/*
 * 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 javax.mail.internet;

// http://www.faqs.org/rfcs/rfc2183.html

/**
 * @version $Rev$ $Date$
 */
public class ContentDisposition {
    private String _disposition;
    private ParameterList _list;

    public ContentDisposition() {
        setDisposition(null);
        setParameterList(null);
    }

    public ContentDisposition(String disposition) throws ParseException {
        // get a token parser for the type information
        HeaderTokenizer tokenizer = new HeaderTokenizer(disposition, HeaderTokenizer.MIME);

        // get the first token, which must be an ATOM
        HeaderTokenizer.Token token = tokenizer.next();
        if (token.getType() != HeaderTokenizer.Token.ATOM) {
            throw new ParseException("Invalid content disposition");
        }

        _disposition = token.getValue();

        // the remainder is parameters, which ParameterList will take care of parsing.
        String remainder = tokenizer.getRemainder();
        if (remainder != null) {
            _list = new ParameterList(remainder);
        }
    }

    public ContentDisposition(String disposition, ParameterList list) {
        setDisposition(disposition);
        setParameterList(list);
    }

    public String getDisposition() {
        return _disposition;
    }

    public String getParameter(String name) {
        if (_list == null) {
            return null;
        } else {
            return _list.get(name);
        }
    }

    public ParameterList getParameterList() {
        return _list;
    }

    public void setDisposition(String string) {
        _disposition = string;
    }

    public void setParameter(String name, String value) {
        if (_list == null) {
            _list = new ParameterList();
        }
        _list.set(name, value);
    }

    public void setParameterList(ParameterList list) {
        if (list == null) {
            _list = new ParameterList();
        } else {
            _list = list;
        }
    }

    public String toString() {
        // it is possible we might have a parameter list, but this is meaningless if
        // there is no disposition string.  Return a failure.
        if (_disposition == null) {
            return null;
        }


        // no parameter list?  Just return the disposition string
        if (_list == null) {
            return _disposition;
        }

        // format this for use on a Content-Disposition header, which means we need to
        // account for the length of the header part too.
        return _disposition + _list.toString("Content-Disposition".length() + _disposition.length());
    }
}