src/main/kotlin/net/pterodactylus/sone/web/pages/SearchPage.kt

   1 package net.pterodactylus.sone.web.pages
   2
   3 import com.google.common.base.Ticker
   4 import com.google.common.cache.Cache
   5 import com.google.common.cache.CacheBuilder
   6 import freenet.support.Logger
   7 import net.pterodactylus.sone.data.Post
   8 import net.pterodactylus.sone.data.PostReply
   9 import net.pterodactylus.sone.data.Sone
  10 import net.pterodactylus.sone.utils.Pagination
  11 import net.pterodactylus.sone.utils.emptyToNull
  12 import net.pterodactylus.sone.utils.memoize
  13 import net.pterodactylus.sone.utils.paginate
  14 import net.pterodactylus.sone.utils.parameters
  15 import net.pterodactylus.sone.web.WebInterface
  16 import net.pterodactylus.sone.web.page.FreenetRequest
  17 import net.pterodactylus.sone.web.pages.SearchPage.Optionality.FORBIDDEN
  18 import net.pterodactylus.sone.web.pages.SearchPage.Optionality.OPTIONAL
  19 import net.pterodactylus.sone.web.pages.SearchPage.Optionality.REQUIRED
  20 import net.pterodactylus.util.template.Template
  21 import net.pterodactylus.util.template.TemplateContext
  22 import net.pterodactylus.util.text.StringEscaper
  23 import net.pterodactylus.util.text.TextException
  24 import java.util.concurrent.TimeUnit.MINUTES
  25 import javax.inject.Inject
  26
  27 /**
  28  * This page lets the user search for posts and replies that contain certain
  29  * words.
  30  */
  31 class SearchPage(template: Template, webInterface: WebInterface, ticker: Ticker = Ticker.systemTicker()) :
  32                 SoneTemplatePage("search.html", webInterface, template, "Page.Search.Title") {
  33
  34         @Inject constructor(template: Template, webInterface: WebInterface) :
  35                         this(template, webInterface, Ticker.systemTicker())
  36
  37         private val cache: Cache<Iterable<Phrase>, Pagination<Post>> = CacheBuilder.newBuilder().ticker(ticker).expireAfterAccess(5, MINUTES).build()
  38
  39         override fun handleRequest(freenetRequest: FreenetRequest, templateContext: TemplateContext) {
  40                 val startTime = System.currentTimeMillis()
  41                 val phrases = try {
  42                         freenetRequest.parameters["query"].emptyToNull?.parse()
  43                 } catch (te: TextException) {
  44                         redirect("index.html")
  45                 }
  46                                 ?: redirect("index.html")
  47
  48                 when (phrases.size) {
  49                         0 -> redirect("index.html")
  50                         1 -> phrases.first().phrase.also { word ->
  51                                 when {
  52                                         word.removePrefix("sone://").let(webInterface.core::getSone) != null -> redirect("viewSone.html?sone=${word.removePrefix("sone://")}")
  53                                         word.removePrefix("post://").let(webInterface.core::getPost) != null -> redirect("viewPost.html?post=${word.removePrefix("post://")}")
  54                                         word.removePrefix("reply://").let(webInterface.core::getPostReply) != null -> redirect("viewPost.html?post=${word.removePrefix("reply://").let(webInterface.core::getPostReply)?.postId}")
  55                                         word.removePrefix("album://").let(webInterface.core::getAlbum) != null -> redirect("imageBrowser.html?album=${word.removePrefix("album://")}")
  56                                         word.removePrefix("image://").let { webInterface.core.getImage(it, false) } != null -> redirect("imageBrowser.html?image=${word.removePrefix("image://")}")
  57                                 }
  58                         }
  59                 }
  60
  61                 val soneNameCache = { sone: Sone -> sone.names() }.memoize()
  62                 val sonePagination = webInterface.core.sones
  63                                 .scoreAndPaginate(phrases) { it.allText(soneNameCache) }
  64                                 .apply { page = freenetRequest.parameters["sonePage"].emptyToNull?.toIntOrNull() ?: 0 }
  65                 val postPagination = cache.get(phrases) {
  66                         webInterface.core.sones
  67                                         .flatMap(Sone::getPosts)
  68                                         .filter { Post.FUTURE_POSTS_FILTER.apply(it) }
  69                                         .scoreAndPaginate(phrases) { it.allText(soneNameCache) }
  70                 }.apply { page = freenetRequest.parameters["postPage"].emptyToNull?.toIntOrNull() ?: 0 }
  71
  72                 Logger.normal(SearchPage::class.java, "Finished search for “${freenetRequest.parameters["query"]}” in ${System.currentTimeMillis() - startTime}ms.")
  73                 templateContext["sonePagination"] = sonePagination
  74                 templateContext["soneHits"] = sonePagination.items
  75                 templateContext["postPagination"] = postPagination
  76                 templateContext["postHits"] = postPagination.items
  77         }
  78
  79         private fun <T> Iterable<T>.scoreAndPaginate(phrases: Iterable<Phrase>, texter: (T) -> String) =
  80                         map { it to score(texter(it), phrases) }
  81                                         .filter { it.second > 0 }
  82                                         .sortedByDescending { it.second }
  83                                         .map { it.first }
  84                                         .paginate(webInterface.core.preferences.postsPerPage)
  85
  86         private fun Sone.names() =
  87                         with(profile) {
  88                                 listOf(name, firstName, middleName, lastName)
  89                                                 .filterNotNull()
  90                                                 .joinToString("")
  91                         }
  92
  93         private fun Sone.allText(soneNameCache: (Sone) -> String) =
  94                         (soneNameCache(this) + profile.fields.map { "${it.name} ${it.value}" }.joinToString(" ", " ")).toLowerCase()
  95
  96         private fun Post.allText(soneNameCache: (Sone) -> String) =
  97                         (text + recipient.orNull()?.let { " ${soneNameCache(it)}" } + webInterface.core.getReplies(id)
  98                                         .filter { PostReply.FUTURE_REPLY_FILTER.apply(it) }
  99                                         .map { "${soneNameCache(it.sone)} ${it.text}" }.joinToString(" ", " ")).toLowerCase()
 100
 101         private fun score(text: String, phrases: Iterable<Phrase>): Double {
 102                 val requiredPhrases = phrases.count { it.required }
 103                 val requiredHits = phrases.filter(Phrase::required)
 104                                 .map(Phrase::phrase)
 105                                 .flatMap { text.findAll(it) }
 106                                 .map { Math.pow(1 - it / text.length.toDouble(), 2.0) }
 107                                 .sum()
 108                 val optionalHits = phrases.filter(Phrase::optional)
 109                                 .map(Phrase::phrase)
 110                                 .flatMap { text.findAll(it) }
 111                                 .map { Math.pow(1 - it / text.length.toDouble(), 2.0) }
 112                                 .sum()
 113                 val forbiddenHits = phrases.filter(Phrase::forbidden)
 114                                 .map(Phrase::phrase)
 115                                 .map { text.findAll(it).size }
 116                                 .sum()
 117                 return requiredHits * 3 + optionalHits + (requiredHits - requiredPhrases) * 5 - (forbiddenHits * 2)
 118         }
 119
 120         private fun String.findAll(needle: String) =
 121                         generateSequence(indexOf(needle).takeIf { it > -1 }) { lastPosition ->
 122                                 lastPosition
 123                                                 .let { indexOf(needle, it + 1) }
 124                                                 .takeIf { it > -1 }
 125                         }.toList()
 126
 127         private fun String.parse() =
 128                         StringEscaper.parseLine(this)
 129                                         .map(String::toLowerCase)
 130                                         .map {
 131                                                 when {
 132                                                         it == "+" || it == "-" -> Phrase(it, OPTIONAL)
 133                                                         it.startsWith("+") -> Phrase(it.drop(1), REQUIRED)
 134                                                         it.startsWith("-") -> Phrase(it.drop(1), FORBIDDEN)
 135                                                         else -> Phrase(it, OPTIONAL)
 136                                                 }
 137                                         }
 138
 139         private fun redirect(target: String): Nothing = throw RedirectException(target)
 140
 141         enum class Optionality {
 142                 OPTIONAL,
 143                 REQUIRED,
 144                 FORBIDDEN
 145         }
 146
 147         private data class Phrase(val phrase: String, val optionality: Optionality) {
 148                 val required = optionality == REQUIRED
 149                 val forbidden = optionality == FORBIDDEN
 150                 val optional = optionality == OPTIONAL
 151         }
 152
 153 }