/*
 *  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.
 */

/**
 * @author Alexander Y. Kleymenov
 */

package org.apache.harmony.security.x509;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;

import org.apache.harmony.security.asn1.ASN1SequenceOf;
import org.apache.harmony.security.asn1.ASN1Type;
import org.apache.harmony.security.asn1.BerInputStream;

/**
 * The class encapsulates the ASN.1 DER encoding/decoding work with the
 * GeneralNames structure which is a part of X.509 certificate (as specified in
 * RFC 3280 - Internet X.509 Public Key Infrastructure. Certificate and
 * Certificate Revocation List (CRL) Profile.
 * http://www.ietf.org/rfc/rfc3280.txt):
 * 
 * 
 * <pre>
 *   GeneralNames ::= SEQUENCE SIZE (1..MAX) OF GeneralName
 * </pre>
 * 
 * @see org.apache.harmony.security.x509.NameConstraints
 * @see org.apache.harmony.security.x509.GeneralSubtree
 */
public class GeneralNames {

	// the values of GeneralName
	private List<GeneralName> generalNames;
	// the ASN.1 encoded form of GeneralNames
	private byte[] encoding;

	/**
	 * ASN.1 DER X.509 GeneralNames encoder/decoder class.
	 */
	public static final ASN1Type ASN1 = new ASN1SequenceOf(GeneralName.ASN1) {

		@Override
		public Object getDecodedObject(BerInputStream in) {
			return new GeneralNames((List<GeneralName>) in.content,
					in.getEncoded());
		}

		@Override
		public Collection<GeneralName> getValues(Object object) {
			final GeneralNames gns = (GeneralNames) object;
			return gns.generalNames;
		}
	};

	/**
	 * Constructs an object representing the value of GeneralNames.
	 */
	public GeneralNames() {
		generalNames = new ArrayList<GeneralName>();
	}

	/**
	 * TODO
	 * 
	 * @param generalNames
	 *            : List
	 */
	public GeneralNames(List<GeneralName> generalNames) {
		this.generalNames = generalNames;
	}

	//
	// TODO
	// @param generalNames: List
	// @param encoding: byte[]
	//
	private GeneralNames(List<GeneralName> generalNames, byte[] encoding) {
		this.generalNames = generalNames;
		this.encoding = encoding;
	}

	/**
	 * TODO
	 * 
	 * @param name
	 *            : GeneralName
	 * @return
	 */
	public void addName(GeneralName name) {
		encoding = null;
		if (generalNames == null) {
			generalNames = new ArrayList<GeneralName>();
		}
		generalNames.add(name);
	}

	/**
	 * Places the string representation of extension value into the StringBuffer
	 * object.
	 */
	public void dumpValue(StringBuffer buffer, String prefix) {
		if (generalNames == null) {
			return;
		}
		for (final GeneralName generalName : generalNames) {
			buffer.append(prefix);
			buffer.append(generalName);
			buffer.append('\n');
		}
	}

	/* *
	 * TODO
	 * 
	 * @param name: GeneralName
	 * 
	 * @return
	 * 
	 * public GeneralName getNameByTag(int tag) { encoding = null; if
	 * ((generalNames == null) || (generalNames.size() == 0)) { return null; }
	 * for (int i=0; i<generalNames.size(); i++) { if (((GeneralName)
	 * generalName.get(i)).getTag() == tag) { } } generalNames.add(name); }
	 */

	/**
	 * Returns ASN.1 encoded form of this X.509 GeneralNames value.
	 * 
	 * @return a byte array containing ASN.1 encode form.
	 */
	public byte[] getEncoded() {
		if (encoding == null) {
			encoding = ASN1.encode(this);
		}
		return encoding;
	}

	/**
	 * Returns the list of values.
	 * 
	 * @return names
	 */
	public List<GeneralName> getNames() {
		if ((generalNames == null) || (generalNames.size() == 0)) {
			return null;
		}
		return new ArrayList<GeneralName>(generalNames);
	}

	/**
	 * Returns the collection of pairs: (Integer (tag), Object (name value))*
	 * 
	 * @return the collection of pairs: (Integer (tag), Object (name value))*
	 */
	public List<List<?>> getPairsList() {
		final ArrayList<List<?>> result = new ArrayList<List<?>>();
		if (generalNames == null) {
			return result;
		}
		final Iterator<GeneralName> it = generalNames.iterator();
		while (it.hasNext()) {
			result.add(it.next().getAsList());
		}
		return result;
	}
}