index/src/main/kotlin/moe/odango/index/sync/AniDBTitleSync.kt

package moe.odango.index.sync

import com.github.kittinunf.fuel.coroutines.awaitByteArrayResponseResult
import com.github.kittinunf.fuel.httpDownload
import io.requery.Persistable
import io.requery.kotlin.`in`
import io.requery.kotlin.eq
import io.requery.kotlin.invoke
import io.requery.sql.KotlinEntityDataStore
import moe.odango.index.di
import moe.odango.index.entity.Anime
import moe.odango.index.entity.Title
import moe.odango.index.utils.InfoSource
import moe.odango.index.utils.XMLOutputStreamReader
import org.apache.commons.compress.compressors.gzip.GzipCompressorInputStream
import org.kodein.di.instance
import java.io.File
import java.io.InputStream
import java.util.concurrent.TimeUnit
import java.util.zip.InflaterOutputStream

class AniDBTitleSync : ScheduledSync(1, TimeUnit.DAYS) {
    private val entityStore by di.instance<KotlinEntityDataStore<Persistable>>()

    data class AniDBTitle(val aid: Long, val name: String, val type: String, val language: String)

    override suspend fun run() {


        val (feeder, cacheMap) = getFeeder()

        "https://anidb.net/api/anime-titles.xml.gz"
            .httpDownload()
            .streamDestination { _, _ ->
                InflaterOutputStream(feeder) to { InputStream.nullInputStream() }
            }
            .awaitByteArrayResponseResult()

        syncTitles(cacheMap)
    }

    private fun getFeeder(): Pair<XMLOutputStreamReader, MutableMap<Long, MutableList<AniDBTitle>>> {
        var animeId: Long = 0;
        var language = ""
        var type = ""
        var title = ""
        val cacheMap = mutableMapOf<Long, MutableList<AniDBTitle>>()

        return XMLOutputStreamReader {
            if (isStartElement) {
                if (name.localPart == "anime") {
                    animeId = getAttributeValue("", "aid").toLong()
                }

                if (name.localPart == "title") {
                    title = ""
                    type = getAttributeValue("", "type")
                    language = getAttributeValue("http://www.w3.org/XML/1998/namespace", "lang")
                }
            }

            if (isCharacters) {
                title += text
            }

            if (isEndElement) {
                if (name.localPart == "title") {
                    cacheMap
                        .getOrPut(animeId, ::mutableListOf)
                        .add(AniDBTitle(animeId, title, type, language))

                    println("$animeId => [$type/$language] $title")

                    title = ""
                }

                if (name.localPart == "anime") {
                    if (cacheMap.size >= 100) {
                        syncTitles(cacheMap)

                        cacheMap.clear()
                    }
                }
            }
        } to cacheMap
    }

    fun syncWithFile(file: File) {
        val (feeder, cacheMap) = getFeeder()

        file
            .inputStream()
            .let {
                if (file.name.endsWith(".gz")) {
                    GzipCompressorInputStream(it)
                } else {
                    it
                }
            }
            .transferTo(feeder)
        syncTitles(cacheMap)
    }

    private fun syncTitles(cacheMap: Map<Long, List<AniDBTitle>>) {
        val ids = cacheMap.keys

        val (animes, titles) = entityStore {
            val animes = (select(Anime::class) where (Anime::aniDbId `in` ids)).get().toList()

            val query = select(Title::class) where (Title::anime `in` animes) and (Title::source eq InfoSource.AniDB)
            animes to query().toList()
        }

        val animeById = animes.associateBy { it.aniDbId!! }
        val titlesByAniDBId = titles.groupBy {
            it.anime.aniDbId!!
        }

        val newAnimes = mutableListOf<Pair<Long, List<AniDBTitle>>>()

        entityStore.withTransaction {
            for ((aniDb, newTitles) in cacheMap) {
                val newAniDbTitlesSet = newTitles.map { Triple(it.language, it.type, it.name) }.toMutableSet()
                val anime = animeById[aniDb]
                if (anime == null) {
                    newAnimes.add(aniDb to newTitles)
                    continue
                }

                val dbTitles = titlesByAniDBId[aniDb] ?: listOf()

                for (dbTitle in dbTitles) {
                    if (!newAniDbTitlesSet.remove(
                            Triple(
                                dbTitle.language,
                                dbTitle.type.toAniDBString(),
                                dbTitle.name
                            )
                        )
                    ) {
                        // If it wasn't in the set, remove it from the DB
                        delete(dbTitle)
                    }
                }

                for ((language, type, name) in newAniDbTitlesSet) {
                    val title = Title {
                        setAnime(anime)
                        setLanguage(language)
                        setType(Title.TitleType.fromAniDBString(type))
                        setSource(InfoSource.AniDB)
                        this.name = name
                    }

                    insert(title)
                }
            }

            for ((aniDb, aniDbTitles) in newAnimes) {
                val anime = Anime {
                    aniDbId = aniDb
                }

                insert(anime)

                for (aniDbTitle in aniDbTitles) {
                    insert(Title {
                        setAnime(anime)
                        setLanguage(aniDbTitle.language)
                        setType(Title.TitleType.fromAniDBString(aniDbTitle.type))
                        setSource(InfoSource.AniDB)
                        name = aniDbTitle.name
                    })
                }
            }
        }
    }
}