/*

 * Copyright (c) 1995, 2006, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.net.www;

import java.net.URL;

import java.net.ContentHandler;

import java.util.*;

import java.io.InputStream;

import java.io.OutputStream;

import java.io.BufferedInputStream;

import java.net.UnknownServiceException;

/**

 * A class to represent an active connection to an object

 * represented by a URL.

 * @author  James Gosling

 */

abstract public class URLConnection extends java.net.URLConnection {

    /** The URL that it is connected to */

    private String contentType;

    private int contentLength = -1;

    protected MessageHeader properties;

    /** Create a URLConnection object.  These should not be created directly:

        instead they should be created by protocol handers in response to

        URL.openConnection.

        @param  u       The URL that this connects to.

     */

    public URLConnection (URL u) {

        super(u);

        properties = new MessageHeader();

    }

    /** Call this routine to get the property list for this object.

     * Properties (like content-type) that have explicit getXX() methods

     * associated with them should be accessed using those methods.  */

    public MessageHeader getProperties() {

        return properties;

    }

    /** Call this routine to set the property list for this object. */

    public void setProperties(MessageHeader properties) {

        this.properties = properties;

    }

    public void setRequestProperty(String key, String value) {

        if(connected)

            throw new IllegalAccessError("Already connected");

        if (key == null)

            throw new NullPointerException ("key cannot be null");

        properties.set(key, value);

    }

    /**

     * The following three methods addRequestProperty, getRequestProperty,

     * and getRequestProperties were copied from the superclass implementation

     * before it was changed by CR:6230836, to maintain backward compatibility.

     */

    public void addRequestProperty(String key, String value) {

        if (connected)

            throw new IllegalStateException("Already connected");

        if (key == null)

            throw new NullPointerException ("key is null");

    }

    public String getRequestProperty(String key) {

        if (connected)

            throw new IllegalStateException("Already connected");

        return null;

    }

    public Map<String,List<String>> getRequestProperties() {

        if (connected)

            throw new IllegalStateException("Already connected");

        return Collections.EMPTY_MAP;

    }

    public String getHeaderField(String name) {

        try {

            getInputStream();

        } catch (Exception e) {

            return null;

        }

        return properties == null ? null : properties.findValue(name);

    }

    /**

     * Return the key for the nth header field. Returns null if

     * there are fewer than n fields.  This can be used to iterate

     * through all the headers in the message.

     */

    public String getHeaderFieldKey(int n) {

        try {

            getInputStream();

        } catch (Exception e) {

            return null;

        }

        MessageHeader props = properties;

        return props == null ? null : props.getKey(n);

    }

    /**

     * Return the value for the nth header field. Returns null if

     * there are fewer than n fields.  This can be used in conjunction

     * with getHeaderFieldKey to iterate through all the headers in the message.

     */

    public String getHeaderField(int n) {

        try {

            getInputStream();

        } catch (Exception e) {

            return null;

        }

        MessageHeader props = properties;

        return props == null ? null : props.getValue(n);

    }

    /** Call this routine to get the content-type associated with this

     * object.

     */

    public String getContentType() {

        if (contentType == null)

            contentType = getHeaderField("content-type");

        if (contentType == null) {

            String ct = null;

            try {

                ct = guessContentTypeFromStream(getInputStream());

            } catch(java.io.IOException e) {

            }

            String ce = properties.findValue("content-encoding");

            if (ct == null) {

                ct = properties.findValue("content-type");

                if (ct == null)

                    if (url.getFile().endsWith("/"))

                        ct = "text/html";

                    else

                        ct = guessContentTypeFromName(url.getFile());

            }

            /*

             * If the Mime header had a Content-encoding field and its value

             * was not one of the values that essentially indicate no

             * encoding, we force the content type to be unknown. This will

             * cause a save dialog to be presented to the user.  It is not

             * ideal but is better than what we were previously doing, namely

             * bringing up an image tool for compressed tar files.

             */

            if (ct == null || ce != null &&

                    !(ce.equalsIgnoreCase("7bit")

                      || ce.equalsIgnoreCase("8bit")

                      || ce.equalsIgnoreCase("binary")))

                ct = "content/unknown";

            setContentType(ct);

        }

        return contentType;

    }

    /**

     * Set the content type of this URL to a specific value.

     * @param   type    The content type to use.  One of the

     *                  content_* static variables in this

     *                  class should be used.

     *                  eg. setType(URL.content_html);

     */

    public void setContentType(String type) {

        contentType = type;

        properties.set("content-type", type);

    }

    /** Call this routine to get the content-length associated with this

     * object.

     */

    public int getContentLength() {

        try {

            getInputStream();

        } catch (Exception e) {

            return -1;

        }

        int l = contentLength;

        if (l < 0) {

            try {

                l = Integer.parseInt(properties.findValue("content-length"));

                setContentLength(l);

            } catch(Exception e) {

            }

        }

        return l;

    }

    /** Call this routine to set the content-length associated with this

     * object.

     */

    protected void setContentLength(int length) {

        contentLength = length;

        properties.set("content-length", String.valueOf(length));

    }

    /**

     * Returns true if the data associated with this URL can be cached.

     */

    public boolean canCache() {

        return url.getFile().indexOf('?') < 0   /* && url.postData == null

                REMIND */ ;

    }

    /**

     * Call this to close the connection and flush any remaining data.

     * Overriders must remember to call super.close()

     */

    public void close() {

        url = null;

    }

}