#include <bits/stdc++.h>
using namespace std;

class Customer
{

    int id ;
    char name[20], password[20], username[20];

public :


    // getter
    int getId()
    {
        return id;
    }

    char* getName()
    {
        return name;
    }

    char* getPassword()
    {
        return password;
    }

    char* getUsername()
    {
        return username;
    }



    // search about id in file of customers
    bool searchId(int val)
    {

        ifstream inFile("data.txt", ios::in);

        if(inFile.is_open())
        {
            Customer c1 ;
            while(!inFile.eof())
            {
                inFile.read( (char *)&c1, sizeof(c1) );

                if(c1.getId() == val) return true;
            }

        }
        else
            cout <<"Cann't be opened the file \n" ;
        inFile.close();

        return false;
    }


    bool validId(double val)
    {
        return val > 0 and int(val)==val and !searchId(val) ;
    }

    void setID() // new user only
    {
        double x ;
        cout << "Enter ID : ";
        cin >> x;


        while(!validId(x))
        {
            cout <<"Invalid Id , please try again \n";
            cout << "Enter ID : ";
            cin >> x;

        }
        id = int(x);
    }


    void setName()
    {
        cout <<"Enter Name : ";
        cin >> name;
    }

    bool validUsername(char val[20])    // search if found same username in the file
    {

        ifstream inFile("data.txt", ios::in);

        if(inFile.is_open())
        {
            Customer c1 ;
            while(!inFile.eof())
            {
                inFile.read( (char *)&c1, sizeof(c1) );

                if(strcmp(c1.getUsername(), val)==0 ) return false;
            }
        }
        else
            cout <<"Cann't be opened the file \n" ;

        inFile.close();

        return true;
    }

    void setUsername( int option )
    {
        if(option == 1) // new user -> check if valid username
        {
            char temp[20];
            cout <<"Enter username : " ;
            cin >> temp;

            while(!validUsername(temp))
            {
                cout <<"Invalid username , please try again \n";
                cout << "Enter username : ";
                cin >> temp;
            }

            for(int i=0; i< 20; i++) username[i]=temp[i];

        }

        else  // old user
        {
            cout << "Enter username : ";
            cin >> username;
        }
    }

    void setPassword()
    {
        cout <<"Enter Password : ";
        cin >> password;
    }


    bool validLogin( char user[20], char pass [20] )
    {
        ifstream inFile("data.txt", ios::in);

        if(inFile.is_open())
        {
            Customer c1 ;
            while(!inFile.eof())
            {
                inFile.read( (char *)&c1, sizeof(c1) );

                if(strcmp(c1.getUsername(), user)==0
                        and strcmp(c1.getPassword(), pass)==0)
                {
                    cout << "Logged in Successfully \n Welcome \n";
                    cout << "Id\tname\tusername\tpassword\n";
                    cout << c1.getId() << '\t' << c1.getName() << '\t' <<
                         c1.getUsername() << '\t' << c1.getPassword() << "\n";
                    return true;
                }
            }
        }
        else
            cout <<"Cann't be opened the file \n" ;
        return false;
    }

    string decryted(string s)
    {
        for(int i=0 ; i < 20 ; i++ )
            s[i]+='&';
        return s;
    }

    string incryted(string s)
    {
        for(int i=0 ; i < 20 ; i++ )
            s[i]-='&';
        return s;
    }
    void printCustomers()
    {
        ifstream inFile("data.txt", ios::in);
        if(inFile.is_open())
        {
            Customer c1 ;
            cout <<"ID\tName\tUsername\tpassword\n\n";
            while(!inFile.eof())
            {
                inFile.read((char *)&c1, sizeof(c1));


                string temp  = c1.getPassword();

                if(!inFile.eof())
                    cout <<c1.getId() <<'\t' << c1.getName() <<'\t' <<
                         c1.getUsername() << '\t' << decryted(temp) << "\n";
            }
        }
        else cout <<"Cann't opened this file\n";

        inFile.close();

    }

};


int main()
{


    Customer c1 ;
    c1.printCustomers();

    ofstream out("data.txt", ios::out | ios::app );
    int choise = 0;
    cout << "1.new user sign up : \n2.old user log in : ";
    cout <<"\nEnter your choice : ";
    cin >> choise;
    if(choise==1)  // new user (id , name , username, password)
    {
        c1.setID();
        c1.setName();
        c1.setUsername(1);
        c1.setPassword();

        out.write( (char*)&c1, sizeof(c1));

    }
    else
    {

        c1.setUsername(2);
        c1.setPassword();

        while(!c1.validLogin(c1.getUsername(), c1.getPassword()))
        {
            cout << "Invalid logging in \t please try again :\n";
            c1.setUsername(2);
            c1.setPassword();
        }
    }

    out.close();


    return 0;
}