package chapter13.servlet;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.util.HashMap;
import java.util.Map;

public class UserUtil {
	
	private static String userFile;
	public static Map<String, String> userMap;
	
	public UserUtil() {
		userFile = "c:/user.data";
	}
	
	public UserUtil(String file) {
		userFile = file;
		if(userMap == null) {
			getAllUser();
		}
	}
	
	public static boolean checkUser(String username) {
		if(userMap.containsKey(username)) {
			return false;
		}
		return true;
	}
	
	public static boolean login(String username, String password) {
		if(userMap.containsKey(username)) {
			if(password.equals(userMap.get(username))) {
				return true;
			}
		}
		return false;
	}
	
	public static boolean register(String username, String password) {
		addUser(username, password);
		return true;
	}
	
	private static void addUser(String username, String passwd) {
		userMap.put(username, passwd);
		
		File file = new File(userFile);
		try {
			FileWriter fw = new FileWriter(file);
			fw.write(username + " " + passwd);
			fw.close();
		} catch(Exception e) {
			
		}
	}
	
	private void getAllUser() {
		userMap = new HashMap<String, String>();
		File file = new File(userFile);

		try {
			if (!file.exists()) {
				file.createNewFile();
			} else {
				BufferedReader br = new BufferedReader(new FileReader(file));
				String strUser = br.readLine();
				while(strUser != null && !strUser.equals("")) {
					String[] strUsers = strUser.split(" ");
					userMap.put(strUsers[0], strUsers[1]);
				}
				
				br.close();
			}
		} catch (Exception e) {
		}
	}
	
	public static String printUser(String user, String passwd) {
		System.out.print(user + "||" + passwd);
		return user + "||" + passwd;
	}
}