#include<iostream>
#include<iomanip>
#include<fstream>
#include<cmath>
#include<cstdbool>
#include<string>
#include<conio.h>
#include<vector>
#include<string>
#include<algorithm>
#include<cstdio>
#include<limits>
#include<cctype>

using namespace std;

void book_issue_menu();
void user_issue_menu();

class book
{
	int ID_book;
	string title, author;
public:
	void add_book();
	void search_book();
	void show_books();
	book();
	~book();
};
book::book()
{}
book::~book()
{}

void book::add_book() {
	cout << "Creating new book: " << endl;
	cout << "ID: ";
	while (!(cin >> ID_book))
	{
		cout << "ID has to be a number.\nID:";
		cin.clear();
		cin.ignore(numeric_limits<streamsize>::max(), '\n');
	}

	fflush;
	cin.get();

	cout << "Title: " << "\t";
	getline(cin, title);

	cout << endl << "Author: ";
	while (getline(cin, author), find_if(author.begin(), author.end(), isalpha) == author.end())
	{
		cout << "You have to enter letters.\nAuthor: ";
	}

	fstream file("books.txt", ios::app);
	if (file.good() == true)
	{
		file << ID_book << endl;
		file << title << endl;
		file << author << endl;
		file.close();
	}
	cout << endl;
}
void book::search_book() {
	string title_1;
	string line;
	bool check = true;

	cout << "\nEnter title of book to search: ";
	cin.get();
	getline(cin, title_1);

	fstream file("books.txt");

	if (file.good() == true)
	{
		while (getline(file, line))
		{
			title = line;

			if ((title == title_1))
			{
				cout << "Book in stock.\n";
				check = false;
				break;
			}
		}
		if (check == true)
			cout << "Book not in stock.\n";
	}
	else
	{
		cout << "Cannot open the file.\n";
	}
}
void book::show_books() {
	string helper, line;
	int i = 0, line_counter = 0;

	cout << "BOOK LIST" << endl;

	fstream file("books.txt", ios::in);

	if (file.good() == true)
	{
		while (getline(file, helper))
		{
			if (i == 0) cout << "ID:";
			else if (i == 1) cout << "Title:";
			else if (i == 2)
			{
				cout << "Author:";
				i = -1;
			}
			i++;
			cout << helper << endl;
			line_counter++;
		}
		file.close();
	}
	cout << "Number of books: " << line_counter / 3 << endl << endl;
}

class user
{
	int ID_user;
	string name;
public:
	void add_user();
	void search_user();
	void show_users();
	user();
	~user();

};
user::user()
{
}
user::~user()
{
}

void user::add_user() {

	cout << "Creating new user: " << endl;
	cout << "ID: ";
	while (!(cin >> ID_user))
	{
		cout << "ID has to be a number.\nID:";
		cin.clear();
		cin.ignore(numeric_limits<streamsize>::max(), '\n');
	}

	fflush;
	cin.get();

	cout << endl << "Name: ";
	while (getline(cin, name), find_if(name.begin(), name.end(), isalpha) == name.end())
	{
		cout << "You have to enter letters.\Name: ";
	}

	fstream file("users.txt", ios::app);
	if (file.good() == true)
	{
		file << ID_user << endl;
		file << name << endl;

		file.close();
	}
	cout << endl;
}
void user::search_user() {
	string name_1;
	string line;
	bool check = true;

	cout << "\nEnter name of user to search: ";
	cin.get();
	getline(cin, name_1);

	fstream file("books.txt");

	if (file.good() == true)
	{
		while (getline(file, line))
		{
			name = line;

			if ((name == name_1))
			{
				cout << "User in base.\n";
				check = false;
				break;
			}
		}
		if (check == true)
			cout << "User not in base.\n";
	}
}
void user::show_users() {
	string helper;
	int i = 0;

	cout << "USER LIST" << endl;

	fstream file("books.txt", ios::in);

	if (file.good() == true)
	{
		while (getline(file, helper))
		{
			if (i == 0) cout << "ID:";
			else if (i == 1)
			{
				cout << "Name:";
				i = -1;
			}
			i++;
			cout << helper << endl;
			file.close();
		}
	}
	cout << endl;
}

int main()
{
	char choice;
	choice = 0;

	while (choice < '1' || choice > '3')
	{
		cout << "---=== Library ==---" << endl;
		cout << "What do you want to do?"
			<< endl << "1. Book Menu"
			<< endl << "2. User Menu"
			<< endl << "3. Exit." << endl
			<< "Enter your choice: " << "\t";
		cin >> choice;
		switch (choice) {
		case '1':
			system("cls");
			book_issue_menu();
			break;
		case '2':
			system("cls");
			user_issue_menu();
			break;
		case '3':
			system("cls");
			break;
		}
	}
	return 0;
}

void book_issue_menu() {
	book b1;
	int choice;
	choice = 0;

	while (choice != 4)
	{
		cout << "---=== BOOK MENU ==---" << endl;
		cout << "What do you want to do?"
			<< endl << "1. Add new book."
			<< endl << "2. Search book."
			<< endl << "3. Display all books."
			<< endl << "4. Exit to main menu." << endl
			<< "Enter your choice: " << "\t";
		cin >> choice;
		switch (choice) {
		case 1:
			system("cls");
			b1.add_book();
			break;
		case 2:
			system("cls");
			b1.search_book();
			break;
		case 3:
			system("cls");
			b1.show_books();
			break;
		case 4:
			system("cls");
			return;
		}
	}
}
void user_issue_menu() {
	user u1;
	int choice;
	choice = 0;

	while (choice != 4)
	{
		cout << "---=== BOOK MENU ==---" << endl;
		cout << "What do you want to do?"
			<< endl << "1. Add new user."
			<< endl << "2. Search user."
			<< endl << "3. Display all users."
			<< endl << "4. Exit to main menu." << endl
			<< "Enter your choice: " << "\t";
		cin >> choice;
		switch (choice) {
		case 1:
			system("cls");
			u1.add_user();
			break;
		case 2:
			system("cls");
			u1.search_user();
			break;
		case 3:
			system("cls");
			u1.show_users();
			break;
		case 4:
			system("cls");
			return;
		}
	}
}