Implement Neko similar manga, Mangadex only recommendations

app/build.gradle

@@ -328,6 +328,9 @@ dependencies {
     // RatingBar (SY)
     implementation 'me.zhanghai.android.materialratingbar:library:1.4.0'
 
+    // JsonReader for similar manga
+    implementation 'com.squareup.moshi:moshi:1.11.0'
+
     implementation 'androidx.gridlayout:gridlayout:1.0.0'
 
     implementation 'com.google.guava:guava:29.0-android'

app/src/main/AndroidManifest.xml

@@ -153,6 +153,10 @@
             android:exported="false" />
 
         <!-- EH -->
+        <service
+            android:name="exh.md.similar.SimilarUpdateService"
+            android:exported="false" />
+
         <service
             android:name="exh.eh.EHentaiUpdateWorker"
             android:permission="android.permission.BIND_JOB_SERVICE"

app/src/main/java/eu/kanade/tachiyomi/data/database/DatabaseHelper.kt

@@ -21,6 +21,9 @@ import eu.kanade.tachiyomi.data.database.queries.HistoryQueries
 import eu.kanade.tachiyomi.data.database.queries.MangaCategoryQueries
 import eu.kanade.tachiyomi.data.database.queries.MangaQueries
 import eu.kanade.tachiyomi.data.database.queries.TrackQueries
+import exh.md.similar.sql.mappers.SimilarTypeMapping
+import exh.md.similar.sql.models.MangaSimilar
+import exh.md.similar.sql.queries.SimilarQueries
 import exh.merged.sql.mappers.MergedMangaTypeMapping
 import exh.merged.sql.models.MergedMangaReference
 import exh.merged.sql.queries.MergedQueries
@@ -39,7 +42,7 @@ import io.requery.android.database.sqlite.RequerySQLiteOpenHelperFactory
  * This class provides operations to manage the database through its interfaces.
  */
 open class DatabaseHelper(context: Context) :
-    MangaQueries, ChapterQueries, TrackQueries, CategoryQueries, MangaCategoryQueries, HistoryQueries /* SY --> */, SearchMetadataQueries, SearchTagQueries, SearchTitleQueries, MergedQueries /* SY <-- */ {
+    MangaQueries, ChapterQueries, TrackQueries, CategoryQueries, MangaCategoryQueries, HistoryQueries /* SY --> */, SearchMetadataQueries, SearchTagQueries, SearchTitleQueries, MergedQueries, SimilarQueries /* SY <-- */ {
 
     private val configuration = SupportSQLiteOpenHelper.Configuration.builder(context)
         .name(DbOpenCallback.DATABASE_NAME)
@@ -59,6 +62,7 @@ open class DatabaseHelper(context: Context) :
         .addTypeMapping(SearchTag::class.java, SearchTagTypeMapping())
         .addTypeMapping(SearchTitle::class.java, SearchTitleTypeMapping())
         .addTypeMapping(MergedMangaReference::class.java, MergedMangaTypeMapping())
+        .addTypeMapping(MangaSimilar::class.java, SimilarTypeMapping())
         // SY <--
         .build()
 

app/src/main/java/eu/kanade/tachiyomi/data/database/DbOpenCallback.kt

@@ -8,6 +8,7 @@ import eu.kanade.tachiyomi.data.database.tables.HistoryTable
 import eu.kanade.tachiyomi.data.database.tables.MangaCategoryTable
 import eu.kanade.tachiyomi.data.database.tables.MangaTable
 import eu.kanade.tachiyomi.data.database.tables.TrackTable
+import exh.md.similar.sql.tables.SimilarTable
 import exh.merged.sql.tables.MergedTable
 import exh.metadata.sql.tables.SearchMetadataTable
 import exh.metadata.sql.tables.SearchTagTable
@@ -24,7 +25,7 @@ class DbOpenCallback : SupportSQLiteOpenHelper.Callback(DATABASE_VERSION) {
         /**
          * Version of the database.
          */
-        const val DATABASE_VERSION = /* SY --> */ 4 /* SY <-- */
+        const val DATABASE_VERSION = /* SY --> */ 5 /* SY <-- */
     }
 
     override fun onCreate(db: SupportSQLiteDatabase) = with(db) {
@@ -39,6 +40,7 @@ class DbOpenCallback : SupportSQLiteOpenHelper.Callback(DATABASE_VERSION) {
         execSQL(SearchTagTable.createTableQuery)
         execSQL(SearchTitleTable.createTableQuery)
         execSQL(MergedTable.createTableQuery)
+        execSQL(SimilarTable.createTableQuery)
         // SY <--
 
         // DB indexes
@@ -55,6 +57,7 @@ class DbOpenCallback : SupportSQLiteOpenHelper.Callback(DATABASE_VERSION) {
         execSQL(SearchTitleTable.createMangaIdIndexQuery)
         execSQL(SearchTitleTable.createTitleIndexQuery)
         execSQL(MergedTable.createIndexQuery)
+        execSQL(SimilarTable.createMangaIdIndexQuery)
         // SY <--
     }
 
@@ -71,6 +74,10 @@ class DbOpenCallback : SupportSQLiteOpenHelper.Callback(DATABASE_VERSION) {
             db.execSQL(MergedTable.createTableQuery)
             db.execSQL(MergedTable.createIndexQuery)
         }
+        if (oldVersion < 5) {
+            db.execSQL(SimilarTable.createTableQuery)
+            db.execSQL(SimilarTable.createMangaIdIndexQuery)
+        }
     }
 
     override fun onConfigure(db: SupportSQLiteDatabase) {

app/src/main/java/eu/kanade/tachiyomi/data/notification/NotificationReceiver.kt

@@ -25,6 +25,7 @@ import eu.kanade.tachiyomi.util.storage.DiskUtil
 import eu.kanade.tachiyomi.util.storage.getUriCompat
 import eu.kanade.tachiyomi.util.system.notificationManager
 import eu.kanade.tachiyomi.util.system.toast
+import exh.md.similar.SimilarUpdateService
 import uy.kohesive.injekt.Injekt
 import uy.kohesive.injekt.api.get
 import uy.kohesive.injekt.injectLazy
@@ -100,6 +101,9 @@ class NotificationReceiver : BroadcastReceiver() {
                     markAsRead(urls, mangaId)
                 }
             }
+            // SY -->
+            ACTION_CANCEL_SIMILAR_UPDATE -> cancelSimilarUpdate(context)
+            // SY <--
         }
     }
 
@@ -241,6 +245,18 @@ class NotificationReceiver : BroadcastReceiver() {
         }
     }
 
+    // SY -->
+    /**
+     * Method called when user wants to stop a similar manga update
+     *
+     * @param context context of application
+     */
+    private fun cancelSimilarUpdate(context: Context) {
+        SimilarUpdateService.stop(context)
+        Handler().post { dismissNotification(context, Notifications.ID_SIMILAR_PROGRESS) }
+    }
+    // SY <--
+
     companion object {
         private const val NAME = "NotificationReceiver"
 
@@ -298,6 +314,11 @@ class NotificationReceiver : BroadcastReceiver() {
         // Value containing chapter url.
         private const val EXTRA_CHAPTER_URL = "$ID.$NAME.EXTRA_CHAPTER_URL"
 
+        // Sy -->
+        // Called to cancel similar manga update.
+        private const val ACTION_CANCEL_SIMILAR_UPDATE = "$ID.$NAME.CANCEL_SIMILAR_UPDATE"
+        // SY <--
+
         /**
          * Returns a [PendingIntent] that resumes the download of a chapter
          *
@@ -548,5 +569,20 @@ class NotificationReceiver : BroadcastReceiver() {
             }
             return PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
         }
+
+        // SY -->
+        /**
+         * Returns [PendingIntent] that starts a service which stops the similar update
+         *
+         * @param context context of application
+         * @return [PendingIntent]
+         */
+        internal fun cancelSimilarUpdatePendingBroadcast(context: Context): PendingIntent {
+            val intent = Intent(context, NotificationReceiver::class.java).apply {
+                action = ACTION_CANCEL_SIMILAR_UPDATE
+            }
+            return PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT)
+        }
+        // SY <--
     }
 }

app/src/main/java/eu/kanade/tachiyomi/data/notification/Notifications.kt

@@ -62,6 +62,15 @@ object Notifications {
     const val ID_BACKUP_COMPLETE = -502
     const val ID_RESTORE_COMPLETE = -504
 
+    // SY -->
+    /**
+     * Notification channel and ids used for backup and restore.
+     */
+    const val CHANNEL_SIMILAR = "similar_channel"
+    const val ID_SIMILAR_PROGRESS = -601
+    const val ID_SIMILAR_COMPLETE = -602
+    // SY <--
+
     private val deprecatedChannels = listOf(
         "downloader_channel",
         "backup_restore_complete_channel"
@@ -143,6 +152,13 @@ object Notifications {
                 group = GROUP_BACKUP_RESTORE
                 setShowBadge(false)
                 setSound(null, null)
+            },
+            NotificationChannel(
+                CHANNEL_SIMILAR,
+                context.getString(R.string.similar),
+                NotificationManager.IMPORTANCE_LOW
+            ).apply {
+                setShowBadge(false)
             }
         ).forEach(context.notificationManager::createNotificationChannel)
 

app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferenceKeys.kt

@@ -309,6 +309,12 @@ object PreferenceKeys {
 
     const val mangaDexForceLatestCovers = "manga_dex_force_latest_covers"
 
+    const val mangadexSimilarEnabled = "pref_related_show_tab_key"
+
+    const val mangadexSimilarUpdateInterval = "related_update_interval"
+
+    const val mangadexSimilarOnlyOverWifi = "pref_simular_only_over_wifi_key"
+
     const val preferredMangaDexId = "preferred_mangaDex_id"
 
     const val dataSaver = "data_saver"

app/src/main/java/eu/kanade/tachiyomi/data/preference/PreferencesHelper.kt

@@ -431,6 +431,14 @@ class PreferencesHelper(val context: Context) {
 
     fun preferredMangaDexId() = flowPrefs.getString(Keys.preferredMangaDexId, "0")
 
+    fun mangadexSimilarEnabled() = flowPrefs.getBoolean(Keys.mangadexSimilarEnabled, false)
+
+    fun shownMangaDexSimilarAskDialog() = flowPrefs.getBoolean("shown_similar_ask_dialog", false)
+
+    fun mangadexSimilarOnlyOverWifi() = flowPrefs.getBoolean(Keys.mangadexSimilarOnlyOverWifi, true)
+
+    fun mangadexSimilarUpdateInterval() = flowPrefs.getInt(Keys.mangadexSimilarUpdateInterval, 2)
+
     fun dataSaver() = flowPrefs.getBoolean(Keys.dataSaver, false)
 
     fun ignoreJpeg() = flowPrefs.getBoolean(Keys.ignoreJpeg, false)

app/src/main/java/eu/kanade/tachiyomi/source/online/all/MangaDex.kt

@@ -6,6 +6,7 @@ import android.content.SharedPreferences
 import android.net.Uri
 import androidx.core.text.HtmlCompat
 import com.bluelinelabs.conductor.Controller
+import eu.kanade.tachiyomi.data.database.models.Manga
 import eu.kanade.tachiyomi.data.database.models.Track
 import eu.kanade.tachiyomi.data.preference.PreferencesHelper
 import eu.kanade.tachiyomi.data.track.TrackManager
@@ -35,6 +36,7 @@ import exh.md.handlers.ApiMangaParser
 import exh.md.handlers.FollowsHandler
 import exh.md.handlers.MangaHandler
 import exh.md.handlers.MangaPlusHandler
+import exh.md.handlers.SimilarHandler
 import exh.md.utils.FollowStatus
 import exh.md.utils.MdLang
 import exh.md.utils.MdUtil
@@ -257,6 +259,10 @@ class MangaDex(delegate: HttpSource, val context: Context) :
         return MangaHandler(client, headers, listOf(mdLang)).fetchRandomMangaId()
     }
 
+    fun fetchMangaSimilar(manga: Manga): Observable<MangasPage> {
+        return SimilarHandler(preferences, useLowQualityThumbnail()).fetchSimilar(manga)
+    }
+
     private fun importIdToMdId(query: String, fail: () -> Observable<MangasPage>): Observable<MangasPage> =
         when {
             query.toIntOrNull() != null -> {

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourceController.kt

@@ -2,7 +2,6 @@ package eu.kanade.tachiyomi.ui.browse.source.browse
 
 import android.content.res.Configuration
 import android.os.Bundle
-import android.os.Parcelable
 import android.view.LayoutInflater
 import android.view.Menu
 import android.view.MenuInflater
@@ -10,7 +9,6 @@ import android.view.MenuItem
 import android.view.View
 import android.view.ViewGroup
 import androidx.appcompat.widget.SearchView
-import androidx.core.os.bundleOf
 import androidx.core.view.isVisible
 import androidx.recyclerview.widget.GridLayoutManager
 import androidx.recyclerview.widget.LinearLayoutManager
@@ -37,6 +35,7 @@ import eu.kanade.tachiyomi.source.LocalSource
 import eu.kanade.tachiyomi.source.model.FilterList
 import eu.kanade.tachiyomi.source.online.HttpSource
 import eu.kanade.tachiyomi.source.online.LoginSource
+import eu.kanade.tachiyomi.source.online.all.MangaDex
 import eu.kanade.tachiyomi.ui.base.controller.FabController
 import eu.kanade.tachiyomi.ui.base.controller.NucleusController
 import eu.kanade.tachiyomi.ui.base.controller.withFadeTransaction
@@ -55,9 +54,9 @@ import eu.kanade.tachiyomi.util.view.snack
 import eu.kanade.tachiyomi.widget.AutofitRecyclerView
 import eu.kanade.tachiyomi.widget.EmptyView
 import exh.isEhBasedSource
+import exh.md.similar.ui.EnableMangaDexSimilarDialogController
 import exh.savedsearches.EXHSavedSearch
 import exh.source.EnhancedHttpSource.Companion.getMainSource
-import kotlinx.android.parcel.Parcelize
 import kotlinx.android.synthetic.main.main_activity.root_coordinator
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.flow.drop
@@ -109,17 +108,10 @@ open class BrowseSourceController(bundle: Bundle) :
 
     private val preferences: PreferencesHelper by injectLazy()
 
-    // SY -->
-    private val recommendsConfig: RecommendsConfig? = args.getParcelable(RECOMMENDS_CONFIG)
-    // SY <--
-
-    // AZ -->
-    private val mode = if (recommendsConfig == null) Mode.CATALOGUE else Mode.RECOMMENDS
-    // AZ <--
     /**
      * Adapter containing the list of manga from the catalogue.
      */
-    private var adapter: FlexibleAdapter<IFlexible<*>>? = null
+    /* SY --> */ protected /* SY <-- */ var adapter: FlexibleAdapter<IFlexible<*>>? = null
 
     private var actionFab: ExtendedFloatingActionButton? = null
     private var actionFabScrollListener: RecyclerView.OnScrollListener? = null
@@ -154,12 +146,7 @@ open class BrowseSourceController(bundle: Bundle) :
     }
 
     override fun getTitle(): String? {
-        // SY -->
+        return presenter.source.name
-        return when (mode) {
-            Mode.CATALOGUE -> presenter.source.name
-            Mode.RECOMMENDS -> recommendsConfig!!.title
-        }
-        // SY <--
     }
 
     override fun createPresenter(): BrowseSourcePresenter {
@@ -167,7 +154,6 @@ open class BrowseSourceController(bundle: Bundle) :
         return BrowseSourcePresenter(
             args.getLong(SOURCE_ID_KEY),
             args.getString(SEARCH_QUERY_KEY),
-            recommendsMangaId = if (mode == Mode.RECOMMENDS) recommendsConfig?.mangaId else null,
             filters = args.getString(FILTERS_CONFIG_KEY)
         )
         // SY <--
@@ -192,6 +178,11 @@ open class BrowseSourceController(bundle: Bundle) :
 
         // SY -->
         val mainSource = presenter.source.getMainSource()
+        if (mainSource is MangaDex && !preferences.mangadexSimilarEnabled().get() && !preferences.shownMangaDexSimilarAskDialog().get()) {
+            EnableMangaDexSimilarDialogController().showDialog(router)
+            preferences.shownMangaDexSimilarAskDialog().set(true)
+        }
+
         if (mainSource is LoginSource && mainSource.needsLogin && !mainSource.isLogged()) {
             val dialog = mainSource.getLoginDialog(mainSource, activity!!)
             dialog.showDialog(router)
@@ -200,12 +191,6 @@ open class BrowseSourceController(bundle: Bundle) :
     }
 
     open fun initFilterSheet() {
-        // SY -->
-        if (mode == Mode.RECOMMENDS) {
-            return
-        }
-        // SY <--
-
         if (presenter.sourceFilters.isEmpty()) {
             // SY -->
             actionFab?.text = activity!!.getString(R.string.saved_searches)
@@ -455,10 +440,6 @@ open class BrowseSourceController(bundle: Bundle) :
         }
         menu.findItem(displayItem).isChecked = true
         // SY -->
-        if (mode == Mode.RECOMMENDS) {
-            menu.findItem(R.id.action_search).isVisible = false
-        }
-
         if (preferences.enhancedEHentaiView().get() && presenter.source.isEhBasedSource()) {
             menu.findItem(R.id.action_display_mode).isVisible = false
         }
@@ -472,9 +453,9 @@ open class BrowseSourceController(bundle: Bundle) :
         menu.findItem(R.id.action_open_in_web_view).isVisible = isHttpSource
 
         val isLocalSource = presenter.source is LocalSource
-        // SY -->
+        menu.findItem(R.id.action_local_source_help).isVisible = isLocalSource
-        menu.findItem(R.id.action_local_source_help).isVisible = isLocalSource && mode == Mode.CATALOGUE
 
+        // SY -->
         menu.findItem(R.id.action_settings).isVisible = presenter.source is ConfigurableSource
         // SY <--
     }
@@ -555,19 +536,14 @@ open class BrowseSourceController(bundle: Bundle) :
      *
      * @param error the error received.
      */
-    fun onAddPageError(error: Throwable) {
+    /* SY --> */ open /* SY <-- */fun onAddPageError(error: Throwable) {
         // SY -->
         XLog.w("> Failed to load next catalogue page!", error)
-
+        XLog.w(
-        if (mode == Mode.CATALOGUE) {
+            "> (source.id: %s, source.name: %s)",
-            XLog.w(
+            presenter.source.id,
-                "> (source.id: %s, source.name: %s)",
+            presenter.source.name
-                presenter.source.id,
+        )
-                presenter.source.name
-            )
-        } else {
-            XLog.w("> Recommendations")
-        }
         // SY <--
 
         val adapter = adapter ?: return
@@ -590,7 +566,7 @@ open class BrowseSourceController(bundle: Bundle) :
         if (adapter.isEmpty) {
             val actions = emptyList<EmptyView.Action>().toMutableList()
 
-            if (presenter.source is LocalSource /* SY --> */ && mode == Mode.CATALOGUE /* SY <-- */) {
+            if (presenter.source is LocalSource) {
                 actions += EmptyView.Action(R.string.local_source_help_guide, View.OnClickListener { openLocalSourceHelpGuide() })
             } else {
                 actions += EmptyView.Action(R.string.action_retry, retryAction)
@@ -734,36 +710,16 @@ open class BrowseSourceController(bundle: Bundle) :
      */
     override fun onItemClick(view: View, position: Int): Boolean {
         val item = adapter?.getItem(position) as? SourceItem ?: return false
-        // SY -->
+        router.pushController(
-        when (mode) {
+            MangaController(
-            Mode.CATALOGUE -> {
+                item.manga,
-                router.pushController(
+                true,
-                    MangaController(
+                args.getParcelable(MangaController.SMART_SEARCH_CONFIG_EXTRA)
-                        item.manga,
+            ).withFadeTransaction()
-                        true,
+        )
-                        args.getParcelable(MangaController.SMART_SEARCH_CONFIG_EXTRA)
-                    ).withFadeTransaction()
-                )
-            }
-            Mode.RECOMMENDS -> openSmartSearch(item.manga.originalTitle)
-        }
-        // SY <--
         return false
     }
 
-    // AZ -->
-    private fun openSmartSearch(title: String) {
-        val smartSearchConfig = SourceController.SmartSearchConfig(title)
-        router.pushController(
-            SourceController(
-                bundleOf(
-                    SourceController.SMART_SEARCH_CONFIG to smartSearchConfig
-                )
-            ).withFadeTransaction()
-        )
-    }
-
-    // AZ <--
     /**
      * Called when a manga is long clicked.
      *
@@ -774,9 +730,6 @@ open class BrowseSourceController(bundle: Bundle) :
      * @param position the position of the element clicked.
      */
     override fun onItemLongClick(position: Int) {
-        // SY -->
-        if (mode == Mode.RECOMMENDS) return
-        // SY <--
         val activity = activity ?: return
         val manga = (adapter?.getItem(position) as? SourceItem?)?.manga ?: return
 
@@ -852,16 +805,6 @@ open class BrowseSourceController(bundle: Bundle) :
         activity?.toast(activity?.getString(R.string.manga_added_library))
     }
 
-    // SY -->
-    @Parcelize
-    data class RecommendsConfig(val title: String, val mangaId: Long?) : Parcelable
-
-    enum class Mode {
-        CATALOGUE,
-        RECOMMENDS
-    }
-    // SY <--
-
     companion object {
         const val SOURCE_ID_KEY = "sourceId"
         const val SEARCH_QUERY_KEY = "searchQuery"
@@ -869,7 +812,6 @@ open class BrowseSourceController(bundle: Bundle) :
         // SY -->
         const val SMART_SEARCH_CONFIG_KEY = "smartSearchConfig"
         const val FILTERS_CONFIG_KEY = "filters"
-        const val RECOMMENDS_CONFIG = "RECOMMENDS_CONFIG"
         // SY <--
     }
 }

app/src/main/java/eu/kanade/tachiyomi/ui/browse/source/browse/BrowseSourcePresenter.kt

@@ -59,7 +59,6 @@ open class BrowseSourcePresenter(
     private val sourceId: Long,
     private val searchQuery: String? = null,
     // SY -->
-    private val recommendsMangaId: Long? = null,
     private val filters: String? = null,
     // SY <--
     private val sourceManager: SourceManager = Injekt.get(),
@@ -145,10 +144,6 @@ open class BrowseSourcePresenter(
             query = savedState.getString(::query.name, "")
         }
 
-        if (recommendsMangaId != null) {
-            manga = db.getManga(recommendsMangaId).executeAsBlocking()
-        }
-
         restartPager(/* SY -->*/ filters = if (allDefault) this.appliedFilters else sourceFilters /* SY <--*/)
     }
 
@@ -170,11 +165,7 @@ open class BrowseSourcePresenter(
         subscribeToMangaInitializer()
 
         // Create a new pager.
-        // SY -->
+        pager = createPager(query, filters)
-        pager = if (recommendsMangaId != null) RecommendsPager(
-            manga ?: throw Exception("Could not get Manga")
-        ) else createPager(query, filters)
-        // SY <--
 
         val sourceId = source.id
 

app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaController.kt

@@ -31,6 +31,8 @@ import androidx.core.view.isVisible
 import androidx.recyclerview.widget.ConcatAdapter
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
+import com.afollestad.materialdialogs.MaterialDialog
+import com.afollestad.materialdialogs.list.listItemsSingleChoice
 import com.bluelinelabs.conductor.ControllerChangeHandler
 import com.bluelinelabs.conductor.ControllerChangeType
 import com.bumptech.glide.load.engine.DiskCacheStrategy
@@ -50,11 +52,13 @@ import eu.kanade.tachiyomi.data.glide.GlideApp
 import eu.kanade.tachiyomi.data.glide.toMangaThumbnail
 import eu.kanade.tachiyomi.data.preference.PreferencesHelper
 import eu.kanade.tachiyomi.databinding.MangaControllerBinding
+import eu.kanade.tachiyomi.source.CatalogueSource
 import eu.kanade.tachiyomi.source.LocalSource
 import eu.kanade.tachiyomi.source.Source
 import eu.kanade.tachiyomi.source.SourceManager
 import eu.kanade.tachiyomi.source.online.HttpSource
 import eu.kanade.tachiyomi.source.online.MetadataSource
+import eu.kanade.tachiyomi.source.online.all.MangaDex
 import eu.kanade.tachiyomi.ui.base.controller.FabController
 import eu.kanade.tachiyomi.ui.base.controller.NucleusController
 import eu.kanade.tachiyomi.ui.base.controller.ToolbarLiftOnScrollController
@@ -96,7 +100,9 @@ import eu.kanade.tachiyomi.util.view.shrinkOnScroll
 import eu.kanade.tachiyomi.util.view.snack
 import exh.MERGED_SOURCE_ID
 import exh.isEhBasedSource
+import exh.md.similar.ui.MangaDexSimilarController
 import exh.metadata.metadata.base.FlatMetadata
+import exh.recs.RecommendsController
 import exh.source.EnhancedHttpSource.Companion.getMainSource
 import kotlinx.android.synthetic.main.main_activity.root_coordinator
 import kotlinx.android.synthetic.main.main_activity.toolbar
@@ -748,15 +754,25 @@ class MangaController :
 
     // AZ -->
     fun openRecommends() {
-        val recommendsConfig = BrowseSourceController.RecommendsConfig(presenter.manga.originalTitle, presenter.manga.id)
+        val source = presenter.source.getMainSource()
-
+        if (source is MangaDex && preferences.mangadexSimilarEnabled().get()) {
-        router?.pushController(
+            MaterialDialog(activity!!)
-            BrowseSourceController(
+                .title(R.string.az_recommends)
-                bundleOf(
+                .listItemsSingleChoice(
-                    BrowseSourceController.RECOMMENDS_CONFIG to recommendsConfig
+                    items = listOf(
-                )
+                        "MangaDex similar",
-            ).withFadeTransaction()
+                        "Community recommendations"
-        )
+                    )
+                ) { _, index, _ ->
+                    when (index) {
+                        0 -> router.pushController(MangaDexSimilarController(presenter.manga, source).withFadeTransaction())
+                        1 -> router.pushController(RecommendsController(presenter.manga, source).withFadeTransaction())
+                    }
+                }
+                .show()
+        } else if (source is CatalogueSource) {
+            router.pushController(RecommendsController(presenter.manga, source).withFadeTransaction())
+        }
     }
     // AZ <--
 

app/src/main/java/eu/kanade/tachiyomi/ui/setting/SettingsMainController.kt

@@ -90,7 +90,7 @@ class SettingsMainController : SettingsController() {
             preference {
                 iconRes = R.drawable.ic_tracker_mangadex_logo_24dp
                 iconTint = tintColor
-                titleRes = R.string.mangadex_specific_settings
+                titleRes = R.string.pref_category_mangadex
                 onClick { navigateTo(SettingsMangaDexController()) }
             }
         }

app/src/main/java/eu/kanade/tachiyomi/ui/setting/SettingsMangaDexController.kt

@@ -1,17 +1,25 @@
 package eu.kanade.tachiyomi.ui.setting
 
+import android.content.Intent
+import androidx.core.net.toUri
 import androidx.preference.PreferenceScreen
 import eu.kanade.tachiyomi.R
 import eu.kanade.tachiyomi.data.library.LibraryUpdateService
 import eu.kanade.tachiyomi.data.preference.PreferenceKeys
 import eu.kanade.tachiyomi.source.Source
 import eu.kanade.tachiyomi.util.preference.defaultValue
+import eu.kanade.tachiyomi.util.preference.entriesRes
+import eu.kanade.tachiyomi.util.preference.intListPreference
 import eu.kanade.tachiyomi.util.preference.listPreference
+import eu.kanade.tachiyomi.util.preference.onChange
 import eu.kanade.tachiyomi.util.preference.onClick
 import eu.kanade.tachiyomi.util.preference.preference
+import eu.kanade.tachiyomi.util.preference.preferenceCategory
 import eu.kanade.tachiyomi.util.preference.summaryRes
 import eu.kanade.tachiyomi.util.preference.switchPreference
 import eu.kanade.tachiyomi.util.preference.titleRes
+import eu.kanade.tachiyomi.util.system.toast
+import exh.md.similar.SimilarUpdateJob
 import exh.md.utils.MdUtil
 import exh.widget.preference.MangaDexLoginPreference
 import exh.widget.preference.MangadexLoginDialog
@@ -85,6 +93,76 @@ class SettingsMangaDexController :
                 )
             }
         }
+
+        preferenceCategory {
+            titleRes = R.string.similar_settings
+
+            preference {
+                key = "pref_similar_screen"
+                titleRes = R.string.similar_screen
+                summaryRes = R.string.similar_screen_summary_message
+                isIconSpaceReserved = true
+            }
+
+            switchPreference {
+                key = PreferenceKeys.mangadexSimilarEnabled
+                titleRes = R.string.similar_screen
+                defaultValue = false
+                onClick {
+                    SimilarUpdateJob.setupTask(context)
+                }
+            }
+
+            switchPreference {
+                key = PreferenceKeys.mangadexSimilarOnlyOverWifi
+                titleRes = R.string.pref_download_only_over_wifi
+                defaultValue = true
+                onClick {
+                    SimilarUpdateJob.setupTask(context, true)
+                }
+            }
+
+            preference {
+                key = "pref_similar_manually_update"
+                titleRes = R.string.similar_manually_update
+                summaryRes = R.string.similar_manually_update_message
+                onClick {
+                    SimilarUpdateJob.doWorkNow(context)
+                    context.toast(R.string.similar_manually_toast)
+                }
+            }
+
+            intListPreference {
+                key = PreferenceKeys.mangadexSimilarUpdateInterval
+                titleRes = R.string.similar_update_fequency
+                entriesRes = arrayOf(
+                    R.string.update_never,
+                    R.string.update_24hour,
+                    R.string.update_48hour,
+                    R.string.update_weekly,
+                    R.string.update_monthly
+                )
+                entryValues = arrayOf("0", "1", "2", "7", "30")
+                defaultValue = "2"
+
+                onChange {
+                    SimilarUpdateJob.setupTask(context, true)
+                    true
+                }
+            }
+
+            preference {
+                key = "similar_credits"
+                title = "Credits"
+                val url = "https://github.com/goldbattle/MangadexRecomendations"
+                summary = context.getString(R.string.similar_credit_message, url)
+                onClick {
+                    val intent = Intent(Intent.ACTION_VIEW, url.toUri())
+                    startActivity(intent)
+                }
+                isIconSpaceReserved = true
+            }
+        }
     }
 
     override fun siteLoginDialogClosed(source: Source) {

app/src/main/java/exh/md/follows/MangaDexFollowsPresenter.kt

@@ -4,7 +4,7 @@ import eu.kanade.tachiyomi.source.model.FilterList
 import eu.kanade.tachiyomi.source.online.all.MangaDex
 import eu.kanade.tachiyomi.ui.browse.source.browse.BrowseSourcePresenter
 import eu.kanade.tachiyomi.ui.browse.source.browse.Pager
-import exh.source.EnhancedHttpSource
+import exh.source.EnhancedHttpSource.Companion.getMainSource
 
 /**
  * Presenter of [MangaDexFollowsController]. Inherit BrowseCataloguePresenter.
@@ -12,7 +12,7 @@ import exh.source.EnhancedHttpSource
 class MangaDexFollowsPresenter(sourceId: Long) : BrowseSourcePresenter(sourceId) {
 
     override fun createPager(query: String, filters: FilterList): Pager {
-        val sourceAsMangaDex = (source as EnhancedHttpSource).enhancedSource as MangaDex
+        val sourceAsMangaDex = source.getMainSource() as MangaDex
         return MangaDexFollowsPager(sourceAsMangaDex)
     }
 }

app/src/main/java/exh/md/handlers/SimilarHandler.kt

@@ -1,47 +1,41 @@
 package exh.md.handlers
 
-// todo make this work
+import eu.kanade.tachiyomi.data.database.DatabaseHelper
-/*import eu.kanade.tachiyomi.data.database.DatabaseHelper
 import eu.kanade.tachiyomi.data.database.models.Manga
-import eu.kanade.tachiyomi.data.database.models.MangaSimilarImpl
 import eu.kanade.tachiyomi.data.preference.PreferencesHelper
 import eu.kanade.tachiyomi.source.model.MangasPage
 import eu.kanade.tachiyomi.source.model.SManga
+import exh.md.similar.sql.models.MangaSimilar
+import exh.md.similar.sql.models.MangaSimilarImpl
 import exh.md.utils.MdUtil
 import rx.Observable
 import uy.kohesive.injekt.Injekt
 import uy.kohesive.injekt.api.get
 
-class SimilarHandler(val preferences: PreferencesHelper) {
+class SimilarHandler(val preferences: PreferencesHelper, private val useLowQualityCovers: Boolean) {
 
-    *//**
+    /*
- * fetch our similar mangas
+     * fetch our similar mangas
- *//*
+     */
     fun fetchSimilar(manga: Manga): Observable<MangasPage> {
-
         // Parse the Mangadex id from the URL
-        val mangaid = MdUtil.getMangaId(manga.url).toLong()
+        return Observable.just(MdUtil.getMangaId(manga.url).toLong())
-
+            .flatMap { mangaId ->
-        val lowQualityCovers = preferences.mangaDexLowQualityCovers().get()
+                val db = Injekt.get<DatabaseHelper>()
-
+                db.getSimilar(mangaId).asRxObservable()
-        // Get our current database
+            }.map { similarMangaDb: MangaSimilar? ->
-        val db = Injekt.get<DatabaseHelper>()
+                similarMangaDb?.let { mangaSimilar ->
-        val similarMangaDb = db.getSimilar(mangaid).executeAsBlocking() ?: return Observable.just(MangasPage(mutableListOf(), false))
+                    val similarMangaTitles = mangaSimilar.matched_titles.split(MangaSimilarImpl.DELIMITER)
-
+                    val similarMangaIds = mangaSimilar.matched_ids.split(MangaSimilarImpl.DELIMITER)
-        // Check if we have a result
+                    val similarMangas = similarMangaIds.mapIndexed { index, similarId ->
-
+                        SManga.create().apply {
-        val similarMangaTitles = similarMangaDb.matched_titles.split(MangaSimilarImpl.DELIMITER)
+                            title = similarMangaTitles[index]
-        val similarMangaIds = similarMangaDb.matched_ids.split(MangaSimilarImpl.DELIMITER)
+                            url = "/manga/$similarId/"
-
+                            thumbnail_url = MdUtil.formThumbUrl(url, useLowQualityCovers)
-        val similarMangas = similarMangaIds.mapIndexed { index, similarId ->
+                        }
-            SManga.create().apply {
+                    }
-                title = similarMangaTitles[index]
+                    MangasPage(similarMangas, false)
-                url = "/manga/$similarId/"
+                } ?: MangasPage(mutableListOf(), false)
-                thumbnail_url = MdUtil.formThumbUrl(url, lowQualityCovers)
             }
-        }
-
-        // Return the matches
-        return Observable.just(MangasPage(similarMangas, false))
     }
-}*/
+}

app/src/main/java/exh/md/similar/SimilarHttpService.kt

@@ -0,0 +1,47 @@
+package exh.md.similar
+
+import com.jakewharton.retrofit2.converter.kotlinx.serialization.asConverterFactory
+import eu.kanade.tachiyomi.network.NetworkHelper
+import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.json.Json
+import okhttp3.MediaType.Companion.toMediaType
+import okhttp3.ResponseBody
+import retrofit2.Call
+import retrofit2.Retrofit
+import retrofit2.http.GET
+import retrofit2.http.Streaming
+import uy.kohesive.injekt.injectLazy
+
+interface SimilarHttpService {
+    companion object {
+        private val client by lazy {
+            val network: NetworkHelper by injectLazy()
+            network.client.newBuilder()
+                // unzip interceptor which will add the correct headers
+                .addNetworkInterceptor { chain ->
+                    val originalResponse = chain.proceed(chain.request())
+                    originalResponse.newBuilder()
+                        .header("Content-Encoding", "gzip")
+                        .header("Content-Type", "application/json")
+                        .build()
+                }
+                .build()
+        }
+
+        @ExperimentalSerializationApi
+        fun create(): SimilarHttpService {
+            // actual builder, which will parse the underlying json file
+            val adapter = Retrofit.Builder()
+                .baseUrl("https://raw.githubusercontent.com")
+                .addConverterFactory(Json.asConverterFactory("application/json".toMediaType()))
+                .client(client)
+                .build()
+
+            return adapter.create(SimilarHttpService::class.java)
+        }
+    }
+
+    @Streaming
+    @GET("/goldbattle/MangadexRecomendations/master/output/mangas_compressed.json.gz")
+    fun getSimilarResults(): Call<ResponseBody>
+}

app/src/main/java/exh/md/similar/SimilarUpdateJob.kt

@@ -0,0 +1,74 @@
+package exh.md.similar
+
+import android.content.Context
+import androidx.work.Constraints
+import androidx.work.ExistingPeriodicWorkPolicy
+import androidx.work.NetworkType
+import androidx.work.OneTimeWorkRequestBuilder
+import androidx.work.PeriodicWorkRequestBuilder
+import androidx.work.WorkManager
+import androidx.work.Worker
+import androidx.work.WorkerParameters
+import eu.kanade.tachiyomi.data.preference.PreferencesHelper
+import uy.kohesive.injekt.Injekt
+import uy.kohesive.injekt.api.get
+import java.util.concurrent.TimeUnit
+
+class SimilarUpdateJob(private val context: Context, workerParams: WorkerParameters) :
+    Worker(context, workerParams) {
+
+    override fun doWork(): Result {
+        SimilarUpdateService.start(context)
+        return Result.success()
+    }
+
+    companion object {
+        const val TAG = "RelatedUpdate"
+
+        fun setupTask(context: Context, skipInitial: Boolean = false) {
+            val preferences = Injekt.get<PreferencesHelper>()
+            val enabled = preferences.mangadexSimilarEnabled().get()
+            val interval = preferences.mangadexSimilarUpdateInterval().get()
+            if (enabled) {
+                // We are enabled, so construct the constraints
+                val wifiRestriction = if (preferences.mangadexSimilarOnlyOverWifi().get()) {
+                    NetworkType.UNMETERED
+                } else {
+                    NetworkType.CONNECTED
+                }
+                val constraints = Constraints.Builder()
+                    .setRequiredNetworkType(wifiRestriction)
+                    .build()
+
+                // If we are not skipping the initial then run it right now
+                // Note that we won't run it if the constraints are not satisfied
+                if (!skipInitial) {
+                    WorkManager.getInstance(context).enqueue(OneTimeWorkRequestBuilder<SimilarUpdateJob>().setConstraints(constraints).build())
+                }
+
+                // Finally build the periodic request
+                val request = PeriodicWorkRequestBuilder<SimilarUpdateJob>(
+                    interval.toLong(),
+                    TimeUnit.DAYS,
+                    1,
+                    TimeUnit.HOURS
+                )
+                    .addTag(TAG)
+                    .setConstraints(constraints)
+                    .build()
+
+                if (interval > 0) {
+                    WorkManager.getInstance(context).enqueueUniquePeriodicWork(TAG, ExistingPeriodicWorkPolicy.REPLACE, request)
+                } else {
+                    WorkManager.getInstance(context).cancelAllWorkByTag(TAG)
+                }
+            } else {
+                WorkManager.getInstance(context).cancelAllWorkByTag(TAG)
+            }
+        }
+
+        fun doWorkNow(context: Context) {
+            WorkManager.getInstance(context).enqueue(OneTimeWorkRequestBuilder<SimilarUpdateJob>().build())
+        }
+    }
+}

app/src/main/java/exh/md/similar/SimilarUpdateService.kt

@@ -0,0 +1,324 @@
+package exh.md.similar
+
+import android.app.Service
+import android.content.Context
+import android.content.Intent
+import android.graphics.BitmapFactory
+import android.os.PowerManager
+import androidx.core.app.NotificationCompat
+import androidx.core.app.NotificationManagerCompat
+import androidx.core.content.ContextCompat
+import androidx.core.text.isDigitsOnly
+import com.elvishew.xlog.XLog
+import com.squareup.moshi.JsonReader
+import eu.kanade.tachiyomi.R
+import eu.kanade.tachiyomi.data.database.DatabaseHelper
+import eu.kanade.tachiyomi.data.notification.NotificationReceiver
+import eu.kanade.tachiyomi.data.notification.Notifications
+import eu.kanade.tachiyomi.util.system.isServiceRunning
+import eu.kanade.tachiyomi.util.system.notificationManager
+import exh.md.similar.sql.models.MangaSimilarImpl
+import kotlinx.coroutines.CoroutineExceptionHandler
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.isActive
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+import okio.buffer
+import okio.sink
+import okio.source
+import retrofit2.awaitResponse
+import uy.kohesive.injekt.Injekt
+import uy.kohesive.injekt.api.get
+import java.io.File
+import java.util.concurrent.TimeUnit
+
+class SimilarUpdateService(
+    val db: DatabaseHelper = Injekt.get()
+) : Service() {
+
+    /**
+     * Wake lock that will be held until the service is destroyed.
+     */
+    private lateinit var wakeLock: PowerManager.WakeLock
+
+    var similarServiceScope = CoroutineScope(Dispatchers.IO + Job())
+
+    /**
+     * Subscription where the update is done.
+     */
+    private var job: Job? = null
+
+    /**
+     * Pending intent of action that cancels the library update
+     */
+    private val cancelIntent by lazy {
+        NotificationReceiver.cancelSimilarUpdatePendingBroadcast(this)
+    }
+
+    private val progressNotification by lazy {
+        NotificationCompat.Builder(this, Notifications.CHANNEL_SIMILAR)
+            .setLargeIcon(BitmapFactory.decodeResource(this.resources, R.mipmap.ic_launcher))
+            .setSmallIcon(R.drawable.ic_tachi)
+            .setOngoing(true)
+            .setContentTitle(getString(R.string.similar_loading_progress_start))
+            .setAutoCancel(true)
+            .addAction(
+                R.drawable.ic_close_24dp,
+                getString(android.R.string.cancel),
+                cancelIntent
+            )
+    }
+
+    /**
+     * Method called when the service is created. It injects dagger dependencies and acquire
+     * the wake lock.
+     */
+    override fun onCreate() {
+        super.onCreate()
+        startForeground(Notifications.ID_SIMILAR_PROGRESS, progressNotification.build())
+        wakeLock = (getSystemService(Context.POWER_SERVICE) as PowerManager).newWakeLock(
+            PowerManager.PARTIAL_WAKE_LOCK,
+            "SimilarUpdateService:WakeLock"
+        )
+        wakeLock.acquire(TimeUnit.MINUTES.toMillis(30))
+    }
+
+    /**
+     * Method called when the service is destroyed. It destroys subscriptions and releases the wake
+     * lock.
+     */
+    override fun onDestroy() {
+        job?.cancel()
+        similarServiceScope.cancel()
+        if (wakeLock.isHeld) {
+            wakeLock.release()
+        }
+        super.onDestroy()
+    }
+
+    /**
+     * This method needs to be implemented, but it's not used/needed.
+     */
+    override fun onBind(intent: Intent) = null
+
+    /**
+     * Method called when the service receives an intent.
+     *
+     * @param intent the start intent from.
+     * @param flags the flags of the command.
+     * @param startId the start id of this command.
+     * @return the start value of the command.
+     */
+    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
+        if (intent == null) return Service.START_NOT_STICKY
+
+        // Unsubscribe from any previous subscription if needed.
+        job?.cancel()
+        val handler = CoroutineExceptionHandler { _, exception ->
+            XLog.e(exception)
+            stopSelf(startId)
+            showResultNotification(true)
+            cancelProgressNotification()
+        }
+        job = similarServiceScope.launch(handler) {
+            updateSimilar()
+        }
+        job?.invokeOnCompletion { stopSelf(startId) }
+
+        return START_REDELIVER_INTENT
+    }
+
+    /**
+     * Method that updates the similar database for manga
+     */
+    private suspend fun updateSimilar() = withContext(Dispatchers.IO) {
+        val response = SimilarHttpService.create().getSimilarResults().awaitResponse()
+        if (!response.isSuccessful) {
+            throw Exception("Error trying to download similar file")
+        }
+        val destinationFile = File(filesDir, "neko-similar.json")
+        val buffer = withContext(Dispatchers.IO) { destinationFile.sink().buffer() }
+
+        // write json to file
+        response.body()?.byteStream()?.source()?.use { input ->
+            buffer.use { output ->
+                output.writeAll(input)
+            }
+        }
+
+        val listSimilar = getSimilar(destinationFile)
+
+        // Delete the old similar table
+        db.deleteAllSimilar().executeAsBlocking()
+
+        val totalManga = listSimilar.size
+
+        // Loop through each and insert into the database
+
+        val dataToInsert = listSimilar.mapIndexed { index, similarFromJson ->
+            showProgressNotification(index, totalManga)
+
+            if (similarFromJson.similarIds.size != similarFromJson.similarTitles.size) {
+                return@mapIndexed null
+            }
+
+            val similar = MangaSimilarImpl()
+            similar.id = index.toLong()
+            similar.manga_id = similarFromJson.id.toLong()
+            similar.matched_ids = similarFromJson.similarIds.joinToString(MangaSimilarImpl.DELIMITER)
+            similar.matched_titles = similarFromJson.similarTitles.joinToString(MangaSimilarImpl.DELIMITER)
+            return@mapIndexed similar
+        }.filterNotNull()
+
+        showProgressNotification(dataToInsert.size, totalManga)
+
+        if (dataToInsert.isNotEmpty()) {
+            db.insertSimilar(dataToInsert).executeAsBlocking()
+        }
+        destinationFile.delete()
+        showResultNotification(!this.isActive)
+        cancelProgressNotification()
+    }
+
+    private fun getSimilar(destinationFile: File): List<SimilarFromJson> {
+        val reader = JsonReader.of(destinationFile.source().buffer())
+
+        var processingManga = false
+        var processingTitles = false
+        var mangaId: String? = null
+        var similarIds = mutableListOf<String>()
+        var similarTitles = mutableListOf<String>()
+        val similars = mutableListOf<SimilarFromJson>()
+
+        while (reader.peek() != JsonReader.Token.END_DOCUMENT) {
+            val nextToken = reader.peek()
+
+            if (JsonReader.Token.BEGIN_OBJECT == nextToken) {
+                reader.beginObject()
+            } else if (JsonReader.Token.NAME == nextToken) {
+                val name = reader.nextName()
+                if (!processingManga && name.isDigitsOnly()) {
+                    processingManga = true
+                    // similar add id
+                    mangaId = name
+                } else if (name == "m_titles") {
+                    processingTitles = true
+                }
+            } else if (JsonReader.Token.BEGIN_ARRAY == nextToken) {
+                reader.beginArray()
+            } else if (JsonReader.Token.END_ARRAY == nextToken) {
+                reader.endArray()
+                if (processingTitles) {
+                    processingManga = false
+                    processingTitles = false
+                    similars.add(SimilarFromJson(mangaId!!, similarIds.toList(), similarTitles.toList()))
+                    mangaId = null
+                    similarIds = mutableListOf()
+                    similarTitles = mutableListOf()
+                }
+            } else if (JsonReader.Token.NUMBER == nextToken) {
+                similarIds.add(reader.nextInt().toString())
+            } else if (JsonReader.Token.STRING == nextToken) {
+                if (processingTitles) {
+                    similarTitles.add(reader.nextString())
+                }
+            } else if (JsonReader.Token.END_OBJECT == nextToken) {
+                reader.endObject()
+            }
+        }
+
+        return similars
+    }
+
+    data class SimilarFromJson(val id: String, val similarIds: List<String>, val similarTitles: List<String>)
+
+    /**
+     * Shows the notification containing the currently updating manga and the progress.
+     *
+     * @param current the current progress.
+     * @param total the total progress.
+     */
+    private fun showProgressNotification(current: Int, total: Int) {
+        notificationManager.notify(
+            Notifications.ID_SIMILAR_PROGRESS,
+            progressNotification
+                .setContentTitle(
+                    getString(
+                        R.string.similar_loading_percent,
+                        current,
+                        total
+                    )
+                )
+                .setProgress(total, current, false)
+                .build()
+        )
+    }
+
+    /**
+     * Shows the notification containing the result of the update done by the service.
+     *
+     * @param error if the result was a error.
+     */
+    private fun showResultNotification(error: Boolean = false) {
+        val title = if (error) {
+            getString(R.string.similar_loading_complete_error)
+        } else {
+            getString(
+                R.string.similar_loading_complete
+            )
+        }
+
+        val result = NotificationCompat.Builder(this, Notifications.CHANNEL_SIMILAR)
+            .setContentTitle(title)
+            .setLargeIcon(BitmapFactory.decodeResource(this.resources, R.mipmap.ic_launcher))
+            .setSmallIcon(R.drawable.ic_tachi)
+            .setAutoCancel(true)
+        NotificationManagerCompat.from(this)
+            .notify(Notifications.ID_SIMILAR_COMPLETE, result.build())
+    }
+
+    /**
+     * Cancels the progress notification.
+     */
+    private fun cancelProgressNotification() {
+        notificationManager.cancel(Notifications.ID_SIMILAR_PROGRESS)
+    }
+
+    companion object {
+
+        /**
+         * Returns the status of the service.
+         *
+         * @param context the application context.
+         * @return true if the service is running, false otherwise.
+         */
+        fun isRunning(context: Context): Boolean {
+            return context.isServiceRunning(SimilarUpdateService::class.java)
+        }
+
+        /**
+         * Starts the service. It will be started only if there isn't another instance already
+         * running.
+         *
+         * @param context the application context.
+         */
+        fun start(context: Context) {
+            if (!isRunning(context)) {
+                val intent = Intent(context, SimilarUpdateService::class.java)
+                ContextCompat.startForegroundService(context, intent)
+            }
+        }
+
+        /**
+         * Stops the service.
+         *
+         * @param context the application context.
+         */
+        fun stop(context: Context) {
+            context.stopService(Intent(context, SimilarUpdateService::class.java))
+        }
+    }
+}

app/src/main/java/exh/md/similar/sql/mappers/SimilarTypeMapping.kt

@@ -0,0 +1,63 @@
+package exh.md.similar.sql.mappers
+
+import android.content.ContentValues
+import android.database.Cursor
+import com.pushtorefresh.storio.sqlite.SQLiteTypeMapping
+import com.pushtorefresh.storio.sqlite.operations.delete.DefaultDeleteResolver
+import com.pushtorefresh.storio.sqlite.operations.get.DefaultGetResolver
+import com.pushtorefresh.storio.sqlite.operations.put.DefaultPutResolver
+import com.pushtorefresh.storio.sqlite.queries.DeleteQuery
+import com.pushtorefresh.storio.sqlite.queries.InsertQuery
+import com.pushtorefresh.storio.sqlite.queries.UpdateQuery
+import exh.md.similar.sql.models.MangaSimilar
+import exh.md.similar.sql.models.MangaSimilarImpl
+import exh.md.similar.sql.tables.SimilarTable.COL_ID
+import exh.md.similar.sql.tables.SimilarTable.COL_MANGA_ID
+import exh.md.similar.sql.tables.SimilarTable.COL_MANGA_SIMILAR_MATCHED_IDS
+import exh.md.similar.sql.tables.SimilarTable.COL_MANGA_SIMILAR_MATCHED_TITLES
+import exh.md.similar.sql.tables.SimilarTable.TABLE
+
+class SimilarTypeMapping : SQLiteTypeMapping<MangaSimilar>(
+    SimilarPutResolver(),
+    SimilarGetResolver(),
+    SimilarDeleteResolver()
+)
+
+class SimilarPutResolver : DefaultPutResolver<MangaSimilar>() {
+
+    override fun mapToInsertQuery(obj: MangaSimilar) = InsertQuery.builder()
+        .table(TABLE)
+        .build()
+
+    override fun mapToUpdateQuery(obj: MangaSimilar) = UpdateQuery.builder()
+        .table(TABLE)
+        .where("$COL_ID = ?")
+        .whereArgs(obj.id)
+        .build()
+
+    override fun mapToContentValues(obj: MangaSimilar) = ContentValues(4).apply {
+        put(COL_ID, obj.id)
+        put(COL_MANGA_ID, obj.manga_id)
+        put(COL_MANGA_SIMILAR_MATCHED_IDS, obj.matched_ids)
+        put(COL_MANGA_SIMILAR_MATCHED_TITLES, obj.matched_titles)
+    }
+}
+
+class SimilarGetResolver : DefaultGetResolver<MangaSimilar>() {
+
+    override fun mapFromCursor(cursor: Cursor): MangaSimilar = MangaSimilarImpl().apply {
+        id = cursor.getLong(cursor.getColumnIndex(COL_ID))
+        manga_id = cursor.getLong(cursor.getColumnIndex(COL_MANGA_ID))
+        matched_ids = cursor.getString(cursor.getColumnIndex(COL_MANGA_SIMILAR_MATCHED_IDS))
+        matched_titles = cursor.getString(cursor.getColumnIndex(COL_MANGA_SIMILAR_MATCHED_TITLES))
+    }
+}
+
+class SimilarDeleteResolver : DefaultDeleteResolver<MangaSimilar>() {
+
+    override fun mapToDeleteQuery(obj: MangaSimilar) = DeleteQuery.builder()
+        .table(TABLE)
+        .where("$COL_ID = ?")
+        .whereArgs(obj.id)
+        .build()
+}

app/src/main/java/exh/md/similar/sql/models/MangaSimilar.kt

@@ -0,0 +1,31 @@
+package exh.md.similar.sql.models
+
+import java.io.Serializable
+
+/**
+ * Object containing the history statistics of a chapter
+ */
+interface MangaSimilar : Serializable {
+
+    /**
+     * Id of this similar manga object.
+     */
+    var id: Long?
+
+    /**
+     * Id of matching manga
+     */
+    var manga_id: Long?
+
+    /**
+     * JSONArray.toString() list of ids for this manga
+     * Example: [3467, 5907, 21052, 2141, 6139, 5602, 3999]
+     */
+    var matched_ids: String
+
+    /**
+     * JSONArray.toString() list of titles for this manga
+     * Example: [Title1, Title2, ..., Title10]
+     */
+    var matched_titles: String
+}

app/src/main/java/exh/md/similar/sql/models/MangaSimilarImpl.kt

@@ -0,0 +1,32 @@
+package exh.md.similar.sql.models
+
+class MangaSimilarImpl : MangaSimilar {
+
+    override var id: Long? = null
+
+    override var manga_id: Long? = null
+
+    override lateinit var matched_ids: String
+
+    override lateinit var matched_titles: String
+
+    override fun equals(other: Any?): Boolean {
+        if (this === other) return true
+        if (other == null || javaClass != other.javaClass) return false
+
+        other as MangaSimilar
+
+        if (id != other.id) return false
+        if (manga_id != other.manga_id) return false
+        if (matched_ids != other.matched_ids) return false
+        return matched_titles != other.matched_titles
+    }
+
+    override fun hashCode(): Int {
+        return id.hashCode() + manga_id.hashCode()
+    }
+
+    companion object {
+        const val DELIMITER = "|*|"
+    }
+}

app/src/main/java/exh/md/similar/sql/queries/SimilarQueries.kt

@@ -0,0 +1,42 @@
+package exh.md.similar.sql.queries
+
+import com.pushtorefresh.storio.sqlite.queries.DeleteQuery
+import com.pushtorefresh.storio.sqlite.queries.Query
+import eu.kanade.tachiyomi.data.database.DbProvider
+import exh.md.similar.sql.models.MangaSimilar
+import exh.md.similar.sql.tables.SimilarTable
+
+interface SimilarQueries : DbProvider {
+
+    fun getAllSimilar() = db.get()
+        .listOfObjects(MangaSimilar::class.java)
+        .withQuery(
+            Query.builder()
+                .table(SimilarTable.TABLE)
+                .build()
+        )
+        .prepare()
+
+    fun getSimilar(manga_id: Long) = db.get()
+        .`object`(MangaSimilar::class.java)
+        .withQuery(
+            Query.builder()
+                .table(SimilarTable.TABLE)
+                .where("${SimilarTable.COL_MANGA_ID} = ?")
+                .whereArgs(manga_id)
+                .build()
+        )
+        .prepare()
+
+    fun insertSimilar(similar: MangaSimilar) = db.put().`object`(similar).prepare()
+
+    fun insertSimilar(similarList: List<MangaSimilar>) = db.put().objects(similarList).prepare()
+
+    fun deleteAllSimilar() = db.delete()
+        .byQuery(
+            DeleteQuery.builder()
+                .table(SimilarTable.TABLE)
+                .build()
+        )
+        .prepare()
+}

app/src/main/java/exh/md/similar/sql/tables/SimilarTable.kt

@@ -0,0 +1,27 @@
+package exh.md.similar.sql.tables
+
+object SimilarTable {
+
+    const val TABLE = "manga_related"
+
+    const val COL_ID = "_id"
+
+    const val COL_MANGA_ID = "manga_id"
+
+    const val COL_MANGA_SIMILAR_MATCHED_IDS = "matched_ids"
+
+    const val COL_MANGA_SIMILAR_MATCHED_TITLES = "matched_titles"
+
+    val createTableQuery: String
+        get() =
+            """CREATE TABLE $TABLE(
+            $COL_ID INTEGER NOT NULL PRIMARY KEY,
+            $COL_MANGA_ID INTEGER NOT NULL,
+            $COL_MANGA_SIMILAR_MATCHED_IDS TEXT NOT NULL,
+            $COL_MANGA_SIMILAR_MATCHED_TITLES TEXT NOT NULL,
+            UNIQUE ($COL_ID) ON CONFLICT REPLACE
+            )"""
+
+    val createMangaIdIndexQuery: String
+        get() = "CREATE INDEX ${TABLE}_${COL_MANGA_SIMILAR_MATCHED_IDS}_index ON $TABLE($COL_MANGA_SIMILAR_MATCHED_IDS)"
+}

app/src/main/java/exh/md/similar/ui/EnableMangaDexSimilarDialogController.kt

@@ -0,0 +1,27 @@
+package exh.md.similar.ui
+
+import android.app.Dialog
+import android.os.Bundle
+import com.afollestad.materialdialogs.MaterialDialog
+import eu.kanade.tachiyomi.R
+import eu.kanade.tachiyomi.data.preference.PreferencesHelper
+import eu.kanade.tachiyomi.ui.base.controller.DialogController
+import exh.md.similar.SimilarUpdateJob
+import uy.kohesive.injekt.Injekt
+import uy.kohesive.injekt.api.get
+
+class EnableMangaDexSimilarDialogController : DialogController() {
+
+    override fun onCreateDialog(savedViewState: Bundle?): Dialog {
+        val activity = activity!!
+        val preferences = Injekt.get<PreferencesHelper>()
+        return MaterialDialog(activity)
+            .title(text = activity.getString(R.string.similar_ask_to_enable_title))
+            .message(R.string.similar_ask_to_enable)
+            .negativeButton(R.string.similar_ask_to_enable_no, activity.getString(R.string.similar_ask_to_enable_no))
+            .positiveButton(R.string.similar_ask_to_enable_yes, activity.getString(R.string.similar_ask_to_enable_yes)) {
+                preferences.mangadexSimilarEnabled().set(true)
+                SimilarUpdateJob.setupTask(activity)
+            }
+    }
+}

app/src/main/java/exh/md/similar/ui/MangaDexSimilarController.kt

@@ -0,0 +1,55 @@
+package exh.md.similar.ui
+
+import android.os.Bundle
+import android.view.Menu
+import androidx.core.os.bundleOf
+import eu.kanade.tachiyomi.R
+import eu.kanade.tachiyomi.data.database.models.Manga
+import eu.kanade.tachiyomi.source.CatalogueSource
+import eu.kanade.tachiyomi.ui.browse.source.browse.BrowseSourceController
+import eu.kanade.tachiyomi.ui.browse.source.browse.BrowseSourcePresenter
+
+/**
+ * Controller that shows the latest manga from the catalogue. Inherit [BrowseSourceController].
+ */
+class MangaDexSimilarController(bundle: Bundle) : BrowseSourceController(bundle) {
+
+    constructor(manga: Manga, source: CatalogueSource) : this(
+        bundleOf(
+            MANGA_ID to manga.id!!,
+            SOURCE_ID_KEY to source.id
+        )
+    )
+
+    override fun getTitle(): String? {
+        return view?.context?.getString(R.string.similar)
+    }
+
+    override fun createPresenter(): BrowseSourcePresenter {
+        return MangaDexSimilarPresenter(args.getLong(MANGA_ID), args.getLong(SOURCE_ID_KEY))
+    }
+
+    override fun onPrepareOptionsMenu(menu: Menu) {
+        super.onPrepareOptionsMenu(menu)
+        menu.findItem(R.id.action_search).isVisible = false
+        menu.findItem(R.id.action_open_in_web_view).isVisible = false
+        menu.findItem(R.id.action_settings).isVisible = false
+    }
+
+    override fun initFilterSheet() {
+        // No-op: we don't allow filtering in similar
+    }
+
+    override fun onItemLongClick(position: Int) {
+        return
+    }
+
+    override fun onAddPageError(error: Throwable) {
+        super.onAddPageError(error)
+        binding.emptyView.show("No Similar Manga found")
+    }
+
+    companion object {
+        const val MANGA_ID = "manga_id"
+    }
+}

app/src/main/java/exh/md/similar/ui/MangaDexSimilarPager.kt

@@ -0,0 +1,29 @@
+package exh.md.similar.ui
+
+import eu.kanade.tachiyomi.data.database.models.Manga
+import eu.kanade.tachiyomi.source.model.MangasPage
+import eu.kanade.tachiyomi.source.online.all.MangaDex
+import eu.kanade.tachiyomi.ui.browse.source.browse.NoResultsException
+import eu.kanade.tachiyomi.ui.browse.source.browse.Pager
+import rx.Observable
+import rx.android.schedulers.AndroidSchedulers
+import rx.schedulers.Schedulers
+
+/**
+ * MangaDexSimilarPager inherited from the general Pager.
+ */
+class MangaDexSimilarPager(val manga: Manga, val source: MangaDex) : Pager() {
+
+    override fun requestNext(): Observable<MangasPage> {
+        return source.fetchMangaSimilar(manga)
+            .subscribeOn(Schedulers.io())
+            .observeOn(AndroidSchedulers.mainThread())
+            .doOnNext {
+                if (it.mangas.isNotEmpty()) {
+                    onPageReceived(it)
+                } else {
+                    throw NoResultsException()
+                }
+            }
+    }
+}

app/src/main/java/exh/md/similar/ui/MangaDexSimilarPresenter.kt

@@ -0,0 +1,26 @@
+package exh.md.similar.ui
+
+import eu.kanade.tachiyomi.data.database.DatabaseHelper
+import eu.kanade.tachiyomi.data.database.models.Manga
+import eu.kanade.tachiyomi.source.model.FilterList
+import eu.kanade.tachiyomi.source.online.all.MangaDex
+import eu.kanade.tachiyomi.ui.browse.source.browse.BrowseSourcePresenter
+import eu.kanade.tachiyomi.ui.browse.source.browse.Pager
+import exh.source.EnhancedHttpSource.Companion.getMainSource
+import uy.kohesive.injekt.injectLazy
+
+/**
+ * Presenter of [MangaDexSimilarController]. Inherit BrowseCataloguePresenter.
+ */
+class MangaDexSimilarPresenter(val mangaId: Long, sourceId: Long) : BrowseSourcePresenter(sourceId) {
+
+    var manga: Manga? = null
+
+    val db: DatabaseHelper by injectLazy()
+
+    override fun createPager(query: String, filters: FilterList): Pager {
+        val sourceAsMangaDex = source.getMainSource() as MangaDex
+        this.manga = db.getManga(mangaId).executeAsBlocking()
+        return MangaDexSimilarPager(manga!!, sourceAsMangaDex)
+    }
+}

app/src/main/java/exh/recs/RecommendsController.kt

@@ -0,0 +1,70 @@
+package exh.recs
+
+import android.os.Bundle
+import android.view.Menu
+import android.view.View
+import androidx.core.os.bundleOf
+import eu.kanade.tachiyomi.R
+import eu.kanade.tachiyomi.data.database.models.Manga
+import eu.kanade.tachiyomi.source.CatalogueSource
+import eu.kanade.tachiyomi.ui.base.controller.withFadeTransaction
+import eu.kanade.tachiyomi.ui.browse.source.SourceController
+import eu.kanade.tachiyomi.ui.browse.source.browse.BrowseSourceController
+import eu.kanade.tachiyomi.ui.browse.source.browse.SourceItem
+
+/**
+ * Controller that shows the latest manga from the catalogue. Inherit [BrowseSourceController].
+ */
+class RecommendsController(bundle: Bundle) : BrowseSourceController(bundle) {
+
+    constructor(manga: Manga, source: CatalogueSource) : this(
+        bundleOf(
+            MANGA_ID to manga.id!!,
+            SOURCE_ID_KEY to source.id
+        )
+    )
+
+    override fun getTitle(): String? {
+        return (presenter as? RecommendsPresenter)?.manga?.title
+    }
+
+    override fun createPresenter(): RecommendsPresenter {
+        return RecommendsPresenter(args.getLong(MANGA_ID), args.getLong(SOURCE_ID_KEY))
+    }
+
+    override fun onPrepareOptionsMenu(menu: Menu) {
+        super.onPrepareOptionsMenu(menu)
+        menu.findItem(R.id.action_search).isVisible = false
+        menu.findItem(R.id.action_open_in_web_view).isVisible = false
+        menu.findItem(R.id.action_settings).isVisible = false
+    }
+
+    override fun initFilterSheet() {
+        // No-op: we don't allow filtering in recs
+    }
+
+    override fun onItemClick(view: View, position: Int): Boolean {
+        val item = adapter?.getItem(position) as? SourceItem ?: return false
+        openSmartSearch(item.manga.originalTitle)
+        return true
+    }
+
+    private fun openSmartSearch(title: String) {
+        val smartSearchConfig = SourceController.SmartSearchConfig(title)
+        router.pushController(
+            SourceController(
+                bundleOf(
+                    SourceController.SMART_SEARCH_CONFIG to smartSearchConfig
+                )
+            ).withFadeTransaction()
+        )
+    }
+
+    override fun onItemLongClick(position: Int) {
+        return
+    }
+
+    companion object {
+        const val MANGA_ID = "manga_id"
+    }
+}

app/src/main/java/exh/recs/RecommendsPager.kt

@@ -1,9 +1,10 @@
-package eu.kanade.tachiyomi.ui.browse.source.browse
+package exh.recs
 
 import eu.kanade.tachiyomi.data.database.models.Manga
 import eu.kanade.tachiyomi.network.await
 import eu.kanade.tachiyomi.source.model.MangasPage
 import eu.kanade.tachiyomi.source.model.SMangaImpl
+import eu.kanade.tachiyomi.ui.browse.source.browse.Pager
 import exh.util.MangaType
 import exh.util.mangaType
 import kotlinx.coroutines.CoroutineExceptionHandler

app/src/main/java/exh/recs/RecommendsPresenter.kt

@@ -0,0 +1,23 @@
+package exh.recs
+
+import eu.kanade.tachiyomi.data.database.DatabaseHelper
+import eu.kanade.tachiyomi.data.database.models.Manga
+import eu.kanade.tachiyomi.source.model.FilterList
+import eu.kanade.tachiyomi.ui.browse.source.browse.BrowseSourcePresenter
+import eu.kanade.tachiyomi.ui.browse.source.browse.Pager
+import uy.kohesive.injekt.injectLazy
+
+/**
+ * Presenter of [RecommendsController]. Inherit BrowseCataloguePresenter.
+ */
+class RecommendsPresenter(val mangaId: Long, sourceId: Long) : BrowseSourcePresenter(sourceId) {
+
+    var manga: Manga? = null
+
+    val db: DatabaseHelper by injectLazy()
+
+    override fun createPager(query: String, filters: FilterList): Pager {
+        this.manga = db.getManga(mangaId).executeAsBlocking()
+        return RecommendsPager(manga!!)
+    }
+}

app/src/main/res/values/strings_sy.xml

@@ -32,6 +32,7 @@
     <string name="pref_category_all_sources">All Sources</string>
     <string name="pref_category_eh">E-Hentai</string>
     <string name="pref_category_fork">Fork Settings</string>
+    <string name="pref_category_mangadex">MangaDex</string>
 
 
     <!-- EH Settings -->
@@ -573,4 +574,37 @@
     <string name="metadata_corrupted">Metadata corrupted, please refresh the manga</string>
     <string name="no_scanlators">No scanlators available</string>
 
+    <!-- Similar -->
+    <string name="similar">Similar manga</string>
+    <string name="similar_loading_percent">Updating similar manga (%1$d / %2$d updated)</string>
+    <string name="similar_loading_complete">Updating similar manga complete</string>
+    <string name="similar_loading_complete_error">Error trying to load/process similar manga</string>
+    <string name="similar_loading_progress_start">Downloading similar manga data file…</string>
+    <string name="similar_ask_to_enable_title">Enable Similar Manga?</string>
+    <string name="similar_ask_to_enable">
+        Would you like to enable similar manga recommendations?
+        This will download approximately 9 MB of data if enabled right now.
+        You can always enable it in the Settings / Mangadex menu.
+    </string>
+    <string name="similar_ask_to_enable_yes">Enable</string>
+    <string name="similar_ask_to_enable_no">Skip</string>
+    <string name="similar_settings">Similar Manga Settings</string>
+    <string name="similar_screen">Show similar manga</string>
+    <string name="similar_manually_update">Pull latest database</string>
+    <string name="similar_manually_toast">Starting manual update</string>
+    <string name="similar_manually_update_message">
+        Download the latest similar manga database.
+        This is around 9MB in size and is updated daily.
+    </string>
+    <string name="similar_update_fequency">Similar update frequency</string>
+    <string name="similar_screen_summary_message">
+        This is a feature where one can get manga recommendations.
+        This is a recommendation system outside of MangaDex, and works by matching by genres,
+        demographics, content type, themes, and then using term frequency–inverse document frequency (tf–idf) to get the
+        similarity of two manga\'s descriptions. When enabled this file will download immediately!! The file is about 9 MB in size.
+    </string>
+    <string name="similar_credit_message">
+        For more information and to view the source code:\n%s
+    </string>
+
 </resources>