/**
    * Copyright 2011, Aiki IT, FotoRenamer
    * <p/>
    * Licensed 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
    * <p/>
    * http://www.apache.org/licenses/LICENSE-2.0
    * <p/>
   * 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 de.aikiit.fotorenamer.gui;
  
  import de.aikiit.fotorenamer.exception.InvalidDirectoryException;
  import de.aikiit.fotorenamer.exception.NoFilesFoundException;
  import de.aikiit.fotorenamer.image.CreationDateFromExifImageRenamer;
  import de.aikiit.fotorenamer.util.LocalizationHelper;
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.apache.logging.log4j.util.Strings;
  
  import javax.swing.*;
  import java.awt.*;
  import java.awt.datatransfer.DataFlavor;
  import java.awt.dnd.DnDConstants;
  import java.awt.dnd.DropTarget;
  import java.awt.dnd.DropTargetDropEvent;
  import java.awt.event.KeyAdapter;
  import java.awt.event.KeyEvent;
  import java.io.File;
  import java.io.IOException;
  
  import static de.aikiit.fotorenamer.util.LocalizationHelper.getBundleString;
  import static de.aikiit.fotorenamer.util.LocalizationHelper.getParameterizedBundleString;
  
  /**
   * This component provides a means to select images that are to be renamed.
   *
   * @author hirsch, 13.10.2003
   * @version 2004-01-08
   */
  class ImageDirectorySelector extends JPanel {
      /**
       * The logger of this class.
       **/
      private static final Logger LOG =
              LogManager.getLogger(ImageDirectorySelector.class);
  
      /**
       * Contains the selected directory as a text field or any user input.
       */
      private JTextField textField = null;
      /**
       * The UI's button to start directory selection.
       */
      private JButton browseButton = null;
      /**
       * An image icon that is displayed as part of the button.
       */
      private final ImageIcon imageIcon;
  
      /**
       * Default constructor provides means to create an imageSelect with a given
       * image icon that is able to only work on directories.
       *
       * @param icon This icon is used as a picture in the select
       *             button.
       */
      ImageDirectorySelector(final ImageIcon icon) {
          super();
          this.imageIcon = icon;
          init();
      }
  
      /**
       * Provides a means to disable this component
       * (e.g. during run of file renaming).
       *
       * @param enable Enable/disable this component.
       */
      public final void setEnabled(final boolean enable) {
          textField.setEnabled(enable);
          browseButton.setEnabled(enable);
      }
  
      /**
       * This method is used as a blocking call until the user selects something
       * in the UI.
       *
       * @return Returns whether anything is selected within the current
       * configuration.
       */
      // TODO improve design, let class emit an event in case a directory was selected
      public final boolean isWaiting() {
          return Strings.isEmpty(getSelectedDirectory());
     }
 
     /**
      * Initialize internal UI components.
      */
     private void init() {
         createBaseLayout();
         initTextField();
         makeTextFieldDragAndDropable();
         makeTextFieldReactOnEnterOrCopyPasteFromMainUI();
     }
 
     private void createBaseLayout() {
         GridBagLayout grid = new GridBagLayout();
         GridBagConstraints gbc = new GridBagConstraints();
         gbc.insets = new Insets(0, 2, 0, 2);
         setLayout(grid);
 
         // Add field.
         gbc.gridx = 0;
         gbc.gridy = 0;
         gbc.gridheight = 1;
         gbc.gridwidth = 2;
         gbc.anchor = GridBagConstraints.WEST;
         textField = new JTextField(60);
         grid.setConstraints(textField, gbc);
         add(textField);
 
         // Add button.
         gbc.gridx = 2;
         gbc.gridy = 0;
         gbc.gridheight = 1;
         gbc.gridwidth = 1;
         gbc.anchor = GridBagConstraints.EAST;
 
         // show button
         browseButton = this.imageIcon == null
                 ? new JButton(
                 getBundleString(
                         "fotorenamer.ui.selector.title"))
                 : new JButton(
                 getBundleString(
                         "fotorenamer.ui.selector.title"), this.imageIcon);
         browseButton.setMnemonic(getBundleString("fotorenamer.ui.selector.title.mnemonic").charAt(0));
         browseButton.setMargin(new Insets(1, 1, 1, 1));
         grid.setConstraints(browseButton, gbc);
         add(browseButton);
     }
 
     private void initTextField() {
         // Add action listener and take current contents of textfield as start directory
         browseButton.addActionListener(event -> {
 
             String currentPath = getSelectedDirectory();
             JFileChooser fileDlg = new JFileChooser(com.google.common.base.Strings.isNullOrEmpty(currentPath) ? null : currentPath);
 
             fileDlg.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
             fileDlg.setDialogTitle(
                     getBundleString(
                             "fotorenamer.ui.selector.directory"));
             fileDlg.setApproveButtonText(getBundleString(
                     "fotorenamer.ui.selector.select"));
 
             if (fileDlg.showOpenDialog(this)
                     == JFileChooser.APPROVE_OPTION) {
                 // use getCanonicalPath() to avoid ..-path manipulations and
                 // try to set the selected file in the UI
                 try {
                     textField.setText(
                             fileDlg.getSelectedFile().getCanonicalPath());
                 } catch (IOException ioe) {
                     LOG.error("Error while selecting directory, extracted text is: "
                             + textField.getText());
                     LOG.error(ioe.getMessage());
                 }
             }
         });
     }
 
     private void makeTextFieldReactOnEnterOrCopyPasteFromMainUI() {
         // make textfield react on Enter/copied over from MainUIWindow
         textField.addKeyListener(new KeyAdapter() {
             @Override
             public void keyPressed(final KeyEvent e) {
                 if (e.getKeyCode() == KeyEvent.VK_ENTER) {
 
                     SwingWorker<Void, Void> worker = new SwingWorker<Void, Void>() {
                         @Override
                         protected Void doInBackground() {
                             if (isWaiting()) {
                                 showErrorPopup(getBundleString("fotorenamer.ui.error.nodirectory"), getBundleString("fotorenamer.ui.error.nodirectory.title"));
                                 return null;
                             }
 
                             // perform renaming
                             try {
                                 CreationDateFromExifImageRenamer renamer =
                                         new CreationDateFromExifImageRenamer(getSelectedDirectory());
                                 new Thread(renamer).start();
                             } catch (InvalidDirectoryException uv) {
                                 LOG.info("Invalid directory selected: {}", uv.getMessage());
                                 showErrorPopup(getParameterizedBundleString("fotorenamer.ui.error.invaliddirectory", uv.getMessage()), getBundleString("fotorenamer.ui.error.invaliddirectory.title"));
                             } catch (NoFilesFoundException kde) {
                                 LOG.info("No files found in {}", kde.getMessage());
                                 showErrorPopup(getParameterizedBundleString("fotorenamer.ui.error.nofiles", kde.getMessage()), getBundleString("fotorenamer.ui.error.nofiles.title"));
                             }
                             return null;
                         }
 
                         @Override
                         protected void done() {
                             // TODO how can I communicate with the surrounding UI to block the user from pressing the buttons
                             LOG.debug("Finished working, cannot reset UI from the selector itself. Should find a way to lock the startbutton somehow.");
                         }
                     };
                     // Execute the SwingWorker; GUI will not freeze
                     worker.execute();
                 }
             }
 
         });
     }
 
     private void makeTextFieldDragAndDropable() {
         // make textfield drag'n'dropable
         textField.setDropTarget(new DropTarget() {
             public synchronized void drop(DropTargetDropEvent evt) {
                 try {
                     evt.acceptDrop(DnDConstants.ACTION_COPY);
                     Object transferData = evt
                             .getTransferable().getTransferData(
                                     DataFlavor.javaFileListFlavor);
 
                     if (transferData instanceof java.util.List) {
                         //noinspection unchecked
                         java.util.List<File> droppedFiles = (java.util.List<File>) transferData;
                         if (!droppedFiles.isEmpty()) {
                             for (File droppedFile : droppedFiles) {
                                 if (droppedFile.isDirectory()) {
                                     final String path = droppedFile.getAbsolutePath();
                                     LOG.info("Drag'n'drop done for file: {} with {} element(s) received", path, droppedFiles.size());
                                     textField.setText(path);
                                     break;
                                 }
                             }
                         }
                     }
 
                 } catch (Exception ex) {
                     LOG.info("Drag'd'drop did not work due to exception", ex);
                 }
             }
         });
     }
 
     void showErrorPopup(final String message, final String title) {
         JOptionPane.showMessageDialog(null,
                 message,
                 title,
                 JOptionPane.ERROR_MESSAGE);
     }
 
     /**
      * Current directory is the representation of this component.
      *
      * @return The currently selected directory.
      */
     final String getSelectedDirectory() {
         String currentSelection = LocalizationHelper.removeCrLf(this.textField.getText());
         if (!com.google.common.base.Strings.isNullOrEmpty(currentSelection)) {
             currentSelection = currentSelection.replaceAll("~", System.getProperty("user.home"));
             currentSelection = currentSelection.trim();
             LOG.debug("User input transformed into {}", currentSelection);
         }
         return currentSelection;
     }
 }