package org.kuali.maven.mojo.s3;
   
   import java.text.NumberFormat;
   import java.util.ArrayList;
   import java.util.Collections;
   import java.util.Comparator;
   import java.util.List;
   
   import org.apache.commons.lang.StringUtils;
  
  import com.amazonaws.services.s3.model.ObjectListing;
  import com.amazonaws.services.s3.model.S3ObjectSummary;
  
  /**
   * Convert information from an S3 bucket into pojo's
   */
  public class S3DataConverter {
      HtmlUtils html = new HtmlUtils();
      NumberFormat nf = getNumberFormatInstance();
      S3BucketContext context;
      String browseKey;
  
      public S3DataConverter() {
          this(null);
      }
  
      public S3DataConverter(final S3BucketContext context) {
          super();
          this.context = context;
      }
  
      /**
       * Return a NumberFormat that does not using grouping and always displays one fraction digit. This is used to
       * display the size of S3 objects in kilobytes
       */
      protected NumberFormat getNumberFormatInstance() {
          NumberFormat nf = NumberFormat.getInstance();
          nf.setMaximumFractionDigits(1);
          nf.setMinimumFractionDigits(1);
          nf.setGroupingUsed(false);
          return nf;
      }
  
      /**
       * Convert "foo/bar/css/" into "foo/bar/css"<br>
       * Convert "foo/bar/css" into "foo/bar"<br>
       */
      protected String getTrimmedPrefix(final String prefix, final String delimiter) {
          int pos = prefix.lastIndexOf(delimiter);
          if (pos == -1) {
              return prefix;
          }
          return prefix.substring(0, pos);
      }
  
      /**
       * Convert each DisplayRow object in the list to a String[] and add the String[] to the list of data
       */
      protected void addDisplayRows(final List<DisplayRow> displayRows, final List<String[]> data) {
          for (DisplayRow displayRow : displayRows) {
              addDisplayRow(displayRow, data);
          }
      }
  
      /**
       * Convert a DisplayRow object to a String[]
       */
      protected void addDisplayRow(final DisplayRow displayRow, final List<String[]> data) {
          if (displayRow == null) {
              return;
          }
          String[] row = new String[4];
          row[0] = displayRow.getImage();
          row[1] = displayRow.getAhref();
          row[2] = displayRow.getLastModified();
          row[3] = displayRow.getSize();
          data.add(row);
      }
  
      /**
       * Trim the prefix off of the text we display for this object.<br>
       * Display "style.css" instead of "css/style.css"
       */
      protected String getShow(final String key, final String prefix) {
          if (prefix == null) {
              return key;
          }
          int index = prefix.length();
          String s = key.substring(index);
          return s;
      }
  
      /**
       * Convert a commonPrefix into a DisplayRow object for the UI
       */
      protected DisplayRow getDisplayRow(final String commonPrefix, final String prefix, final String delimiter) {
  
          // Create some UI friendly strings
          String image = html.getImage(context.getDirectoryImage());
         String show = getShow(commonPrefix, prefix);
         String dest = delimiter + commonPrefix;
         String ahref = html.getHref(dest, show);
         String date = "-";
         String size = "-";
 
         // Store them in an object
         DisplayRow displayRow = new DisplayRow();
         displayRow.setImage(image);
         displayRow.setAhref(ahref);
         displayRow.setLastModified(date);
         displayRow.setSize(size);
         displayRow.setShow(show);
         return displayRow;
     }
 
     protected List<DisplayRow> getDirectoryDisplayRows(final ObjectListing objectListing, final String prefix,
             final String delimiter) {
         List<DisplayRow> displayRows = new ArrayList<DisplayRow>();
         for (String commonPrefix : objectListing.getCommonPrefixes()) {
             DisplayRow displayRow = getDisplayRow(commonPrefix, prefix, delimiter);
             if (displayRow == null) {
                 continue;
             }
             displayRows.add(displayRow);
         }
         return displayRows;
     }
 
     /**
      * Convert the ObjectListing into a List of String arrays. Each array in the list represents one row in the html
      * table we will be generating
      */
     public List<String[]> getData(final ObjectListing objectListing, final String prefix, final String delimiter) {
         DisplayRow upOneDirectory = getUpOneDirectoryDisplayRow(prefix, delimiter);
         List<DisplayRow> objectDisplayRows = getObjectDisplayRows(objectListing, prefix, delimiter);
         List<DisplayRow> directoryDisplayRows = getDirectoryDisplayRows(objectListing, prefix, delimiter);
         Comparator<DisplayRow> c = new DisplayRowComparator();
         Collections.sort(directoryDisplayRows, c);
         List<String[]> data = new ArrayList<String[]>();
         addDisplayRow(upOneDirectory, data);
         addDisplayRows(directoryDisplayRows, data);
         addDisplayRows(objectDisplayRows, data);
         return data;
     }
 
     protected boolean isDirectory(S3ObjectSummary summary, List<String> commonPrefixes, String prefix, String delimiter) {
         String key = summary.getKey();
         if (key.equals(prefix)) {
             return true;
         }
         for (String commonPrefix : commonPrefixes) {
             if (key.equals(commonPrefix)) {
                 return true;
             }
             String trimmedPrefix = getTrimmedPrefix(commonPrefix, delimiter);
             if (key.equals(trimmedPrefix)) {
                 return true;
             }
         }
         return false;
     }
 
     /**
      * Convert an S3ObjectSummary into a DisplayRow object for the UI
      */
     protected DisplayRow getDisplayRow(final S3ObjectSummary summary, final String prefix, final String delimiter) {
         String key = summary.getKey();
 
         // Create some UI friendly strings
         String image = html.getImage(context.getFileImage());
         String show = getShow(key, prefix);
         String dest = delimiter + key;
         String ahref = html.getHref(dest, show);
         String date = context.getLastModifiedDateFormatter().format(summary.getLastModified());
         String size = nf.format((summary.getSize() / 1024D)) + " KiB";
 
         // Store them in an object
         DisplayRow displayRow = new DisplayRow();
         displayRow.setShow(show);
         displayRow.setImage(image);
         displayRow.setAhref(ahref);
         displayRow.setLastModified(date);
         displayRow.setSize(size);
         return displayRow;
     }
 
     protected List<DisplayRow> getObjectDisplayRows(final ObjectListing objectListing, final String prefix,
             final String delimiter) {
         List<DisplayRow> displayRows = new ArrayList<DisplayRow>();
         for (S3ObjectSummary summary : objectListing.getObjectSummaries()) {
             if (isDirectory(summary, objectListing.getCommonPrefixes(), prefix, delimiter)) {
                 continue;
             }
             DisplayRow displayRow = getDisplayRow(summary, prefix, delimiter);
             if (displayRow == null) {
                 continue;
             }
             displayRows.add(displayRow);
         }
         return displayRows;
     }
 
     /**
      * Convert a commonPrefix into a DisplayRow object for the UI
      */
     protected DisplayRow getUpOneDirectoryDisplayRow(final String prefix, final String delimiter) {
         if (StringUtils.isEmpty(prefix)) {
             return null;
         }
 
         // Create some UI friendly strings
         String image = "";
         String show = ".." + delimiter;
         String dest = getUpOneDirectoryDest(prefix, delimiter);
         String ahref = html.getHref(dest, show);
         String date = "";
         String size = "";
 
         // Store them in an object
         DisplayRow displayRow = new DisplayRow();
         displayRow.setImage(image);
         displayRow.setAhref(ahref);
         displayRow.setLastModified(date);
         displayRow.setSize(size);
         return displayRow;
     }
 
     /**
      * If prefix is "foo/" and delimiter is "/" return "/"<br>
      * If prefix is "foo/bar/" and delimiter is "/" return "foo/"
      */
     protected String getUpOneDirectoryDest(String prefix, final String delimiter) {
         if (prefix.endsWith(delimiter)) {
             prefix = prefix.substring(0, prefix.length() - 1);
         }
         int pos = prefix.lastIndexOf(delimiter);
         if (pos == -1) {
             return delimiter + getBrowseKey();
         } else {
             return delimiter + prefix.substring(0, pos + 1);
         }
     }
 
     public void setContext(final S3BucketContext context) {
         this.context = context;
     }
 
     public S3BucketContext getContext() {
         return context;
     }
 
     public String getBrowseKey() {
         return browseKey;
     }
 
     public void setBrowseKey(final String browseHtml) {
         this.browseKey = browseHtml;
     }
 
 }