/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */
package org.apache.ivy.util;

import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;

import javax.swing.ImageIcon;
import javax.swing.JCheckBox;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

import org.apache.ivy.Ivy;

public final class CredentialsUtil {

    private static final class CredentialPanel extends JPanel {
        private static final int FIELD_LENGTH = 20;

        private JTextField userNameField = new JTextField(FIELD_LENGTH);

        private JTextField passwordField = new JPasswordField(FIELD_LENGTH);

        private JCheckBox rememberDataCB = new JCheckBox("remember my information");

        CredentialPanel(Credentials credentials, File passfile) {
            GridBagLayout layout = new GridBagLayout();
            setLayout(layout);
            GridBagConstraints c = new GridBagConstraints();
            c.insets = new Insets(2, 2, 2, 2);

            c.gridx = 1;
            c.gridheight = 1;
            c.gridwidth = 2;
            String prompt = credentials.getRealm() != null ? "Enter username and password for \""
                    + credentials.getRealm() + "\" at " + credentials.getHost()
                    : "Enter username and password for " + credentials.getHost();
            add(new JLabel(prompt), c);

            c.gridy = 1;
            c.gridwidth = 1;

            add(new JLabel("username: "), c);
            c.gridx = 2;
            add(userNameField, c);
            c.gridx = 1;
            c.gridy++;

            if (credentials.getUserName() != null) {
                userNameField.setText(credentials.getUserName());
            }

            if (credentials.getPasswd() == null) {
                add(new JLabel("passwd:  "), c);
                c.gridx = 2;
                add(passwordField, c);
                c.gridx = 1;
                c.gridy++;
            } else {
                passwordField.setText(credentials.getPasswd());
            }

            if (passfile != null) {
                c.gridwidth = 2;
                add(rememberDataCB, c);
                c.gridy++;
            }
            c.gridwidth = 2;
            add(new JLabel(), c); // spacer

        }
    }

    public static Credentials promptCredentials(Credentials c, File passfile) {
        c = loadPassfile(c, passfile);
        if (c.getUserName() != null && c.getPasswd() != null) {
            return c;
        }
        CredentialPanel credentialPanel = new CredentialPanel(c, passfile);
        if (JOptionPane.showOptionDialog(null, credentialPanel, c.getHost() + " credentials",
            JOptionPane.OK_CANCEL_OPTION, 0, new ImageIcon(Ivy.class.getResource("logo.png")),
            null, new Integer(JOptionPane.OK_OPTION)) == JOptionPane.OK_OPTION) {
            String username = credentialPanel.userNameField.getText();
            String passwd = credentialPanel.passwordField.getText();
            if (credentialPanel.rememberDataCB.isSelected()) {
                Properties props = new EncrytedProperties();
                props.setProperty("username", username);
                props.setProperty("passwd", passwd);
                FileOutputStream fos = null;
                try {
                    fos = new FileOutputStream(passfile);
                    props.store(fos, "");
                } catch (Exception e) {
                    Message.warn("error occurred while saving password file " + passfile + ": " + e);
                } finally {
                    if (fos != null) {
                        try {
                            fos.close();
                        } catch (Exception e) {
                            // ignored
                        }
                    }
                }
            }
            c = new Credentials(c.getRealm(), c.getHost(), username, passwd);
        }
        return c;
    }

    public static Credentials loadPassfile(Credentials c, File passfile) {
        if (passfile != null && passfile.exists()) {
            Properties props = new EncrytedProperties();
            FileInputStream fis = null;
            try {
                fis = new FileInputStream(passfile);
                props.load(fis);
                String username = c.getUserName();
                String passwd = c.getPasswd();
                if (username == null) {
                    username = props.getProperty("username");
                }
                if (passwd == null) {
                    passwd = props.getProperty("passwd");
                }
                return new Credentials(c.getRealm(), c.getHost(), username, passwd);
            } catch (IOException e) {
                Message.warn("error occurred while loading password file " + passfile + ": " + e);
            } finally {
                if (fis != null) {
                    try {
                        fis.close();
                    } catch (IOException e) {
                        // ignored
                    }
                }
            }
        }
        return c;
    }

    private CredentialsUtil() {
    }
}
