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 browseHtml;
  
  	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(final S3ObjectSummary summary, final List<String> commonPrefixes,
 			final String prefix, final 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 + getBrowseHtml();
 		} else {
 			return delimiter + prefix.substring(0, pos + 1);
 		}
 	}
 
 	public void setContext(final S3BucketContext context) {
 		this.context = context;
 	}
 
 	public S3BucketContext getContext() {
 		return context;
 	}
 
 	public String getBrowseHtml() {
 		return browseHtml;
 	}
 
 	public void setBrowseHtml(final String browseHtml) {
 		this.browseHtml = browseHtml;
 	}
 
 }