/*

 * 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.naming.resources;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Date;

import java.util.Hashtable;

import javax.naming.NameAlreadyBoundException;

import javax.naming.NamingEnumeration;

import javax.naming.NamingException;

import javax.naming.OperationNotSupportedException;

import javax.naming.directory.Attributes;

import javax.naming.directory.DirContext;

import javax.naming.directory.ModificationItem;

import javax.naming.directory.SearchControls;

import org.apache.catalina.util.RequestUtil;

import org.apache.naming.NamingContextBindingsEnumeration;

import org.apache.naming.NamingContextEnumeration;

import org.apache.naming.NamingEntry;

/**

 * Filesystem Directory Context implementation helper class.

 *

 * @author Remy Maucherat

 */

public class FileDirContext extends BaseDirContext {

    private static org.apache.juli.logging.Log log=

        org.apache.juli.logging.LogFactory.getLog( FileDirContext.class );

    // -------------------------------------------------------------- Constants

    /**

     * The descriptive information string for this implementation.

     */

    protected static final int BUFFER_SIZE = 2048;

    // ----------------------------------------------------------- Constructors

    /**

     * Builds a file directory context using the given environment.

     */

    public FileDirContext() {

        super();

    }

    /**

     * Builds a file directory context using the given environment.

     */

    public FileDirContext(Hashtable env) {

        super(env);

    }

    // ----------------------------------------------------- Instance Variables

    /**

     * The document base directory.

     */

    protected File base = null;

    /**

     * Absolute normalized filename of the base.

     */

    protected String absoluteBase = null;

    /**

     * Case sensitivity.

     */

    protected boolean caseSensitive = true;

    /**

     * Allow linking.

     */

    protected boolean allowLinking = false;

    // ------------------------------------------------------------- Properties

    /**

     * Set the document root.

     *

     * @param docBase The new document root

     *

     * @exception IllegalArgumentException if the specified value is not

     *  supported by this implementation

     * @exception IllegalArgumentException if this would create a

     *  malformed URL

     */

    public void setDocBase(String docBase) {

    // Validate the format of the proposed document root

    if (docBase == null)

        throw new IllegalArgumentException

        (sm.getString("resources.null"));

    // Calculate a File object referencing this document base directory

    base = new File(docBase);

        try {

            base = base.getCanonicalFile();

        } catch (IOException e) {

            // Ignore

        }

    // Validate that the document base is an existing directory

    if (!base.exists() || !base.isDirectory() || !base.canRead())

        throw new IllegalArgumentException

        (sm.getString("fileResources.base", docBase));

        this.absoluteBase = base.getAbsolutePath();

        super.setDocBase(docBase);

    }

    /**

     * Set case sensitivity.

     */

    public void setCaseSensitive(boolean caseSensitive) {

        this.caseSensitive = caseSensitive;

    }

    /**

     * Is case sensitive ?

     */

    public boolean isCaseSensitive() {

        return caseSensitive;

    }

    /**

     * Set allow linking.

     */

    public void setAllowLinking(boolean allowLinking) {

        this.allowLinking = allowLinking;

    }

    /**

     * Is linking allowed.

     */

    public boolean getAllowLinking() {

        return allowLinking;

    }

    // --------------------------------------------------------- Public Methods

    /**

     * Release any resources allocated for this directory context.

     */

    public void release() {

        super.release();

    }

    // -------------------------------------------------------- Context Methods

    /**

     * Retrieves the named object.

     *

     * @param name the name of the object to look up

     * @return the object bound to name

     * @exception NamingException if a naming exception is encountered

     */

    public Object lookup(String name)

        throws NamingException {

        Object result = null;

        File file = file(name);

        if (file == null)

            throw new NamingException

                (sm.getString("resources.notFound", name));

        if (file.isDirectory()) {

            FileDirContext tempContext = new FileDirContext(env);

            tempContext.setDocBase(file.getPath());

            tempContext.setAllowLinking(getAllowLinking());

            tempContext.setCaseSensitive(isCaseSensitive());

            result = tempContext;

        } else {

            result = new FileResource(file);

        }

        return result;

    }

    /**

     * Unbinds the named object. Removes the terminal atomic name in name

     * from the target context--that named by all but the terminal atomic

     * part of name.

     * <p>

     * This method is idempotent. It succeeds even if the terminal atomic

     * name is not bound in the target context, but throws

     * NameNotFoundException if any of the intermediate contexts do not exist.

     *

     * @param name the name to bind; may not be empty

     * @exception NameNotFoundException if an intermediate context does not

     * exist

     * @exception NamingException if a naming exception is encountered

     */

    public void unbind(String name)

        throws NamingException {

        File file = file(name);

        if (file == null)

            throw new NamingException

                (sm.getString("resources.notFound", name));

        if (!file.delete())

            throw new NamingException

                (sm.getString("resources.unbindFailed", name));

    }

    /**

     * Binds a new name to the object bound to an old name, and unbinds the

     * old name. Both names are relative to this context. Any attributes

     * associated with the old name become associated with the new name.

     * Intermediate contexts of the old name are not changed.

     *

     * @param oldName the name of the existing binding; may not be empty

     * @param newName the name of the new binding; may not be empty

     * @exception NameAlreadyBoundException if newName is already bound

     * @exception NamingException if a naming exception is encountered

     */

    public void rename(String oldName, String newName)

        throws NamingException {

        File file = file(oldName);

        if (file == null)

            throw new NamingException

                (sm.getString("resources.notFound", oldName));

        File newFile = new File(base, newName);

        file.renameTo(newFile);

    }

    /**

     * Enumerates the names bound in the named context, along with the class

     * names of objects bound to them. The contents of any subcontexts are

     * not included.

     * <p>

     * If a binding is added to or removed from this context, its effect on

     * an enumeration previously returned is undefined.

     *

     * @param name the name of the context to list

     * @return an enumeration of the names and class names of the bindings in

     * this context. Each element of the enumeration is of type NameClassPair.

     * @exception NamingException if a naming exception is encountered

     */

    public NamingEnumeration list(String name)

        throws NamingException {

        File file = file(name);

        if (file == null)

            throw new NamingException

                (sm.getString("resources.notFound", name));

        return new NamingContextEnumeration(list(file).iterator());

    }

    /**

     * Enumerates the names bound in the named context, along with the

     * objects bound to them. The contents of any subcontexts are not

     * included.

     * <p>

     * If a binding is added to or removed from this context, its effect on

     * an enumeration previously returned is undefined.

     *

     * @param name the name of the context to list

     * @return an enumeration of the bindings in this context.

     * Each element of the enumeration is of type Binding.

     * @exception NamingException if a naming exception is encountered

     */

    public NamingEnumeration listBindings(String name)

        throws NamingException {

        File file = file(name);

        if (file == null)

            throw new NamingException

                (sm.getString("resources.notFound", name));

        return new NamingContextBindingsEnumeration(list(file).iterator(),

                this);

    }

    /**

     * Destroys the named context and removes it from the namespace. Any

     * attributes associated with the name are also removed. Intermediate

     * contexts are not destroyed.

     * <p>

     * This method is idempotent. It succeeds even if the terminal atomic

     * name is not bound in the target context, but throws

     * NameNotFoundException if any of the intermediate contexts do not exist.

     *

     * In a federated naming system, a context from one naming system may be

     * bound to a name in another. One can subsequently look up and perform

     * operations on the foreign context using a composite name. However, an

     * attempt destroy the context using this composite name will fail with

     * NotContextException, because the foreign context is not a "subcontext"

     * of the context in which it is bound. Instead, use unbind() to remove

     * the binding of the foreign context. Destroying the foreign context

     * requires that the destroySubcontext() be performed on a context from

     * the foreign context's "native" naming system.

     *

     * @param name the name of the context to be destroyed; may not be empty

     * @exception NameNotFoundException if an intermediate context does not

     * exist

     * @exception NotContextException if the name is bound but does not name

     * a context, or does not name a context of the appropriate type

     */

    public void destroySubcontext(String name)

        throws NamingException {

        unbind(name);

    }

    /**

     * Retrieves the named object, following links except for the terminal

     * atomic component of the name. If the object bound to name is not a

     * link, returns the object itself.

     *

     * @param name the name of the object to look up

     * @return the object bound to name, not following the terminal link

     * (if any).

     * @exception NamingException if a naming exception is encountered

     */

    public Object lookupLink(String name)

        throws NamingException {

        // Note : Links are not supported

        return lookup(name);

    }

    /**

     * Retrieves the full name of this context within its own namespace.

     * <p>

     * Many naming services have a notion of a "full name" for objects in

     * their respective namespaces. For example, an LDAP entry has a

     * distinguished name, and a DNS record has a fully qualified name. This

     * method allows the client application to retrieve this name. The string

     * returned by this method is not a JNDI composite name and should not be

     * passed directly to context methods. In naming systems for which the

     * notion of full name does not make sense,

     * OperationNotSupportedException is thrown.

     *

     * @return this context's name in its own namespace; never null

     * @exception OperationNotSupportedException if the naming system does

     * not have the notion of a full name

     * @exception NamingException if a naming exception is encountered

     */

    public String getNameInNamespace()

        throws NamingException {

        return docBase;

    }

    // ----------------------------------------------------- DirContext Methods

    /**

     * Retrieves selected attributes associated with a named object.

     * See the class description regarding attribute models, attribute type

     * names, and operational attributes.

     *

     * @return the requested attributes; never null

     * @param name the name of the object from which to retrieve attributes

     * @param attrIds the identifiers of the attributes to retrieve. null

     * indicates that all attributes should be retrieved; an empty array

     * indicates that none should be retrieved

     * @exception NamingException if a naming exception is encountered

     */

    public Attributes getAttributes(String name, String[] attrIds)

        throws NamingException {

        // Building attribute list

        File file = file(name);

        if (file == null)

            throw new NamingException

                (sm.getString("resources.notFound", name));

        return new FileResourceAttributes(file);

    }

    /**

     * Modifies the attributes associated with a named object. The order of

     * the modifications is not specified. Where possible, the modifications

     * are performed atomically.

     *

     * @param name the name of the object whose attributes will be updated

     * @param mod_op the modification operation, one of: ADD_ATTRIBUTE,

     * REPLACE_ATTRIBUTE, REMOVE_ATTRIBUTE

     * @param attrs the attributes to be used for the modification; may not

     * be null

     * @exception AttributeModificationException if the modification cannot be

     * completed successfully

     * @exception NamingException if a naming exception is encountered

     */

    public void modifyAttributes(String name, int mod_op, Attributes attrs)

        throws NamingException {

    }

    /**

     * Modifies the attributes associated with a named object using an an

     * ordered list of modifications. The modifications are performed in the

     * order specified. Each modification specifies a modification operation

     * code and an attribute on which to operate. Where possible, the

     * modifications are performed atomically.

     *

     * @param name the name of the object whose attributes will be updated

     * @param mods an ordered sequence of modifications to be performed; may

     * not be null

     * @exception AttributeModificationException if the modification cannot be

     * completed successfully

     * @exception NamingException if a naming exception is encountered

     */

    public void modifyAttributes(String name, ModificationItem[] mods)

        throws NamingException {

    }

    /**

     * Binds a name to an object, along with associated attributes. If attrs

     * is null, the resulting binding will have the attributes associated

     * with obj if obj is a DirContext, and no attributes otherwise. If attrs

     * is non-null, the resulting binding will have attrs as its attributes;

     * any attributes associated with obj are ignored.

     *

     * @param name the name to bind; may not be empty

     * @param obj the object to bind; possibly null

     * @param attrs the attributes to associate with the binding

     * @exception NameAlreadyBoundException if name is already bound

     * @exception InvalidAttributesException if some "mandatory" attributes

     * of the binding are not supplied

     * @exception NamingException if a naming exception is encountered

     */

    public void bind(String name, Object obj, Attributes attrs)

        throws NamingException {

        // Note: No custom attributes allowed

        File file = new File(base, name);

        if (file.exists())

            throw new NameAlreadyBoundException

                (sm.getString("resources.alreadyBound", name));

        rebind(name, obj, attrs);

    }

    /**

     * Binds a name to an object, along with associated attributes,

     * overwriting any existing binding. If attrs is null and obj is a

     * DirContext, the attributes from obj are used. If attrs is null and obj

     * is not a DirContext, any existing attributes associated with the object

     * already bound in the directory remain unchanged. If attrs is non-null,

     * any existing attributes associated with the object already bound in

     * the directory are removed and attrs is associated with the named

     * object. If obj is a DirContext and attrs is non-null, the attributes

     * of obj are ignored.

     *

     * @param name the name to bind; may not be empty

     * @param obj the object to bind; possibly null

     * @param attrs the attributes to associate with the binding

     * @exception InvalidAttributesException if some "mandatory" attributes

     * of the binding are not supplied

     * @exception NamingException if a naming exception is encountered

     */

    public void rebind(String name, Object obj, Attributes attrs)