/*
* Sone - SearchPage.java - Copyright © 2010 David Roden
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
package net.pterodactylus.sone.web;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
import net.pterodactylus.sone.data.Post;
import net.pterodactylus.sone.data.PostReply;
import net.pterodactylus.sone.data.Profile;
import net.pterodactylus.sone.data.Profile.Field;
import net.pterodactylus.sone.data.Reply;
import net.pterodactylus.sone.data.Sone;
import net.pterodactylus.sone.web.page.FreenetRequest;
import net.pterodactylus.util.cache.Cache;
import net.pterodactylus.util.cache.CacheException;
import net.pterodactylus.util.cache.CacheItem;
import net.pterodactylus.util.cache.DefaultCacheItem;
import net.pterodactylus.util.cache.MemoryCache;
import net.pterodactylus.util.cache.ValueRetriever;
import net.pterodactylus.util.collection.Mapper;
import net.pterodactylus.util.collection.Mappers;
import net.pterodactylus.util.collection.Pagination;
import net.pterodactylus.util.collection.TimedMap;
import net.pterodactylus.util.filter.Filter;
import net.pterodactylus.util.filter.Filters;
import net.pterodactylus.util.logging.Logging;
import net.pterodactylus.util.number.Numbers;
import net.pterodactylus.util.template.Template;
import net.pterodactylus.util.template.TemplateContext;
import net.pterodactylus.util.text.StringEscaper;
import net.pterodactylus.util.text.TextException;
/**
* This page lets the user search for posts and replies that contain certain
* words.
*
* @author David ‘Bombe’ Roden
*/
public class SearchPage extends SoneTemplatePage {
/** The logger. */
private static final Logger logger = Logging.getLogger(SearchPage.class);
/** Short-term cache. */
private final Cache, Set>> hitCache = new MemoryCache, Set>>(new ValueRetriever, Set>>() {
@Override
@SuppressWarnings("synthetic-access")
public CacheItem>> retrieve(List phrases) throws CacheException {
Set posts = new HashSet();
for (Sone sone : webInterface.getCore().getSones()) {
posts.addAll(sone.getPosts());
}
return new DefaultCacheItem>>(getHits(Filters.filteredSet(posts, Post.FUTURE_POSTS_FILTER), phrases, new PostStringGenerator()));
}
}, new TimedMap, CacheItem>>>(300000));
/**
* Creates a new search page.
*
* @param template
* The template to render
* @param webInterface
* The Sone web interface
*/
public SearchPage(Template template, WebInterface webInterface) {
super("search.html", template, "Page.Search.Title", webInterface);
}
//
// SONETEMPLATEPAGE METHODS
//
/**
* {@inheritDoc}
*/
@Override
protected void processTemplate(FreenetRequest request, TemplateContext templateContext) throws RedirectException {
super.processTemplate(request, templateContext);
String query = request.getHttpRequest().getParam("query").trim();
if (query.length() == 0) {
throw new RedirectException("index.html");
}
List phrases = parseSearchPhrases(query);
if (phrases.isEmpty()) {
throw new RedirectException("index.html");
}
Set sones = webInterface.getCore().getSones();
Set> soneHits = getHits(sones, phrases, SoneStringGenerator.COMPLETE_GENERATOR);
Set> postHits;
try {
postHits = hitCache.get(phrases);
} catch (CacheException ce1) {
/* should never happen. */
logger.log(Level.SEVERE, "Could not get search results from cache!", ce1);
postHits = Collections.emptySet();
}
/* now filter. */
soneHits = Filters.filteredSet(soneHits, Hit.POSITIVE_FILTER);
postHits = Filters.filteredSet(postHits, Hit.POSITIVE_FILTER);
/* now sort. */
List> sortedSoneHits = new ArrayList>(soneHits);
Collections.sort(sortedSoneHits, Hit.DESCENDING_COMPARATOR);
List> sortedPostHits = new ArrayList>(postHits);
Collections.sort(sortedPostHits, Hit.DESCENDING_COMPARATOR);
/* extract Sones and posts. */
List resultSones = Mappers.mappedList(sortedSoneHits, new HitMapper());
List resultPosts = Mappers.mappedList(sortedPostHits, new HitMapper());
/* pagination. */
Pagination sonePagination = new Pagination(resultSones, webInterface.getCore().getPreferences().getPostsPerPage()).setPage(Numbers.safeParseInteger(request.getHttpRequest().getParam("sonePage"), 0));
Pagination postPagination = new Pagination(resultPosts, webInterface.getCore().getPreferences().getPostsPerPage()).setPage(Numbers.safeParseInteger(request.getHttpRequest().getParam("postPage"), 0));
templateContext.set("sonePagination", sonePagination);
templateContext.set("soneHits", sonePagination.getItems());
templateContext.set("postPagination", postPagination);
templateContext.set("postHits", postPagination.getItems());
}
//
// PRIVATE METHODS
//
/**
* Collects hit information for the given objects. The objects are converted
* to a {@link String} using the given {@link StringGenerator}, and the
* {@link #calculateScore(List, String) calculated score} is stored together
* with the object in a {@link Hit}, and all resulting {@link Hit}s are then
* returned.
*
* @param
* The type of the objects
* @param objects
* The objects to search over
* @param phrases
* The phrases to search for
* @param stringGenerator
* The string generator for the objects
* @return The hits for the given phrases
*/
private Set> getHits(Collection objects, List phrases, StringGenerator stringGenerator) {
Set> hits = new HashSet>();
for (T object : objects) {
String objectString = stringGenerator.generateString(object);
double score = calculateScore(phrases, objectString);
hits.add(new Hit(object, score));
}
return hits;
}
/**
* Parses the given query into search phrases. The query is split on
* whitespace while allowing to group words using single or double quotes.
* Isolated phrases starting with a “+” are
* {@link Phrase.Optionality#REQUIRED}, phrases with a “-” are
* {@link Phrase.Optionality#FORBIDDEN}.
*
* @param query
* The query to parse
* @return The parsed phrases
*/
private List parseSearchPhrases(String query) {
List parsedPhrases = null;
try {
parsedPhrases = StringEscaper.parseLine(query);
} catch (TextException te1) {
/* invalid query. */
return Collections.emptyList();
}
List phrases = new ArrayList();
for (String phrase : parsedPhrases) {
if (phrase.startsWith("+")) {
if (phrase.length() > 1) {
phrases.add(new Phrase(phrase.substring(1), Phrase.Optionality.REQUIRED));
} else {
phrases.add(new Phrase("+", Phrase.Optionality.OPTIONAL));
}
} else if (phrase.startsWith("-")) {
if (phrase.length() > 1) {
phrases.add(new Phrase(phrase.substring(1), Phrase.Optionality.FORBIDDEN));
} else {
phrases.add(new Phrase("-", Phrase.Optionality.OPTIONAL));
}
} else {
phrases.add(new Phrase(phrase, Phrase.Optionality.OPTIONAL));
}
}
return phrases;
}
/**
* Calculates the score for the given expression when using the given
* phrases.
*
* @param phrases
* The phrases to search for
* @param expression
* The expression to search
* @return The score of the expression
*/
private double calculateScore(List phrases, String expression) {
logger.log(Level.FINEST, String.format("Calculating Score for “%s”…", expression));
double optionalHits = 0;
double requiredHits = 0;
int forbiddenHits = 0;
int requiredPhrases = 0;
for (Phrase phrase : phrases) {
String phraseString = phrase.getPhrase().toLowerCase();
if (phrase.getOptionality() == Phrase.Optionality.REQUIRED) {
++requiredPhrases;
}
int matches = 0;
int index = 0;
double score = 0;
while (index < expression.length()) {
int position = expression.toLowerCase().indexOf(phraseString, index);
if (position == -1) {
break;
}
score += Math.pow(1 - position / (double) expression.length(), 2);
index = position + phraseString.length();
logger.log(Level.FINEST, String.format("Got hit at position %d.", position));
++matches;
}
logger.log(Level.FINEST, String.format("Score: %f", score));
if (matches == 0) {
continue;
}
if (phrase.getOptionality() == Phrase.Optionality.REQUIRED) {
requiredHits += score;
}
if (phrase.getOptionality() == Phrase.Optionality.OPTIONAL) {
optionalHits += score;
}
if (phrase.getOptionality() == Phrase.Optionality.FORBIDDEN) {
forbiddenHits += matches;
}
}
return requiredHits * 3 + optionalHits + (requiredHits - requiredPhrases) * 5 - (forbiddenHits * 2);
}
/**
* Converts a given object into a {@link String}.
*
* @param
* The type of the objects
* @author David ‘Bombe’ Roden
*/
private static interface StringGenerator {
/**
* Generates a {@link String} for the given object.
*
* @param object
* The object to generate the {@link String} for
* @return The generated {@link String}
*/
public String generateString(T object);
}
/**
* Generates a {@link String} from a {@link Sone}, concatenating the name of
* the Sone and all {@link Profile} {@link Field} values.
*
* @author David ‘Bombe’ Roden
*/
private static class SoneStringGenerator implements StringGenerator {
/** A static instance of a complete Sone string generator. */
public static final SoneStringGenerator COMPLETE_GENERATOR = new SoneStringGenerator(true);
/**
* A static instance of a Sone string generator that will only use the
* name of the Sone.
*/
public static final SoneStringGenerator NAME_GENERATOR = new SoneStringGenerator(false);
/** Whether to generate a string from all data of a Sone. */
private final boolean complete;
/**
* Creates a new Sone string generator.
*
* @param complete
* {@code true} to use the profile’s fields, {@code false} to
* not to use the profile‘s fields
*/
private SoneStringGenerator(boolean complete) {
this.complete = complete;
}
/**
* {@inheritDoc}
*/
@Override
public String generateString(Sone sone) {
StringBuilder soneString = new StringBuilder();
soneString.append(sone.getName());
Profile soneProfile = sone.getProfile();
if (soneProfile.getFirstName() != null) {
soneString.append(' ').append(soneProfile.getFirstName());
}
if (soneProfile.getMiddleName() != null) {
soneString.append(' ').append(soneProfile.getMiddleName());
}
if (soneProfile.getLastName() != null) {
soneString.append(' ').append(soneProfile.getLastName());
}
if (complete) {
for (Field field : soneProfile.getFields()) {
soneString.append(' ').append(field.getValue());
}
}
return soneString.toString();
}
}
/**
* Generates a {@link String} from a {@link Post}, concatenating the text of
* the post, the text of all {@link Reply}s, and the name of all
* {@link Sone}s that have replied.
*
* @author David ‘Bombe’ Roden
*/
private class PostStringGenerator implements StringGenerator {
/**
* {@inheritDoc}
*/
@Override
public String generateString(Post post) {
StringBuilder postString = new StringBuilder();
postString.append(post.getText());
if (post.getRecipient() != null) {
postString.append(' ').append(SoneStringGenerator.NAME_GENERATOR.generateString(post.getRecipient()));
}
for (PostReply reply : Filters.filteredList(webInterface.getCore().getReplies(post), Reply.FUTURE_REPLY_FILTER)) {
postString.append(' ').append(SoneStringGenerator.NAME_GENERATOR.generateString(reply.getSone()));
postString.append(' ').append(reply.getText());
}
return postString.toString();
}
}
/**
* A search phrase.
*
* @author David ‘Bombe’ Roden
*/
private static class Phrase {
/**
* The optionality of a search phrase.
*
* @author David ‘Bombe’
* Roden
*/
public enum Optionality {
/** The phrase is optional. */
OPTIONAL,
/** The phrase is required. */
REQUIRED,
/** The phrase is forbidden. */
FORBIDDEN
}
/** The phrase to search for. */
private final String phrase;
/** The optionality of the phrase. */
private final Optionality optionality;
/**
* Creates a new phrase.
*
* @param phrase
* The phrase to search for
* @param optionality
* The optionality of the phrase
*/
public Phrase(String phrase, Optionality optionality) {
this.optionality = optionality;
this.phrase = phrase;
}
/**
* Returns the phrase to search for.
*
* @return The phrase to search for
*/
public String getPhrase() {
return phrase;
}
/**
* Returns the optionality of the phrase.
*
* @return The optionality of the phrase
*/
public Optionality getOptionality() {
return optionality;
}
//
// OBJECT METHODS
//
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
return phrase.hashCode() ^ ((optionality == Optionality.FORBIDDEN) ? (0xaaaaaaaa) : ((optionality == Optionality.REQUIRED) ? 0x55555555 : 0));
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object object) {
if (!(object instanceof Phrase)) {
return false;
}
Phrase phrase = (Phrase) object;
return (this.optionality == phrase.optionality) && this.phrase.equals(phrase.phrase);
}
}
/**
* A hit consists of a searched object and the score it got for the phrases
* of the search.
*
* @see SearchPage#calculateScore(List, String)
* @param
* The type of the searched object
* @author David ‘Bombe’ Roden
*/
private static class Hit {
/** Filter for {@link Hit}s with a score of more than 0. */
public static final Filter> POSITIVE_FILTER = new Filter>() {
@Override
public boolean filterObject(Hit> hit) {
return hit.getScore() > 0;
}
};
/** Comparator that sorts {@link Hit}s descending by score. */
public static final Comparator> DESCENDING_COMPARATOR = new Comparator>() {
@Override
public int compare(Hit> leftHit, Hit> rightHit) {
return (rightHit.getScore() < leftHit.getScore()) ? -1 : ((rightHit.getScore() > leftHit.getScore()) ? 1 : 0);
}
};
/** The object that was searched. */
private final T object;
/** The score of the object. */
private final double score;
/**
* Creates a new hit.
*
* @param object
* The object that was searched
* @param score
* The score of the object
*/
public Hit(T object, double score) {
this.object = object;
this.score = score;
}
/**
* Returns the object that was searched.
*
* @return The object that was searched
*/
public T getObject() {
return object;
}
/**
* Returns the score of the object.
*
* @return The score of the object
*/
public double getScore() {
return score;
}
}
/**
* Extracts the object from a {@link Hit}.
*
* @param
* The type of the object to extract
* @author David ‘Bombe’ Roden
*/
public static class HitMapper implements Mapper, T> {
/**
* {@inheritDoc}
*/
@Override
public T map(Hit input) {
return input.getObject();
}
}
}