Fix #550 and Improve KwikExtractor Decrypt Function (#551)

* Improve KwikExtractor Decrypt Function

- Optimize and improve performance of KwikExtractor decrypt functionality

* Fix issue #550

* Update version

src/en/animepahe/build.gradle

@@ -1,7 +1,7 @@
 ext {
     extName = 'AnimePahe'
     extClass = '.AnimePahe'
-    extVersionCode = 27
+    extVersionCode = 28
 }
 
 apply from: "$rootDir/common.gradle"

src/en/animepahe/src/eu/kanade/tachiyomi/animeextension/en/animepahe/AnimePahe.kt

@@ -19,9 +19,6 @@ import eu.kanade.tachiyomi.animesource.online.AnimeHttpSource
 import eu.kanade.tachiyomi.network.GET
 import eu.kanade.tachiyomi.util.asJsoup
 import eu.kanade.tachiyomi.util.parseAs
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.runBlocking
-import kotlinx.coroutines.withContext
 import kotlinx.serialization.json.Json
 import okhttp3.Headers
 import okhttp3.Request
@@ -67,16 +64,8 @@ class AnimePahe : ConfigurableAnimeSource, AnimeHttpSource() {
      * @see episodeListRequest
      */
     override fun animeDetailsRequest(anime: SAnime): Request {
-        val animeId = anime.getId()
-        // We're using coroutines here to run it inside another thread and
-        // prevent android.os.NetworkOnMainThreadException when trying to open
-        // webview or share it.
-        val session = runBlocking {
-            withContext(Dispatchers.IO) {
-                fetchSession(anime.title, animeId)
-            }
-        }
-        return GET("$baseUrl/anime/$session?anime_id=$animeId")
+        val session = anime.getSession()
+        return GET("$baseUrl/anime/$session")
     }
 
     override fun animeDetailsParse(response: Response): SAnime {
@@ -106,8 +95,8 @@ class AnimePahe : ConfigurableAnimeSource, AnimeHttpSource() {
             SAnime.create().apply {
                 title = anime.title
                 thumbnail_url = anime.snapshot
-                val animeId = anime.id
-                setUrlWithoutDomain("/anime/?anime_id=$animeId")
+                val sessionId = anime.anime_session
+                setUrlWithoutDomain("/anime/?session_id=$sessionId")
                 artist = anime.fansub
             }
         }
@@ -124,8 +113,8 @@ class AnimePahe : ConfigurableAnimeSource, AnimeHttpSource() {
             SAnime.create().apply {
                 title = anime.title
                 thumbnail_url = anime.poster
-                val animeId = anime.id
-                setUrlWithoutDomain("/anime/?anime_id=$animeId")
+                val sessionId = anime.session
+                setUrlWithoutDomain("/anime/?session_id=$sessionId")
             }
         }
         return AnimesPage(animeList, false)
@@ -146,7 +135,7 @@ class AnimePahe : ConfigurableAnimeSource, AnimeHttpSource() {
      * @see animeDetailsRequest
      */
     override fun episodeListRequest(anime: SAnime): Request {
-        val session = fetchSession(anime.title, anime.getId())
+        val session = anime.getSession()
         return GET("$baseUrl/api?m=release&id=$session&sort=episode_desc&page=1")
     }
 
@@ -310,15 +299,6 @@ class AnimePahe : ConfigurableAnimeSource, AnimeHttpSource() {
     }
 
     // ============================= Utilities ==============================
-    private fun fetchSession(title: String, animeId: String): String {
-        return client.newCall(GET("$baseUrl/api?m=search&q=$title"))
-            .execute()
-            .body.string()
-            .substringAfter("\"id\":$animeId")
-            .substringAfter("\"session\":\"")
-            .substringBefore("\"")
-    }
-
     private fun parseStatus(statusString: String): Int {
         return when (statusString) {
             "Currently Airing" -> SAnime.ONGOING
@@ -327,7 +307,7 @@ class AnimePahe : ConfigurableAnimeSource, AnimeHttpSource() {
         }
     }
 
-    private fun SAnime.getId() = url.substringAfterLast("?anime_id=").substringBefore("\"")
+    private fun SAnime.getSession() = url.substringAfterLast("?session_id=").substringBefore("\"")
 
     private fun String.toDate(): Long {
         return runCatching {

src/en/animepahe/src/eu/kanade/tachiyomi/animeextension/en/animepahe/KwikExtractor.kt

@@ -35,7 +35,6 @@ import okhttp3.FormBody
 import okhttp3.Headers
 import okhttp3.OkHttpClient
 import okhttp3.Response
-import kotlin.math.pow
 
 class KwikExtractor(private val client: OkHttpClient) {
     private var cookies: String = ""
@@ -108,52 +107,25 @@ class KwikExtractor(private val client: OkHttpClient) {
     }
 
     private fun decrypt(fullString: String, key: String, v1: Int, v2: Int): String {
-        var r = ""
+        val keyIndexMap = key.withIndex().associate { it.value to it.index }
+        val sb = StringBuilder()
         var i = 0
+        val toFind = key[v2]
 
         while (i < fullString.length) {
-            var s = ""
-
-            while (fullString[i] != key[v2]) {
-                s += fullString[i]
-                ++i
+            val nextIndex = fullString.indexOf(toFind, i)
+            val decodedCharStr = buildString {
+                for (j in i until nextIndex) {
+                    append(keyIndexMap[fullString[j]] ?: -1)
                 }
-            var j = 0
-
-            while (j < key.length) {
-                s = s.replace(key[j].toString(), j.toString())
-                ++j
-            }
-            r += (getString(s, v2).toInt() - v1).toChar()
-            ++i
-        }
-        return r
             }
 
-    private fun getString(content: String, s1: Int): String {
-        val s2 = 10
-        val characterMap = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ+/"
+            i = nextIndex + 1
 
-        val slice2 = characterMap.slice(0 until s2)
-        var acc: Long = 0
-
-        for ((n, i) in content.reversed().withIndex()) {
-            acc += when (isNumber("$i")) {
-                true -> "$i".toLong()
-                false -> 0L
-            } * s1.toDouble().pow(n.toDouble()).toInt()
+            val decodedChar = (decodedCharStr.toInt(v2) - v1).toChar()
+            sb.append(decodedChar)
         }
 
-        var k = ""
-
-        while (acc > 0) {
-            k = slice2[(acc % s2).toInt()] + k
-            acc = (acc - (acc % s2)) / s2
-        }
-
-        return when (k != "") {
-            true -> k
-            false -> "0"
-        }
+        return sb.toString()
     }
 }

src/en/animepahe/src/eu/kanade/tachiyomi/animeextension/en/animepahe/dto/AnimePaheDto.kt

@@ -23,6 +23,7 @@ data class LatestAnimeDto(
     @SerialName("anime_id")
     val id: Int,
     val fansub: String,
+    val anime_session: String,
 )
 
 @Serializable
@@ -30,6 +31,7 @@ data class SearchResultDto(
     val title: String,
     val poster: String,
     val id: Int,
+    val session: String,
 )
 
 @Serializable