Android/r2-streamer/r2-server/src/main/java/org/readium/r2_streamer/server/handler/SearchQueryHandler.java

   1 package org.readium.r2_streamer.server.handler;
   2
   3 //import android.support.annotation.Nullable;
   4 //import android.util.Log;
   5
   6 import org.readium.r2_streamer.fetcher.EpubFetcher;
   7 import org.readium.r2_streamer.fetcher.EpubFetcherException;
   8 import org.readium.r2_streamer.model.publication.link.Link;
   9 import org.readium.r2_streamer.model.searcher.SearchQueryResults;
  10 import org.readium.r2_streamer.model.searcher.SearchResult;
  11 import org.readium.r2_streamer.server.ResponseStatus;
  12 import com.fasterxml.jackson.core.JsonProcessingException;
  13 import com.fasterxml.jackson.databind.ObjectMapper;
  14
  15 import org.jsoup.Jsoup;
  16 import org.jsoup.nodes.Document;
  17 import org.jsoup.nodes.Element;
  18
  19 import java.util.Map;
  20 import java.util.regex.Matcher;
  21 import java.util.regex.Pattern;
  22
  23 import fi.iki.elonen.NanoHTTPD;
  24 import fi.iki.elonen.NanoHTTPD.IHTTPSession;
  25 import fi.iki.elonen.NanoHTTPD.Method;
  26 import fi.iki.elonen.NanoHTTPD.Response;
  27 import fi.iki.elonen.NanoHTTPD.Response.IStatus;
  28 import fi.iki.elonen.NanoHTTPD.Response.Status;
  29 import fi.iki.elonen.router.RouterNanoHTTPD.DefaultHandler;
  30 import fi.iki.elonen.router.RouterNanoHTTPD.UriResource;
  31
  32 /**
  33  * Created by Shrikant Badwaik on 17-Feb-17.
  34  */
  35
  36 public class SearchQueryHandler extends DefaultHandler {
  37     private static final String TAG = "SearchQueryHandler";
  38     private Response response;
  39
  40     public SearchQueryHandler() {
  41     }
  42
  43     @Override
  44     public String getText() {
  45         return ResponseStatus.FAILURE_RESPONSE;
  46     }
  47
  48     @Override
  49     public String getMimeType() {
  50         return "application/json";
  51     }
  52
  53     @Override
  54     public IStatus getStatus() {
  55         return Status.NOT_ACCEPTABLE;
  56     }
  57
  58     @Override
  59     public Response get(UriResource uriResource, Map<String, String> urlParams, IHTTPSession session) {
  60         Method method = session.getMethod();
  61         String uri = session.getUri();
  62
  63         //Log.d(TAG, "Method: " + method + ", Url: " + uri);
  64
  65         try {
  66             EpubFetcher fetcher = uriResource.initParameter(EpubFetcher.class);
  67
  68             String queryParameter = session.getQueryParameterString();
  69             int startIndex = queryParameter.indexOf("=");
  70             String searchQueryPath = queryParameter.substring(startIndex + 1);
  71
  72             SearchQueryResults searchQueryResults = new SearchQueryResults();
  73             for (Link link : fetcher.publication.spines) {
  74                 String htmlText = fetcher.getData(link.getHref());
  75                 if (searchQueryPath.contains("%20")) {
  76                     searchQueryPath = searchQueryPath.replaceAll("%20", " ");
  77                 }
  78                 Pattern pattern = Pattern.compile(searchQueryPath, Pattern.CASE_INSENSITIVE);
  79                 Matcher matcher = pattern.matcher(htmlText);
  80                 while (matcher.find()) {
  81                     int start = matcher.start();
  82
  83                     String prev = getTextBefore(start, htmlText);
  84                     //String prev = htmlText.substring(start - 20, start);
  85                     String next = getTextAfter(start, searchQueryPath, htmlText);
  86                     //String next = htmlText.substring(start + searchQueryPath.length(), (start + searchQueryPath.length()) + 20);
  87                     String match = prev.concat(searchQueryPath).concat(next);
  88
  89                     SearchResult searchResult = new SearchResult();
  90                     searchResult.setSearchIndex(start);
  91                     searchResult.setResource(link.getHref());
  92                     searchResult.setSearchQuery(searchQueryPath);
  93                     searchResult.setMatchString(match);
  94                     searchResult.setTextBefore(prev);
  95                     searchResult.setTextAfter(next);
  96
  97                     String title = parseChapterTitle(htmlText);
  98                     if (title != null) {
  99                         searchResult.setTitle(title);
 100                     } else {
 101                         searchResult.setTitle("Title not available");
 102                     }
 103                     searchQueryResults.searchResultList.add(searchResult);
 104                 }
 105             }
 106             ObjectMapper objectMapper = new ObjectMapper();
 107             String json = objectMapper.writeValueAsString(searchQueryResults);
 108             response = NanoHTTPD.newFixedLengthResponse(Status.OK, getMimeType(), json);
 109             return response;
 110         } catch (EpubFetcherException | JsonProcessingException e) {
 111             e.printStackTrace();
 112             return NanoHTTPD.newFixedLengthResponse(Status.INTERNAL_ERROR, getMimeType(), ResponseStatus.FAILURE_RESPONSE);
 113         }
 114     }
 115
 116     //@Nullable
 117     private String parseChapterTitle(String searchData) {
 118         Document document = Jsoup.parse(searchData);
 119         Element h1Element = document.select("h1").first();
 120         if (h1Element != null) {
 121             return h1Element.text();
 122         } else {
 123             Element h2Element = document.select("h2").first();
 124             if (h2Element != null) {
 125                 return h2Element.text();
 126             } else {
 127                 Element titleElement = document.select("title").first();
 128                 if (titleElement != null) {
 129                     return titleElement.text();
 130                 }
 131             }
 132         }
 133         return null;
 134     }
 135
 136     private String getTextBefore(int start, String htmlString) {
 137         int beginIndex = start - 20;
 138         if (beginIndex >= 0 && beginIndex < htmlString.length()) {
 139             return htmlString.substring(beginIndex, start);
 140         } else {
 141             return htmlString.substring(0, start);
 142         }
 143     }
 144
 145     private String getTextAfter(int start, String searchQueryPath, String htmlString) {
 146         int beginIndex = start + searchQueryPath.length();
 147         if ((beginIndex + 20) > htmlString.length()) {
 148             return htmlString.substring(beginIndex);
 149         } else {
 150             return htmlString.substring(beginIndex, beginIndex + 20);
 151         }
 152     }
 153 }