src/main/java/net/pterodactylus/sone/web/SearchPage.java

   1 /*
   2  * Sone - SearchPage.java - Copyright © 2010 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.sone.web;
  19
  20 import java.util.ArrayList;
  21 import java.util.Collection;
  22 import java.util.Collections;
  23 import java.util.Comparator;
  24 import java.util.HashSet;
  25 import java.util.List;
  26 import java.util.Set;
  27 import java.util.logging.Level;
  28 import java.util.logging.Logger;
  29
  30 import net.pterodactylus.sone.data.Post;
  31 import net.pterodactylus.sone.data.Profile;
  32 import net.pterodactylus.sone.data.Profile.Field;
  33 import net.pterodactylus.sone.data.Reply;
  34 import net.pterodactylus.sone.data.Sone;
  35 import net.pterodactylus.util.cache.Cache;
  36 import net.pterodactylus.util.cache.CacheException;
  37 import net.pterodactylus.util.cache.CacheItem;
  38 import net.pterodactylus.util.cache.DefaultCacheItem;
  39 import net.pterodactylus.util.cache.MemoryCache;
  40 import net.pterodactylus.util.cache.ValueRetriever;
  41 import net.pterodactylus.util.collection.Mapper;
  42 import net.pterodactylus.util.collection.Mappers;
  43 import net.pterodactylus.util.collection.Pagination;
  44 import net.pterodactylus.util.collection.TimedMap;
  45 import net.pterodactylus.util.filter.Filter;
  46 import net.pterodactylus.util.filter.Filters;
  47 import net.pterodactylus.util.logging.Logging;
  48 import net.pterodactylus.util.number.Numbers;
  49 import net.pterodactylus.util.template.Template;
  50 import net.pterodactylus.util.template.TemplateContext;
  51 import net.pterodactylus.util.text.StringEscaper;
  52 import net.pterodactylus.util.text.TextException;
  53
  54 /**
  55  * This page lets the user search for posts and replies that contain certain
  56  * words.
  57  *
  58  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  59  */
  60 public class SearchPage extends SoneTemplatePage {
  61
  62         /** The logger. */
  63         private static final Logger logger = Logging.getLogger(SearchPage.class);
  64
  65         /** Short-term cache. */
  66         private final Cache<List<Phrase>, Set<Hit<Post>>> hitCache = new MemoryCache<List<Phrase>, Set<Hit<Post>>>(new ValueRetriever<List<Phrase>, Set<Hit<Post>>>() {
  67
  68                 @SuppressWarnings("synthetic-access")
  69                 public CacheItem<Set<Hit<Post>>> retrieve(List<Phrase> phrases) throws CacheException {
  70                         Set<Post> posts = new HashSet<Post>();
  71                         for (Sone sone : webInterface.getCore().getSones()) {
  72                                 posts.addAll(sone.getPosts());
  73                         }
  74                         return new DefaultCacheItem<Set<Hit<Post>>>(getHits(Filters.filteredSet(posts, Post.FUTURE_POSTS_FILTER), phrases, new PostStringGenerator()));
  75                 }
  76
  77         }, new TimedMap<List<Phrase>, CacheItem<Set<Hit<Post>>>>(300000));
  78
  79         /**
  80          * Creates a new search page.
  81          *
  82          * @param template
  83          *            The template to render
  84          * @param webInterface
  85          *            The Sone web interface
  86          */
  87         public SearchPage(Template template, WebInterface webInterface) {
  88                 super("search.html", template, "Page.Search.Title", webInterface);
  89         }
  90
  91         //
  92         // SONETEMPLATEPAGE METHODS
  93         //
  94
  95         /**
  96          * {@inheritDoc}
  97          */
  98         @Override
  99         protected void processTemplate(Request request, TemplateContext templateContext) throws RedirectException {
 100                 super.processTemplate(request, templateContext);
 101                 String query = request.getHttpRequest().getParam("query").trim();
 102                 if (query.length() == 0) {
 103                         throw new RedirectException("index.html");
 104                 }
 105
 106                 List<Phrase> phrases = parseSearchPhrases(query);
 107                 if (phrases.isEmpty()) {
 108                         throw new RedirectException("index.html");
 109                 }
 110
 111                 Set<Sone> sones = webInterface.getCore().getSones();
 112                 Set<Hit<Sone>> soneHits = getHits(sones, phrases, SoneStringGenerator.COMPLETE_GENERATOR);
 113
 114                 Set<Hit<Post>> postHits;
 115                 try {
 116                         postHits = hitCache.get(phrases);
 117                 } catch (CacheException ce1) {
 118                         /* should never happen. */
 119                         logger.log(Level.SEVERE, "Could not get search results from cache!", ce1);
 120                         postHits = Collections.emptySet();
 121                 }
 122
 123                 /* now filter. */
 124                 soneHits = Filters.filteredSet(soneHits, Hit.POSITIVE_FILTER);
 125                 postHits = Filters.filteredSet(postHits, Hit.POSITIVE_FILTER);
 126
 127                 /* now sort. */
 128                 List<Hit<Sone>> sortedSoneHits = new ArrayList<Hit<Sone>>(soneHits);
 129                 Collections.sort(sortedSoneHits, Hit.DESCENDING_COMPARATOR);
 130                 List<Hit<Post>> sortedPostHits = new ArrayList<Hit<Post>>(postHits);
 131                 Collections.sort(sortedPostHits, Hit.DESCENDING_COMPARATOR);
 132
 133                 /* extract Sones and posts. */
 134                 List<Sone> resultSones = Mappers.mappedList(sortedSoneHits, new HitMapper<Sone>());
 135                 List<Post> resultPosts = Mappers.mappedList(sortedPostHits, new HitMapper<Post>());
 136
 137                 /* pagination. */
 138                 Pagination<Sone> sonePagination = new Pagination<Sone>(resultSones, webInterface.getCore().getPreferences().getPostsPerPage()).setPage(Numbers.safeParseInteger(request.getHttpRequest().getParam("sonePage"), 0));
 139                 Pagination<Post> postPagination = new Pagination<Post>(resultPosts, webInterface.getCore().getPreferences().getPostsPerPage()).setPage(Numbers.safeParseInteger(request.getHttpRequest().getParam("postPage"), 0));
 140
 141                 templateContext.set("sonePagination", sonePagination);
 142                 templateContext.set("soneHits", sonePagination.getItems());
 143                 templateContext.set("postPagination", postPagination);
 144                 templateContext.set("postHits", postPagination.getItems());
 145         }
 146
 147         //
 148         // PRIVATE METHODS
 149         //
 150
 151         /**
 152          * Collects hit information for the given objects. The objects are converted
 153          * to a {@link String} using the given {@link StringGenerator}, and the
 154          * {@link #calculateScore(List, String) calculated score} is stored together
 155          * with the object in a {@link Hit}, and all resulting {@link Hit}s are then
 156          * returned.
 157          *
 158          * @param <T>
 159          *            The type of the objects
 160          * @param objects
 161          *            The objects to search over
 162          * @param phrases
 163          *            The phrases to search for
 164          * @param stringGenerator
 165          *            The string generator for the objects
 166          * @return The hits for the given phrases
 167          */
 168         private <T> Set<Hit<T>> getHits(Collection<T> objects, List<Phrase> phrases, StringGenerator<T> stringGenerator) {
 169                 Set<Hit<T>> hits = new HashSet<Hit<T>>();
 170                 for (T object : objects) {
 171                         String objectString = stringGenerator.generateString(object);
 172                         double score = calculateScore(phrases, objectString);
 173                         hits.add(new Hit<T>(object, score));
 174                 }
 175                 return hits;
 176         }
 177
 178         /**
 179          * Parses the given query into search phrases. The query is split on
 180          * whitespace while allowing to group words using single or double quotes.
 181          * Isolated phrases starting with a “+” are
 182          * {@link Phrase.Optionality#REQUIRED}, phrases with a “-” are
 183          * {@link Phrase.Optionality#FORBIDDEN}.
 184          *
 185          * @param query
 186          *            The query to parse
 187          * @return The parsed phrases
 188          */
 189         private List<Phrase> parseSearchPhrases(String query) {
 190                 List<String> parsedPhrases = null;
 191                 try {
 192                         parsedPhrases = StringEscaper.parseLine(query);
 193                 } catch (TextException te1) {
 194                         /* invalid query. */
 195                         return Collections.emptyList();
 196                 }
 197
 198                 List<Phrase> phrases = new ArrayList<Phrase>();
 199                 for (String phrase : parsedPhrases) {
 200                         if (phrase.startsWith("+")) {
 201                                 if (phrase.length() > 1) {
 202                                         phrases.add(new Phrase(phrase.substring(1), Phrase.Optionality.REQUIRED));
 203                                 } else {
 204                                         phrases.add(new Phrase("+", Phrase.Optionality.OPTIONAL));
 205                                 }
 206                         } else if (phrase.startsWith("-")) {
 207                                 if (phrase.length() > 1) {
 208                                         phrases.add(new Phrase(phrase.substring(1), Phrase.Optionality.FORBIDDEN));
 209                                 } else {
 210                                         phrases.add(new Phrase("-", Phrase.Optionality.OPTIONAL));
 211                                 }
 212                         } else {
 213                                 phrases.add(new Phrase(phrase, Phrase.Optionality.OPTIONAL));
 214                         }
 215                 }
 216                 return phrases;
 217         }
 218
 219         /**
 220          * Calculates the score for the given expression when using the given
 221          * phrases.
 222          *
 223          * @param phrases
 224          *            The phrases to search for
 225          * @param expression
 226          *            The expression to search
 227          * @return The score of the expression
 228          */
 229         private double calculateScore(List<Phrase> phrases, String expression) {
 230                 logger.log(Level.FINEST, "Calculating Score for “%s”…", expression);
 231                 double optionalHits = 0;
 232                 double requiredHits = 0;
 233                 int forbiddenHits = 0;
 234                 int requiredPhrases = 0;
 235                 for (Phrase phrase : phrases) {
 236                         String phraseString = phrase.getPhrase().toLowerCase();
 237                         if (phrase.getOptionality() == Phrase.Optionality.REQUIRED) {
 238                                 ++requiredPhrases;
 239                         }
 240                         int matches = 0;
 241                         int index = 0;
 242                         double score = 0;
 243                         while (index < expression.length()) {
 244                                 int position = expression.toLowerCase().indexOf(phraseString, index);
 245                                 if (position == -1) {
 246                                         break;
 247                                 }
 248                                 score += Math.pow(1 - position / (double) expression.length(), 2);
 249                                 index = position + phraseString.length();
 250                                 logger.log(Level.FINEST, "Got hit at position %d.", position);
 251                                 ++matches;
 252                         }
 253                         logger.log(Level.FINEST, "Score: %f", score);
 254                         if (matches == 0) {
 255                                 continue;
 256                         }
 257                         if (phrase.getOptionality() == Phrase.Optionality.REQUIRED) {
 258                                 requiredHits += score;
 259                         }
 260                         if (phrase.getOptionality() == Phrase.Optionality.OPTIONAL) {
 261                                 optionalHits += score;
 262                         }
 263                         if (phrase.getOptionality() == Phrase.Optionality.FORBIDDEN) {
 264                                 forbiddenHits += matches;
 265                         }
 266                 }
 267                 return requiredHits * 3 + optionalHits + (requiredHits - requiredPhrases) * 5 - (forbiddenHits * 2);
 268         }
 269
 270         /**
 271          * Converts a given object into a {@link String}.
 272          *
 273          * @param <T>
 274          *            The type of the objects
 275          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 276          */
 277         private static interface StringGenerator<T> {
 278
 279                 /**
 280                  * Generates a {@link String} for the given object.
 281                  *
 282                  * @param object
 283                  *            The object to generate the {@link String} for
 284                  * @return The generated {@link String}
 285                  */
 286                 public String generateString(T object);
 287
 288         }
 289
 290         /**
 291          * Generates a {@link String} from a {@link Sone}, concatenating the name of
 292          * the Sone and all {@link Profile} {@link Field} values.
 293          *
 294          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 295          */
 296         private static class SoneStringGenerator implements StringGenerator<Sone> {
 297
 298                 /** A static instance of a complete Sone string generator. */
 299                 public static final SoneStringGenerator COMPLETE_GENERATOR = new SoneStringGenerator(true);
 300
 301                 /**
 302                  * A static instance of a Sone string generator that will only use the
 303                  * name of the Sone.
 304                  */
 305                 public static final SoneStringGenerator NAME_GENERATOR = new SoneStringGenerator(false);
 306
 307                 /** Whether to generate a string from all data of a Sone. */
 308                 private final boolean complete;
 309
 310                 /**
 311                  * Creates a new Sone string generator.
 312                  *
 313                  * @param complete
 314                  *            {@code true} to use the profile’s fields, {@code false} to
 315                  *            not to use the profile‘s fields
 316                  */
 317                 private SoneStringGenerator(boolean complete) {
 318                         this.complete = complete;
 319                 }
 320
 321                 /**
 322                  * {@inheritDoc}
 323                  */
 324                 @Override
 325                 public String generateString(Sone sone) {
 326                         StringBuilder soneString = new StringBuilder();
 327                         soneString.append(sone.getName());
 328                         Profile soneProfile = sone.getProfile();
 329                         if (soneProfile.getFirstName() != null) {
 330                                 soneString.append(' ').append(soneProfile.getFirstName());
 331                         }
 332                         if (soneProfile.getMiddleName() != null) {
 333                                 soneString.append(' ').append(soneProfile.getMiddleName());
 334                         }
 335                         if (soneProfile.getLastName() != null) {
 336                                 soneString.append(' ').append(soneProfile.getLastName());
 337                         }
 338                         if (complete) {
 339                                 for (Field field : soneProfile.getFields()) {
 340                                         soneString.append(' ').append(field.getValue());
 341                                 }
 342                         }
 343                         return soneString.toString();
 344                 }
 345
 346         }
 347
 348         /**
 349          * Generates a {@link String} from a {@link Post}, concatenating the text of
 350          * the post, the text of all {@link Reply}s, and the name of all
 351          * {@link Sone}s that have replied.
 352          *
 353          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 354          */
 355         private class PostStringGenerator implements StringGenerator<Post> {
 356
 357                 /**
 358                  * {@inheritDoc}
 359                  */
 360                 @Override
 361                 public String generateString(Post post) {
 362                         StringBuilder postString = new StringBuilder();
 363                         postString.append(post.getText());
 364                         if (post.getRecipient() != null) {
 365                                 postString.append(' ').append(SoneStringGenerator.NAME_GENERATOR.generateString(post.getRecipient()));
 366                         }
 367                         for (Reply reply : Filters.filteredList(webInterface.getCore().getReplies(post), Reply.FUTURE_REPLIES_FILTER)) {
 368                                 postString.append(' ').append(SoneStringGenerator.NAME_GENERATOR.generateString(reply.getSone()));
 369                                 postString.append(' ').append(reply.getText());
 370                         }
 371                         return postString.toString();
 372                 }
 373
 374         }
 375
 376         /**
 377          * A search phrase.
 378          *
 379          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 380          */
 381         private static class Phrase {
 382
 383                 /**
 384                  * The optionality of a search phrase.
 385                  *
 386                  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’
 387                  *         Roden</a>
 388                  */
 389                 public enum Optionality {
 390
 391                         /** The phrase is optional. */
 392                         OPTIONAL,
 393
 394                         /** The phrase is required. */
 395                         REQUIRED,
 396
 397                         /** The phrase is forbidden. */
 398                         FORBIDDEN
 399
 400                 }
 401
 402                 /** The phrase to search for. */
 403                 private final String phrase;
 404
 405                 /** The optionality of the phrase. */
 406                 private final Optionality optionality;
 407
 408                 /**
 409                  * Creates a new phrase.
 410                  *
 411                  * @param phrase
 412                  *            The phrase to search for
 413                  * @param optionality
 414                  *            The optionality of the phrase
 415                  */
 416                 public Phrase(String phrase, Optionality optionality) {
 417                         this.optionality = optionality;
 418                         this.phrase = phrase;
 419                 }
 420
 421                 /**
 422                  * Returns the phrase to search for.
 423                  *
 424                  * @return The phrase to search for
 425                  */
 426                 public String getPhrase() {
 427                         return phrase;
 428                 }
 429
 430                 /**
 431                  * Returns the optionality of the phrase.
 432                  *
 433                  * @return The optionality of the phrase
 434                  */
 435                 public Optionality getOptionality() {
 436                         return optionality;
 437                 }
 438
 439                 //
 440                 // OBJECT METHODS
 441                 //
 442
 443                 /**
 444                  * {@inheritDoc}
 445                  */
 446                 @Override
 447                 public int hashCode() {
 448                         return phrase.hashCode() ^ ((optionality == Optionality.FORBIDDEN) ? (0xaaaaaaaa) : ((optionality == Optionality.REQUIRED) ? 0x55555555 : 0));
 449                 }
 450
 451                 /**
 452                  * {@inheritDoc}
 453                  */
 454                 @Override
 455                 public boolean equals(Object object) {
 456                         if (!(object instanceof Phrase)) {
 457                                 return false;
 458                         }
 459                         Phrase phrase = (Phrase) object;
 460                         return (this.optionality == phrase.optionality) && this.phrase.equals(phrase.phrase);
 461                 }
 462
 463         }
 464
 465         /**
 466          * A hit consists of a searched object and the score it got for the phrases
 467          * of the search.
 468          *
 469          * @see SearchPage#calculateScore(List, String)
 470          * @param <T>
 471          *            The type of the searched object
 472          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 473          */
 474         private static class Hit<T> {
 475
 476                 /** Filter for {@link Hit}s with a score of more than 0. */
 477                 public static final Filter<Hit<?>> POSITIVE_FILTER = new Filter<Hit<?>>() {
 478
 479                         @Override
 480                         public boolean filterObject(Hit<?> hit) {
 481                                 return hit.getScore() > 0;
 482                         }
 483
 484                 };
 485
 486                 /** Comparator that sorts {@link Hit}s descending by score. */
 487                 public static final Comparator<Hit<?>> DESCENDING_COMPARATOR = new Comparator<Hit<?>>() {
 488
 489                         @Override
 490                         public int compare(Hit<?> leftHit, Hit<?> rightHit) {
 491                                 return (rightHit.getScore() < leftHit.getScore()) ? -1 : ((rightHit.getScore() > leftHit.getScore()) ? 1 : 0);
 492                         }
 493
 494                 };
 495
 496                 /** The object that was searched. */
 497                 private final T object;
 498
 499                 /** The score of the object. */
 500                 private final double score;
 501
 502                 /**
 503                  * Creates a new hit.
 504                  *
 505                  * @param object
 506                  *            The object that was searched
 507                  * @param score
 508                  *            The score of the object
 509                  */
 510                 public Hit(T object, double score) {
 511                         this.object = object;
 512                         this.score = score;
 513                 }
 514
 515                 /**
 516                  * Returns the object that was searched.
 517                  *
 518                  * @return The object that was searched
 519                  */
 520                 public T getObject() {
 521                         return object;
 522                 }
 523
 524                 /**
 525                  * Returns the score of the object.
 526                  *
 527                  * @return The score of the object
 528                  */
 529                 public double getScore() {
 530                         return score;
 531                 }
 532
 533         }
 534
 535         /**
 536          * Extracts the object from a {@link Hit}.
 537          *
 538          * @param <T>
 539          *            The type of the object to extract
 540          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 541          */
 542         public static class HitMapper<T> implements Mapper<Hit<T>, T> {
 543
 544                 /**
 545                  * {@inheritDoc}
 546                  */
 547                 @Override
 548                 public T map(Hit<T> input) {
 549                         return input.getObject();
 550                 }
 551
 552         }
 553
 554 }