package tachiyomi.source.local

import android.content.Context
import eu.kanade.tachiyomi.source.CatalogueSource
import eu.kanade.tachiyomi.source.Source
import eu.kanade.tachiyomi.source.UnmeteredSource
import eu.kanade.tachiyomi.source.model.FilterList
import eu.kanade.tachiyomi.source.model.MangasPage
import eu.kanade.tachiyomi.source.model.SChapter
import eu.kanade.tachiyomi.source.model.SManga
import eu.kanade.tachiyomi.util.lang.compareToCaseInsensitiveNaturalOrder
import eu.kanade.tachiyomi.util.storage.EpubFile
import kotlinx.coroutines.runBlocking
import kotlinx.serialization.json.Json
import kotlinx.serialization.json.decodeFromStream
import logcat.LogPriority
import nl.adaptivity.xmlutil.AndroidXmlReader
import nl.adaptivity.xmlutil.serialization.XML
import tachiyomi.core.metadata.comicinfo.COMIC_INFO_FILE
import tachiyomi.core.metadata.comicinfo.ComicInfo
import tachiyomi.core.metadata.comicinfo.copyFromComicInfo
import tachiyomi.core.metadata.tachiyomi.MangaDetails
import tachiyomi.core.util.lang.withIOContext
import tachiyomi.core.util.system.ImageUtil
import tachiyomi.core.util.system.logcat
import tachiyomi.domain.chapter.service.ChapterRecognition
import tachiyomi.domain.manga.model.Manga
import tachiyomi.source.local.filter.OrderBy
import tachiyomi.source.local.image.LocalCoverManager
import tachiyomi.source.local.io.Archive
import tachiyomi.source.local.io.Format
import tachiyomi.source.local.io.LocalSourceFileSystem
import tachiyomi.source.local.metadata.fillChapterMetadata
import tachiyomi.source.local.metadata.fillMangaMetadata
import uy.kohesive.injekt.injectLazy
import java.io.File
import java.io.FileInputStream
import java.io.InputStream
import java.nio.charset.StandardCharsets
import java.util.zip.ZipFile
import kotlin.time.Duration.Companion.days
import com.github.junrar.Archive as JunrarArchive
import tachiyomi.domain.source.model.Source as DomainSource

actual class LocalSource(
    private val context: Context,
    private val fileSystem: LocalSourceFileSystem,
    private val coverManager: LocalCoverManager,
) : CatalogueSource, UnmeteredSource {

    private val json: Json by injectLazy()
    private val xml: XML by injectLazy()

    private val POPULAR_FILTERS = FilterList(OrderBy.Popular(context))
    private val LATEST_FILTERS = FilterList(OrderBy.Latest(context))

    override val name: String = context.getString(R.string.local_source)

    override val id: Long = ID

    override val lang: String = "other"

    override fun toString() = name

    override val supportsLatest: Boolean = true

    // Browse related
    override suspend fun getPopularManga(page: Int) = getSearchManga(page, "", POPULAR_FILTERS)

    override suspend fun getLatestUpdates(page: Int) = getSearchManga(page, "", LATEST_FILTERS)

    override suspend fun getSearchManga(page: Int, query: String, filters: FilterList): MangasPage {
        val baseDirsFiles = fileSystem.getFilesInBaseDirectories()
        val lastModifiedLimit by lazy { if (filters === LATEST_FILTERS) System.currentTimeMillis() - LATEST_THRESHOLD else 0L }
        var mangaDirs = baseDirsFiles
            // Filter out files that are hidden and is not a folder
            .filter { it.isDirectory && !it.name.startsWith('.') }
            .distinctBy { it.name }
            .filter { // Filter by query or last modified
                if (lastModifiedLimit == 0L) {
                    it.name.contains(query, ignoreCase = true)
                } else {
                    it.lastModified() >= lastModifiedLimit
                }
            }

        filters.forEach { filter ->
            when (filter) {
                is OrderBy.Popular -> {
                    mangaDirs = if (filter.state!!.ascending) {
                        mangaDirs.sortedWith(compareBy(String.CASE_INSENSITIVE_ORDER) { it.name })
                    } else {
                        mangaDirs.sortedWith(compareByDescending(String.CASE_INSENSITIVE_ORDER) { it.name })
                    }
                }
                is OrderBy.Latest -> {
                    mangaDirs = if (filter.state!!.ascending) {
                        mangaDirs.sortedBy(File::lastModified)
                    } else {
                        mangaDirs.sortedByDescending(File::lastModified)
                    }
                }

                else -> {
                    /* Do nothing */
                }
            }
        }

        // Transform mangaDirs to list of SManga
        val mangas = mangaDirs.map { mangaDir ->
            SManga.create().apply {
                title = mangaDir.name
                url = mangaDir.name

                // Try to find the cover
                coverManager.find(mangaDir.name)
                    ?.takeIf(File::exists)
                    ?.let { thumbnail_url = it.absolutePath }
            }
        }

        // Fetch chapters of all the manga
        mangas.forEach { manga ->
            runBlocking {
                val chapters = getChapterList(manga)
                if (chapters.isNotEmpty()) {
                    val chapter = chapters.last()
                    val format = getFormat(chapter)

                    if (format is Format.Epub) {
                        EpubFile(format.file).use { epub ->
                            epub.fillMangaMetadata(manga)
                        }
                    }

                    // Copy the cover from the first chapter found if not available
                    if (manga.thumbnail_url == null) {
                        updateCover(chapter, manga)
                    }
                }
            }
        }

        return MangasPage(mangas.toList(), false)
    }

    // Manga details related
    override suspend fun getMangaDetails(manga: SManga): SManga = withIOContext {
        coverManager.find(manga.url)?.let {
            manga.thumbnail_url = it.absolutePath
        }

        // Augment manga details based on metadata files
        try {
            val mangaDirFiles = fileSystem.getFilesInMangaDirectory(manga.url).toList()

            val comicInfoFile = mangaDirFiles
                .firstOrNull { it.name == COMIC_INFO_FILE }
            val noXmlFile = mangaDirFiles
                .firstOrNull { it.name == ".noxml" }
            val legacyJsonDetailsFile = mangaDirFiles
                .firstOrNull { it.extension == "json" }

            when {
                // Top level ComicInfo.xml
                comicInfoFile != null -> {
                    noXmlFile?.delete()
                    setMangaDetailsFromComicInfoFile(comicInfoFile.inputStream(), manga)
                }

                // TODO: automatically convert these to ComicInfo.xml
                legacyJsonDetailsFile != null -> {
                    json.decodeFromStream<MangaDetails>(legacyJsonDetailsFile.inputStream()).run {
                        title?.let { manga.title = it }
                        author?.let { manga.author = it }
                        artist?.let { manga.artist = it }
                        description?.let { manga.description = it }
                        genre?.let { manga.genre = it.joinToString() }
                        status?.let { manga.status = it }
                    }
                }

                // Copy ComicInfo.xml from chapter archive to top level if found
                noXmlFile == null -> {
                    val chapterArchives = mangaDirFiles
                        .filter(Archive::isSupported)
                        .toList()

                    val mangaDir = fileSystem.getMangaDirectory(manga.url)
                    val folderPath = mangaDir?.absolutePath

                    val copiedFile = copyComicInfoFileFromArchive(chapterArchives, folderPath)
                    if (copiedFile != null) {
                        setMangaDetailsFromComicInfoFile(copiedFile.inputStream(), manga)
                    } else {
                        // Avoid re-scanning
                        File("$folderPath/.noxml").createNewFile()
                    }
                }
            }
        } catch (e: Throwable) {
            logcat(LogPriority.ERROR, e) { "Error setting manga details from local metadata for ${manga.title}" }
        }

        return@withIOContext manga
    }

    private fun copyComicInfoFileFromArchive(chapterArchives: List<File>, folderPath: String?): File? {
        for (chapter in chapterArchives) {
            when (Format.valueOf(chapter)) {
                is Format.Zip -> {
                    ZipFile(chapter).use { zip: ZipFile ->
                        zip.getEntry(COMIC_INFO_FILE)?.let { comicInfoFile ->
                            zip.getInputStream(comicInfoFile).buffered().use { stream ->
                                return copyComicInfoFile(stream, folderPath)
                            }
                        }
                    }
                }
                is Format.Rar -> {
                    JunrarArchive(chapter).use { rar ->
                        rar.fileHeaders.firstOrNull { it.fileName == COMIC_INFO_FILE }?.let { comicInfoFile ->
                            rar.getInputStream(comicInfoFile).buffered().use { stream ->
                                return copyComicInfoFile(stream, folderPath)
                            }
                        }
                    }
                }
                else -> {}
            }
        }
        return null
    }

    private fun copyComicInfoFile(comicInfoFileStream: InputStream, folderPath: String?): File {
        return File("$folderPath/$COMIC_INFO_FILE").apply {
            outputStream().use { outputStream ->
                comicInfoFileStream.use { it.copyTo(outputStream) }
            }
        }
    }

    private fun setMangaDetailsFromComicInfoFile(stream: InputStream, manga: SManga) {
        val comicInfo = AndroidXmlReader(stream, StandardCharsets.UTF_8.name()).use {
            xml.decodeFromReader<ComicInfo>(it)
        }

        manga.copyFromComicInfo(comicInfo)
    }

    // Chapters
    override suspend fun getChapterList(manga: SManga): List<SChapter> {
        return fileSystem.getFilesInMangaDirectory(manga.url)
            // Only keep supported formats
            .filter { it.isDirectory || Archive.isSupported(it) }
            .map { chapterFile ->
                SChapter.create().apply {
                    url = "${manga.url}/${chapterFile.name}"
                    name = if (chapterFile.isDirectory) {
                        chapterFile.name
                    } else {
                        chapterFile.nameWithoutExtension
                    }
                    date_upload = chapterFile.lastModified()
                    chapter_number = ChapterRecognition
                        .parseChapterNumber(manga.title, this.name, this.chapter_number.toDouble())
                        .toFloat()

                    val format = Format.valueOf(chapterFile)
                    if (format is Format.Epub) {
                        EpubFile(format.file).use { epub ->
                            epub.fillChapterMetadata(this)
                        }
                    }
                }
            }
            .sortedWith { c1, c2 ->
                val c = c2.chapter_number.compareTo(c1.chapter_number)
                if (c == 0) c2.name.compareToCaseInsensitiveNaturalOrder(c1.name) else c
            }
            .toList()
    }

    // Filters
    override fun getFilterList() = FilterList(OrderBy.Popular(context))

    // Unused stuff
    override suspend fun getPageList(chapter: SChapter) = throw UnsupportedOperationException("Unused")

    fun getFormat(chapter: SChapter): Format {
        try {
            return fileSystem.getBaseDirectories()
                .map { dir -> File(dir, chapter.url) }
                .find { it.exists() }
                ?.let(Format.Companion::valueOf)
                ?: throw Exception(context.getString(R.string.chapter_not_found))
        } catch (e: Format.UnknownFormatException) {
            throw Exception(context.getString(R.string.local_invalid_format))
        } catch (e: Exception) {
            throw e
        }
    }

    private fun updateCover(chapter: SChapter, manga: SManga): File? {
        return try {
            when (val format = getFormat(chapter)) {
                is Format.Directory -> {
                    val entry = format.file.listFiles()
                        ?.sortedWith { f1, f2 -> f1.name.compareToCaseInsensitiveNaturalOrder(f2.name) }
                        ?.find { !it.isDirectory && ImageUtil.isImage(it.name) { FileInputStream(it) } }

                    entry?.let { coverManager.update(manga, it.inputStream()) }
                }
                is Format.Zip -> {
                    ZipFile(format.file).use { zip ->
                        val entry = zip.entries().toList()
                            .sortedWith { f1, f2 -> f1.name.compareToCaseInsensitiveNaturalOrder(f2.name) }
                            .find { !it.isDirectory && ImageUtil.isImage(it.name) { zip.getInputStream(it) } }

                        entry?.let { coverManager.update(manga, zip.getInputStream(it)) }
                    }
                }
                is Format.Rar -> {
                    JunrarArchive(format.file).use { archive ->
                        val entry = archive.fileHeaders
                            .sortedWith { f1, f2 -> f1.fileName.compareToCaseInsensitiveNaturalOrder(f2.fileName) }
                            .find { !it.isDirectory && ImageUtil.isImage(it.fileName) { archive.getInputStream(it) } }

                        entry?.let { coverManager.update(manga, archive.getInputStream(it)) }
                    }
                }
                is Format.Epub -> {
                    EpubFile(format.file).use { epub ->
                        val entry = epub.getImagesFromPages()
                            .firstOrNull()
                            ?.let { epub.getEntry(it) }

                        entry?.let { coverManager.update(manga, epub.getInputStream(it)) }
                    }
                }
            }
        } catch (e: Throwable) {
            logcat(LogPriority.ERROR, e) { "Error updating cover for ${manga.title}" }
            null
        }
    }

    companion object {
        const val ID = 0L
        const val HELP_URL = "https://tachiyomi.org/docs/guides/local-series/"

        private val LATEST_THRESHOLD = 7.days.inWholeMilliseconds
    }
}

fun Manga.isLocal(): Boolean = source == LocalSource.ID

fun Source.isLocal(): Boolean = id == LocalSource.ID

fun DomainSource.isLocal(): Boolean = id == LocalSource.ID