RecentDocumentManager.java

/* 
 * License: source-license.txt
 * If this code is used independently, copy the license here.
 */

package wombat.util.files;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.io.IOException;
import java.util.Stack;

import javax.swing.JMenu;
import javax.swing.JMenuItem;

import wombat.util.OS;
import wombat.util.errors.ErrorManager;

/**
 * Remember recently opened documents.
 */
public class RecentDocumentManager {
	private RecentDocumentManager() {}

	// How many document we're going to deal with.
	static int FileCount = 10;
	
	// The actual files that were opened.
	static Stack<File> fileList = new Stack<File>();
	
	// The menu containing a list of recently opened files.
	static JMenu menu;
	
	/**
	 * Add a new file.
	 * @param f The file to add/remove.
	 */
	public static void addFile(File f) {
		// Try to make it canonical to avoid removing duplicates.
		try {
			f = f.getCanonicalFile();
		} catch (IOException e) {
		}
		
		// If it already existed, use remove to bump it to the front of the list.
		fileList.remove(f);
		fileList.push(f);

		// Old documents fall off.
		while (fileList.size() > FileCount)
			fileList.remove(0);
		
		// Rebuild the menu.
		rebuildMenu();
	}
	
	/**
	 * Rebuild the menu.
	 */
	static void rebuildMenu() {
		if (menu != null) {
			// Clear the old items out.
			menu.removeAll();
			
			// Go through the item list, remove any that no longer exist, add the rest to the menu.
			JMenuItem item;
			int j = 1;
			for (int i = fileList.size() - 1; i >= 0; i--) {
				final File each = fileList.get(i);
				
				if (!each.exists()) {
					fileList.remove(i);
					continue;
				}
				
				// Add to the menu with a shortcut for each.
				item = new JMenuItem(j + " - " + each.getPath());
				item.setMnemonic(("" + j).charAt(0));
				item.addActionListener(new ActionListener() {
					@Override
					public void actionPerformed(ActionEvent e) {
						DocumentManager.Open(each);
					}
				});
				menu.add(item);
				j += 1;
			}
			
			// Add a final option to clear this list.
			menu.addSeparator();
			item = new JMenuItem("Clear recent documents");
			item.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					fileList.clear();
					rebuildMenu();
				}
			});
			menu.add(item);
			
			// Figure out if it should be enabled or disabled.
			menu.setVisible(!fileList.isEmpty());
		}
	}

	/**
	 * Build a list that keeps track of recent documents.
	 * @return
	 */
	public static JMenuItem buildRecentDocumentsMenu() {
		// Build the menu if it hasn't already been.
		if (menu == null) {
			menu = new JMenu("Open recent");
			if (!OS.IsOSX) menu.setMnemonic('r');
			rebuildMenu();
		}
		
		return menu;
	}

	/**
	 * Set the files to a string.
	 */
	public static void setFiles(String files) {
		if (files != null) {
			for (String doc : files.split(";")) {
				if (!doc.trim().isEmpty()) {
					try {
						fileList.add(new File(doc).getCanonicalFile());
					} catch(IOException ex) {
						ErrorManager.logError("Unable to find canonical path for '" + doc.toString() + "' when loading recent documents");
					}
				}
			}
		}
		
		rebuildMenu();
	}
	
	/**
	 * Get the files as a string.
	 * @return Duh
	 */
	public static String getFiles() {
		StringBuilder sb = new StringBuilder();
		for (File f : fileList) {
			try {
				sb.append(f.getCanonicalPath());
				sb.append(";");
			} catch(IOException ex) {
				ErrorManager.logError("Unable to find canonical path for '" + f.toString() + "' when saving recent documents");
			}
		}
		if (sb.length() > 0)
			sb.delete(sb.length() - 1, sb.length());
		return sb.toString();
	}
}