/*
 * @(#)FileSystemView.java	1.43 04/01/13
 *
 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
 * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

package javax.swing.filechooser;


import javax.swing.event.*;
import javax.swing.*;

import java.awt.Image;
import java.io.File;
import java.io.FileFilter;
import java.io.FilenameFilter;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Vector;

import java.lang.reflect.*;

import sun.awt.shell.*;

/**
 * FileSystemView is JFileChooser's gateway to the
 * file system. Since the JDK1.1 File API doesn't allow
 * access to such information as root partitions, file type
 * information, or hidden file bits, this class is designed
 * to intuit as much OS-specific file system information as
 * possible.
 *
 * <p>
 *
 * Java Licensees may want to provide a different implementation of
 * FileSystemView to better handle a given operating system.
 *
 * @version 1.43 01/13/04
 * @author Jeff Dinkins
 */

// PENDING(jeff) - need to provide a specification for
// how Mac/OS2/BeOS/etc file systems can modify FileSystemView
// to handle their particular type of file system.

public abstract class FileSystemView {

    static FileSystemView windowsFileSystemView = null;
    static FileSystemView unixFileSystemView = null;
    //static FileSystemView macFileSystemView = null;
    static FileSystemView genericFileSystemView = null;

    public static FileSystemView getFileSystemView() {
	if(File.separatorChar == '\\') {
	    if(windowsFileSystemView == null) {
		windowsFileSystemView = new WindowsFileSystemView();
	    }
	    return windowsFileSystemView;
	}

	if(File.separatorChar == '/') {
	    if(unixFileSystemView == null) {
		unixFileSystemView = new UnixFileSystemView();
	    }
	    return unixFileSystemView;
	}

	// if(File.separatorChar == ':') {
	//    if(macFileSystemView == null) {
	//	macFileSystemView = new MacFileSystemView();
	//    }
	//    return macFileSystemView;
	//}

	if(genericFileSystemView == null) {
	    genericFileSystemView = new GenericFileSystemView();
	}
	return genericFileSystemView;
    }

    /**
     * Determines if the given file is a root in the navigatable tree(s).
     * Examples: Windows 98 has one root, the Desktop folder. DOS has one root
     * per drive letter, <code>C:\</code>, <code>D:\</code>, etc. Unix has one root,
     * the <code>"/"</code> directory.
     *
     * The default implementation gets information from the <code>ShellFolder</code> class.
     *
     * @param f a <code>File</code> object representing a directory
     * @return <code>true</code> if <code>f</code> is a root in the navigatable tree.
     * @see #isFileSystemRoot
     */
    public boolean isRoot(File f) {
	if (f == null || !f.isAbsolute()) {
	    return false;
	}

	File[] roots = getRoots();
	for (int i = 0; i < roots.length; i++) {
	    if (roots[i].equals(f)) {
		return true;
	    }
	}
	return false;
    }

    /**
     * Returns true if the file (directory) can be visited.
     * Returns false if the directory cannot be traversed.
     *
     * @param f the <code>File</code>
     * @return <code>true</code> if the file/directory can be traversed, otherwise <code>false</code>
     * @see JFileChooser#isTraversable
     * @see FileView#isTraversable
     */
    public Boolean isTraversable(File f) {
	return Boolean.valueOf(f.isDirectory());
    }

    /**
     * Name of a file, directory, or folder as it would be displayed in
     * a system file browser. Example from Windows: the "M:\" directory
     * displays as "CD-ROM (M:)"
     *
     * The default implementation gets information from the ShellFolder class.
     *
     * @param f a <code>File</code> object
     * @return the file name as it would be displayed by a native file chooser
     * @see JFileChooser#getName
     */
    public String getSystemDisplayName(File f) {
	String name = null;
	if (f != null) {
	    name = f.getName();
	    if (!name.equals("..") && !name.equals(".") &&
		((f instanceof ShellFolder) ||
		 f.exists())) {

		name = getShellFolder(f).getDisplayName();
		if (name == null || name.length() == 0) {
		    name = f.getPath();	// e.g. "/"
		}
	    }
	}
	return name;
    }

    /**
     * Type description for a file, directory, or folder as it would be displayed in
     * a system file browser. Example from Windows: the "Desktop" folder
     * is desribed as "Desktop".
     *
     * Override for platforms with native ShellFolder implementations.
     *
     * @param f a <code>File</code> object
     * @return the file type description as it would be displayed by a native file chooser
     * or null if no native information is available.
     * @see JFileChooser#getTypeDescription
     */
    public String getSystemTypeDescription(File f) {
	return null;
    }

    /**
     * Icon for a file, directory, or folder as it would be displayed in
     * a system file browser. Example from Windows: the "M:\" directory
     * displays a CD-ROM icon.
     *
     * The default implementation gets information from the ShellFolder class.
     *
     * @param f a <code>File</code> object
     * @return an icon as it would be displayed by a native file chooser
     * @see JFileChooser#getIcon
     */
    public Icon getSystemIcon(File f) {
	if (f != null) {
	    ShellFolder sf = getShellFolder(f);
	    Image img = sf.getIcon(false);
	    if (img != null) {
		return new ImageIcon(img, sf.getFolderType());
	    } else {
		return UIManager.getIcon(f.isDirectory() ? "FileView.directoryIcon" : "FileView.fileIcon");
	    }
	} else {
	    return null;
	}
    }

    /**
     * On Windows, a file can appear in multiple folders, other than its
     * parent directory in the filesystem. Folder could for example be the
     * "Desktop" folder which is not the same as file.getParentFile().
     *
     * @param folder a <code>File</code> object repesenting a directory or special folder
     * @param file a <code>File</code> object
     * @return <code>true</code> if <code>folder</code> is a directory or special folder and contains <code>file</code>.
     */
    public boolean isParent(File folder, File file) {
	if (folder == null || file == null) {
	    return false;
	} else if (folder instanceof ShellFolder) {
	    if (!ShellFolder.disableFileChooserSpeedFix()) {
		File parent = file.getParentFile();
		if (parent != null && parent.equals(folder)) {
		    return true;
		}
	    }
	    File[] children = getFiles(folder, false);
	    for (int i = 0; i < children.length; i++) {
		if (file.equals(children[i])) {
		    return true;
		}
	    }
	    return false;
	} else {
	    return folder.equals(file.getParentFile());
	}
    }

    /**
     *
     * @param parent a <code>File</code> object repesenting a directory or special folder
     * @param fileName a name of a file or folder which exists in <code>parent</code>
     * @return a File object. This is normally constructed with <code>new
     * File(parent, fileName)</code> except when parent and child are both
     * special folders, in which case the <code>File</code> is a wrapper containing
     * a <code>ShellFolder</code> object.
     */
    public File getChild(File parent, String fileName) {
	if (parent instanceof ShellFolder) {
	    File[] children = getFiles(parent, false);
	    for (int i = 0; i < children.length; i++) {
		if (children[i].getName().equals(fileName)) {
		    return children[i];
		}
	    }
	}
	return createFileObject(parent, fileName);
    }


    /**
     * Checks if <code>f</code> represents a real directory or file as opposed to a
     * special folder such as <code>"Desktop"</code>. Used by UI classes to decide if
     * a folder is selectable when doing directory choosing.
     *
     * @param f a <code>File</code> object
     * @return <code>true</code> if <code>f</code> is a real file or directory.
     */
    public boolean isFileSystem(File f) {
	if (f instanceof ShellFolder) {
	    return ((ShellFolder)f).isFileSystem();
	} else {
	    return true;
	}
    }

    /**
     * Creates a new folder with a default folder name.
     */
    public abstract File createNewFolder(File containingDir) throws IOException;

    /**
     * Returns whether a file is hidden or not.
     */
    public boolean isHiddenFile(File f) {
	return f.isHidden();
    }


    /**
     * Is dir the root of a tree in the file system, such as a drive
     * or partition. Example: Returns true for "C:\" on Windows 98.
     * 
     * @param f a <code>File</code> object representing a directory
     * @return <code>true</code> if <code>f</code> is a root of a filesystem
     * @see #isRoot
     */
    public boolean isFileSystemRoot(File dir) {
	return ShellFolder.isFileSystemRoot(dir);
    }

    /**
     * Used by UI classes to decide whether to display a special icon
     * for drives or partitions, e.g. a "hard disk" icon.
     *
     * The default implementation has no way of knowing, so always returns false.
     *
     * @param dir a directory
     * @return <code>false</code> always
     */
    public boolean isDrive(File dir) {
	return false;
    }

    /**
     * Used by UI classes to decide whether to display a special icon
     * for a floppy disk. Implies isDrive(dir).
     *
     * The default implementation has no way of knowing, so always returns false.
     *
     * @param dir a directory
     * @return <code>false</code> always
     */
    public boolean isFloppyDrive(File dir) {
	return false;
    }

    /**
     * Used by UI classes to decide whether to display a special icon
     * for a computer node, e.g. "My Computer" or a network server.
     *
     * The default implementation has no way of knowing, so always returns false.
     *
     * @param dir a directory
     * @return <code>false</code> always
     */
    public boolean isComputerNode(File dir) {
	return ShellFolder.isComputerNode(dir);
    }


    /**
     * Returns all root partitions on this system. For example, on
     * Windows, this would be the "Desktop" folder, while on DOS this
     * would be the A: through Z: drives.
     */
    public File[] getRoots() {
	// Don't cache this array, because filesystem might change
	File[] roots = (File[])ShellFolder.get("roots");

	for (int i = 0; i < roots.length; i++) {
	    if (isFileSystemRoot(roots[i])) {
		roots[i] = createFileSystemRoot(roots[i]);
	    }
	}
	return roots;
    }


    // Providing default implementations for the remaining methods
    // because most OS file systems will likely be able to use this
    // code. If a given OS can't, override these methods in its
    // implementation.

    public File getHomeDirectory() {
	return createFileObject(System.getProperty("user.home"));
    }

    /**
     * Return the user's default starting directory for the file chooser.
     *
     * @return a <code>File</code> object representing the default
     *         starting folder
     */
    public File getDefaultDirectory() {
	File f = (File)ShellFolder.get("fileChooserDefaultFolder");
	if (isFileSystemRoot(f)) {
	    f = createFileSystemRoot(f);
	}
	return f;
    }

    /**
     * Returns a File object constructed in dir from the given filename.
     */
    public File createFileObject(File dir, String filename) {
	if(dir == null) {
	    return new File(filename);
	} else {
	    return new File(dir, filename);
	}
    }

    /**
     * Returns a File object constructed from the given path string.
     */
    public File createFileObject(String path) {
	File f = new File(path);
	if (isFileSystemRoot(f)) {
	    f = createFileSystemRoot(f);
	}
	return f;
    }


    /**
     * Gets the list of shown (i.e. not hidden) files.
     */
    public File[] getFiles(File dir, boolean useFileHiding) {
	Vector files = new Vector();


	// add all files in dir
	File[] names;
	if (ShellFolder.disableFileChooserSpeedFix()) {
	    if (dir instanceof ShellFolder) {
		names = ((ShellFolder)dir).listFiles(!useFileHiding);
	    } else {
		names = dir.listFiles();
	    }
	} else {
	    if (!(dir instanceof ShellFolder)) {
		dir = getShellFolder(dir);
	    }

	    names = ((ShellFolder)dir).listFiles(!useFileHiding);
	}
	File f;

	int nameCount = (names == null) ? 0 : names.length;
	for (int i = 0; i < nameCount; i++) {
	    if (Thread.currentThread().isInterrupted()) {
		break;
	    }
	    f = names[i];
	    if (!(f instanceof ShellFolder)) {
		if (isFileSystemRoot(f)) {
		    f = createFileSystemRoot(f);
		}
		try {
		    f = ShellFolder.getShellFolder(f);
		} catch (FileNotFoundException e) {
		    // Not a valid file (wouldn't show in native file chooser)
		    // Example: C:\pagefile.sys
		    continue;
		} catch (InternalError e) {
		    // Not a valid file (wouldn't show in native file chooser)
		    // Example C:\Winnt\Profiles\joe\history\History.IE5
		    continue;
		}
	    }
	    if (!useFileHiding || !isHiddenFile(f)) {
		files.addElement(f);
	    }
	}

	return (File[])files.toArray(new File[files.size()]);
    }



    /**
     * Returns the parent directory of <code>dir</code>.
     * @param dir the <code>File</code> being queried
     * @return the parent directory of <code>dir</code>, or
     *   <code>null</code> if <code>dir</code> is <code>null</code>
     */
    public File getParentDirectory(File dir) {
	if (dir != null && dir.exists()) {
	    ShellFolder sf = getShellFolder(dir);
	    File psf = sf.getParentFile();
	    if (psf != null) {
		if (isFileSystem(psf)) {
		    File f = psf;
		    if (f != null && !f.exists()) {
			// This could be a node under "Network Neighborhood".
			File ppsf = psf.getParentFile();
			if (ppsf == null || !isFileSystem(ppsf)) {
			    // We're mostly after the exists() override for windows below.
			    f = createFileSystemRoot(f);
			}
		    }
		    return f;
		} else {
		    return psf;
		}
	    }
	}
	return null;
    }

    ShellFolder getShellFolder(File f) {
	if (!(f instanceof ShellFolder)
	    && !(f instanceof FileSystemRoot)
	    && isFileSystemRoot(f)) {

	    f = createFileSystemRoot(f);
	}
	try {
	    return ShellFolder.getShellFolder(f);
	} catch (FileNotFoundException e) {
	    System.err.println("FileSystemView.getShellFolder: f="+f);
	    e.printStackTrace();
	    return null;
	} catch (InternalError e) {
	    System.err.println("FileSystemView.getShellFolder: f="+f);
	    e.printStackTrace();
	    return null;
	}
    }

    /**
     * Creates a new <code>File</code> object for <code>f</code> with correct
     * behavior for a file system root directory.
     *
     * @param f a <code>File</code> object representing a file system root
     *		directory, for example "/" on Unix or "C:\" on Windows.
     * @return a new <code>File</code> object
     */
    protected File createFileSystemRoot(File f) {
	return new FileSystemRoot(f);
    }




    static class FileSystemRoot extends File {
	public FileSystemRoot(File f) {
	    super(f,"");
	}

	public FileSystemRoot(String s) {
	    super(s);
	}

	public boolean isDirectory() {
	    return true;
	}

	public String getName() {
	    return getPath();
	}
    }
}

/**
 * FileSystemView that handles some specific unix-isms.
 */
class UnixFileSystemView extends FileSystemView {

    private static final String newFolderString =
            UIManager.getString("FileChooser.other.newFolder");
    private static final String newFolderNextString  =
            UIManager.getString("FileChooser.other.newFolder.subsequent");

    /**
     * Creates a new folder with a default folder name.
     */
    public File createNewFolder(File containingDir) throws IOException {
	if(containingDir == null) {
	    throw new IOException("Containing directory is null:");
	}
	File newFolder = null;
	// Unix - using OpenWindows' default folder name. Can't find one for Motif/CDE.
	newFolder = createFileObject(containingDir, newFolderString);
	int i = 1;
	while (newFolder.exists() && (i < 100)) {
	    newFolder = createFileObject(containingDir, MessageFormat.format(
                    newFolderNextString, new Object[] { new Integer(i) }));
	    i++;
	}

	if(newFolder.exists()) {
	    throw new IOException("Directory already exists:" + newFolder.getAbsolutePath());
	} else {
	    newFolder.mkdirs();
	}

	return newFolder;
    }

    public boolean isFileSystemRoot(File dir) {
	return (dir != null && dir.getAbsolutePath().equals("/"));
    }

    public boolean isDrive(File dir) {
	if (isFloppyDrive(dir)) {
	    return true;
	} else {
	    return false;
	}
    }

    public boolean isFloppyDrive(File dir) {
	// Could be looking at the path for Solaris, but wouldn't be reliable.
	// For example:
	// return (dir != null && dir.getAbsolutePath().toLowerCase().startsWith("/floppy"));
	return false;
    }

    public boolean isComputerNode(File dir) {
	if (dir != null) {
	    String parent = dir.getParent();
	    if (parent != null && parent.equals("/net")) {
		return true;
	    }
	}
	return false;
    }
}


/**
 * FileSystemView that handles some specific windows concepts.
 */
class WindowsFileSystemView extends FileSystemView {

    private static final String newFolderString =
            UIManager.getString("FileChooser.win32.newFolder");
    private static final String newFolderNextString  =
            UIManager.getString("FileChooser.win32.newFolder.subsequent");

    public Boolean isTraversable(File f) {
	return Boolean.valueOf(isFileSystemRoot(f) || isComputerNode(f) || f.isDirectory());
    }

    public File getChild(File parent, String fileName) {
	if (fileName.startsWith("\\")
	    && !(fileName.startsWith("\\\\"))
	    && isFileSystem(parent)) {

	    //Path is relative to the root of parent's drive
	    String path = parent.getAbsolutePath();
	    if (path.length() >= 2
		&& path.charAt(1) == ':'
		&& Character.isLetter(path.charAt(0))) {

		return createFileObject(path.substring(0, 2) + fileName);
	    }
	}
	return super.getChild(parent, fileName);
    }

    /**
     * Type description for a file, directory, or folder as it would be displayed in
     * a system file browser. Example from Windows: the "Desktop" folder
     * is desribed as "Desktop".
     *
     * The Windows implementation gets information from the ShellFolder class.
     */
    public String getSystemTypeDescription(File f) {
	if (f != null) {
	    return getShellFolder(f).getFolderType();
	} else {
	    return null;
	}
    }

    /**
     * @return the Desktop folder.
     */
    public File getHomeDirectory() {
	return getRoots()[0];
    }

    /**
     * Creates a new folder with a default folder name.
     */
    public File createNewFolder(File containingDir) throws IOException {
	if(containingDir == null) {
	    throw new IOException("Containing directory is null:");
	}
	File newFolder = null;
	// Using NT's default folder name
	newFolder = createFileObject(containingDir, newFolderString);
	int i = 2;
	while (newFolder.exists() && (i < 100)) {
	    newFolder = createFileObject(containingDir, MessageFormat.format(
                newFolderNextString, new Object[] { new Integer(i) }));
	    i++;
	}

	if(newFolder.exists()) {
	    throw new IOException("Directory already exists:" + newFolder.getAbsolutePath());
	} else {
	    newFolder.mkdirs();
	}

	return newFolder;
    }

    public boolean isDrive(File dir) {
	return isFileSystemRoot(dir);
    }

    public boolean isFloppyDrive(File dir) {
	String path = dir.getAbsolutePath();
	return (path != null && (path.equals("A:\\") || path.equals("B:\\")));
    }

    /**
     * Returns a File object constructed from the given path string.
     */
    public File createFileObject(String path) {
	// Check for missing backslash after drive letter such as "C:" or "C:filename"
	if (path.length() >= 2 && path.charAt(1) == ':' && Character.isLetter(path.charAt(0))) {
	    if (path.length() == 2) {
		path += "\\";
	    } else if (path.charAt(2) != '\\') {
		path = path.substring(0, 2) + "\\" + path.substring(2);
	    }
	}
	return super.createFileObject(path);
    }

    protected File createFileSystemRoot(File f) {
	// Problem: Removable drives on Windows return false on f.exists()
	// Workaround: Override exists() to always return true.
	return new FileSystemRoot(f) {
	    public boolean exists() {
		return true;
	    }
	};
    }

}

/**
 * Fallthrough FileSystemView in case we can't determine the OS.
 */
class GenericFileSystemView extends FileSystemView {

    private static final String newFolderString =
            UIManager.getString("FileChooser.other.newFolder");

    /**
     * Creates a new folder with a default folder name.
     */
    public File createNewFolder(File containingDir) throws IOException {
	if(containingDir == null) {
	    throw new IOException("Containing directory is null:");
	}
	File newFolder = null;
	// Using NT's default folder name
	newFolder = createFileObject(containingDir, newFolderString);

	if(newFolder.exists()) {
	    throw new IOException("Directory already exists:" + newFolder.getAbsolutePath());
	} else {
	    newFolder.mkdirs();
	}

	return newFolder;
    }

}