package OAiP;

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;


public class Program2 {

    public static void main(String[] args) throws IOException {
        System.out.println("This program encrypt string according to the encoding table.\n");
        Scanner in = new Scanner(System.in);
        String reader[];
        String text = "", st1 = "", st2 = "";
        boolean inValid = true;
        do {
            System.out.println("Enter '1' if you want to load data from console, and '2' from file: ");
            switch (in.nextLine()) {
                case "1":
                    reader = loadData();
                    text = reader[0];
                    st1 = reader[1];
                    st2 = reader[2];
                    inValid = false;
                    break;
                case "2":
                    reader = loadDataFromFile();
                    text = reader[0];
                    st1 = reader[1];
                    st2 = reader[2];
                    inValid = false;
                    break;
            }
        } while (inValid);
        outputData(encrypter(text, st1, st2));
    }

    public static String[] loadDataFromFile() throws IOException {
        Scanner in = new Scanner(System.in);
        FileReader inF = new FileReader("orginal_string.txt");
        Scanner fileScanner = new Scanner(inF);
        boolean inValid = true;
        do {
            try {
                System.out.println("Enter input file directory: ");
                inF = new FileReader(in.nextLine());
                inValid = false;
            } catch (Exception e) {
                System.out.println("File not found");
            }
        } while (inValid);
        String reader[] = new String[3];
        reader[0] = fileScanner.nextLine();
        reader[1] = fileScanner.nextLine();
        reader[2] = fileScanner.nextLine();
        inF.close();
        return reader;
    }

    public static String encrypter(String text, String st1, String st2) {
        for (int i = 0; i < st1.length(); i++) {
            text = text.replaceAll(st1.charAt(i) + "", st2.charAt(i) + "");
        }
        return text;
    }

    public static void outputData(String text) throws IOException {
        Scanner in = new Scanner(System.in);
        System.out.println("Enter output file directory: ");
        FileWriter outF = new FileWriter(in.nextLine());
        System.out.println("Encrypted string: " + text);
        outF.write("Encrypted string: " + text);
        outF.close();
    }

    public static String[] loadData() {
        Scanner in = new Scanner(System.in);
        String reader[] = new String[3];
        System.out.println("Enter string for encrypting: ");
        reader[0] = in.nextLine();
        boolean inValid = true;
        do {
            System.out.println("Enter original string according to encoding table: ");
            reader[1] = in.nextLine();
            System.out.println("Enter final string according to encoding table: ");
            reader[2] = in.nextLine();
            if (reader[1].length() == reader[2].length()) {
                inValid = false;
            } else {
                System.out.println("Input error. Strings must have the same length.");
            }
        } while (inValid);
        return reader;
    }
}