import org.apache.commons.digester.Digester;
import org.xml.sax.SAXException;

import org.apache.lucene.util.Version;
import java.util.ArrayList;
import java.util.List;

import java.io.File;
import java.io.IOException;
import java.io.FileNotFoundException;

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.Writer;

import java.io.OutputStreamWriter;
import java.io.FileOutputStream;


/**
	* Generates centroids given docs list in a XML file
	*
	*/
	public class CentroidGenerator
{

	List<Centroid> centroids;

	public List<Centroid> getCentroids() {

		for (int i=0; i<centroids.size(); i++) {
			centroids.get(i).averageTime();
			centroids.get(i).averageLat();
			centroids.get(i).averageLng();
		}

		return centroids;
	}

	public void nextItem(FlickrDoc flickrDoc)
	{

		if (centroids == null) {

			centroids = new ArrayList<Centroid>();

			Centroid centroid = new Centroid(flickrDoc.getTitle(), flickrDoc.getDescription(), flickrDoc.getTime(), flickrDoc.getTags(), flickrDoc.getEvent());

			if ( (flickrDoc.getLatitude() != null) && (flickrDoc.getLongitude() != null) ) {
				centroid.setLat(flickrDoc.getLatitude());
				centroid.setLng(flickrDoc.getLongitude());
			}

			centroids.add(centroid);

		} else {

			String existing;
			Boolean merged = false;
			for (int i=0; i<centroids.size(); i++) {

				if (flickrDoc.getEvent().equals(centroids.get(i).getEvent())) {

					existing = centroids.get(i).getTitle();
					centroids.get(i).appendTitle(flickrDoc.getTitle());

					existing = centroids.get(i).getDescription();
					centroids.get(i).appendDescription(flickrDoc.getDescription());

					existing = centroids.get(i).getTime();
					centroids.get(i).appendTime(flickrDoc.getTime());

					existing = centroids.get(i).getTags();
					centroids.get(i).appendTags(flickrDoc.getTags());

					if ( (flickrDoc.getLatitude() != null) && (flickrDoc.getLongitude() != null) ) {
						centroids.get(i).appendLat(flickrDoc.getLatitude());
						centroids.get(i).appendLng(flickrDoc.getLongitude());
					}

					merged = true;
					break;
				}
			}

			if (!merged) {
				Centroid centroid = new Centroid(flickrDoc.getTitle(), flickrDoc.getDescription(), flickrDoc.getTime(), flickrDoc.getTags(), flickrDoc.getEvent());

				if ( (flickrDoc.getLatitude() != null) && (flickrDoc.getLongitude() != null) ) {
					centroid.setLat(flickrDoc.getLatitude());
					centroid.setLng(flickrDoc.getLongitude());
				}

				centroids.add(centroid);
			}
		}

	}

	/**
		* Configures Digester rules and actions, parses the XML file specified
		* as the first argument.
		*
		* @param args command line arguments
		*/
		public static void main(String[] args) throws IOException, SAXException
	{

		System.out.println("Centroid Generator...");

		// instantiate Digester and disable XML validation
		Digester digester = new Digester();
		digester.setValidating(false);

		// instantiate CollectionIndexer class
		digester.addObjectCreate("collection", CentroidGenerator.class );
		// instantiate Document class
		digester.addObjectCreate("collection/doc", FlickrDoc.class );

		// set type property of Document instance when 'type' attribute is found
		//digester.addSetProperties("collection/doc",         "type", "type" );

		// set different properties of Document instance using specified methods
		digester.addCallMethod("collection/doc/id",       "setId", 0);
		digester.addCallMethod("collection/doc/title",    "setTitle", 0);
		digester.addCallMethod("collection/doc/description",       "setDescription", 0);
		digester.addCallMethod("collection/doc/time",   "setTime", 0);
		digester.addCallMethod("collection/doc/tags", "setTags", 0);
		digester.addCallMethod("collection/doc/geo/latitude",    "setLatitude", 0);
		digester.addCallMethod("collection/doc/geo/longitude",    "setLongitude", 0);
		digester.addCallMethod("collection/doc/event",  "setEvent", 0);

		// call 'addDocument' method when the next 'collection/document' pattern is seen
		digester.addSetNext("collection/doc", "nextItem" );

		// now that rules and actions are configured, start the parsing process
		CentroidGenerator abp = (CentroidGenerator) digester.parse(new File(args[0]));

		StringBuffer contents = new StringBuffer();
		contents.append("<?xml version='1.0' encoding='utf-8'?>" + System.getProperty("line.separator"));
		contents.append("<collection>").append(System.getProperty("line.separator"));


		List<Centroid> cent = abp.getCentroids();

		for (int i=0; i<cent.size(); i++) {

			contents.append("<doc>" + System.getProperty("line.separator"));

			contents.append("<id>");
			contents.append(i);
			contents.append("</id>" + System.getProperty("line.separator"));

			contents.append("<title>");
			contents.append(cent.get(i).getTitle());
			contents.append("</title>" + System.getProperty("line.separator"));

			contents.append("<description>");
			contents.append(cent.get(i).getDescription());
			contents.append("</description>" + System.getProperty("line.separator"));

			contents.append("<time>");
			contents.append(cent.get(i).getTime());
			contents.append("</time>" + System.getProperty("line.separator"));

			contents.append("<tags>");
			contents.append(cent.get(i).getTags());
			contents.append("</tags>" + System.getProperty("line.separator"));

			contents.append("<geo>" + System.getProperty("line.separator"));

			contents.append("<lat>");
			if (cent.get(i).getLat() != null) contents.append(cent.get(i).getLat());
			contents.append("</lat>" + System.getProperty("line.separator"));

			contents.append("<lng>");
			if (cent.get(i).getLng() != null) contents.append(cent.get(i).getLng());
			contents.append("</lng>" + System.getProperty("line.separator"));

			contents.append("</geo>" + System.getProperty("line.separator"));

			contents.append("<event>");
			contents.append(cent.get(i).getEvent());
			contents.append("</event>" + System.getProperty("line.separator"));

			contents.append("</doc>" + System.getProperty("line.separator"));
		}
		contents.append("</collection>" + System.getProperty("line.separator") + System.getProperty("line.separator"));


		Writer writer = null;

		try {
			//File fileOutput = new File("output.trectext");
			File fileOutput = new File(args[1]);
			writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileOutput), "UTF8"));
			writer.write(contents.toString());
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				if (writer != null) {
					writer.close();
				}
			} catch (IOException e) {
				e.printStackTrace();
			}
		}



	}

	/**
		* Flickr structured document.
		*
		*/
		public static class FlickrDoc
	{
		//private String type;
		private String id;
		private String title;
		private String description;
		private String time;
		private String tags;
		private String latitude;
		private String longitude;
		private String event;

		public void setId(String newId)
		{
			id = newId;
		}
		public String getId()
		{
			return id;
		}

		public void setTitle(String newTitle)
		{
			title = newTitle;
		}
		public String getTitle()
		{
			return title;
		}

		public void setDescription(String newDescription)
		{
			description = newDescription;
		}
		public String getDescription()
		{
			return description;
		}

		public void setTime(String newTime)
		{
			time = newTime;
		}
		public String getTime()
		{
			return time;
		}

		public void setTags(String newTags)
		{
			tags = newTags;
		}
		public String getTags()
		{
			return tags;
		}

		public void setLatitude(String newLatitude)
		{
			latitude = newLatitude;
		}
		public String getLatitude()
		{
			return latitude;
		}

		public void setLongitude(String newLongitude)
		{
			longitude = newLongitude;
		}
		public String getLongitude()
		{
			return longitude;
		}

		public void setEvent(String newEvent)
		{
			event = newEvent;
		}
		public String getEvent()
		{
			return event;
		}
	}

	public static class Centroid
	{
		private String title;
		private String description;
		private String time;
		private String tags;
		private String latitude;
		private String longitude;
		private String event;


		public Centroid(String newTitle, String newDescription, String newTime, String newTags, String newEvent) {
			title = newTitle;
			description = newDescription;
			tags = newTags;
			time = newTime;
			event = newEvent;
		}

		public void setTitle(String newTitle)
		{
			title = newTitle;
		}

		public void appendTitle(String newTitle)
		{
			title = title + " " + newTitle;
		}

		public String getTitle()
		{
			return title;
		}

		public void setDescription(String newDescription)
		{
			description = newDescription;
		}

		public void appendDescription(String newDescription)
		{
			description = description + " " + newDescription;
		}

		public String getDescription()
		{
			return description;
		}

		public void setTime(String newTime)
		{
			time = newTime;
		}

		public void appendTime(String newTime)
		{
			time = time + " " + newTime;
		}

		public void averageTime()
		{
			String[] timeValues = time.split(" ");
			int sum = 0;
			for (int i = 0; i < timeValues.length; i++) {
				sum = sum + Integer.parseInt(timeValues[i]);
			}
			time = Integer.toString(sum / timeValues.length);
		}

		public String getTime()
		{
			return time;
		}

		public void setTags(String newTags)
		{
			tags = newTags;
		}

		public void appendTags(String newTags)
		{
			tags = tags + " " + newTags;
		}

		public String getTags()
		{
			return tags;
		}

		public void setLat(String newLatitude)
		{
			latitude = newLatitude;
		}

		public void appendLat(String newLatitude)
		{
			latitude = latitude + " " + newLatitude;
		}

		public void averageLat()
		{
			if (latitude!=null) {
				if (!latitude.equals("null")) {
					String[] latValues = latitude.split(" ");
					float sum = 0;
					int counter = 0;
					for (int i = 0; i < latValues.length; i++) {
						if (!latValues[i].equals("null")) {
						sum = sum + Float.valueOf(latValues[i].trim()).floatValue();
						counter = counter +1;
					}
					}
					latitude = Float.toString(sum / (float) counter);

				}
			}
		}

		public String getLat()
		{
			return latitude;
		}

		public void setLng(String newLongitude)
		{
			longitude = newLongitude;
		}

		public void appendLng(String newLongitude)
		{
			longitude = longitude + " " + newLongitude;
		}

		public void averageLng()
		{
				if (longitude!=null) {
					if (!longitude.equals("null")) {
						String[] lngValues = longitude.split(" ");
						float sum = 0;
						int counter = 0;
						for (int i = 0; i < lngValues.length; i++) {
							if (!lngValues[i].equals("null")) {
							sum = sum + Float.valueOf(lngValues[i].trim()).floatValue();
							counter = counter +1;
						}
						}
						longitude = Float.toString(sum / (float) counter);
					}
				}
		}

		public String getLng()
		{
			return longitude;
		}

		public void setEvent(String newEvent)
		{
			event = newEvent;
		}

		public String getEvent()
		{
			return event;
		}
	}
}