/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * The contents of this file are subject to the Netscape Public
 * License Version 1.1 (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.mozilla.org/NPL/
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code is mozilla.org code.
 *
 * The Initial Developer of the Original Code is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1999 Netscape Communications Corporation. All
 * Rights Reserved.
 *
 * Contributor(s): 
 */

package com.netscape.jndi.ldap;

import javax.naming.*;
import javax.naming.directory.*;
import javax.naming.spi.*;
import netscape.ldap.*;
import netscape.ldap.util.*;
import java.io.*;
import java.util.*;
import com.netscape.jndi.ldap.common.Debug;

/**
 * Class used to map Java objects to ldap entries back and forth
*/
public class ObjectMapper {

    /**
     * Schema object classes for mapping java objects to ldap entries
     */
    static final String OC_JAVAOBJECT = "javaObject";  // abstract oc
    static final String OC_SERIALOBJ  = "javaSerializedObject";//aux oc
    static final String OC_MARSHALOBJ = "javaMarshalledObject";//aux oc   
    static final String OC_REFERENCE  = "javaNamingReference"; //aux oc
    //static final String OC_REMOTEOBJ  = "javaRemoteObject";    //aux oc, depricated
    static final String OC_CONTAINER  = "javaContainer";  //structural oc

    /**
     * Schema attributes for mapping java objects to ldap entries
     */
    static final String AT_CLASSNAME   = "javaClassName";         //required
    static final String AT_CLASSNAMES  = "javaClassNames";       //optional 
    static final String AT_DESCRIPTION = "description";          //optional  
    static final String AT_JAVADOC     = "javaDoc";              //optional   
    static final String AT_CODEBASE    = "javaCodeBase";         //optional
    static final String AT_SERIALDATA  = "javaSerializedData";   //required
    static final String AT_REFADDR     = "javaReferenceAddress"; //optional
    static final String AT_OBJFACTORY  = "javaFactory";          //optional 
    //static final String AT_REMOTELOC   = "javaRemoteLocation";   //required, depricated
    
    //Default Object class for NameClassPair
    static final String DEFAULT_OBJCLASS = "javax.naming.directory.DirContext";
    
    static Object entryToObject(LDAPEntry entry, LdapContextImpl ctx) throws NamingException {
        Object obj = entryToObject(entry);
        if (obj == null) {
            obj = new LdapContextImpl(entry.getDN(), ctx);
        }    

        // SP is required to contact the DirectoryManager first to obtain an object 
        try {
            String relName = LdapNameParser.getRelativeName(ctx.m_ctxDN, entry.getDN());
            Name nameObj = LdapNameParser.getParser().parse(relName);
            Attributes attrs = new AttributesImpl(entry.getAttributeSet(),
                                                  ctx.m_ctxEnv.getUserDefBinaryAttrs());
            obj = DirectoryManager.getObjectInstance(obj, nameObj, ctx, ctx.getEnvironment(), attrs);
        }
        catch (Exception ex) {
            if (ex instanceof NamingException) {
                throw (NamingException)ex;
            }
            NamingException nameEx = new NamingException("NamingManager.getObjectInstance failed");
            nameEx.setRootCause(ex);
            throw nameEx;
        }
        
        return obj;

    }

    /**
     * Convert a Ldap entry into a java object
     */
    static Object entryToObject(LDAPEntry entry) throws NamingException {
                
        try { 
            LDAPAttributeSet attrs = entry.getAttributeSet();
        
            // TODO javaCodeBase to be processed
            
            LDAPAttribute attr = null;
            if ((attr = attrs.getAttribute(AT_SERIALDATA)) != null) {
                byte[] serdata = (byte[])attr.getByteValues().nextElement();
                return deserializeObject(serdata);
            }
            
            // Reference
            else if ((attr = attrs.getAttribute(AT_REFADDR)) != null) {
                return decodeRefObj(attrs);
            }
                        
            return null;
        }
        catch (Exception ex) {
            if (ex instanceof NamingException) {
                throw (NamingException)ex;
            }
            NamingException nameEx = new NamingException("NamingManager.getStateToStore failed");
            nameEx.setRootCause(ex);
            throw nameEx;
        }    
    }

    /**
     * Get the className for NameClassPair from an entry
     */
    static String getClassName(LDAPEntry entry) {
        LDAPAttributeSet attrs = entry.getAttributeSet();
        LDAPAttribute attrClass = attrs.getAttribute(AT_CLASSNAME);
        if (attrClass != null) {
            String className = (String)attrClass.getStringValues().nextElement();
            return className;
        }    
        return DEFAULT_OBJCLASS;
    }
    

    /**
     * Convert a java object with an optional set of attributes into a LDAP entry
     */
    static LDAPAttributeSet objectToAttrSet(Object obj, String name, LdapContextImpl ctx,  Attributes attrs) throws NamingException {
    
        // SP is required to contact the DirectoryManager first to obtain a state object 
        try {
            Name nameObj = LdapNameParser.getParser().parse(name);
            DirStateFactory.Result stb = DirectoryManager.getStateToBind(obj, nameObj, ctx, ctx.getEnvironment(), attrs);
            obj = stb.getObject();
            attrs = stb.getAttributes();
        }
        catch (Exception ex) {
            if (ex instanceof NamingException) {
                throw (NamingException)ex;
            }
            NamingException nameEx = new NamingException("NamingManager.getStateToStore failed");
            nameEx.setRootCause(ex);
            throw nameEx;
        }

        if (obj == null) {
            return AttributesImpl.jndiAttrsToLdapAttrSet(attrs);
        }    
        else if (attrs == null) {
            attrs = new BasicAttributes(/*ignoreCase=*/true);
        }    

        Attribute objectclass = attrs.get("objectClass");
        if (objectclass == null) {
            objectclass = attrs.get("objectclass"); // try lower case
        }
        if (objectclass == null) {
            objectclass = new BasicAttribute("objectClass", "top");
            objectclass.add(OC_CONTAINER);
            attrs.put(objectclass);
        }
        
        // Root object class
        objectclass.add(OC_JAVAOBJECT);

        if (obj instanceof Reference) {
            objectclass.add(OC_REFERENCE);
            char delimChar = ctx.m_ctxEnv.getRefSeparator();
            attrs = encodeRefObj(delimChar, (Reference)obj, attrs);
        }
        
        else if (obj instanceof Referenceable) {
            objectclass.add(OC_REFERENCE);
            char delimChar = ctx.m_ctxEnv.getRefSeparator();
            attrs = encodeRefObj(delimChar, ((Referenceable)obj).getReference(), attrs);
        }
        
        else if (obj instanceof Serializable) {
            if (objectclass.contains(OC_MARSHALOBJ)) {
                ; // do nothing
            }
            else if (objectclass.contains(OC_MARSHALOBJ.toLowerCase())) {
                ; // do nothing
            }
            else {
                objectclass.add(OC_SERIALOBJ);
            }                
            attrs = encodeSerialObj((Serializable)obj , attrs);
        }
        
        else if (obj instanceof DirContext) {
            attrs = encodeDirCtxObj((DirContext)obj , attrs);
        }
        
        else {
            throw new NamingException("Can not bind object of type " +
                  obj.getClass().getName());
        }    
            
        return AttributesImpl.jndiAttrsToLdapAttrSet(attrs);
    }    

    /**
     * Deserialized object, create object from a stream of bytes
     */
    private static Object deserializeObject(byte[] byteBuf) throws NamingException {
    
        ByteArrayInputStream bis = null;
        ObjectInputStream  objis = null;

        try {
            bis   = new ByteArrayInputStream(byteBuf);
            objis = new ObjectInputStream(bis);
            return objis.readObject();
        }
        catch(Exception ex) {
            NamingException nameEx = new NamingException("Failed to deserialize object");
            nameEx.setRootCause(ex);
            throw nameEx;
        }
        finally {
            try {
                if (objis != null) {
                    objis.close();
                }
                if (bis != null) {
                    bis.close();
                }
            }
            catch (Exception ex) {}
        }
    }


    /**
     * Serialize object, convert object to a stream of bytes
     */
    private static byte[] serializeObject(Object obj) throws NamingException {

        ByteArrayOutputStream bos = null;
        ObjectOutputStream  objos = null;

        try {
            bos   = new ByteArrayOutputStream();
            objos = new ObjectOutputStream(bos);
            objos.writeObject(obj);
            objos.flush();
            return bos.toByteArray();
        }
        catch(Exception ex) {
            NamingException nameEx = new NamingException("Failed to serialize object");
            nameEx.setRootCause(ex);
            throw nameEx;
        }
        finally {
            try {
                if (objos != null) {
                    objos.close();
                }
                if (bos != null) {
                    bos.close();
                }
            }
            catch (Exception ex) {}
        }
    }    

    /**
     * Decode Jndi Reference Object
     */
    private static Reference decodeRefObj(LDAPAttributeSet attrs) throws NamingException {        
        try {

            LDAPAttribute attr = null;
            String className=null, factory = null, factoryLoc = null; 
            if ((attr = attrs.getAttribute(AT_CLASSNAME)) == null ) {
                throw new NamingException("Bad Reference encoding, no attribute " + AT_CLASSNAME);
            }    
            className = (String)attr.getStringValues().nextElement();
            
            if ((attr = attrs.getAttribute(AT_OBJFACTORY)) != null ) {
                factory = (String)attr.getStringValues().nextElement();
            }    
            if ((attr = attrs.getAttribute(AT_CODEBASE)) != null ) {
                factoryLoc = (String)attr.getStringValues().nextElement();
            }    

            Reference ref = new Reference(className, factory, factoryLoc);
            
            if ((attr = attrs.getAttribute(AT_REFADDR)) == null ) {
                return ref; // no refAddr
            }    

            for (Enumeration e = attr.getStringValues(); e.hasMoreElements();) {
                decodeRefAddr((String)e.nextElement(), ref);
            }
            
            return ref;
        }    
        catch (Exception ex) {
            if (ex instanceof NamingException) {
                throw (NamingException)ex;
            }
            NamingException nameEx = new NamingException("NamingManager.getStateToStore failed");
            nameEx.setRootCause(ex);
            throw nameEx;
        }    
    }

    /**
     * Decode RefAddr according to the <draft-ryan-java-schema-01.rev.txt>
     * StringRefAddr are encoded as #posNo#refType#refValue where posNo is the 
     * refAddr position (index) inside a rerference. BynaryRefAddr is encoded
     * as #posNo#refType##data where data is the base64 encoding of the serialized
     * form of the entire BinaryRefAddr instance.
     */    
    private static void decodeRefAddr(String enc, Reference ref) throws NamingException{
        
        if (enc.length() == 0) {
            throw new NamingException("Bad Reference encoding, empty refAddr");
        }
        
        String delimChar = enc.substring(0,1);
        
        StringTokenizer tok = new StringTokenizer(enc, delimChar);
        
        int tokCount = tok.countTokens();
        if (tokCount != 3 && tokCount != 4)  {
            Debug.println(3, "enc=" + enc + " delimChar="+delimChar + " tokCount="+tokCount);
            throw new NamingException("Bad Reference encoding");
        }
        
        String type = null;
        int posn = -1;
        for (int i = 0; i < tokCount; i++)    {
            String s = tok.nextToken();
        
            if (i == 0) { // position
                try {
                    posn = Integer.parseInt(s);
                }
                catch (Exception e) {
                    throw new NamingException("Bad Reference encoding, refAddr position not an initger");
                }
            }
            
            else if (i == 1) { // type
                if (s.length() == 0) {
                    throw new NamingException("Bad Reference encoding, empty refAddr type");
                }
                type = s;
            }
            
            else if (i == 2) { // value for StringRefAddr, empty for BinaryRefAddr
                if (s.length() == 0 && tokCount != 4) { // should be empty for binary refs
                    throw new NamingException("Bad Reference encoding, empty refAddr string value");
                }
                ref.add(posn, new StringRefAddr(type, s));
            }
            
            else { // base64 encoding of the serialized BinaryRefAddr
                if (s.length() == 0) {
                    throw new NamingException("Bad Reference encoding, empty refAddr binary value");
                }
                MimeBase64Decoder base64Dec = new MimeBase64Decoder();
                ByteBuf in  = new ByteBuf(s), out = new ByteBuf();
                base64Dec.translate(in, out);
                base64Dec.eof(out);
                ref.add(posn, (RefAddr) deserializeObject(out.toBytes()));
            }
        }
    }    


    /**
     * Encode Jndi Reference Object
     */
    private static Attributes encodeRefObj(char delimChar, Reference ref, Attributes attrs) throws NamingException {
        
        if (ref.getClassName() != null) {
            attrs.put(new BasicAttribute(AT_CLASSNAME, ref.getClassName()));
        }
        if (ref.getFactoryClassName() != null) {
            attrs.put(new BasicAttribute(AT_OBJFACTORY, ref.getFactoryClassName()));
        }    
        if (ref.getFactoryClassLocation() != null) {
            attrs.put(new BasicAttribute(AT_CODEBASE, ref.getFactoryClassLocation()));
        }    

        if(ref.size() > 0) {
            BasicAttribute refAttr = new BasicAttribute(AT_REFADDR);
            for(int i = 0; i < ref.size(); i++) {
                refAttr.add(encodeRefAddr(delimChar, i, ref.get(i)));
            }
            attrs.put(refAttr);
        }
        return attrs;
    }

    /**
     * Encode RefAddr according to the <draft-ryan-java-schema-01.rev.txt>
     * StringRefAddr are encoded as #posNo#refType#refValue where posNo is the 
     * refAddr position (index) inside a rerference. BynaryRefAddr is encoded
     * as #posNo#refType##data where data is the base64 encoding of the serialized
     * form of the entire BinaryRefAddr instance.

     */    
    private static String encodeRefAddr(char delimChar, int idx, RefAddr refAddr) throws NamingException{
        
        if(refAddr instanceof StringRefAddr) {

            String content = (String) refAddr.getContent();
            if (content != null && content.length() > 0 && content.charAt(0) == delimChar) {
                throw new NamingException(
                "Can not encode StringRefAddr, value starts with the delimiter character " + delimChar);
            }    
            return delimChar + idx +
                   delimChar + refAddr.getType() +
                   delimChar + content;
        }
        
        else { // BinaryRefAdd
        
            byte[] serialRefAddr = serializeObject(refAddr);
            MimeBase64Encoder base64 = new MimeBase64Encoder();
            ByteBuf in  = new ByteBuf(), out = new ByteBuf();
            in.append(serialRefAddr);
            base64.translate(in, out);
            base64.eof(out);
            return delimChar + idx +
                   delimChar + refAddr.getType() +
                   delimChar + delimChar + out.toString();
        }
    }
    
    
    /**
     * Encode Serializable object
     */
     
     static Attributes encodeSerialObj(Serializable obj, Attributes attrs) throws NamingException{
        if (attrs.get(AT_CLASSNAME) == null) {
            attrs.put(new BasicAttribute(AT_CLASSNAME, obj.getClass().getName()));
        }
        attrs.put(new BasicAttribute(AT_SERIALDATA, serializeObject(obj)));
        return attrs;
     }
     
    /**
     * Encode DirContext object (merege attributes)
     */
    static Attributes encodeDirCtxObj(DirContext obj, Attributes attrs) throws NamingException{
        Attributes ctxAttrs = obj.getAttributes("");
        for (NamingEnumeration enum = ctxAttrs.getAll(); enum.hasMore();) {
            attrs.put((Attribute)enum.next());
        }
        return attrs;
    }
    
    public static void main(String[] args) {
            byte[] serialRefAddr = { (byte)'a', (byte)'0', (byte)'A', (byte)0x10, (byte)0x7f, (byte)0xaa };
            MimeBase64Encoder base64 = new MimeBase64Encoder();
            MimeBase64Decoder base64Dec = new MimeBase64Decoder();
            ByteBuf in  = new ByteBuf(), out = new ByteBuf();
            in.append(serialRefAddr);
            base64.translate(in, out);
            base64.eof(out);
            System.err.println("in="+in);
            System.err.println("out="+out);
            in  = new ByteBuf(out.toString());
            out = new ByteBuf();
            base64Dec.translate(in, out);
            base64Dec.eof(out);
            System.err.println("in="+in);
            System.err.println("out="+out);
            
    }
}