LANCON~1.CPP

#include <iostream.h>
#include <conio.h>
#include <time.h>
#include<string.h>
#include<stdlib.h>
#include<stdio.h>
#include<fstream.h>
#include<ctype.h>
void sp(int down,int left);
void userControlPanel(char *uname);
void  createChatroom(char *creator);
char uname[30];
// all users share the chatrooms.txt
char chatrooms[500][30]; //All chatrooms collected from file
int chatroom_count =0; //no_of chats;
char chatroom[30]; //current chatroom;
/* Custom encoding rules followed in file io
   1. '-' denotes end of a field(username,pw, etc) and implies a space in output.
   2. '.' denotes end of record (user) and implies a next line charater.
   3. '*' denotes start  of record (user)
   4 "_" denote data attribute spacing (space in username allwos muiltiword )
   5."@" denotes the end of record
   ex. *test subject-pwd-example next. is one record
*/
 void encode(char *attribute) {
   for(int i = 0 ;i<strlen(attribute);i++) {
     if(attribute[i] == ' ' || attribute[i] == '.') {
	attribute[i] = '_';
     }
   }
 }
//message class start
  // Sample implementation code

  /* void main() {
     clrscr();
     message msg1;
     msg1.inputMessage();
     msg1.output();
     getch();
  } */


//general blueprint for messages
 class message {
   char title[30];
   char from[30];
   char to[30];
   char msg[200];
  public:
  int msg_status;
  /* msg status of 1 indicates user confirmed success delivery of message
    msg status of 0 indicates a error */
//prototypes
    void inputMessage();
    void checkInput(char x[300],int max);
    void output();
//default constructor
   message() {
     strcpy(title,"error") ;
     strcpy(from,"error");
     strcpy(to,"error");
     strcpy(msg,"error");
     msg_status = 0;
   }
 }; //end of message class


//validator for inputs to the message objects
   void message::checkInput(char x[300],int max) {
     if(!(strlen(x) <= max)) {
      cout << "Input must be less than 30 characters";
      msg_status = 0;
      //add input function here.
    }
   }
//Output message
   void message :: output() {
      cout<< endl;
      cout << "message start" << endl;
      puts(from) ;  cout << endl;
      puts(to) ;    cout << endl;
      puts(title);  cout << endl;
      puts(msg);    cout << endl;
      cout << "message end" << endl;
   }
//Input message
   void message :: inputMessage() {
    char ch;
   input:
     strcpy(from,"CurrentUser");   //Chage crt user with the logged in user
     cout << "Input user id of reciever: " <<endl;
     cin.getline(to,30);
     cout << "Input title of message : " << endl;
     cin.getline(title,30);
     cout << "Input message : " << endl;
     cin.getline(msg,200,'.');
     cout << "Send ? ... (Y/N) ";
     cin >> ch;
    if(ch == 'Y' || ch == 'y') {
	msg_status = 1;
	cout << "Message send.";
     } else {
	goto input;
     }
     cout << endl;
   }

//message end

//Sample implementation for user class
/*
void main()
{
	User x;
	x.create();
	x.login();
	x.logout();
	cout<<x.time();
	getch();
} */
//ui designing function
 void sp(int down, int left) {
   for(int i =0;i<down;i++) {
    cout << "\n";
   }
   for(int l =0;l<left;l++) {
    cout << " ";
   }
 }
//chatroom start
class chatroom {
//participants
   char pp[10][10];
   int max;
  public:
  int ppsize ;
  chatroom() {
    ppsize = 0;
    max =20;
  }
  //custom max users
  chatroom(int i) {
     max =i;
  }
   void create(char *creator);
//print participants
   void printpp();
};

void chatroom :: create(char *creator) {
   clrscr();
   char ch;
   char name[30];
   char p_input[30];
   strcpy(pp[0],creator);
//intializing p_input  and pp size
   strcpy(p_input,"empty");
   cout << endl << "Create new chatroom ? (Y/N): ";
   cin >>ch;
   if(ch == 'Y' || ch == 'y') {
      cout << endl << "Enter name of chatroom: ";
      gets(name);
   //cap on max users is 100 by defulat
      cout << "Enter end to terminate." << endl;
    int index;
    for(ppsize =1,index =1;ppsize<=max;ppsize++,index++) {
       cout << endl << "Input participant " << ppsize << ":" ;
       gets(p_input);
       if(strcmp(p_input,"end") == 0 || strcmp(p_input,"END") == 0) {
	 break;
       }else{
	strcpy(pp[index],p_input);
       }
    }//end of forloop
   } // end of Y/N if statement
}; //endof create function;

void chatroom :: printpp() {
  cout << endl << "Participants are:" ;
  cout << endl;
  for(int i =0;i<ppsize-1;i++) {
    puts(pp[i]);
  }
}
//chatroom end

//Users start
  class user {
	char username[30];
	char pw[30];
	char about[100];
	float activity;
   public:
	float start,mins,end,seconds;
     //default constuctor
       void uname(char input[30]);
       user() {
	strcpy(username,"empty");
	strcpy(pw,"empty");
	strcpy(about,"empty");
	activity = 0;
      }
    //start timer on login
       void timestart() {
	 start= time(0);
       }
       void writeToDb() {
	 fstream db;
	 db.open("users.txt",ios::out|ios::app);
	 if(!db) {
	  clrscr();
	  cout << endl << "Error \n";
	  cout << "Cannot open database of users.";
	 }
	 db << "*" << username << "-" << pw << "-" << about <<"."<< "\n";
	 db.close();
       }
   //Create new user
       void create()  {
	 sp(1,2);
	 cout << "Registration: ";
	 cin.ignore();
	 sp(3,2);
	 cout<<"Enter user name: ";
	 cin.getline(username,30);
	 encode(username);
	 cin.ignore(0,'\n');
	 sp(1,2);
	 cout<<"Enter password: ";
	 cin.getline(pw,30);
	 encode(pw);
	 sp(1,2);
	 cout << "About yourself [100 wrds max] :  " ;
	 sp(1,2);
	 cout << "(Terminate with .)" ;
	 sp(1,0);
	 cin.getline(about,100,'.');
	 encode(about);
	 sp(0,2);
	 writeToDb();
	 cout<<"Registeration complete!!";
       }



	//stop and log time on user logout
	  void logout() {
	    end=time(0);
	    seconds=difftime(end,start);
	    mins=seconds/60;
	}

};
//intialises a temp variable with username value
       void user :: uname(char input[30]) {
	  for(int i =0;i<30;i++) {
	   input[i] = username[i];
	  }
       }
//User class definition end

 //File io functions  Start
   int getFileSize(char f[30]) {
    ifstream file(f, ios::in | ios::binary);
    if(!file) {
     return -1;
    }
    file.seekg(0, ios::end);
    int fileSize = file.tellg();
    file.close();

    return fileSize;
   }

//reads the .txt file database
   void readDb(char file[30]) {
     clrscr();
     int count =0; ///for users.txt
      int pp_count=0; // for chatrrom.txt
     int char_count =0 ; // for chatroom buffer
     cout << "DB:" << endl;
       fstream	db;
       db.open(file,ios::in | ios::binary);
       if(!db) {
	cerr << "Db link error. Contact Creator";
       } else {
    //If db link successful
	int fs = getFileSize("users.txt");
      for(int i =0;i<fs;i++) {
	 char i;  //temp char buffer
	 db >> i;  //adds the input into the input stream
       //checking for eof
       if(db.eof()) {
	 break;
       }
       if(!isalpha(i)) {
	 switch(i) {
	  case '-' :
	  //if we are accessing the user db
	   if(strcmp(file,"users.txt") == 0) {
	    sp(1,2);
	   } else {
	    pp_count++;
	   }//end of else
	   break;
	  case '*':
	   pp_count =0; //reset
	   char_count = 0;
	   //no of the record i.e first chatroom second chatroom etc.
	   count++;
	   cout << count ;
	   sp(0,1); //needed as part of count and chatrrom name
	    break;
	  case '.':
	   cout << endl;
	   break;
	  case '_':
	   cout << " ";
	   break;
	  default:
	   cout << " ";
	   break;
	 }   //end of switch
       } else {
	  if(pp_count ==0){
	    if(strcmp(file,"chatrooms.txt") == 0){
	      int pointer = count - 1;
	      chatrooms[pointer][char_count] = i;
	      char_count++;
	      cout << i;
	     } else {
	      cout << i;
	     }
	   } else {
	    if(strcmp(file,"users.txt") ==0) {
	     cout << i;
	    } else {
	     continue;
	    }
	  }
       }//end of else
      }//end of for loop
      db.close();
      cout << endl;
      if(strcmp(file,"users.txt") == 0) {
      cout << "No of users: " << count;
      }
     }//end of file check
    }
//end of read db function


//Checks for user presence in Db
  int DbQuery(char uname[30],char pwd[30]) {
     clrscr();
      /*
       in a single cycle(i.e pointer goes from * to next * [one record])
       two - symbols are encountered for start and end of password
       A cycle:
	1. * - indicates start of cycle
	     pointer is reset
	2. all characters are filled into buffer A
	3. First - is encountered, pointer is reset ,query is made
	   and characters therafter are placed in buffer B
	     - if query unsuccessful the cycle is terminated
	       and pointer reset
	4. second - encountered terminates the cycle
	   pointer is reset and buffer A is intiated
      */

     /*
      States
	s_counter
	  0- not processing, searching for *
	  1- processing to a buffer
       a_counter
	  0- name is getting filled up from input stream
	  1- pw is getting filled from input strem
     */
       char name[30] ;  //buffer A
       char pw[30] ;    //buffer B
       int pointer =0;
       int s_counter =0;
       int a_counter =0;
       int flag =0;
       fstream	db;
       db.open("users.txt",ios::in | ios::binary);
       if(!db) {
	cerr << "Db link error. Contact Creator";
       } else {
    //If db link successful
	int fs = getFileSize("users.txt");
      for(int i =0;i<fs;i++) {
	 char i;  //temp char buffer
	 db >> i;  //i intilized with temp val
       //checking for eof
       if(db.eof()) {
	 break;
       }
       if(!isalpha(i)) {
	  if(i == '*') {
	  memset(name,'\0',30);
	  memset(pw,'\0',30);
	  pointer =0;
	    if(s_counter == 0) {
	     s_counter =1;
	    } else {
	     s_counter =0;
	     a_counter =0;
	    }
	  } else if(i == '-') {
	    if(a_counter == 0) {
	    //DEBUGGING
	     /* clrscr();
	      cout << name << "  " << uname <<endl ;
	      getch();  */
	      if(strcmp(name,uname) != 0) {
		s_counter =0;
		a_counter =0;
		//debuggin code
	     /*	cout << "user name does not match record";
		getch();*/
		continue;
	      } else {
	       //deBUGGING code	cout << "match found";
		a_counter++;
		memset(name,'\0',pointer);
		memset(pw,'\0',pointer);
		pointer = 0;
		continue;
	      }
	    }else { //A!=0
	     //debuggin code
	     /*
	      cout << " " << pw << "  org password  " << pwd << endl ;
	      getch(); */
	       if(strcmp(pwd,pw) != 0) {
		clrscr();
		cout << "Wrong password";
		getch();
		break;
	       } else {
		 //sucessfull username and password match
		 clrscr();
		 flag =1;
		 break;
	       }
	    } //end of '-' handling code
	  } else if(i == '_') {
	    if(s_counter == 0) {
	     continue;
	    } else {
	      if(a_counter ==0) {
		name[pointer] = ' ';
		pointer++;
	      }  else {
		pw[pointer] = ' ';
		pointer++;
	      }
	    }
	  }
       } else {
	  if(a_counter == 0) {
	   name[pointer] = i;
	   pointer++;
	  } else {
	   pw[pointer] = i;
	   pointer++;
	  }
       }//end of else
      }//end of for loop
    }//end of file check
    return flag;
  }


 // FIle io end


 //homescreen functionilty start
   void existingUser() {
    //login screen
    clrscr();
    char uname[30];
    char pwd[30];
    sp(1,2);
     cout << "Login: ";
     cin.ignore();
     sp(3,2);
     cout<<"Enter user name: ";
     cin.getline(uname,30);
     cin.ignore(0,'\n');
     sp(1,2);
     cout<<"Enter password: ";
     cin.getline(pwd,30);
     sp(1,2);
     int res = DbQuery(uname,pwd);
      if(!res) {
	clrscr();
	cout << "The username " << uname << "does not exist";
      } else {
	userControlPanel(uname);
      }
     getch();
   }

 //User Menu Screen
     void userControlPanel(char *uname) {
      int ch ;
      sp(1,1);
      cout << "Welcome back, " << uname;
      sp(3,3);
      cout << "1.Create Chatroom" ;
      sp(2,3);
      cout << "2.Join Chatroom";
      sp(2,3);
      cout << "Input ch number: " ;
      cin >> ch;
      if(ch == 1 ) {
      // createChatroom(uname);
      } else if(ch == 2) {
       //
      } else {
       clrscr();
       cout << "invalid option" ;
       getch();
       userControlPanel(uname);
      }
     }
  //User Registration
   void newUser() {
    user newUser;
    clrscr();
    newUser.create();
   }

 //create Chatroom
   void createChatroom(char *c) {
     clrscr();
     puts(c);
   }

 //homescreen end

 void main() {
   clrscr();
   int user_ch;
  //Homescreen
    sp(1,0);
    cout << "LAN Messenger:";
    sp(3,3);
    cout << "1.New User" ;
    sp(1,3);
    cout << "2.Existing user";
    sp(1,3);
    cout << "3.Settings";
    sp(2,3);
    cout << "Input path no. ";
    cin >> user_ch;
    if(user_ch == 1) {
   //User Regstration path
     newUser();
    }else if(user_ch == 2) {
     existingUser();
    }else if(user_ch == 3) {
   //Admin Backend path
      clrscr();
      cout << "Welcome to admin settings:" << endl;
      cout << "Input pwd : ";
      char pwd[10];
      gets(pwd);
      if(!strcmp(pwd,"admin") || !strcmp(pwd,"ADMIN")){
	readDb("users.txt");
      } else {
	cout << "Wrong password";
      }
    }else {
     clrscr();
     cout << "Invalid choice" << endl;
     cout << "Restart app";
    }

   getch();
 }