/*

 * Copyright (c) 2008, Harald Kuhr

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *     * Redistributions of source code must retain the above copyright

 *       notice, this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above copyright

 *       notice, this list of conditions and the following disclaimer in the

 *       documentation and/or other materials provided with the distribution.

 *     * Neither the name "TwelveMonkeys" nor the

 *       names of its contributors may be used to endorse or promote products

 *       derived from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */



package com.twelvemonkeys.servlet.fileupload;



import org.apache.commons.fileupload.*;

import org.apache.commons.fileupload.servlet.ServletRequestContext;

import org.apache.commons.fileupload.disk.DiskFileItemFactory;



import javax.servlet.http.HttpServletRequestWrapper;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.ServletException;

import java.io.File;

import java.util.*;



/**

 * An {@code HttpFileUploadRequest} implementation, based on

 * <a href="http://jakarta.apache.org/commons/fileupload/">Jakarta Commons FileUpload</a>.

 *

 * @author <a href="mailto:harald.kuhr@gmail.com">Harald Kuhr</a>

 * @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-servlet/src/main/java/com/twelvemonkeys/servlet/fileupload/HttpFileUploadRequestWrapper.java#1 $

 */

class HttpFileUploadRequestWrapper extends HttpServletRequestWrapper implements HttpFileUploadRequest {



    private final Map<String, String[]> parameters = new HashMap<String, String[]>();

    private final Map<String, UploadedFile[]> files = new HashMap<String, UploadedFile[]>();



    public HttpFileUploadRequestWrapper(HttpServletRequest pRequest, File pUploadDir, long pMaxSize) throws ServletException {

        super(pRequest);



        DiskFileItemFactory factory = new DiskFileItemFactory(

                128 * 1024, // 128 KByte

                new File(pUploadDir.getAbsolutePath())

        );

        FileUpload upload = new FileUpload(factory);

        upload.setSizeMax(pMaxSize);



        // TODO: Defer request parsing??

        try {

            //noinspection unchecked

            List<FileItem> items = upload.parseRequest(new ServletRequestContext(pRequest));

            for (FileItem item : items) {

                if (item.isFormField()) {

                    processFormField(item.getFieldName(), item.getString());

                }

                else {

                    processeFile(item);

                }

            }

        }

        catch (FileUploadBase.SizeLimitExceededException e) {

            throw new FileSizeExceededException(e);

        }

        catch (org.apache.commons.fileupload.FileUploadException e) {

            throw new FileUploadException(e);

        }

    }



    private void processeFile(final FileItem pItem) {

        UploadedFile value = new UploadedFileImpl(pItem);

        String name = pItem.getFieldName();



        UploadedFile[] values;

        UploadedFile[] oldValues = files.get(name);



        if (oldValues != null) {

            values = new UploadedFile[oldValues.length + 1];

            System.arraycopy(oldValues, 0, values, 0, oldValues.length);

            values[oldValues.length] = value;

        }

        else {

            values = new UploadedFile[] {value};

        }



        files.put(name, values);



        // Also add to normal fields

        processFormField(name, value.getName());

    }



    private void processFormField(String pName, String pValue) {

        // Multiple parameter values are not that common, so it's

        // probably faster to just use arrays...

        // TODO: Research and document...

        String[] values;

        String[] oldValues = parameters.get(pName);



        if (oldValues != null) {

            values = new String[oldValues.length + 1];

            System.arraycopy(oldValues, 0, values, 0, oldValues.length);

            values[oldValues.length] = pValue;

        }

        else {

            values = new String[] {pValue};

        }



        parameters.put(pName, values);

    }



    public Map getParameterMap() {

        // TODO: The spec dicates immutable map, but what about the value arrays?!

        // Probably just leave as-is, for performance

        return Collections.unmodifiableMap(parameters);

    }



    public Enumeration getParameterNames() {

        return Collections.enumeration(parameters.keySet());

    }



    public String getParameter(String pString) {

        String[] values = getParameterValues(pString);

        return values != null ? values[0] : null;

    }



    public String[] getParameterValues(String pString) {

        // TODO: Optimize?

        return parameters.get(pString).clone();

    }



    public UploadedFile getUploadedFile(String pName) {

        UploadedFile[] files = getUploadedFiles(pName);

        return files != null ? files[0] : null;

    }



    public UploadedFile[] getUploadedFiles(String pName) {

        // TODO: Optimize?

        return files.get(pName).clone();

    }

}