package de.dis2017;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

/**
 * Small helper class for forms.
 */
class FormUtil {
    /**
     * Reads a string from the console.
     *
     * @param label
     *         Label that is shown before the input
     * @return read string
     */
    static String readString(String label) {
        return readString(label, "");
    }
    
    /**
     * Reads a string from the console.
     *
     * @param label
     *         Label that is shown before the input
     * @param defaultValue
     *         the default value in case an empty input is provided
     * @return read string
     */
    static String readString(String label, String defaultValue) {
        String         ret   = null;
        BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
        
        try {
            System.out.print(label + (!defaultValue.isEmpty() ? "[" + defaultValue + "]" : "") + ": ");
            ret = stdin.readLine();
            ret = ret.isEmpty() ? defaultValue : ret;
        } catch (IOException e) {
            e.printStackTrace();
        }
        
        return ret;
    }
    
    /**
     * Reads a password from the console.
     *
     * @return the entered password
     */
    static String readPassword() {
        String password  = "";
        System.out.print("Password: ");
        if (System.console() != null) {
            password = String.valueOf(System.console().readPassword());
        } else {
            try {
                BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
                password = stdin.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        
        return password;
    }
    
    /**
     * Reads a password from the console.
     *
     * @return the entered password
     */
    static String readPassword(String oldPassword) {
        String password = readPassword();
        return password.isEmpty() ? oldPassword : password;
    }
    
    /**
     * Reads an integer from the console.
     *
     * @param label
     *         Label that is shown before the input
     * @return read integer
     */
    static int readInt(String label) {
        return readInt(label, -1);
    }
    
    /**
     * Reads an integer from the console.
     *
     * @param label
     *         Label that is shown before the input
     * @param defaultValue
     *         the default value
     * @return read integer
     */
    static int readInt(String label, int defaultValue) {
        int     ret             = 0;
        boolean finished        = false;
        String  defaultValueStr = defaultValue == -1 ? "" : String.valueOf(defaultValue);
        
        while (!finished) {
            String line = readString(label, defaultValueStr);
            
            try {
                ret = Integer.parseInt(line);
                finished = true;
            } catch (NumberFormatException e) {
                System.err.println("Invalid input: Please insert a valid number!");
            }
        }
        
        return ret;
    }
}