import java.util.*;

import java.io.IOException;

import com.allaire.cfx.*;

import org.apache.lucene.analysis.*;

import org.apache.lucene.document.*;

import org.apache.lucene.index.*;

import org.apache.lucene.queryParser.*;

import org.apache.lucene.search.*;





/**

 * @author Aaron Johnson: ajohnson@cephas.net

 * Description: This CFX tag will, given a keyword(s) and

 * a starting/ending point, search a Lucene full text index

 * and return a query object to for ColdFusion to loop 

 * over and display the results.

 * 

 * Usage: <cfx_lucene 

 * 			query="r_query"

 * 			indexName="c:\hosts\mysite.com\myindex"

 * 			startIndex="5" 

 * 			maxPage="20"

 * 			queryString="foo">

 */

public class lucene implements CustomTag {



	// for debugging

	public static void main(String args[]) {

		

		int startindex = 0; //the first index displayed on this page

        int maxpage    = 50; //the maximum items displayed on this page

        String queryString = null; //the query entered in the previous page

		String indexName = "c:\\hosts\\mysite.com\\myindex";

		

		// gather values from the command line if necessary

		if(args.length == 0) {	

			System.err.println("Useage: java lucene <search term>");

			return;

		} else {

			queryString = args[0];

		}



		// Do a test of the search

		Hits hits;

		try {

			hits = doSearch(indexName,startindex,maxpage,queryString);



			System.out.println("Found " + hits.length() + " results");

			Document doc;



			for(int i=0;i<hits.length();i++) {

				// get the document and contents

				doc = hits.doc(i);                    

				String doctitle = doc.get("title");

				String url = doc.get("url");

				String docSummary = doc.get("summary");



				// print out

				System.out.println(i + " - " + doctitle + "(" + url + ")");

				System.out.println("\t" + docSummary);

			}

		} catch(Exception e) {

			System.err.println("Error - " + e);

		}

	}

	

	

	// implement the processRequest() method of the CustomTag interface

	public void processRequest(Request req, Response res) {

		

		/* attributes: 

		 * startIndex: integer, the first index displayed on this page

		 * maxPage: integer, the maximum items displayed on this page

		 * queryString: string, the query entered on the page

		 * indexName: string, the path to the lucene index

		 * query: string, the name of the query to be returned to the calling template

		*/ 

		

		Vector errors = new Vector();

		

		String indexName = req.getAttribute("indexName"); 

        int startIndex = req.getIntAttribute("startIndex");

        int maxPage    = req.getIntAttribute("maxPage");

        String queryString = req.getAttribute("queryString");

		String query = req.getAttribute("query");



        Hits hits = null;

        int thispage = 0;

		

		// do attribute validation

		if (!req.attributeExists("indexName")) {

			errors.add("The cfx_lucene tag requires an attribute called 'indexName'.");

		}

			

		if (!req.attributeExists("startIndex")) {

			startIndex = 1;

		}

		

		if (!req.attributeExists("maxPage")) {

			maxPage = 500;

		}	

		

		if (!req.attributeExists("queryString")) {

			errors.add("The cfx_lucene tag requires an attribute called 'queryString'.");

		}





		if (errors.isEmpty()) {

			try {

				hits = doSearch(indexName,startIndex,maxPage,queryString);

			} catch (Exception e) {

				//any error that happens is probably due to a permission

				// problem or non-existant or otherwise corrupt index

				errors.add("The search index you specified could not be found. More information:<br />" + e.toString());

			}	

		} else {

			errors.add("Skipping doing the search owing to a previous error");

		}



		

		// Always add the query to the page, otherwise coldfusion

		// will barf about our query variable not existing



		// Define column indexes

		String[] columns = { "URL", "TITLE", "SUMMARY" } ;

		int iUrl = 1, iTitle = 2, iSummary = 3 ;



		// Create a query which contains these columns

		com.allaire.cfx.Query q = res.addQuery(query, columns) ;





		// do the query....

		if (errors.isEmpty() && hits != null) {  

			thispage = maxPage;



           	// only return up to the max the user requested

       		if ((startIndex + maxPage) > hits.length()) {

        		thispage = hits.length() - startIndex;

			}



        	// loop over all the results, add each to the query

   	    	for (int i = startIndex; i < (thispage + startIndex); i++) { 

				Document doc = null;

				try {

					// get the next document 

	       			doc = hits.doc(i);                    

				} catch (IOException ie) {

					errors.add("Error fetching document for result " + i + ", " + ie);

				}



				// Data entries

				String doctitle = null;

				String url = null;

				String docSummary = null;



				if(doc != null) {

					doctitle = doc.get("title"); // get its title if we can

					url = doc.get("url");

					docSummary = doc.get("summary");

				

					// use url if document title doesn't exist

					if ((doctitle == null) || doctitle.equals("")) { //use the url if it has no title

						doctitle = url;

					}

				}

						

				// add the data to the query

				int iRow = q.addRow() ;

				q.setData( iRow, iUrl, url) ;

				q.setData( iRow, iTitle, doctitle);

				q.setData( iRow, iSummary, docSummary); 

       		}

		} else {

			errors.add("No results found due to a previous error");

        }

        

        

        // everything should be done now... if we have errors, write 

		// those out to the calling template

        if (!errors.isEmpty()) {

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

        		res.write("<p>Error:" + errors.get(i) + "</p>\n");

        	}

        }

	}





	// Actually do the search

	private static Hits doSearch(String indexName, int startIndex, int maxPage, String queryString) throws Exception {

        IndexSearcher searcher = null; 

        // absolute named because because Query is also an object

        // in the com.allaire.cfx package

        org.apache.lucene.search.Query luceneQuery = null; 

        Hits hits = null;

        int thispage = 0;             

		



		// Make a new searcher

       	searcher = new IndexSearcher(IndexReader.open(indexName) );

		if(searcher == null) { throw new Exception("Unable to open index"); }

		



		// Build up the query

       	Analyzer analyzer = new StopAnalyzer();

		luceneQuery = QueryParser.parse(queryString, "contents", analyzer); //parse the 

		if(luceneQuery == null) { throw new Exception("Unable to build Query"); }





		// Do the search

		hits = searcher.search(luceneQuery);

	



		// Return the search

		return hits;

	}

}