package org.kuali.maven.mojo.s3;
   
   import java.io.ByteArrayInputStream;
   import java.io.IOException;
   import java.io.InputStream;
   import java.text.SimpleDateFormat;
   import java.util.Collection;
   import java.util.Date;
   import java.util.List;
  import java.util.Map;
  import java.util.TimeZone;
  
  import org.apache.commons.beanutils.BeanUtils;
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.lang.StringUtils;
  import org.apache.maven.plugin.MojoExecutionException;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugin.descriptor.PluginDescriptor;
  import org.kuali.maven.common.UrlBuilder;
  
  import com.amazonaws.auth.AWSCredentials;
  import com.amazonaws.services.s3.AmazonS3Client;
  import com.amazonaws.services.s3.model.CannedAccessControlList;
  import com.amazonaws.services.s3.model.CopyObjectRequest;
  import com.amazonaws.services.s3.model.ListObjectsRequest;
  import com.amazonaws.services.s3.model.ObjectListing;
  import com.amazonaws.services.s3.model.ObjectMetadata;
  import com.amazonaws.services.s3.model.PutObjectRequest;
  import com.amazonaws.services.s3.model.S3Object;
  import com.amazonaws.services.s3.model.S3ObjectSummary;
  
  /**
   * <p>
   * This mojo updates a bucket serving as an origin for a Cloud Front distribution. It generates an html directory
   * listing for each "directory" in the bucket and stores the html under a key in the bucket such that a regular http
   * request for a directory returns the html instead of the XML for "object does not exist" Amazon would normally return.
   * For example: The url "http://www.mybucket.com/foo/bar" returns an html page containing a listing of all the files and
   * directories under "foo/bar" in the bucket.
   * </p>
   * <p>
   * If a directory contains an object with a key that is the same as the default object, the plugin copies the object to
   * a key representing the directory structure. For example, the url "http://www.mybucket.com/foo/bar/index.html"
   * represents an object in an S3 bucket under the key "foo/bar/index.html". This plugin will copy the object from the
   * key "foo/bar/index.html" to the key "foo/bar/". This causes the url "http://www.mybucket.com/foo/bar/" to return the
   * same content as the url "http://www.mybucket.com/foo/bar/index.html"
   * </p>
   * <p>
   * It also generates an html directory listing at the root of the bucket hierarchy and places that html into the bucket
   * as the default object, unless a default object already exists.
   * </p>
   *
   * @goal updateoriginbucket
   * @aggregator
   */
  public class UpdateOriginBucketMojo extends S3Mojo {
  
      private static final String S3_INDEX_METADATA_KEY = "maven-cloudfront-plugin-index";
      private static final String S3_INDEX_CONTENT_TYPE = "text/html";
      CloudFrontHtmlGenerator generator;
      S3DataConverter converter;
  
      /**
       * The groupId for the organization
       *
       * @parameter expression="${organizationGroupId}" default-value="org.kuali"
       */
      private String organizationGroupId;
  
      /**
       * This controls the caching behavior for CloudFront. By default, CloudFront edge locations cache content from an S3
       * bucket for 24 hours. That interval is shortened to 1 hour for the html indexes generated by this plugin.
       *
       * @parameter expression="${cacheControl}" default-value="max-age=3600, must-revalidate"
       */
      private String cacheControl;
  
      /**
       * If true, the complete hierarchy underneath <code>prefix</code> will be recursively updated. If false, only the
       * directory corresponding to the prefix will be updated along with the path back to the root of the bucket
       *
       * @parameter expression="${recurse}" default-value="true"
       */
      private boolean recurse;
  
      /**
       * If true, "foo/bar/index.html" will get copied to "foo/bar/"
       *
       * @parameter expression="${copyDefaultObjectWithDelimiter}" default-value="true"
       */
      private boolean copyDefaultObjectWithDelimiter;
  
      /**
       * If true, "foo/bar/index.html" will get copied to "foo/bar". This is defaulted to false because the relative
       * pathing in the html generated by the maven-site-plugin does not render correctly from a url without the trailing
       * slash.
       *
       * @parameter expression="${copyDefaultObjectWithoutDelimiter}" default-value="false"
       */
      private boolean copyDefaultObjectWithoutDelimiter;
 
     /**
      * The stylesheet to use for the directory listing
      *
      * @parameter expression="${css}" default-value="http://s3browse.ks.kuali.org/css/style.css"
      */
     private String css;
 
     /**
      * Image representing a file
      *
      * @parameter expression="${fileImage}" default-value="http://s3browse.ks.kuali.org/images/page_white.png"
      */
     private String fileImage;
 
     /**
      * Image representing a directory
      *
      * @parameter expression="${directoryImage}" default-value="http://s3browse.ks.kuali.org/images/folder.png"
      */
     private String directoryImage;
 
     /**
      * When displaying the last modified timestamp, use this timezone
      *
      * @parameter expression="${timezone}" default-value="GMT"
      */
     private String timezone;
 
     /**
      * When displaying the last modified timestamp use this format
      *
      * @parameter expression="${dateFormat}" default-value="EEE, dd MMM yyyy HH:mm:ss z"
      */
     private String dateFormat;
 
     /**
      * The key containing the default object for the Cloud Front distribution. If this object already exists, the plugin
      * will not modify it. If it does not exist, this plugin will generate an html directory listing and place it into
      * the bucket under this key.
      *
      * @parameter expression="${defaultObject}" default-value="index.html";
      */
     private String defaultObject;
 
     /**
      * The html for browsing a directory will be created under this key
      *
      * @parameter expression="${browseHtml}" default-value="browse.html";
      */
     private String browseHtml;
 
     @Override
     public void executeMojo() throws MojoExecutionException, MojoFailureException {
         try {
             getLog().info("Updating S3 bucket - " + getBucket());
             S3BucketContext context = getS3BucketContext();
             generator = new CloudFrontHtmlGenerator(context);
             converter = new S3DataConverter(context);
             converter.setBrowseHtml(getBrowseHtml());
             if (isRecurse()) {
                 getLog().info("Recursing into " + getPrefix());
                 recurse(context, getPrefix());
             }
             getLog().info("Updating hierarchy underneath " + getPrefix());
             goUpTheChain(context, getPrefix());
         } catch (Exception e) {
             throw new MojoExecutionException("Unexpected error: ", e);
         }
     }
 
     protected void goUpTheChain(final S3BucketContext context, final String startingPrefix) throws IOException {
         handleRoot(getS3PrefixContext(context, null));
 
         if (StringUtils.isEmpty(startingPrefix)) {
             return;
         }
 
         String[] prefixes = StringUtils.splitByWholeSeparator(startingPrefix, context.getDelimiter());
         if (prefixes.length == 1) {
             return;
         }
         String newPrefix = "";
         for (int i = 0; i < prefixes.length - 2; i++) {
             newPrefix += prefixes[i] + context.getDelimiter();
             updateDirectory(getS3PrefixContext(context, newPrefix));
         }
     }
 
     protected void updatePrefix() {
         UrlBuilder builder = new UrlBuilder();
         String sitePath = builder.getSitePath(getProject(), getOrganizationGroupId());
         String s = getPrefix();
         if (StringUtils.isEmpty(s)) {
             s = sitePath + "/" + getProject().getVersion() + "/";
         }
         if (!s.endsWith(getDelimiter())) {
             s = s + getDelimiter();
         }
         setPrefix(s);
     }
 
     protected S3BucketContext getS3BucketContext() throws MojoExecutionException {
         updateCredentials();
         validateCredentials();
         AWSCredentials credentials = getCredentials();
         AmazonS3Client client = new AmazonS3Client(credentials);
         updatePrefix();
         S3BucketContext context = new S3BucketContext();
         try {
             BeanUtils.copyProperties(context, this);
         } catch (Exception e) {
             throw new MojoExecutionException("Error copying properties", e);
         }
         context.setClient(client);
         context.setLastModifiedDateFormatter(getLastModifiedDateFormatter());
         context.setAbout(getAbout());
         return context;
     }
 
     /**
      * Create a PutObjectRequest for some html generated by this mojo. The PutObjectRequest sets the content type to
      * S3_INDEX_CONTENT_TYPE, sets the ACL to PublicRead, and adds some custom metadata so we can positively identify it
      * as an object created by this plugin
      */
     protected PutObjectRequest getPutIndexObjectRequest(final String html, final String key) throws IOException {
         InputStream in = new ByteArrayInputStream(html.getBytes());
         ObjectMetadata om = new ObjectMetadata();
         om.setCacheControl(getCacheControl());
         String contentType = S3_INDEX_CONTENT_TYPE;
         om.setContentType(contentType);
         om.setContentLength(html.length());
         om.addUserMetadata(S3_INDEX_METADATA_KEY, "true");
         PutObjectRequest request = new PutObjectRequest(getBucket(), key, in, om);
         request.setCannedAcl(CannedAccessControlList.PublicRead);
         return request;
     }
 
     /**
      * Return a SimpleDateFormat object initialized with the date format and timezone supplied to the mojo
      */
     protected SimpleDateFormat getLastModifiedDateFormatter() {
         SimpleDateFormat sdf = new SimpleDateFormat(getDateFormat());
         sdf.setTimeZone(TimeZone.getTimeZone(getTimezone()));
         return sdf;
     }
 
     /**
      * Return true if the Collection is null or contains no entries, false otherwise
      */
     protected boolean isEmpty(final Collection<?> c) {
         return c == null || c.size() == 0;
     }
 
     /**
      * Show some text about this plugin
      */
     protected String getAbout() {
         String date = getLastModifiedDateFormatter().format(new Date());
         PluginDescriptor descriptor = (PluginDescriptor) this.getPluginContext().get("pluginDescriptor");
         if (descriptor == null) {
             // Maven 2.2.1 is returning a null descriptor
             return "Listing generated by the maven-cloudfront-plugin on " + date;
         } else {
             String name = descriptor.getArtifactId();
             String version = descriptor.getVersion();
             return "Listing generated by the " + name + " v" + version + " on " + date;
         }
     }
 
     /**
      * Create an object in the bucket under a key that lets a normal http request function correctly with CloudFront /
      * S3.<br>
      * Either use the client's object or upload some html created by this plugin<br>
      */
     protected void updateDirectory(final S3PrefixContext context, final boolean isCopyIfExists, final String copyToKey)
             throws IOException {
         S3BucketContext bucketContext = context.getBucketContext();
         AmazonS3Client client = context.getBucketContext().getClient();
         String bucket = bucketContext.getBucket();
 
         boolean containsDefaultObject = isExistingObject(context.getObjectListing(), context.getDefaultObjectKey());
         if (containsDefaultObject && isCopyIfExists) {
             // Copy the contents of the clients default object
             String sourceKey = context.getDefaultObjectKey();
             String destKey = copyToKey;
             CopyObjectRequest request = getCopyObjectRequest(bucket, sourceKey, destKey);
             getLog().info("Copy: " + sourceKey + " to " + destKey);
             client.copyObject(request);
         } else {
             // Upload our custom content
             PutObjectRequest request = getPutIndexObjectRequest(context.getHtml(), copyToKey);
             getLog().info("Put: " + copyToKey);
             client.putObject(request);
         }
     }
 
     /**
      * Update this S3 "directory".
      */
     protected void updateDirectory(final S3PrefixContext context) throws IOException {
         String trimmedPrefix = converter.getTrimmedPrefix(context.getPrefix(), context.getBucketContext()
                 .getDelimiter());
 
         // Handle "http://www.mybucket.com/foo/bar/"
         updateDirectory(context, isCopyDefaultObjectWithDelimiter(), context.getPrefix());
 
         // Handle "http://www.mybucket.com/foo/bar"
         updateDirectory(context, isCopyDefaultObjectWithoutDelimiter(), trimmedPrefix);
 
         // Handle "http://www.mybucket.com/foo/bar/browse.html"
         // context.getBucketContext().getClient().putObject(getPutIndexObjectRequest(context.getHtml(),
         // context.getBrowseHtmlKey()));
     }
 
     /**
      * If this is the root of the bucket and the default object either does not exist or was created by this plugin,
      * overwrite the default object with newly generated html. Otherwise, do nothing.
      */
     protected void handleRoot(final S3PrefixContext context) throws IOException {
         if (!context.isRoot()) {
             return;
         }
 
         AmazonS3Client client = context.getBucketContext().getClient();
 
         // Handle "http://www.mybucket.com/browse.html"
         PutObjectRequest request1 = getPutIndexObjectRequest(context.getHtml(), context.getBrowseHtmlKey());
         getLog().info("Put: " + context.getBrowseHtmlKey());
         client.putObject(request1);
 
         boolean isCreateOrUpdateDefaultObject = isCreateOrUpdateDefaultObject(context);
         if (!isCreateOrUpdateDefaultObject) {
             return;
         }
 
         // Update the default object
         PutObjectRequest request2 = getPutIndexObjectRequest(context.getHtml(), context.getDefaultObjectKey());
         getLog().info("Put: " + context.getDefaultObjectKey());
         client.putObject(request2);
     }
 
     protected S3PrefixContext getS3PrefixContext(final S3BucketContext context, final String prefix) {
         ListObjectsRequest request = new ListObjectsRequest(context.getBucket(), prefix, null, context.getDelimiter(),
                 1000);
         ObjectListing objectListing = context.getClient().listObjects(request);
         List<String[]> data = converter.getData(objectListing, prefix, context.getDelimiter());
         String html = generator.getHtml(data, prefix, context.getDelimiter());
         String defaultObjectKey = StringUtils.isEmpty(prefix) ? getDefaultObject() : prefix + getDefaultObject();
         String browseHtmlKey = StringUtils.isEmpty(prefix) ? getBrowseHtml() : prefix + getBrowseHtml();
         // Is this the root of the bucket?
         boolean isRoot = StringUtils.isEmpty(prefix);
 
         S3PrefixContext prefixContext = new S3PrefixContext();
         prefixContext.setObjectListing(objectListing);
         prefixContext.setHtml(html);
         prefixContext.setRoot(isRoot);
         prefixContext.setDefaultObjectKey(defaultObjectKey);
         prefixContext.setPrefix(prefix);
         prefixContext.setBucketContext(context);
         prefixContext.setBrowseHtmlKey(browseHtmlKey);
         return prefixContext;
     }
 
     /**
      * Recurse the hierarchy of a bucket starting at "prefix" and create entries in the bucket corresponding to the
      * directory structure of the hierarchy
      */
     protected void recurse(final S3BucketContext context, final String prefix) throws IOException {
         S3PrefixContext prefixContext = getS3PrefixContext(context, prefix);
 
         handleRoot(prefixContext);
 
         // If this is not the root, there is more to do
         if (!prefixContext.isRoot()) {
             updateDirectory(prefixContext);
         }
 
         // Recurse down the hierarchy
         List<String> commonPrefixes = prefixContext.getObjectListing().getCommonPrefixes();
         for (String commonPrefix : commonPrefixes) {
             recurse(context, commonPrefix);
         }
     }
 
     /**
      * Return true if the ObjectListing contains an object under "key"
      */
     protected boolean isExistingObject(final ObjectListing objectListing, final String key) {
         List<S3ObjectSummary> summaries = objectListing.getObjectSummaries();
         for (S3ObjectSummary summary : summaries) {
             if (key.equals(summary.getKey())) {
                 return true;
             }
         }
         return false;
     }
 
     /**
      * Return true if there is no object in the ObjectListing under defaultObjectKey.<br>
      * Return true if the object in the ObjectListing was created by this plugin.<br>
      * Return false otherwise.<br>
      */
     protected boolean isCreateOrUpdateDefaultObject(final S3PrefixContext context) {
         if (!isExistingObject(context.getObjectListing(), context.getDefaultObjectKey())) {
             // There is no default object, we are free to create one
             return true;
         }
         S3BucketContext s3Context = context.getBucketContext();
         // There is a default object, but if it was created by this plugin, we
         // still need to update it
         S3Object s3Object = s3Context.getClient().getObject(s3Context.getBucket(), context.getDefaultObjectKey());
         boolean isOurDefaultObject = isOurObject(s3Object);
         IOUtils.closeQuietly(s3Object.getObjectContent());
         if (isOurDefaultObject) {
             return true;
         } else {
             return false;
         }
     }
 
     /**
      * Return true if this S3Object was created by this plugin. This is is done by checking the metadata attached to
      * this object for the presence of a custom value.
      */
     protected boolean isOurObject(final S3Object s3Object) {
         ObjectMetadata metadata = s3Object.getObjectMetadata();
         Map<String, String> userMetadata = metadata.getUserMetadata();
         String value = userMetadata.get(S3_INDEX_METADATA_KEY);
         boolean isOurObject = "true".equals(value);
         return isOurObject;
     }
 
     /**
      * Create a CopyObjectRequest with an ACL set to PublicRead
      */
     protected CopyObjectRequest getCopyObjectRequest(final String bucket, final String sourceKey, final String destKey) {
         CopyObjectRequest request = new CopyObjectRequest(bucket, sourceKey, bucket, destKey);
         request.setCannedAccessControlList(CannedAccessControlList.PublicRead);
         return request;
     }
 
     public String getTimezone() {
         return timezone;
     }
 
     public void setTimezone(final String timezone) {
         this.timezone = timezone;
     }
 
     public String getDateFormat() {
         return dateFormat;
     }
 
     public void setDateFormat(final String dateFormat) {
         this.dateFormat = dateFormat;
     }
 
     public String getDefaultObject() {
         return defaultObject;
     }
 
     public void setDefaultObject(final String defaultCloudFrontObject) {
         this.defaultObject = defaultCloudFrontObject;
     }
 
     public String getFileImage() {
         return fileImage;
     }
 
     public void setFileImage(final String fileImage) {
         this.fileImage = fileImage;
     }
 
     public String getDirectoryImage() {
         return directoryImage;
     }
 
     public void setDirectoryImage(final String directoryImage) {
         this.directoryImage = directoryImage;
     }
 
     public String getCss() {
         return css;
     }
 
     public void setCss(final String css) {
         this.css = css;
     }
 
     public boolean isCopyDefaultObjectWithDelimiter() {
         return copyDefaultObjectWithDelimiter;
     }
 
     public void setCopyDefaultObjectWithDelimiter(final boolean copyDefaultObjectWithDelimiter) {
         this.copyDefaultObjectWithDelimiter = copyDefaultObjectWithDelimiter;
     }
 
     public boolean isCopyDefaultObjectWithoutDelimiter() {
         return copyDefaultObjectWithoutDelimiter;
     }
 
     public void setCopyDefaultObjectWithoutDelimiter(final boolean copyDefaultObjectWithoutDelimiter) {
         this.copyDefaultObjectWithoutDelimiter = copyDefaultObjectWithoutDelimiter;
     }
 
     public String getCacheControl() {
         return cacheControl;
     }
 
     public void setCacheControl(final String cacheControl) {
         this.cacheControl = cacheControl;
     }
 
     public String getBrowseHtml() {
         return browseHtml;
     }
 
     public void setBrowseHtml(final String browseHtml) {
         this.browseHtml = browseHtml;
     }
 
     /**
      * @return the recurse
      */
     public boolean isRecurse() {
         return recurse;
     }
 
     /**
      * @param recurse
      * the recurse to set
      */
     public void setRecurse(final boolean recurse) {
         this.recurse = recurse;
     }
 
     /**
      * @return the organizationGroupId
      */
     public String getOrganizationGroupId() {
         return organizationGroupId;
     }
 
     /**
      * @param organizationGroupId
      * the organizationGroupId to set
      */
     public void setOrganizationGroupId(final String organizationGroupId) {
         this.organizationGroupId = organizationGroupId;
     }
 
 }