main.cpp

/**
 * Supermarket Console System
 *
 * Author: ImEasooon
 * License: Education
 * GitHub: https://github.com/ImEasooon
 *
 * Description:
 * A simple console-based supermarket system written in C++.
 */

#include <iostream>
#include <iomanip>
#include <cctype>
#include <fstream>
#define Size 20
using namespace std;

struct menu{
	string product;
	       
	float price, total = 0;
	    
	int quantity = 0;
};

bool login();
bool registration();
bool validation(string username);
void cate_menu();
void category(menu cart[], int start, int end, string title);
void invoice(menu cart[]);

void main(){
	struct menu cart[Size] = {{"Fish", 12.00, 0, 0}, {"Chicken", 8.50, 0, 0}, {"Beef", 17.00, 0, 0}, {"Pork", 10.50, 0, 0},
		  					{"Potato", 5.00, 0, 0}, {"Cabbage", 7.00, 0, 0}, {"Onion", 3.00, 0, 0}, {"Cucumber", 2.00, 0, 0},
		  					{"Bread", 4.00, 0, 0}, {"Biscuit", 5.60, 0, 0}, {"Noodle", 8.00, 0, 0}, {"Rice", 16.00, 0, 0},
		  					{"Water", 1.00, 0, 0}, {"Milk", 8.50, 0, 0}, {"Coffee", 12.00, 0, 0}, {"Beer", 20.50, 0, 0},
		  					{"Potato Chips", 5.30, 0, 0},{"Chocolate", 15.80, 0, 0}, {"Popcorn", 9.00, 0, 0}, {"Nuts", 6.00, 0, 0}};
	
	char method;
	
	cout<<"Welcome to Supermarket"<<endl;
	
	while(true){
		cout<<"Press L to Log in"<<endl;
		cout<<"Press S to Sign up"<<endl;
		cout<<endl;
		
		cout<<"Enter: ";
		cin>>method;
		cout<<endl;
		
		method = toupper(method);
		
		if(method == 'L'){
			if(login()) break;
		}
		
		else if(method == 'S'){
			if(registration()){
				if(login()) break;
			}
		}
		
		else{
			cout<<"Invalid Option. Please try again!"<<endl;
			cout<<endl;
		}
	}
	
	int selected_cate;
	
	while(true){
		cate_menu();
		
		cout<<"Enter 0 to quit the process"<<endl;
		cout<<"Enter number to choose the category: ";
		cin>>selected_cate;
		
		if(cin.fail()){
		    cout<<"Invalid input! Please enter a valid number."<<endl;
		    cin.clear();
		    cin.ignore(1000, '\n');
		    continue;
		}
		
		if(selected_cate == 0) break;
		
		switch(selected_cate){
			case 1: category(cart, 0, 3, "Meat"); break;
			case 2: category(cart, 4, 7, "Vegetable"); break;
			case 3: category(cart, 8, 11, "Food"); break;
			case 4: category(cart, 12, 15, "Drink"); break;
			case 5: category(cart, 16, 19, "Snack"); break;
			default: cout<<"Invalid category!"<<endl;
		}
	}
	
	invoice(cart);
}

bool login(){
	string username, password, cus_username, cus_password;
	int attempt = 3;
	bool status = false;
	
	cout<<"Only 3 attempts allowed"<<endl;
	
	while(attempt--){
		cout<<"Username: ";
		cin>>username;
		
		cout<<"Password: ";
		cin>>password;
		
		ifstream log_system("./data/Customer Account.txt");
		
		if(!log_system){
			cout<<"File Opening Error!"<<endl;
			return false;
		}
		
		while(log_system >> cus_username >> cus_password){
			if(username == cus_username && password == cus_password){
				status = true;
				break;
			}
		}
		
		log_system.close();
		
		if(status){
			cout<<"Login successful!"<<endl;
			cout<<"Press any key to continue...";
			cin.ignore();
			cin.get();
			cout<<endl;
	        return true;
		}
		
		else{
			cout<<"Invalid credentials. Attempts left: "<<attempt<<" time(s)"<<endl;
			cout<<endl;
		}
	}
	
	cout<<"Too many failed attempts. Access denied!"<<endl;
	cout<<endl;
	return false;
}

bool registration(){
	string username, psswrd, cfm_psswrd;
	bool isValid = false;
	
	while(!isValid){
		cout<<"Username: ";
		cin>>username;
		
		isValid = validation(username);
	}
	
	while(true){
		cout<<"Password: ";
		cin>>psswrd;
		
		cout<<"Confirm Password: ";
		cin>>cfm_psswrd;
		
		if(psswrd == cfm_psswrd) break;
		
		cout<<"Passwords do not match. Try again!"<<endl;
	}
	
	ofstream regis_system("./data/Customer Account.txt", ios::app);
	
	if(!regis_system){
		cout<<"File Opening Error!"<<endl;
		return false;
	}
	
	regis_system<<username<<" "<< psswrd<<endl;

	regis_system.close();
	
	cout<<"Account registered successfully!"<<endl;
	cout<<"Press any key to continue...";
	cin.ignore();
	cin.get();
	cout<<endl;
	
	return true;
}

bool validation(string username){
	ifstream check("./data/Customer Account.txt");
	string chk_username, password;
	
	while(check >> chk_username >> password){
	    if(chk_username == username){
	        cout<<"Username already exists!\n";
	        return false;
	    }
	}
	
	check.close();
	return true;
}

void cate_menu(){
	cout<<endl;
	cout<<"Choose the category for products"<<endl;
	cout<<"--------------------------------------------------------------"<<endl;
	cout<<"No	|		Category"<<endl;
	cout<<"--------------------------------------------------------------"<<endl;
	cout<<"1	|		Meat"<<endl;
	cout<<"2	|		Vegetable"<<endl;
	cout<<"3	|		Food"<<endl;
	cout<<"4	|		Drink"<<endl;
	cout<<"5	|		Snack"<<endl;
	cout<<"--------------------------------------------------------------"<<endl;
	cout<<endl;
}

void category(menu cart[], int start, int end, string title){
	int quantity;
	char x;
	
	cout<<"--------------------------------------------------------------"<<endl;
	cout<<left<<setw(5)<<"No"<<"|"
		<<setw(20)<<title<<"|"
		<<setw(5)<<"Price($)"<<endl;
	cout<<"--------------------------------------------------------------"<<endl;
	for(int i = start; i <= end; i++){
	    cout<<left<<setw(5)<<char('A' + (i - start))<<"|"
	        <<setw(20)<<cart[i].product<<"|"
	        <<fixed<<setprecision(2)
			<<setw(5)<<cart[i].price<<endl;
	}
	cout<<"--------------------------------------------------------------"<<endl;
	
	cout<<"Enter Q to quit the process"<<endl;
	
	while(true){
		cout<<"Your Option: ";
		cin>>x;
	
		x = toupper(x);
		
		if(x == 'Q') break;
		
		// ASCII: A = 65, B = 66, C = 67, D = 68
		// E.g. D - A = 3
		int index = (x - 'A') + start;
		
		if(index >= start && index <= end){
			cout<<"Quantity: ";
			cin>>quantity;
			
			if(cin.fail()){
			    cout<<"Invalid input! Please enter a valid number."<<endl;
			    cin.clear();
			    cin.ignore(1000, '\n');
			    continue;
			}

			if(quantity <= 0){
			    cout<<"Invalid quantity!"<<endl;
			    continue;
			}
			
			cart[index].quantity += quantity;
			
			cart[index].total += quantity * cart[index].price;
			
			cout<<quantity<<" "<<cart[index].product<<" added to cart!"<<endl;
			
			cout<<endl;
		}
		
		else{
			cout<<"Invalid Option. Please try again!"<<endl;
			cout<<endl;
		}
	}
	
	cout<<endl;
}

void invoice(menu cart[]){
	int x, y = 1;
	float total = 0;
	ofstream receipt;
	
	receipt.open("./data/Supermarket Receipt.txt", ios::out);
	
	receipt<<"-----------------------------------------------------"<<endl;
	receipt<<"              Supermarket  Receipt                   "<<endl;
	receipt<<"-----------------------------------------------------"<<endl;	
	receipt<<left<<setw(10)<<"No"
		    <<setw(30)<<"Products"
		    <<setw(15)<<"Qty"
		    <<"$"<<endl;
	receipt<<"-----------------------------------------------------"<<endl;
	receipt<<fixed<<setprecision(2);
	for(x=0; x<Size; x++){
		if(cart[x].quantity > 0){
			receipt<<left<<setw(10)<<y
				    <<setw(30)<<cart[x].product
				    <<setw(15)<<cart[x].quantity
				    <<fixed<<setprecision(2)
				    <<cart[x].total<<endl;
			y++;
		}
	}
	
	receipt<<"-----------------------------------------------------"<<endl;
	for(x=0; x<Size; x++){
		if(cart[x].total > 0){
			total = total + cart[x].total;
		}
	}
	receipt<<"Total Payment		: $ " <<total<<endl;
	receipt<<"-----------------------------------------------------"<<endl;
	
	receipt.close();
	
	if(y == 1){
	    cout<<"Cart is empty!"<<endl;
	    return;
	}

	cout<<"A receipt has been generated"<<endl;
}