/**************************************************************************
 * Path.java
 *
 * $Revision: 1.27 $
 * $Date: 2006/01/17 07:49:58 $
 *
 * Copyright (C) 2001 CERN - European Organization for Nuclear Research
 * All rights reserved.
 **************************************************************************/

package com.c2kernel.lookup;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.StringTokenizer;

import com.c2kernel.common.ObjectCannotBeUpdated;
import com.c2kernel.common.ObjectNotFoundException;
import com.c2kernel.process.Gateway;
import com.novell.ldap.LDAPAttributeSet;
import com.novell.ldap.LDAPConnection;
import com.novell.ldap.LDAPSearchConstraints;


/**
* @version $Revision: 1.27 $ $Date: 2006/01/17 07:49:58 $
* @author  $Author: abranson $
**/
public abstract class Path implements Serializable
{
    public static final String delim = "/";

    // types
    public static final short UNKNOWN = 0;
    public static final short CONTEXT = 1;
    public static final short ENTITY  = 2;

    // invalid int key
    public static final int   INVALID = -1;

    protected String[] mPath = new String[0];

    // slash delimited path
    protected String   mStringPath = null;
    // entity or context
    protected short    mType      = CONTEXT;
    // LDAP dn
    protected String   mDN        = null;
    // int syskey (only valid for entity SystemPaths)
    protected int      mSysKey    = INVALID;

    // ior is stored in here when it is resolved
    protected org.omg.CORBA.Object   mIOR         = null;
    //
    // needed for unusual subclass constructors

    protected static String mGlobalPath; //cern.ch
    protected static String mRootPath;   //cristal2
    protected static String mLocalPath;  //lab27

    public Path() {
    }

    /*
    * Creates an empty path
    */
    public Path(short type)
    {
        mType = type;
    }

    /*
    * Creates a path with an arraylist of the path (big endian)
    */
    public Path(String[] path, short type) {
        setPath(path);
        mType = type;
    }

    /*
     * Creates a path from a slash separated string (big endian)
    */
    public Path(String path, short type) {
        setPath(path);
        mType = type;
    }

    /*
     *  Create a path by appending a child string to an existing path
     */
    public Path(Path parent, String child, short type) {
        String[] oldPath = parent.getPath();
        mPath = new String[oldPath.length+1];
        for (int i=0; i<oldPath.length; i++)
            mPath[i] = oldPath[i];
        mPath[oldPath.length] = child;
        mType = type;
    }

     /*
      * Create a path by appending a child and inheriting the type
      */
    public Path(Path parent, String child) {
        this(parent, child, UNKNOWN);
    }
    /*************************************************************************/

    // Setters

    /* string array path e.g. { "Product", "Crystal", "Barrel", "2L", "331013013348" }
     * system/domain node ABSENT
    */
    public void setPath(String[] path)
    {
        mStringPath = null;
        mDN = null;
        mPath = path.clone();
        mSysKey = INVALID;
    }

    /* string path e.g. /system/d000/d000/d001
     * system/domain node PRESENT
    */
    public void setPath(String path)
    {
        ArrayList<String> newPath = new ArrayList<String>();
        StringTokenizer tok = new StringTokenizer(path, delim);
        if (tok.hasMoreTokens()) {
	        String first = tok.nextToken();
	        if (!first.equals(getRoot()))
	        	newPath.add(first);
	        while (tok.hasMoreTokens())
	            newPath.add(tok.nextToken());
        }

        mPath = (newPath.toArray(mPath));
        mStringPath = null;
        mDN = null;
        mSysKey = INVALID;
    }

    // lookup sets the IOR
    public void setIOR(org.omg.CORBA.Object IOR) {
        mIOR = IOR;
        if (IOR == null) mType = Path.CONTEXT;
        else mType = Path.ENTITY;
    }

    /* clone another path object
    */
    public void setPath(Path path)
    {
        mStringPath = null;
        mDN = null;
        mPath = (path.getPath().clone());
        mSysKey = INVALID;
    }

    /* LDAP dn e.g. cn=6L,cn=Barrel,cn=Crystal,cn=Product,cn=domain,
     * system/domain node PRESENT
     * trailing comma
    */
    public void setDN(String dn)
    {
        // strip off root path components
        String root = "cn="+getRoot()+",";
        if (dn.endsWith(mLocalPath))
        	dn = dn.substring(0, dn.lastIndexOf(mLocalPath));

        if (dn.endsWith(root))
        	dn = dn.substring(0, dn.lastIndexOf(root));

        ArrayList<String> newPath = new ArrayList<String>();
        StringTokenizer tok = new StringTokenizer(dn, ",");
        while (tok.hasMoreTokens()) {
            String nextPath = tok.nextToken();
            if (nextPath.indexOf("cn=") == 0)
                newPath.add(0, nextPath.substring(3));
            else
                break;
        }
        mPath = (newPath.toArray(mPath));
        mSysKey = INVALID;
        mStringPath = null;
        mDN = dn+root;
    }

    /*************************************************************************/

    /*
     * Getter Methods
     */

     // root is defined as 'domain', 'entity' or 'system' in subclasses
    public abstract String getRoot();

    public String[] getPath()
    {
        return mPath;
    }

    public String getString()
    {
        if (mStringPath == null) {
                StringBuffer stringPathBuffer = new StringBuffer("/").append(getRoot());
                for (String element : mPath)
					stringPathBuffer.append(delim).append(element);
                mStringPath = stringPathBuffer.toString();
        }
        return mStringPath;
    }

    public String getDN() {
        if (mDN == null) {
            StringBuffer dnBuffer = new StringBuffer();
            for (int i=mPath.length-1; i>=0; i--)
                dnBuffer.append("cn=").append(mPath[i]).append(",");
            dnBuffer.append("cn="+getRoot()+",");
            mDN = dnBuffer.toString();
        }
        return mDN;
    }

    public String getFullDN() {
        return getDN()+mLocalPath;
    }

    public boolean exists() {
        return Gateway.getLDAPLookup().exists(this);
    }

    /** Queries the lookup for the IOR
     */

    public org.omg.CORBA.Object getIOR() {
        org.omg.CORBA.Object newIOR = null;
        if (mIOR==null) { // if not cached try to resolve
            LDAPLookup myLookup = Gateway.getLDAPLookup();
            try {
                newIOR = myLookup.getIOR(this);
            } catch (ObjectNotFoundException ex) {
            }
            setIOR(newIOR);
        }
        return mIOR;
    }

    @Override
	public String toString() {
        return getString();
    }

    public short getType() {
        return mType;
    }

    public int getSysKey() {
        return mSysKey;
    }

    public Enumeration<? extends Path> getChildren() {
        String filter = "objectclass=*";
        LDAPSearchConstraints searchCons = new LDAPSearchConstraints();
        searchCons.setBatchSize(10);
        searchCons.setDereference(LDAPSearchConstraints.DEREF_FINDING );
        return Gateway.getLDAPLookup().search(getFullDN(), LDAPConnection.SCOPE_ONE,filter,searchCons);
    }

    public Path find(String name) throws ObjectNotFoundException {
    	Enumeration<Path> e = Gateway.getLDAPLookup().search(this, name);
    	if (e.hasMoreElements()) {
    		Path thisPath = e.nextElement();
    		if (e.hasMoreElements())
    			throw new ObjectNotFoundException("More than one match for "+name, "");
    		return thisPath;
    	}
    	throw new ObjectNotFoundException("No match for "+name, "");
    }

    public abstract EntityPath getEntity() throws ObjectNotFoundException;

    public abstract LDAPAttributeSet createAttributeSet() throws ObjectCannotBeUpdated;

    @Override
	public boolean equals( Object path )
    {
        return toString().equals(path.toString());
    }

    @Override
	public int hashCode() {
        return toString().hashCode();
    }

    public String dump() {
        StringBuffer comp = new StringBuffer("Components: { ");
        for (String element : mPath)
			comp.append("'").append(element).append("' ");
        return "Path - dump(): "+comp.toString()+"}\n        dn="+getDN()+"\n        string="+toString()+"\n        int="+getSysKey()+"\n        type="+mType;
    }
}