multilayer security system

//Limitations:
//1. This code only works for Software Serial and not Hardware Serial
//2. Message length should not be greater than 70 letters
//3. Message should be encapsulated in "___"
#include <SoftwareSerial.h>
SoftwareSerial SIM900(10,11);


unsigned char buffer[200];  //to store the received data from gsm
int counter[20];   // to store the address of " in string

int count=0;      // used to point buffer array
int pnt=0;        // used to count counter array
int pnt1=0;      // to count : in string
int pnt2=0;      // flag to avoide multiple phone & msg print
String phone_num; // string to store phone number
String message_gsm;    // string to store message


 int Gpsdata;             // for incoming serial data 
  unsigned int finish =0;  // indicate end of message
  unsigned int pos_cnt=0;  // position counter
  unsigned int lat_cnt=0;  // latitude data counter 
  unsigned int log_cnt=0;  // longitude data counter
  unsigned int flg    =0;  // GPS flag 
  unsigned int com_cnt=0;  // comma counter
  char lat[20];            // latitude array
  char lg[20];             // longitude array
   void Receive_GPS_Data();
   int value1=0;
   int value2=0;
   int digit1=0;
   int digit2=0;
   float latt=0;
   int value3=0;
   int value4=0;
   int digit3=0;
   int digit4=0;
   float longi=0;
    int beforedecimal=0;
     float afterdecimal=0;
     int beforedecimal2=0;
     float afterdecimal2=0;
     float combined2=0;
     char latitude;
     char longitude;
   String message="";
     String message2="";
     String message3="";
     String mahi="";
     
   
   char charVal[10];               //temporarily holds data from vals
  String stringVal = "";     //data on buff is copied to this string
   char charVal2[10];               //temporarily holds data from vals
  String stringVal2 = "";     //data on buff is copied to this string
  
float latt_min =19.0110 ;
float latt_max= 19.0120;
float longi_min= 72.8300 ;
float longi_max=72.8330 ;

 

 
void setup()
{

  pinMode(4,OUTPUT);      // to fingerprint keypad
  pinMode(5,INPUT);        // password match conformation 
  pinMode(3,OUTPUT);    // to relay
  pinMode(2,INPUT);    //vibration sensor
 Serial.begin(9600); // setting baud rate to serial monitor
  SIM900.begin(19200); // setting baud rate to software serial
  delay(200);  // give time to log on to network.

  SIM900.print("AT+CMGF=1\r");  // set SMS mode to text
  delay(100);
  
  SIM900.print("AT+CNMI=2,2,0,0,0\r");  // blurt out contents of new SMS upon receipt to the GSM shield's serial out
  delay(100);
}


void loop()
{ 
   
  gps();
  // Now we simply display any text that the GSM shield sends out on the serial monitor
   if (latt >= latt_min && latt <= latt_max && longi >= longi_min && longi <= longi_max)
 {
   
   digitalWrite(4,HIGH);      // destination reached indication
 }
 else
 {
   digitalWrite(4,LOW);
 }
  if(SIM900.available()) // checks for any data from gsm
  {
    while(SIM900.available())  //
    {
      phone_num="";  //Initial clearing
      message_gsm="";    
      buffer[count++]=SIM900.read();    // Reading and storing in buffer
      if(count==200)break;              // buffer overflow
    }
   
   for(int a=0;a<201;a++)         
   {
     if(buffer[a]=='"')         // checks for character "
     {
      counter[pnt++]=a;         // storing address of character "
      }
   }
   
   for(int a=0;a<201;a++)
   {
     if(buffer[a]==':')       // checks for character :
     {
      pnt1++;                 // counting no. of :
      }
   
   if(pnt1==1 && pnt2==0)    // storing the data only once
   {
    for(int b=counter[0]+1;b<counter[0]+14;b++)
    {
     phone_num +=(char(buffer[b]));
    }
   
   
    for(int b=counter[6]+1;b<counter[6]+100;b++)
    {
     if(buffer[b]=='"')break;
     message_gsm +=(char(buffer[b]));
    }
    pnt2=1;
   }
  }

   
    clearBufferArray();    // clearing all variables & buffer
    count=0;
    pnt=0;
    pnt1=0;
    pnt2=0;
     
  }
   Serial.print("Phone No.:- ");
   Serial.println(phone_num);
   Serial.print("Message:- ");
   Serial.println(message_gsm);
   
   
   if (message_gsm=="FETCH")
{
  
  send_lat();
  send_lon();
  message_gsm="";
  phone_num="";
}

if (digitalRead(5)==1)  // open lock command
{digitalWrite(3,HIGH);      // to relay
}
/*if (digitalRead(2)==1)      //from vibration sensor
{
  send_vibration();
 }
 */
}
 
 
void clearBufferArray()  // Clearing buffer
{
  for (int i=0;i<count;i++)
  {buffer[i]=NULL;}
}
void gps()
{  message="";
   Receive_GPS_Data(); 
     lat_conversion(); 
     lon_conversion();
    /*Serial.print("Latitude : ");
     Serial.println(latt,6);
      
      Serial.print("Longitude : ");
      Serial.println(longi,6);*/
      
      message = "latitude=";
      message.concat(stringVal);
      //message = message + stringVal;
      message2 = "longitude=";
      //message.concat("longitude=");
      message2.concat(stringVal2);
     //Serial.print(message);
     //Serial.println(message2);
      //message2 = message2 + stringVal2;
      //message.concat(message2);
      //Serial.println(message);
      //Serial.println(message2);
      finish = 0;pos_cnt = 0;
      stringVal="";
      stringVal2="";
     
  
  
}


  
/************************************************************************************
  Function    : Receive_GPS_Data()
  Description : finding Latitudse and longitude from GPRMC message

************************************************************************************/
  void Receive_GPS_Data()
  {
    while(finish==0){
      while(Serial.available()>0){         // Check GPS data 
        Gpsdata = Serial.read();
        flg = 1;
       if( Gpsdata=='$' && pos_cnt == 0)   // finding GPRMC header
         pos_cnt=1;
       if( Gpsdata=='G' && pos_cnt == 1)
         pos_cnt=2;
       if( Gpsdata=='P' && pos_cnt == 2)
         pos_cnt=3;
       if( Gpsdata=='R' && pos_cnt == 3)
         pos_cnt=4;
       if( Gpsdata=='M' && pos_cnt == 4)
         pos_cnt=5;
       if( Gpsdata=='C' && pos_cnt==5 )
         pos_cnt=6;
       if(pos_cnt==6 &&  Gpsdata ==','){   // count commas in message 
         com_cnt++;
         flg=0;
       } 

       if(com_cnt==3 && flg==1){
        lat[lat_cnt++] =  Gpsdata;         // latitude
        flg=0;
        
       }

       if(com_cnt==5 && flg==1){
         lg[log_cnt++] =  Gpsdata;         // Longitude 
         flg=0;
       }

       if( Gpsdata == '*' && com_cnt >= 5){
         com_cnt = 0;                      // end of GPRMC message
         lat_cnt = 0;
         log_cnt = 0;
         flg     = 0;
         finish  = 1;

      }
    } 
 }
}
void lat_conversion()
{ float combined;
  float x = atof(lat);
  //Serial.println(x,4);
  int beforedecimal = x;
  //Serial.println(beforedecimal);
  float afterdecimal=(x-beforedecimal);
 //Serial.println(afterdecimal,4);
  while(value1<beforedecimal)
    {
    value1++;
    digit2++;
    if(digit2==100)
     {
     digit2=0;  
    digit1++;
    }
    }
    combined = afterdecimal+digit2;
    //Serial.println(combined,4);
   float sum0= combined/60;
    latt=digit1+sum0;
    dtostrf(latt, 2, 6, charVal);//4 is mininum width, 3 is precision; float value is copied onto buff
       //convert chararray to string
  for(int i=0;i<sizeof(charVal);i++)
  {
    stringVal+=charVal[i];
  }
 
// Serial.print(stringVal);
//Serial.println(digit1);
   // Serial.println(digit2);
}
void lon_conversion()
{ float combined2;
   float y = atof(lg);
   
   
 // Serial.println(y,4);
  int beforedecimal2 = y;
  //Serial.println(beforedecimal2);
  float afterdecimal2=(y-beforedecimal2);
  //Serial.println(afterdecimal2,4);
  while(value3<beforedecimal2)
    {
      value3++;
    digit4++;
    if(digit4==100)
     {
     digit4=0;  
    digit3++;
    }
    }
    combined2 = afterdecimal2+digit4;
    //Serial.println(combined2,4);
    float sum=combined2/60;
    //Serial.println(sum,6);
    longi=digit3+sum;
   dtostrf(longi, 2, 6, charVal2);//4 is mininum width, 3 is precision; float value is copied onto buff
       //convert chararray to string
  for(int i=0;i<sizeof(charVal2);i++)
  {
    stringVal2+=charVal2[i];
  }
  // Serial.println(stringVal2);
  //Serial.println(digit4);
}

void send_lat()
{ 
  SIM900.print("AT+CMGF=1\r");                                                        // AT command to send SMS message
  delay(100);
  SIM900.print("AT + CMGS = \"");                                     // recipient's mobile number, in international format
  SIM900.print(phone_num);
  SIM900.println("\"");
  delay(100);
  
  SIM900.println(message);        // message to send
  delay(100);
  SIM900.println((char)26);                       // End AT command with a ^Z, ASCII code 26
  delay(100); 
  SIM900.println();
  digitalWrite(13,HIGH);
  delay(5000);  // give module time to send SMS
 
   
   SIM900.print("AT+CMGF=1\r");  // set SMS mode to text
  delay(100);
  
  SIM900.print("AT+CNMI=2,2,0,0,0\r");  // blurt out contents of new SMS upon receipt to the GSM shield's serial out
  delay(100);
}


void send_lon()
{ 
  SIM900.print("AT+CMGF=1\r");                                                        // AT command to send SMS message
  delay(100);
  SIM900.print("AT + CMGS = \"");                                     // recipient's mobile number, in international format
  SIM900.print(phone_num);
  SIM900.println("\"");
  delay(100);
  
  SIM900.println(message2);        // message to send
  delay(100);
  SIM900.println((char)26);                       // End AT command with a ^Z, ASCII code 26
  delay(100); 
  SIM900.println();
  digitalWrite(13,HIGH);
  delay(5000);  // give module time to send SMS
   phone_num=""; // string to store phone number
   message_gsm="";    // string to store message
   
   SIM900.print("AT+CMGF=1\r");  // set SMS mode to text
  delay(100);
  
  SIM900.print("AT+CNMI=2,2,0,0,0\r");  // blurt out contents of new SMS upon receipt to the GSM shield's serial out
  delay(100);
}


void send_vibration()
{
   SIM900.print("AT+CMGF=1\r");                                                        // AT command to send SMS message
  delay(100);
  SIM900.print("AT + CMGS = \"");                                     // recipient's mobile number, in international format
  SIM900.print(phone_num);
  SIM900.println("\"");
  delay(100);
  
  SIM900.println("vibration detected");        // message to send
  delay(100);
  SIM900.println((char)26);                       // End AT command with a ^Z, ASCII code 26
  delay(100); 
  SIM900.println();
  digitalWrite(13,HIGH);
  delay(5000);  // give module time to send SMS
   phone_num=""; // string to store phone number
   message_gsm="";    // string to store message
   
   SIM900.print("AT+CMGF=1\r");  // set SMS mode to text
  delay(100);
  
  SIM900.print("AT+CNMI=2,2,0,0,0\r");  // blurt out contents of new SMS upon receipt to the GSM shield's serial out
  delay(100);
}