package de.mpg.mpiwg.berlin.mpdl.servlets.cms;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Date;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.lucene.document.Fieldable;
import org.apache.lucene.search.Query;

import de.mpg.mpiwg.berlin.mpdl.cms.document.Document;
import de.mpg.mpiwg.berlin.mpdl.cms.document.DocumentHandler;
import de.mpg.mpiwg.berlin.mpdl.cms.document.Hits;
import de.mpg.mpiwg.berlin.mpdl.cms.lucene.IndexHandler;

public class QueryDocuments extends HttpServlet {
  private static final long serialVersionUID = 1L;
  public QueryDocuments() {
    super();
  }

  public void init(ServletConfig config) throws ServletException  {
    super.init(config);
  }

  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    request.setCharacterEncoding("utf-8");
    response.setCharacterEncoding("utf-8");
    String query = request.getParameter("query");
    String sortBy = request.getParameter("sortBy");
    String[] sortFields = null;
    if (sortBy != null && ! sortBy.trim().isEmpty())
      sortFields = sortBy.split(" ");
    String language = request.getParameter("language");  // optional: is also detected by translator service
    if (language != null && language.equals("none"))
      language = null;
    String translate = request.getParameter("translate");
    String pageStr = request.getParameter("page");
    if (pageStr == null)
      pageStr = "1";
    int page = Integer.parseInt(pageStr);
    String pageSizeStr = request.getParameter("pageSize");
    if (pageSizeStr == null)
      pageSizeStr = "10";
    int pageSize = Integer.parseInt(pageSizeStr);
    int from = (page * pageSize) - pageSize;  // e.g. 0
    int to = page * pageSize - 1;  // e.g. 9
    String outputFormat = request.getParameter("outputFormat");
    if (outputFormat == null)
      outputFormat = "html";
    if (outputFormat.equals("xml"))
      response.setContentType("text/xml");
    else if (outputFormat.equals("html"))
      response.setContentType("text/html");
    else 
      response.setContentType("text/xml");
    PrintWriter out = response.getWriter();
    if (query == null) {
      out.print("no query specified: please set parameter \"query\"");
      out.close();
      return;
    }
    try {
      Date begin = new Date();
      IndexHandler indexHandler = IndexHandler.getInstance();
      boolean translateBool = false;
      if (translate != null && translate.equals("true"))
        translateBool = true;
      boolean withHitHighlights = false;
      if (query.contains("tokenOrig:") || query.contains("tokenMorph:") || query.contains("tokenReg:") || query.contains("tokenNorm:"))
        withHitHighlights = true;
      Hits hits = indexHandler.queryDocuments(query, sortFields, language, from, to, withHitHighlights, translateBool);
      ArrayList<Document> docs = null;
      if (hits != null)
        docs = hits.getHits();
      int hitsSize = -1;
      int docsSize = -1;
      if (hits != null)
        hitsSize = hits.getSize();
      if (docs != null)
        docsSize = docs.size();
      Date end = new Date();
      long elapsedTime = end.getTime() - begin.getTime();
      if (outputFormat.equals("xml")) {
        out.print("<result>");
        out.print("<query>");
        out.print("<queryText>" + query + "</queryText>");
        out.print("<resultPage>" + page + "</resultPage>");
        out.print("<resultPageSize>" + pageSize + "</resultPageSize>");
        out.print("</query>");
        out.print("<hitsSize>" + hitsSize + "</hitsSize>");
        out.print("<hits>");
        for (int i=0; i<docsSize; i++) {
          Document doc = docs.get(i);
          out.print("<doc>");
          String docId = doc.getFieldable("docId").stringValue();
          out.print("<docId>" + docId + "</docId>");
          Fieldable docCollectionNamesField = doc.getFieldable("collectionNames");
          if (docCollectionNamesField != null) {
            String docCollectionNames = docCollectionNamesField.stringValue();
            out.print("<collectionName>" + docCollectionNames + "</collectionName>");
          }
          ArrayList<String> hitFragments = doc.getHitFragments();
          if (hitFragments != null) {
            out.print("<hitFragments>");
            for (int j=0; j<hitFragments.size(); j++) {
              String hitFragment = hitFragments.get(j);
              out.print("<hitFragment>" + hitFragment + "</hitFragment>");
            }
            out.print("</hitFragments>");
          }
          out.print("</doc>");
        }
        out.print("</hits>");
        out.print("<executionTime>" + elapsedTime + "</executionTime>");
        out.print("</result>");
      } else if (outputFormat.equals("html")) {
        StringBuilder htmlStrBuilder = new StringBuilder();
        String baseUrl = getBaseUrl(request);
        String cssUrl = baseUrl + "/css/page.css";
        htmlStrBuilder.append("<?xml version=\"1.0\" encoding=\"UTF-8\"?><!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">");
        htmlStrBuilder.append("<html>");
        htmlStrBuilder.append("<head>");
        htmlStrBuilder.append("<title>Query: " + query + "</title>");
        htmlStrBuilder.append("<link rel=\"stylesheet\" type=\"text/css\" href=\"" + cssUrl + "\"/>");
        htmlStrBuilder.append("</head>");
        htmlStrBuilder.append("<body>");
        htmlStrBuilder.append("<table align=\"right\" valign=\"top\">");
        htmlStrBuilder.append("<td>[<i>This is a MPIWG CMS technology service</i>] <a href=\"/mpiwg-mpdl-cms-web/index.html\"><img src=\"/mpiwg-mpdl-cms-web/images/info.png\" valign=\"bottom\" width=\"15\" height=\"15\" border=\"0\" alt=\"MPIWG CMS service\"/></a></td>");
        htmlStrBuilder.append("</table>");
        htmlStrBuilder.append("<p/>");
        String luceneQueryStr = query;
        Query luceneQuery = hits.getQuery();
        if (query != null)
          luceneQueryStr = luceneQuery.toString();
        String sortByStr = sortBy;
        if (sortBy == null)
          sortByStr = "";
        htmlStrBuilder.append("<h4>Query: " + luceneQueryStr + ", sorted by: " + sortByStr + "</h4>");
        htmlStrBuilder.append("<form action=\"QueryDocuments\" method=\"get\">");
        htmlStrBuilder.append("<input type=\"hidden\" name=\"query\" value=\"" + query + "\"/>");
        if (translate != null)
          htmlStrBuilder.append("<input type=\"hidden\" name=\"translate\" value=\"" + translate + "\"/>");
        if (language != null)
          htmlStrBuilder.append("<input type=\"hidden\" name=\"language\" value=\"" + language + "\"/>");
        htmlStrBuilder.append("<input type=\"hidden\" name=\"page\" id=\"pageId\" value=\"" + page + "\"/>");
        htmlStrBuilder.append("<input type=\"hidden\" name=\"sortBy\" id=\"sortById\" value=\"" + sortByStr + "\"/>");
        htmlStrBuilder.append("<input type=\"submit\" id=\"submitId\" style=\"position: absolute; left: -9999px\"/>");
        htmlStrBuilder.append("<table>");
        htmlStrBuilder.append("<colgroup>");
        htmlStrBuilder.append("<col width=\"3%\"/>");
        htmlStrBuilder.append("<col width=\"7%\"/>");
        htmlStrBuilder.append("<col width=\"3%\"/>");
        htmlStrBuilder.append("<col width=\"12%\"/>");
        htmlStrBuilder.append("<col width=\"70%\"/>");
        htmlStrBuilder.append("</colgroup>");
        htmlStrBuilder.append("<tr>");
        int countPages = hitsSize / 10 + 1;
        if (hitsSize % 10 == 0) // modulo operator: e.g. 280 % 10 is 0
          countPages = hitsSize / 10;
        int pageLeft = page - 1;
        if (page == 1)
          pageLeft = 1;
        int pageRight = page + 1; 
        if (page == countPages)
          pageRight = countPages;
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\"><button onclick=\"document.getElementById('pageId').value=" + pageLeft + "\" style=\"background:none;border:none;\"><img src=\"../images/left.gif\"/></button></td>");
        htmlStrBuilder.append("<td align=\"middle\" valign=\"top\" nowrap=\"true\">" + page + " / " + countPages + "</td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\"><button onclick=\"document.getElementById('pageId').value=" + pageRight + "\" style=\"background:none;border:none;\"><img src=\"../images/right.gif\"/></button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\" nowrap=\"true\">Page: <input type=\"text\" size=\"3\" value=\"" + page + "\" id=\"pageTextId\" onkeydown=\"if (event.keyCode == 13) {document.getElementById('pageId').value=document.getElementById('pageTextId').value; document.getElementById('submitId').click();}\"/></td>");
        int fromDisplay = from + 1;
        int toDisplay = to + 1;
        if (hitsSize < to)
          toDisplay = hitsSize;
        htmlStrBuilder.append("<td align=\"right\" valign=\"top\">" + fromDisplay + " - " + toDisplay + " of " + hitsSize + " documents" + "</td>");
        htmlStrBuilder.append("</tr>");
        htmlStrBuilder.append("</table>");
        htmlStrBuilder.append("<p/>");
        htmlStrBuilder.append("<table width=\"100%\" align=\"right\" border=\"2\" rules=\"groups\">");
        htmlStrBuilder.append("<colgroup>");
        htmlStrBuilder.append("<col width=\"3%\"/>");
        htmlStrBuilder.append("<col width=\"15%\"/>");
        htmlStrBuilder.append("<col width=\"45%\"/>");
        htmlStrBuilder.append("<col width=\"10%\"/>");
        htmlStrBuilder.append("<col width=\"5%\"/>");
        htmlStrBuilder.append("<col width=\"10%\"/>");
        htmlStrBuilder.append("<col width=\"6%\"/>");
        htmlStrBuilder.append("<col width=\"5%\"/>");
        htmlStrBuilder.append("<col width=\"4%\"/>");
        htmlStrBuilder.append("</colgroup>");
        htmlStrBuilder.append("<thead>");
        htmlStrBuilder.append("<tr>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\" style=\"font-weight:bold;\">" + "No" + "</td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='author'\" style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Author" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='title'\"  style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Title" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='publisher'\"  style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Place" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='date'\"  style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Year" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='docId'\" style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Id" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='lastModified'\" style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Last modified" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='language'\" style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Language" + "</button></td>");
        htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + "<button onclick=\"document.getElementById('sortById').value='schemaName'\" style=\"padding:0px;font-weight:bold;font-size:14px;background:none;border:none;\">" + "Schema" + "</button></td>");
        htmlStrBuilder.append("</tr>");
        htmlStrBuilder.append("</thead>");
        htmlStrBuilder.append("<tbody>");
        for (int i=0; i<docsSize; i++) {
          Document doc = docs.get(i);
          htmlStrBuilder.append("<tr valign=\"top\">");
          int num = (page - 1) * pageSize + i + 1;
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + num + ". " + "</td>");
          Fieldable authorField = doc.getFieldable("author");
          String author = "";
          if (authorField != null)
            author = authorField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + author + "</td>");
          Fieldable titleField = doc.getFieldable("title");
          String title = "";
          if (titleField != null)
            title = titleField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + title + "</td>");
          Fieldable publisherField = doc.getFieldable("publisher");
          String publisher = "";
          if (publisherField != null)
            publisher = publisherField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + publisher + "</td>");
          Fieldable yearField = doc.getFieldable("date");
          String year = "";
          if (yearField != null)
            year = yearField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + year + "</td>");
          String docId = doc.getFieldable("docId").stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + docId + "</td>");
          Fieldable lastModifiedField = doc.getFieldable("lastModified");
          String lastModified = "";
          if (lastModifiedField != null)
            lastModified = lastModifiedField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + lastModified + "</td>");
          Fieldable languageField = doc.getFieldable("language");
          String lang = "";
          if (languageField != null)
            lang = languageField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\" style=\"padding-left:5px\">" + lang + "</td>");
          Fieldable schemaNameField = doc.getFieldable("schemaName");
          String schemaName = "";
          if (schemaNameField != null)
            schemaName = schemaNameField.stringValue();
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\">" + schemaName + "</td>");
          htmlStrBuilder.append("</tr>");
          // Link row
          htmlStrBuilder.append("<tr valign=\"top\">");
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\"></td>");
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\" colspan=\"8\">");
          Fieldable echoIdField = doc.getFieldable("echoId");
          String echoId = null;
          if (echoIdField != null)
            echoId = echoIdField.stringValue();
          String urlDocuView = "http://echo.mpiwg-berlin.mpg.de/ECHOdocuView?url=" + echoId;
          if (echoId == null)
            urlDocuView = "http://echo.mpiwg-berlin.mpg.de/";
          htmlStrBuilder.append("<img src=\"/mpiwg-mpdl-cms-web/images/book.png\" width=\"15\" height=\"15\" border=\"0\"/>" + " <a href=\"" + urlDocuView + "\">Full view</a>");
          htmlStrBuilder.append(", " + "<a href=\"/mpiwg-mpdl-cms-web/query/GetPage?docId=" + docId + "\">Lite view</a>");
          htmlStrBuilder.append("</td>");
          htmlStrBuilder.append("</tr>");
          htmlStrBuilder.append("<tr valign=\"top\">");
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\"></td>");
          htmlStrBuilder.append("<td align=\"left\" valign=\"top\" colspan=\"8\">");
          htmlStrBuilder.append("<img src=\"/mpiwg-mpdl-cms-web/images/download.png\" width=\"15\" height=\"15\" border=\"0\"/>" + " Download: <a href=\"/mpiwg-mpdl-cms-web/doc/GetDocument?id=" + docId + "\">XML</a>");
          DocumentHandler docHandler = new DocumentHandler();
          String destFileNamePdf = docHandler.getFullFileName(docId, "pdf");
          String destFileNameHtml = docHandler.getFullFileName(docId, "html");
          int lastDot = docId.lastIndexOf(".");
          String docIdWithoutExtension = docId.substring(0, lastDot);
          File destFilePdf = new File(destFileNamePdf);
          File destFileHtml = new File(destFileNameHtml);
          if (destFilePdf.exists())
            htmlStrBuilder.append(", " + "<a href=\"/mpiwg-mpdl-cms-web/doc/GetDocument?id=" + docIdWithoutExtension + ".pdf" + "\">PDF</a>");
          if (destFileHtml.exists())
            htmlStrBuilder.append(", " + "<a href=\"/mpiwg-mpdl-cms-web/doc/GetDocument?id=" + docIdWithoutExtension + ".html" + "\">HTML</a>");
          htmlStrBuilder.append("</td>");
          htmlStrBuilder.append("</tr>");
          // hit fragments row
          ArrayList<String> hitFragments = doc.getHitFragments();
          if (hitFragments != null) {
            StringBuilder hitFragmentsStrBuilder = new StringBuilder();
            hitFragmentsStrBuilder.append("<b>Hit summary: </b>");
            hitFragmentsStrBuilder.append("(...) ");
            for (int j=0; j<hitFragments.size(); j++) {
              String hitFragment = hitFragments.get(j);
              hitFragmentsStrBuilder.append(hitFragment + " (...) ");
            }
            htmlStrBuilder.append("<tr valign=\"top\">");
            htmlStrBuilder.append("<td align=\"left\" valign=\"top\"></td>");
            htmlStrBuilder.append("<td align=\"left\" valign=\"top\" colspan=\"8\">" + hitFragmentsStrBuilder.toString() + "</td>");
            htmlStrBuilder.append("</tr>");
          }
        }
        htmlStrBuilder.append("</tbody>");
        htmlStrBuilder.append("</table>");
        htmlStrBuilder.append("</form>");
        htmlStrBuilder.append("<p/>");
        htmlStrBuilder.append("Elapsed time: " + elapsedTime + " ms");
        htmlStrBuilder.append("</body>");
        htmlStrBuilder.append("</html>");
        out.print(htmlStrBuilder.toString());
      }
      out.close();
    } catch (Exception e) {
      throw new ServletException(e);
    }
  }

  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    doGet(request, response);
  }  

  private String getBaseUrl(HttpServletRequest request) {
    return getServerUrl(request) + request.getContextPath();
  }

  private String getServerUrl(HttpServletRequest request) {
    if ( ( request.getServerPort() == 80 ) || ( request.getServerPort() == 443 ) )
      return request.getScheme() + "://" + request.getServerName();
    else
      return request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort();
  }

}