package eu.kanade.tachiyomi.source

import android.content.Context
import eu.kanade.tachiyomi.data.download.DownloadManager
import eu.kanade.tachiyomi.extension.ExtensionManager
import eu.kanade.tachiyomi.source.online.HttpSource
import eu.kanade.tachiyomi.source.online.all.EHentai
import eu.kanade.tachiyomi.source.online.all.MangaDex
import eu.kanade.tachiyomi.source.online.all.MergedSource
import eu.kanade.tachiyomi.source.online.all.NHentai
import eu.kanade.tachiyomi.source.online.english.EightMuses
import eu.kanade.tachiyomi.source.online.english.HBrowse
import eu.kanade.tachiyomi.source.online.english.Pururin
import eu.kanade.tachiyomi.source.online.english.Tsumino
import exh.log.xLogD
import exh.source.BlacklistedSources
import exh.source.DelegatedHttpSource
import exh.source.EH_SOURCE_ID
import exh.source.EIGHTMUSES_SOURCE_ID
import exh.source.EXH_SOURCE_ID
import exh.source.EnhancedHttpSource
import exh.source.HBROWSE_SOURCE_ID
import exh.source.MERGED_SOURCE_ID
import exh.source.PURURIN_SOURCE_ID
import exh.source.TSUMINO_SOURCE_ID
import exh.source.handleSourceLibrary
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.Job
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.collectLatest
import kotlinx.coroutines.flow.combine
import kotlinx.coroutines.flow.map
import kotlinx.coroutines.launch
import kotlinx.coroutines.runBlocking
import tachiyomi.domain.UnsortedPreferences
import tachiyomi.domain.source.model.StubSource
import tachiyomi.domain.source.repository.StubSourceRepository
import tachiyomi.domain.source.service.SourceManager
import tachiyomi.source.local.LocalSource
import uy.kohesive.injekt.Injekt
import uy.kohesive.injekt.api.get
import uy.kohesive.injekt.injectLazy
import java.util.concurrent.ConcurrentHashMap
import kotlin.reflect.KClass

class AndroidSourceManager(
    private val context: Context,
    private val extensionManager: ExtensionManager,
    private val sourceRepository: StubSourceRepository,
) : SourceManager {

    private val downloadManager: DownloadManager by injectLazy()

    private val scope = CoroutineScope(Job() + Dispatchers.IO)

    private val sourcesMapFlow = MutableStateFlow(ConcurrentHashMap<Long, Source>())

    private val stubSourcesMap = ConcurrentHashMap<Long, StubSource>()

    override val catalogueSources: Flow<List<CatalogueSource>> = sourcesMapFlow.map {
        it.values.filterIsInstance<CatalogueSource>()
    }

    // SY -->
    private val preferences: UnsortedPreferences by injectLazy()
    // SY <--

    init {
        scope.launch {
            extensionManager.installedExtensionsFlow
                // SY -->
                .combine(preferences.enableExhentai().changes()) { extensions, enableExhentai ->
                    extensions to enableExhentai
                }
                // SY <--
                .collectLatest { (extensions, enableExhentai) ->
                    val mutableMap = ConcurrentHashMap<Long, Source>(
                        mapOf(
                            LocalSource.ID to LocalSource(
                                context,
                                Injekt.get(),
                                Injekt.get(),
                                // SY -->
                                preferences.allowLocalSourceHiddenFolders()::get,
                                // SY <--
                            ),
                        ),
                    ).apply {
                        // SY -->
                        put(EH_SOURCE_ID, EHentai(EH_SOURCE_ID, false, context))
                        if (enableExhentai) {
                            put(EXH_SOURCE_ID, EHentai(EXH_SOURCE_ID, true, context))
                        }
                        put(MERGED_SOURCE_ID, MergedSource())
                        // SY <--
                    }
                    extensions.forEach { extension ->
                        extension.sources.mapNotNull { it.toInternalSource() }.forEach {
                            mutableMap[it.id] = it
                            registerStubSource(it.toStubSource())
                        }
                    }
                    sourcesMapFlow.value = mutableMap
                }
        }

        scope.launch {
            sourceRepository.subscribeAll()
                .collectLatest { sources ->
                    val mutableMap = stubSourcesMap.toMutableMap()
                    sources.forEach {
                        mutableMap[it.id] = it
                    }
                }
        }
    }

    private fun Source.toInternalSource(): Source? {
        // EXH -->
        val sourceQName = this::class.qualifiedName
        val factories = DELEGATED_SOURCES.entries
            .filter { it.value.factory }
            .map { it.value.originalSourceQualifiedClassName }
        val delegate = if (sourceQName != null) {
            val matched = factories.find { sourceQName.startsWith(it) }
            if (matched != null) {
                DELEGATED_SOURCES[matched]
            } else {
                DELEGATED_SOURCES[sourceQName]
            }
        } else {
            null
        }
        val newSource = if (this is HttpSource && delegate != null) {
            xLogD("Delegating source: %s -> %s!", sourceQName, delegate.newSourceClass.qualifiedName)
            val enhancedSource = EnhancedHttpSource(
                this,
                delegate.newSourceClass.constructors.find { it.parameters.size == 2 }!!.call(this, context),
            )

            currentDelegatedSources[enhancedSource.originalSource.id] = DelegatedSource(
                enhancedSource.originalSource.name,
                enhancedSource.originalSource.id,
                enhancedSource.originalSource::class.qualifiedName ?: delegate.originalSourceQualifiedClassName,
                (enhancedSource.enhancedSource as DelegatedHttpSource)::class,
                delegate.factory,
            )
            enhancedSource
        } else {
            this
        }

        return if (id in BlacklistedSources.BLACKLISTED_EXT_SOURCES) {
            xLogD(
                "Removing blacklisted source: (id: %s, name: %s, lang: %s)!",
                id,
                name,
                (this as? CatalogueSource)?.lang,
            )
            null
        } else {
            newSource
        }
        // EXH <--
    }

    override fun get(sourceKey: Long): Source? {
        return sourcesMapFlow.value[sourceKey]
    }

    override fun getOrStub(sourceKey: Long): Source {
        return sourcesMapFlow.value[sourceKey] ?: stubSourcesMap.getOrPut(sourceKey) {
            runBlocking { createStubSource(sourceKey) }
        }
    }

    override fun getOnlineSources() = sourcesMapFlow.value.values.filterIsInstance<HttpSource>()

    override fun getCatalogueSources() = sourcesMapFlow.value.values.filterIsInstance<CatalogueSource>()

    override fun getStubSources(): List<StubSource> {
        val onlineSourceIds = getOnlineSources().map { it.id }
        return stubSourcesMap.values.filterNot { it.id in onlineSourceIds }
    }

    // SY -->
    override fun getVisibleOnlineSources() = sourcesMapFlow.value.values
        .filterIsInstance<HttpSource>()
        .filter {
            it.id !in BlacklistedSources.HIDDEN_SOURCES
        }

    override fun getVisibleCatalogueSources() = sourcesMapFlow.value.values
        .filterIsInstance<CatalogueSource>()
        .filter {
            it.id !in BlacklistedSources.HIDDEN_SOURCES
        }

    fun getDelegatedCatalogueSources() = sourcesMapFlow.value.values
        .filterIsInstance<EnhancedHttpSource>()
        .mapNotNull { enhancedHttpSource ->
            enhancedHttpSource.enhancedSource as? DelegatedHttpSource
        }
    // SY <--

    private fun registerStubSource(source: StubSource) {
        scope.launch {
            val dbSource = sourceRepository.getStubSource(source.id)
            if (dbSource == source) return@launch
            sourceRepository.upsertStubSource(source.id, source.lang, source.name)
            if (dbSource != null) {
                downloadManager.renameSource(dbSource, source)
            }
        }
    }

    private suspend fun createStubSource(id: Long): StubSource {
        sourceRepository.getStubSource(id)?.let {
            return it
        }
        extensionManager.getSourceData(id)?.let {
            registerStubSource(it)
            return it
        }
        return StubSource(id = id, lang = "", name = "")
    }

    // SY -->
    companion object {
        private const val fillInSourceId = Long.MAX_VALUE
        val DELEGATED_SOURCES = listOf(
            DelegatedSource(
                "Pururin",
                PURURIN_SOURCE_ID,
                "eu.kanade.tachiyomi.extension.en.pururin.Pururin",
                Pururin::class,
            ),
            DelegatedSource(
                "Tsumino",
                TSUMINO_SOURCE_ID,
                "eu.kanade.tachiyomi.extension.en.tsumino.Tsumino",
                Tsumino::class,
            ),
            DelegatedSource(
                "MangaDex",
                fillInSourceId,
                "eu.kanade.tachiyomi.extension.all.mangadex",
                MangaDex::class,
                true,
            ),
            DelegatedSource(
                "HBrowse",
                HBROWSE_SOURCE_ID,
                "eu.kanade.tachiyomi.extension.en.hbrowse.HBrowse",
                HBrowse::class,
            ),
            DelegatedSource(
                "8Muses",
                EIGHTMUSES_SOURCE_ID,
                "eu.kanade.tachiyomi.extension.en.eightmuses.EightMuses",
                EightMuses::class,
            ),
            DelegatedSource(
                "NHentai",
                fillInSourceId,
                "eu.kanade.tachiyomi.extension.all.nhentai.NHentai",
                NHentai::class,
                true,
            ),
        ).associateBy { it.originalSourceQualifiedClassName }

        val currentDelegatedSources: MutableMap<Long, DelegatedSource> =
            ListenMutableMap(mutableMapOf(), ::handleSourceLibrary)

        data class DelegatedSource(
            val sourceName: String,
            val sourceId: Long,
            val originalSourceQualifiedClassName: String,
            val newSourceClass: KClass<out DelegatedHttpSource>,
            val factory: Boolean = false,
        )
    }

    private class ListenMutableMap<K, V>(
        private val internalMap: MutableMap<K, V>,
        private val listener: () -> Unit,
    ) : MutableMap<K, V> by internalMap {
        override fun clear() {
            val clearResult = internalMap.clear()
            listener()
            return clearResult
        }

        override fun put(key: K, value: V): V? {
            val putResult = internalMap.put(key, value)
            if (putResult == null) {
                listener()
            }
            return putResult
        }

        override fun putAll(from: Map<out K, V>) {
            internalMap.putAll(from)
            listener()
        }

        override fun remove(key: K): V? {
            val removeResult = internalMap.remove(key)
            if (removeResult != null) {
                listener()
            }
            return removeResult
        }
    }

    // SY <--
}