/*******************************************************************************
 * Copyright (c) 2008, 2011 VMware Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *   VMware Inc. - initial contribution
 *******************************************************************************/
package org.eclipse.virgo.management.console;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.management.ManagementFactory;
import java.net.URI;
import java.util.ArrayList;
import java.util.List;

import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectName;
import javax.management.openmbean.CompositeDataSupport;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.osgi.framework.BundleContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * 
 *
 */
public class UploadServlet extends HttpServlet {

	private static final String[] DEPLOYMENT_IDENTITY_FIELDS = new String[]{"type", "symbolicName", "version"};

	private static final int HTTP_RESPONSE_INTERNAL_SERVER_ERROR = 500;

    private static final String ORG_ECLIPSE_VIRGO_KERNEL_HOME = "org.eclipse.virgo.kernel.home";
    
    private static final String DEPLOYER_MBEAN_NAME = "org.eclipse.virgo.kernel:category=Control,type=Deployer";
	
	private static final long serialVersionUID = 1L;
	
	private static final String STAGING_DIR = "/work/org.eclipse.virgo.apps.admin.web.UploadServlet";
	
	private static final Logger log = LoggerFactory.getLogger(UploadServlet.class);

	private MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
	
	private String serverHome = null;
	
	private BundleContext bundleContext = null;

	public UploadServlet() {
	}
	
	public UploadServlet(BundleContext bundleContext) {
		this.bundleContext = bundleContext;
	}

	/**
	 * Do not use this method with the HTTPService unless the BundleContext has already been set.
	 */
    public void init(ServletConfig config) throws ServletException {
    	super.init(config);
    	if(bundleContext == null){
    		this.bundleContext = (BundleContext) config.getServletContext().getAttribute("osgi-bundlecontext");
    	}
		this.serverHome = this.bundleContext.getProperty(ORG_ECLIPSE_VIRGO_KERNEL_HOME);
    }
	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException {
		try {
		    File stagingDir = createStagingDirectory();
			FileItemFactory factory = new DiskFileItemFactory();
			ServletFileUpload upload = new ServletFileUpload(factory);
		    response.setContentType("text/html");
			List<FileItem> items = (List<FileItem>) upload.parseRequest(request);
			List<File> uploadedFiles = new ArrayList<File>();
			for (FileItem fileItem : items) {
				File uploadedFile = this.doUpload(fileItem, stagingDir);
				if(uploadedFile != null){
					uploadedFiles.add(uploadedFile);
				}
			}
			doDeployment(uploadedFiles, response);
		} catch (IllegalArgumentException ea){
		    PrintWriter writer = response.getWriter();
	        writer.append("<ol id=\"uploadResults\"><li>File name contains '/' or '\\', this is not allowed.</ol>");
			writer.close();
		} catch (Exception e) {
		    log.error(e.toString());
			response.sendError(HTTP_RESPONSE_INTERNAL_SERVER_ERROR, e.toString());
		}
	}
	
	File doUpload(FileItem fileItem, File stagingDir) throws Exception{
		if (!fileItem.isFormField()) {
			String name = fileItem.getName();
			if(name != null && name.length() > 0){
				if(name.contains("\\") || name.contains("/")){
					throw new IllegalArgumentException("Security violation, file name contains '/' or '\\'");
				}
				File uploadedFile = new File(stagingDir, name);
				fileItem.write(uploadedFile);
				log.info(String.format("Uploaded artifact of size (%db) to %s", fileItem.getSize(), uploadedFile.getPath()));
				return uploadedFile;
			}
		}
		return null;
	}
	
	private void doDeployment(List<File> uploadedFiles, HttpServletResponse response) throws MalformedObjectNameException, NullPointerException, IOException{
		ObjectName objectName = new ObjectName(DEPLOYER_MBEAN_NAME);
	    PrintWriter writer = response.getWriter();
        writer.append("<ol id=\"uploadResults\">");
        for (File file : uploadedFiles) {
			URI uri = file.toURI();
			try {
				Object invoke = this.mBeanServer.invoke(objectName, "deploy", new Object[]{uri.toString()}, new String[]{String.class.getName()});
				writer.append("<li>" + file.getName() + " deployed as " + getDeploymentIdentity(invoke) + "</li>");
			} catch (Exception e) {
				writer.append("<li>" + file.getName() + " failed to deploy '" + e.getMessage() + "'</li>");
			}
			writer.append("<li />");
		}
        writer.append("</ol>");
		writer.close();
	}
	
	private String getDeploymentIdentity(Object deploymentIdentity) {
		StringBuilder builder = new StringBuilder();
		if(deploymentIdentity instanceof CompositeDataSupport){
			CompositeDataSupport deploymentIdentityInstance = (CompositeDataSupport) deploymentIdentity;
			Object[] all = deploymentIdentityInstance.getAll(DEPLOYMENT_IDENTITY_FIELDS);
			builder.append(all[0]);
			builder.append(" - ").append(all[1]);
			builder.append(": ").append(all[2]);
		}
		return builder.toString();
	}

    private File createStagingDirectory() throws IOException {
        File pathReference = new File(String.format("%s%s", this.serverHome, STAGING_DIR));
        if (!pathReference.exists()) {
        	if (!pathReference.mkdirs()) {
        		throw new IOException("Unable to create directory " + pathReference.getAbsolutePath());
        	}
        }
        return pathReference.getAbsoluteFile();
    }

}