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