DialogPasswordSettings.java

/*
 * Copyright (c) 2015 Jonas Kalderstam.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.nononsenseapps.notepad.ui.common;

import android.app.Dialog;
import android.content.DialogInterface;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.support.annotation.NonNull;
import android.support.design.widget.TextInputLayout;
import android.support.v4.app.DialogFragment;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.AlertDialog;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import com.nononsenseapps.notepad.R;

/**
 * Fragment which handles password setting.
 */
public class DialogPasswordSettings extends DialogFragment implements DialogInterface
        .OnShowListener {

    public static final String KEY_PASSWORD = "secretPassword";

    private EditText newPasswordText;
    private EditText confirmPasswordText;
    private EditText currentPasswordText;
    private TextInputLayout confirmPasswordLabel;
    private TextInputLayout currentPasswordLabel;

    public static void showDialog(final FragmentManager fm) {
        DialogPasswordSettings d = new DialogPasswordSettings();
        d.setArguments(Bundle.EMPTY);
        d.show(fm, "passwordsettings");
    }

    @NonNull
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        final AlertDialog d = new AlertDialog.Builder(getActivity()).setTitle(R.string.password)
                .setView(R.layout.dialog_password_settings).setNegativeButton(android.R.string
                        .cancel, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                dialog.dismiss();
            }
        }).setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                // Not used, see OnShow
                onOK(dialog);
            }
        }).create();

        d.setOnShowListener(this);

        return d;
    }

    @Override
    public void onStart() {
        super.onStart();
        Dialog dialog = getDialog();
        currentPasswordText = (EditText) dialog.findViewById(R.id.currentPassword);
        newPasswordText = (EditText) dialog.findViewById(R.id.tempPassword1);
        confirmPasswordText = (EditText) dialog.findViewById(R.id.tempPassword2);

        currentPasswordLabel = (TextInputLayout) dialog.findViewById(R.id.currentPasswordLabel);

        confirmPasswordLabel = (TextInputLayout) dialog.findViewById(R.id.tempPassword2Label);

        currentPasswordText.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
            }

            @Override
            public void afterTextChanged(Editable s) {
                currentPasswordLabel.setError(null);
            }
        });

        confirmPasswordText.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
            }

            @Override
            public void afterTextChanged(Editable s) {
                confirmPasswordLabel.setError(null);
            }
        });
    }

    @Override
    public void onShow(DialogInterface dialog) {
        final AlertDialog d = (AlertDialog) dialog;
        Button ok = d.getButton(AlertDialog.BUTTON_POSITIVE);
        // Override the actual on click listener to prevent dismissal of dialog
        ok.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                onOK(d);
            }
        });
    }

    private void onOK(DialogInterface dialog) {
        SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences
                (getContext());
        if (verifyCurrentPassword(sharedPreferences) && verifyNewPassword()) {
            savePassword(sharedPreferences);
            dialog.dismiss();
        }
    }

    private void savePassword(SharedPreferences sharedPreferences) {
        if (newPasswordIsEmpty()) {
            sharedPreferences.edit().remove(KEY_PASSWORD).apply();
        } else {
            sharedPreferences.edit().putString(KEY_PASSWORD, newPasswordText.getText().toString()
            ).apply();
        }
    }

    private boolean newPasswordIsEmpty() {
        return newPasswordText.getText().toString().isEmpty();
    }

    private boolean verifyNewPassword() {
        if (newPasswordText.getText().toString().equals(confirmPasswordText.getText().toString())) {
            return true;
        }

        confirmPasswordLabel.setError(getString(R.string.passwords_dont_match));
        return false;
    }

    private boolean verifyCurrentPassword(SharedPreferences sharedPreferences) {
        final String currentPassword = sharedPreferences.getString(KEY_PASSWORD, "");
        if (currentPassword.equals(currentPasswordText.getText().toString())) {
            return true;
        }

        currentPasswordLabel.setError(getString(R.string.password_incorrect));
        return false;

    }
}