#include <SoftwareSerial.h>

#define GSM_TX_Modem_Pin      7
#define GSM_RX_Modem_Pin      8
#define Pressure_Sensor_1_Pin A0
#define Pressure_Sensor_2_Pin A1
#define Vibration_Sensor_Pin  2

String phoneNumber    = "+966559890918";
String message1       = "GSM Modem Working [SMS=Active]";
String message2       = "Soft Drop Detected";
String message3       = "Vibration Detected";
String message4       = "Heavy Drop Detected";
String message5       = "Box Overload Detected";

int overloaded_flag = 0;
int counter = 0;
//overloaded/ wighted 260
int Pressure_Sensor_1_threshold_overl = 200;
int Pressure_Sensor_2_threshold_overl = 200;

//soft 300
int Pressure_Sensor_1_threshold = 350;
int Pressure_Sensor_2_threshold = 350;

//heavy 500
int Pressure_Sensor_1_threshold_h = 450;
int Pressure_Sensor_2_threshold_h = 450;


int Pressure_Sensor_1_Value   = 0;
int Pressure_Sensor_2_Value   = 0;
int Vibration_Sensor_Value    = 0;


SoftwareSerial SIM900A(GSM_TX_Modem_Pin, GSM_RX_Modem_Pin);

void setup() {
  Serial.begin(9600);
  setup_Sensors();
  setup_GSM_Modem();
}



void SendMessage3() {
  SendMessage(message3);
  delay(2000);
}




void loop() {
  read_Sensors_and_Display_on_Serial();


  if ((Pressure_Sensor_1_Value > Pressure_Sensor_1_threshold_h) || (Pressure_Sensor_2_Value > Pressure_Sensor_2_threshold_h)) {
    SendMessage(message4);
    counter = 0;
    overloaded_flag = 0;
    delay(2000);
  }

  if ((Pressure_Sensor_1_Value > Pressure_Sensor_1_threshold) || (Pressure_Sensor_2_Value > Pressure_Sensor_2_threshold)) {
    SendMessage(message2);
    counter = 0;
    overloaded_flag = 0;
    delay(2000);
  }


  //overloaded/ wighted
  if ((Pressure_Sensor_1_Value > Pressure_Sensor_1_threshold_overl) || (Pressure_Sensor_2_Value > Pressure_Sensor_2_threshold_overl)) {
    counter += 1;
    if (counter > 10 && overloaded_flag == 0) {
      SendMessage(message5);
      overloaded_flag = 1;
      counter = 0;
    }
    delay(1000);
  }
}//end of LOOP




void setup_Sensors() {
  pinMode(Pressure_Sensor_1_Pin,  INPUT);
  pinMode(Pressure_Sensor_2_Pin,  INPUT);
  pinMode(Vibration_Sensor_Pin,   INPUT);
  attachInterrupt(digitalPinToInterrupt(Vibration_Sensor_Pin), SendMessage3, CHANGE);
}




void read_Sensors_and_Display_on_Serial() {
  Pressure_Sensor_1_Value   = analogRead(Pressure_Sensor_1_Pin);//0-1023
  Pressure_Sensor_2_Value   = analogRead(Pressure_Sensor_2_Pin);//0-1023
  Vibration_Sensor_Value    = digitalRead(Vibration_Sensor_Pin);//0-1
  Serial.print("Pressure [1] = ");
  Serial.print(Pressure_Sensor_1_Value);
  Serial.print("\t Pressure [2] = ");
  Serial.print(Pressure_Sensor_2_Value);
  Serial.print("\t Vibration = ");
  Serial.println(Vibration_Sensor_Value);
  Serial.println("------------------------------------------------------------------");
}




void setup_GSM_Modem() {
  SIM900A.begin(115200);   // Setting the baud rate of GSM Module
  Serial.println ("SIM900A Starting Up...");
  //delay(15000);
  Serial.println ("SIM900A Ready");
  SendMessage(message1);
}




void SendMessage(String msg)
{
  Serial.println ("Sending Message...");
  SIM900A.println("AT+CMGF=1");    //Sets the GSM Module in Text Mode
  delay(1000);
  Serial.println ("Set SMS Number...");
  Serial.println (phoneNumber);
  String phoneNumberCommand = "AT+CMGS=\"" + phoneNumber + "\"\r";
  SIM900A.println(phoneNumberCommand);
  delay(1000);
  Serial.println ("Set SMS Content");
  Serial.println (msg);
  SIM900A.println(msg);// Messsage content
  delay(100);
  Serial.println ("Finish");
  SIM900A.println((char)26);// ASCII code of CTRL+Z
  delay(1000);
  Serial.println ("Message has been sent -> [Done]");
}