import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Scanner;


public class UserDataBase {
	private class User{
		public int account;
		public int password;
		public int balance;
		public String language;

		public User(int acc, int pass, int bal, String lang) {
			account = acc;
			password = pass;
			balance = bal;
			language = lang;
		}
		@Override
		public String toString() {
			super.toString();

			return account + "\t" + password + "\t" + balance + "\t" + language;
		}

	}

	private ArrayList<User> users = new ArrayList<User>();
	private String filename;

	public UserDataBase(String databasefile) {
		filename = databasefile;
		File file = new File(databasefile);

		if (!file.exists()) {
			// create the file
			try {
				FileWriter fw = new FileWriter(databasefile);
				BufferedWriter writer = new BufferedWriter(fw);
				writer.write("");
				writer.close();
			} catch (IOException e) {
				e.printStackTrace();
			}

			return;
		}

		try {
			Scanner sc = new Scanner(file);
			sc.useDelimiter("\t");
			while (sc.hasNextLine()) {
				String line = sc.nextLine();
				String[] ray = line.split("\t");

				int account = Integer.parseInt(ray[0]);
				int password = Integer.parseInt(ray[1]);
				int balance = Integer.parseInt(ray[2]);
				String language = ray[3];

				User user = new User(account, password, balance, language);
				users.add(user);
			}
		} catch (FileNotFoundException e) {
			return;
		}
	}

	public User getUser(int acc){
		for (User user : users) {
			if (user.account == acc) {
				return user;
			}
		}

		return null;
	}

	public boolean findUser(int acc){
		User user = getUser(acc);
		if(users.contains(user)){
			return true;
		} else {
			return false;
		}
	}

	public int getBalance(int acc){
		User user = getUser(acc);
		if(findUser(acc)) {
			return user.balance;
		}else{
			System.out.println("User not found in database");
			return -1;
		}
	}

	public int getPassword(int acc){
		User user = getUser(acc);
		if(findUser(acc)) {
			return user.password;
		}else{
			System.out.println("User not found in database");
			return -1;
		}
	}

	public void addUser(int acc, int pass, int bal, String lang){
		if (findUser(acc)) {
			System.out.println("User is already in the database");
		}

		User user = new User(acc,pass,bal,lang);
		users.add(user);
		writeToFile();
	}

	public boolean removeUser(int account){
		User user = getUser(account);
		boolean result = users.remove(user);
		writeToFile();
		return result;
	}

	public boolean decreaseBalance(int account,int amount){
		User user = getUser(account);
		if (user == null) {
			return false;
		}

		user.balance = user.balance - amount;
		return true;
	}

	public boolean increaseBalance(int account,int amount){
		User user = getUser(account);
		if (user == null) {
			return false;
		}

		user.balance = user.balance + amount;
		return true;
	}

	public void writeToFile() {
		// loop through the users and write to file
		try {
			FileWriter fw = new FileWriter(filename);
			BufferedWriter writer = new BufferedWriter(fw);
			Boolean firstline = true;
			for (User user : users) {
				if (!firstline) {
					writer.newLine();
				}
				writer.write(user.toString());
				firstline = false;
			}
			writer.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}



}