUntil('\n');
    // Check if the response contains the SIM card phone number
    if (response.indexOf("+CNUM") != -1) {
      // Extract the phone number from the response
      int startIdx = response.indexOf(",\"") + 2;
      int endIdx = response.indexOf("\",", startIdx);
      PhoneNumber = response.substring(startIdx, endIdx);
     Serial.println("Detected SIM card phone number: " + PhoneNumber);
     PhoneNumber.trim(); // Remove leading/trailing whitespace
     link = "AT+CMGS=\"" + PhoneNumber + "\"\r"; // Update the SMS command

    }
  }

  if (lastStringLength != response.length()) {
    GPS();
    // Perintah ON
    if (response.indexOf("CEKLOKASI") != -1) { //ganti CEK dengan keyword yang diinginkan jangan gunakan spasi
      SIM800L.println("AT+CMGF=1");     //Sets the GSM Module in Text Mode
      delay(1000);  // Delay of 1000 milliseconds or 1 second
      SIM800L.println(link);// The SMS text you want to send
      delay(100);
      SIM800L.println((char)26);// ASCII code of CTRL+Z
      delay(1000);
    }
  }
   //inductive proximity logic

  int state = digitalRead(NPN_SENSOR_PIN);  // Read inductive sensor

  if (state == LOW) {
    myservo.write(90);  // Move servo to 90 degrees (open)
       delay(200);
  }else
 {
    myservo.write(0);
   
  }
  //  distance = ultrasonic.read(CM);

  // Serial.print("Distance in CM: ");
  // Serial.println(distance);

  // distance = ultrasonic.read(INC);

  // Serial.print("Distance in Inches: ");
  // Serial.println(distance);

  //delay(1000);

   // Trigger the ultrasonic sensor
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  // Read the echo pin to get duration
  int duration = pulseIn(ECHO_PIN, HIGH);
  float distance = duration * 0.034 / 2;  // Convert duration to distance IN CM
  // invert distaces for the ultrasonic with an object reading
  long invert_distance = max_height - distance;
  //to avoid negative values
  if (invert_distance < 0) invert_distance = 0;
  if (invert_distance > max_height) invert_distance = max_height;
  // converting to percentages

  int level = (int)(((float)invert_distance / (float)max_height) * 100);

  //avoid negative percentage
  if (level < 0) level = 0;
  if (level > 100) level = 100;
   level = map(invert_distance, 5, max_height, 100, 0);
   level =constrain(level, 0, 100);
    
 String levelMessage = "";  // Create a string to store the message

if (level == 75 && lastSentLevel != 75) {
  levelMessage = "75% full - Please prepare to empty";
  Serial.println("****Notification: " + levelMessage +"************");
  link = "www.google.com/maps/place/" + String(latitude, 3) + "," + String(longitude, 3);
    Serial.println(link);
  sendsms(levelMessage);
  lastSentLevel = 75;
} else if (level == 95 && lastSentLevel != 95) {
  levelMessage = "95% full - Action is recommended";
  Serial.println("Notifcation: " + levelMessage);
  sendsms(levelMessage);
  link = "www.google.com/maps/place/" + String(latitude, 3) + "," + String(longitude, 3);
    Serial.println(link);
  lastSentLevel = 95;
} else if (level == 100 && lastSentLevel != 100) {
  levelMessage = "100% full - Immediate action required!";
  Serial.println("Emergency: " + levelMessage);
  sendsms(levelMessage);
  link = "www.google.com/maps/place/" + String(latitude, 3) + "," + String(longitude, 3);
    Serial.println(link);
  lastSentLevel = 100;
}


  lcd.setCursor(0, 1);
  lcd.print("BIN LEVEL IS: ");
  lcd.print(level);
  lcd.print("%   ");
 float latitude, longitude;
if (gpsSerial.available() > 0) {
    gps.encode(gpsSerial.read());
}
// Default fallback coordinates (Ndejje University, Uganda)
const float DEFAULT_LAT = 0.4600;
const float DEFAULT_LON = 32.5200;

// Process GPS data
while (gpsSerial.available() > 0) {
  gps.encode(gpsSerial.read());
}

// Use valid GPS data if available, otherwise use fallback
if (gps.location.isValid() && gps.location.age() < 2000) {
  latitude = gps.location.lat();
  longitude = gps.location.lng();
} else {
  latitude = DEFAULT_LAT;
  longitude = DEFAULT_LON;
}

// Print and show on LCD
//Serial.print("LAT=");  Serial.println(latitude, 4);
//Serial.print("LONG="); Serial.println(longitude, 4);

lcd.setCursor(0, 2);
lcd.print("LAT:");  lcd.print(latitude, 2);
lcd.print(" LOG:"); lcd.print(longitude, 2);


}


void GPS() {
  if (Serial.available()) {
    gps.encode(Serial.read());
  }
  if (gps.location.isUpdated()) {
    latitude = gps.location.lat();
    longitude = gps.location.lng();
    link = "www.google.com/maps/place/" + String(latitude, 3) + "," + String(longitude, 3);
    Serial.println(link);
  }
}
 void sendsms(String statusMessage) {
  // Get current or fallback GPS location
  float lat = gps.location.isValid() ? gps.location.lat() : 0.4600;
  float lon = gps.location.isValid() ? gps.location.lng() : 32.5200;
   // Construct Google Maps lintrk
  String googlelink = "https://maps.google.com/?q=" + String(lat, 6) + "," + String(lon, 6);

  // Fake date/time for now
  String timeStr = "12:00";  // Replace later with actual time
  String dateStr = "22/04/2025";  // Replace later with RTC or NTP
  
 
  // Compose message
  String MESSAGE = "ELECTRONIC WASTE BIN ISBAT\n";
   MESSAGE += "Bin Status: " + statusMessage + "\n";
   MESSAGE += "Location: " + googlelink + "\n";
   MESSAGE += "Date: " + dateStr + "\n";
   MESSAGE += "Time: " + timeStr + "\n";
   MESSAGE += "---------------------------------\n";

  // Simulate SMS by printing to Serial
  Serial.println(MESSAGE );
  
}