/*
 * $Header: /home/cvs/jakarta-commons/httpclient/src/java/org/apache/commons/httpclient/methods/MultipartPostMethod.java,v 1.17.2.4 2004/06/13 20:24:49 olegk Exp $
 * $Revision: 1.17.2.4 $
 * $Date: 2004/06/13 20:24:49 $
 *
 * ====================================================================
 *
 *  Copyright 2002-2004 The Apache Software Foundation
 *
 *  Licensed 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * .
 *
 * [Additional notices, if required by prior licensing conditions]
 *
 */

package org.apache.commons.httpclient.methods;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;

import org.apache.commons.httpclient.HttpConnection;
import org.apache.commons.httpclient.HttpException;
import org.apache.commons.httpclient.HttpState;
import org.apache.commons.httpclient.methods.multipart.FilePart;
import org.apache.commons.httpclient.methods.multipart.Part;
import org.apache.commons.httpclient.methods.multipart.StringPart;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Implements the HTTP multipart POST method.
 * 

 * The HTTP multipart POST method is defined in section 3.3 of
 * RFC1867:
 * 

 * The media-type multipart/form-data follows the rules of all multipart
 * MIME data streams as outlined in RFC 1521. The multipart/form-data contains 
 * a series of parts. Each part is expected to contain a content-disposition 
 * header where the value is "form-data" and a name attribute specifies 
 * the field name within the form, e.g., 'content-disposition: form-data; 
 * name="xxxxx"', where xxxxx is the field name corresponding to that field.
 * Field names originally in non-ASCII character sets may be encoded using 
 * the method outlined in RFC 1522.
 * 
 * 

 * 

 *
 * @author Matthew Albright
 * @author Jeff Dever
 * @author Adrian Sutton
 * @author Mark Diggory
 * @author Mike Bowler
 * @author Oleg Kalnichevski
 *
 * @since 2.0
 */
public class MultipartPostMethod extends ExpectContinueMethod {

    /** The Content-Type for multipart/form-data. */
    public static final String MULTIPART_FORM_CONTENT_TYPE = 
        "multipart/form-data";

    /** Log object for this class. */
    private static final Log LOG = LogFactory.getLog(MultipartPostMethod.class);

    /** The parameters for this method */
    private final List parameters = new ArrayList();

    /**
     * No-arg constructor.
     */
    public MultipartPostMethod() {
        super();
    }

    /**
     * Constructor specifying a URI.
     *
     * @param uri either an absolute or relative URI
     */
    public MultipartPostMethod(String uri) {
        super(uri);
    }

    /**
     * Constructor specifying a URI and tempDir.
     *
     * @param uri either an absolute or relative URI
     * @param tempDir directory to store temp files in
     */
    public MultipartPostMethod(String uri, String tempDir) {
        super(uri, tempDir);
    }

    /**
     * Constructor specifying a URI, tempDir and tempFile.
     *
     * @param uri either an absolute or relative URI
     * @param tempDir directory to store temp files in
     * @param tempFile file to store temporary data in
     */
    public MultipartPostMethod(String uri, String tempDir, String tempFile) {
        super(uri, tempDir, tempFile);
    }

    /**
     * Returns true 
     * 
     * @return true
     * 
     * @since 2.0beta1
     */
    protected boolean hasRequestContent() {
        return true;
    }

    /**
     * Returns "POST".
     * @return "POST"
     */
    public String getName() {
        return "POST";
    }

    /**
     * Adds a text field part
     * 
     * @param parameterName The name of the parameter.
     * @param parameterValue The value of the parameter.
     */
    public void addParameter(String parameterName, String parameterValue) {
        LOG.trace("enter addParameter(String parameterName, String parameterValue)");
        Part param = new StringPart(parameterName, parameterValue);
        parameters.add(param);
    }

    /**
     * Adds a binary file part
     * 
     * @param parameterName The name of the parameter
     * @param parameterFile The name of the file.
     * @throws FileNotFoundException If the file cannot be found.
     */
    public void addParameter(String parameterName, File parameterFile) 
    throws FileNotFoundException {
        LOG.trace("enter MultipartPostMethod.addParameter(String parameterName, "
            + "File parameterFile)");
        Part param = new FilePart(parameterName, parameterFile);
        parameters.add(param);
    }

    /**
     * Adds a binary file part with the given file name
     * 
     * @param parameterName The name of the parameter
     * @param fileName The file name
     * @param parameterFile The file
     * @throws FileNotFoundException If the file cannot be found.
     */
    public void addParameter(String parameterName, String fileName, File parameterFile) 
    throws FileNotFoundException {
        LOG.trace("enter MultipartPostMethod.addParameter(String parameterName, "
            + "String fileName, File parameterFile)");
        Part param = new FilePart(parameterName, fileName, parameterFile);
        parameters.add(param);
    }
        
    /**
     * Adds a part.
     * 
     * @param part The part to add.
     */
    public void addPart (final Part part) {
        LOG.trace("enter addPart(Part part)");
        parameters.add(part);
    }

    /**
     * Returns all parts.
     * 
     * @return an array of containing all parts
     */
    public Part[] getParts() {
        return (Part[]) parameters.toArray(new Part[parameters.size()]);
    }
    /**
     * Adds Content Type: multipart/form-data header in addition 
     * to the "standard" set of headers
     * 
     * @param state the {@link HttpState state} information associated with this method
     * @param conn the {@link HttpConnection connection} used to execute
     *        this HTTP method
     *
     * @throws IOException if an I/O (transport) error occurs
     * @throws HttpException  if a protocol exception occurs.
     * @throws HttpRecoverableException if a recoverable transport error occurs. 
     *                    Usually this kind of exceptions can be recovered from by
     *                    retrying the HTTP method 
     */
    protected void addRequestHeaders(HttpState state, HttpConnection conn) 
    throws IOException, HttpException {
        LOG.trace("enter MultipartPostMethod.addRequestHeaders(HttpState state, "
            + "HttpConnection conn)");
        super.addRequestHeaders(state, conn);
        
        if (!parameters.isEmpty()) {
            StringBuffer buffer = new StringBuffer(MULTIPART_FORM_CONTENT_TYPE);
            if (Part.getBoundary() != null) {
                buffer.append("; boundary=");
                buffer.append(Part.getBoundary());
            }
            setRequestHeader("Content-Type", buffer.toString());
        }
    }

    /**
     * Writes the request body to the given {@link HttpConnection connection}.
     *
     * @param state the {@link HttpState state} information associated with this method
     * @param conn the {@link HttpConnection connection} used to execute
     *        this HTTP method
     *
     * @return true
     *
     * @throws IOException if an I/O (transport) error occurs
     * @throws HttpException  if a protocol exception occurs.
     * @throws HttpRecoverableException if a recoverable transport error occurs. 
     *                    Usually this kind of exceptions can be recovered from by
     *                    retrying the HTTP method 
     */
    protected boolean writeRequestBody(HttpState state, HttpConnection conn) 
    throws IOException, HttpException {
        LOG.trace("enter MultipartPostMethod.writeRequestBody(HttpState state, "
            + "HttpConnection conn)");
        OutputStream out = conn.getRequestOutputStream();
        Part.sendParts(out, getParts());
        return true;
    }

    /**
     * 
Return the length of the request body.
     *
     * 
Once this method has been invoked, the request parameters cannot be
     * altered until the method is {@link #recycle recycled}.
     * 
     * @return The request content length.
     */
    protected int getRequestContentLength() {
        LOG.trace("enter MultipartPostMethod.getRequestContentLength()");
        try {
            long len = Part.getLengthOfParts(getParts());
            // Chop the length to the max int value.
            if (len <= Integer.MAX_VALUE) {
                return (int) len;
            } else {
                return (Integer.MAX_VALUE);
            }
        } catch (IOException e) {
            // Can't throw an IOException and still override
            throw new RuntimeException(e.toString());
        }
    }


    /**
     * Recycles the HTTP method so that it can be used again.
     * Note that all of the instance variables will be reset
     * once this method has been called. This method will also
     * release the connection being used by this HTTP method.
     * 
     * @see #releaseConnection()
     * 
     * @deprecated no longer supported and will be removed in the future
     *             version of HttpClient
     */
    public void recycle() {
        LOG.trace("enter MultipartPostMethod.recycle()");
        super.recycle();
        parameters.clear();
    }
}