/**
 * This work was created by participants in the DataONE project, and is
 * jointly copyrighted by participating institutions in DataONE. For 
 * more information on DataONE, see our web site at http://dataone.org.
 *
 *   Copyright ${year}
 *
 * 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.
 * 
 * $Id$
 */

package org.dataone.mimemultipart;

import java.io.*;
import java.util.*;


import javax.servlet.http.HttpServletRequest;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUpload;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.log4j.Logger;

/*
 * Copyright 2002-2010 the original author or authors.
 *
 * 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.
 */
/**
 * DataOne conversion of HttpServletRequests into a DataONE MultipartRequest via
 *  <a href="http://jakarta.apache.org/commons/fileupload">Jakarta Commons FileUpload</a>
 * 1.2 or above. Inspired by <a href="http://static.springsource.org/spring/docs/3.0.x/javadoc-api/org/springframework/web/multipart/MultipartResolver.html">MultipartResolver</a>
 * but almost entirely rewritten by DataONE.
 *
 * <p>Provides "maxUploadSize", "maxMemorySize" and "tmpUploadDir" settings as
 * bean properties. See corresponding
 * ServletFileUpload / DiskFileItemFactory properties ("sizeMax", "sizeThreshold",
 * ) for details in terms of defaults and accepted values.
 *
 * <p>Saves temporary files to the temporary directory.
 *
 * @author Robert P. Waltz (DataONE)
 * @author Trevor D. Cook (Original)
 * @author Juergen Hoeller (Original)
 * @since 29.09.2003
 * @see #CommonsMultipartResolver(ServletContext)
 * @see org.springframework.web.portlet.multipart.CommonsPortletMultipartResolver
 * @see org.apache.commons.fileupload.servlet.ServletFileUpload
 * @see org.apache.commons.fileupload.disk.DiskFileItemFactory
 */
public class MultipartRequestResolver {

    Logger logger = Logger.getLogger(MultipartRequestResolver.class.getName());
    private DiskFileItemFactory factory;
    private org.apache.commons.fileupload.servlet.ServletFileUpload upload;
    final static int SIZE = 16384;

    /**
     * constructor.  
     * @param filePartFile a Directory path to write any file contents to.
     *
     */
    public MultipartRequestResolver() {
        // Create a factory for disk-based file items
        this.factory = new DiskFileItemFactory();

        // Create a new file upload handler
        this.upload = new ServletFileUpload(this.factory);

    }

    public MultipartRequestResolver(String tmpUploadDir) {
        this.factory = new DiskFileItemFactory();
        this.factory.setRepository(new File(tmpUploadDir));
        this.upload = new ServletFileUpload(factory);
    }

    public MultipartRequestResolver(String tmpUploadDir, int maxUploadSize) {
        this.factory = new DiskFileItemFactory();

        // Set factory constraints
        this.factory.setRepository(new File(tmpUploadDir));

        // Create a new file upload handler
        this.upload = new ServletFileUpload(factory);

        // Set overall request size constraint
        this.upload.setSizeMax(maxUploadSize);

    }

    public MultipartRequestResolver(String tmpUploadDir, int maxUploadSize, int maxMemorySize) {
        this.factory = new DiskFileItemFactory();

        // Set factory constraints
        this.factory.setSizeThreshold(maxMemorySize);
        this.factory.setRepository(new File(tmpUploadDir));

        // Create a new file upload handler
        this.upload = new ServletFileUpload(factory);

        // Set overall request size constraint
        this.upload.setSizeMax(maxUploadSize);

    }

    /**
     * get the parts of a
     *
     * @throws IOException 
     */
    public MultipartRequest resolveMultipart(HttpServletRequest request) throws IOException, FileUploadException, Exception {
        Map<String, List<String>> mpParams = new HashMap<String, List<String>>();
        Map<String, File> mpFiles = new HashMap<String, File>();
        MultipartRequest multipartRequest = new MultipartRequest(request, mpFiles, mpParams);
        if (!isMultipartContent(request)) {
            return multipartRequest;
        }
        List<?> /*FileItem */ items = upload.parseRequest(request);
        Iterator<?> iter = items.iterator();
        while (iter.hasNext()) {
            FileItem item = (FileItem) iter.next();

            if (item.isFormField()) {
                String name = item.getFieldName();
                String value = item.getString();
                if (mpParams.containsKey(name)) {
                    mpParams.get(name).add(value);
                } else {
                    List<String> values = new ArrayList<String>();
                    values.add(value);
                    mpParams.put(name, values);
                }
            } else {
                // processUploadedFile(item);

                if (item instanceof DiskFileItem) {
                    DiskFileItem diskItem = (DiskFileItem) item;

                    String fileKey = diskItem.getFieldName();

                    if (diskItem.isInMemory()) {
                        File fileItem = diskItem.getStoreLocation();
//                        File fileItem = new File(this.factory.getRepository().getAbsolutePath() + fileKey);
                        if (fileItem.exists()) {
                            logger.info("length: " + Long.toString(fileItem.length()) + " lastModified: " + Long.toString(fileItem.lastModified()) + " is it really a file: " + fileItem.isFile());
                        } else {
                            logger.debug("force creation of  " + fileItem.getAbsolutePath());
                            fileItem.createNewFile();
                            fileItem.deleteOnExit();
                            fileItem.setWritable(true);
                            fileItem.setReadable(true);
//                            FileOutputStream fileItemOutput = new FileOutputStream(fileItem);
                            diskItem.write(fileItem);
                            
                        }

                        mpFiles.put(fileKey, fileItem);
                    } else {
                        mpFiles.put(fileKey, diskItem.getStoreLocation());
                    }
                } else {
                    throw new FileUploadException("unable to determine file location of Multipart Form named: " + item.getName());
                }
            }
        }
        return multipartRequest;
    }

    public static final boolean isMultipartContent(HttpServletRequest request) 
    {
        if ("post".equals(request.getMethod().toLowerCase()) || 
            "put".equals(request.getMethod().toLowerCase())) {
        	
            String contentType = request.getContentType();
            if (contentType == null) {
                return false;
            }
            if (contentType.toLowerCase().startsWith(FileUpload.MULTIPART)) {
                return true;
            }
        }
        return false;

    }
}