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