package at.hannibal2.skyhanni.config

import at.hannibal2.skyhanni.SkyHanniMod
import at.hannibal2.skyhanni.config.core.config.Position
import at.hannibal2.skyhanni.config.core.config.PositionList
import at.hannibal2.skyhanni.data.jsonobjects.local.FriendsJson
import at.hannibal2.skyhanni.data.jsonobjects.local.JacobContestsJson
import at.hannibal2.skyhanni.data.jsonobjects.local.KnownFeaturesJson
import at.hannibal2.skyhanni.data.jsonobjects.local.VisualWordsJson
import at.hannibal2.skyhanni.events.LorenzEvent
import at.hannibal2.skyhanni.features.misc.update.UpdateManager
import at.hannibal2.skyhanni.test.command.ErrorManager
import at.hannibal2.skyhanni.utils.ChatUtils
import at.hannibal2.skyhanni.utils.DelayedRun
import at.hannibal2.skyhanni.utils.IdentityCharacteristics
import at.hannibal2.skyhanni.utils.LorenzLogger
import at.hannibal2.skyhanni.utils.LorenzUtils
import at.hannibal2.skyhanni.utils.SimpleTimeMark
import at.hannibal2.skyhanni.utils.json.BaseGsonBuilder
import at.hannibal2.skyhanni.utils.system.PlatformUtils
import com.google.gson.Gson
import com.google.gson.GsonBuilder
import com.google.gson.JsonObject
import com.google.gson.TypeAdapterFactory
import io.github.notenoughupdates.moulconfig.annotations.ConfigLink
import io.github.notenoughupdates.moulconfig.processor.BuiltinMoulConfigGuis
import io.github.notenoughupdates.moulconfig.processor.ConfigProcessorDriver
import io.github.notenoughupdates.moulconfig.processor.MoulConfigProcessor
import java.io.BufferedReader
import java.io.BufferedWriter
import java.io.File
import java.io.FileInputStream
import java.io.FileOutputStream
import java.io.IOException
import java.io.InputStreamReader
import java.io.OutputStreamWriter
import java.nio.charset.StandardCharsets
import java.nio.file.Files
import java.nio.file.StandardCopyOption
import java.util.EnumMap
import kotlin.concurrent.fixedRateTimer
import kotlin.reflect.KMutableProperty0

private fun GsonBuilder.registerIfBeta(create: TypeAdapterFactory): GsonBuilder {
    return if (LorenzUtils.isBetaVersion()) {
        registerTypeAdapterFactory(create)
    } else this
}

class ConfigManager {
    companion object {

        val gson: Gson = BaseGsonBuilder.gson()
//             .registerIfBeta(FeatureTogglesByDefaultAdapter)
            .create()

        var configDirectory = File("config/skyhanni")
    }

    private val logger = LorenzLogger("config_manager")

    private val jsonHolder: Map<ConfigFileType, Any> = EnumMap(ConfigFileType::class.java)

    lateinit var processor: MoulConfigProcessor<Features>
    private var disableSaving = false

    private fun setConfigHolder(type: ConfigFileType, value: Any) {
        require(value.javaClass == type.clazz)
        @Suppress("UNCHECKED_CAST")
        (type.property as KMutableProperty0<Any>).set(value)
        (jsonHolder as MutableMap<ConfigFileType, Any>)[type] = value
    }

    fun firstLoad() {
        if (jsonHolder.isNotEmpty()) {
            logger.log("Loading config despite config being already loaded?")
        }
        configDirectory.mkdirs()


        for (fileType in ConfigFileType.entries) {
            setConfigHolder(fileType, firstLoadFile(fileType.file, fileType, fileType.clazz.newInstance()))
        }

        // TODO use SecondPassedEvent
        fixedRateTimer(name = "skyhanni-config-auto-save", period = 60_000L, initialDelay = 60_000L) {
            saveConfig(ConfigFileType.FEATURES, "auto-save-60s")
        }

        val features = SkyHanniMod.feature
        processor = MoulConfigProcessor(SkyHanniMod.feature)
        BuiltinMoulConfigGuis.addProcessors(processor)
        UpdateManager.injectConfigProcessor(processor)
        ConfigProcessorDriver(processor).processConfig(features)

        try {
            findPositionLinks(features, mutableSetOf())
        } catch (e: Exception) {
            if (LorenzEvent.isInGuardedEventHandler) throw e
        }
    }

    // Some position elements don't need config links as they don't have a config option.
    private val ignoredMissingConfigLinks = listOf(
        // commands
        "features.garden.GardenConfig.cropSpeedMeterPos",
        "features.misc.MiscConfig.collectionCounterPos",
        "features.misc.MiscConfig.carryPosition",
        "features.misc.MiscConfig.lockedMouseDisplay",

        // debug features
        "features.dev.DebugConfig.trackSoundPosition",
        "features.dev.DebugConfig.trackParticlePosition",
        "features.dev.DevConfig.debugPos",
        "features.dev.DevConfig.debugLocationPos",
        "features.dev.DevConfig.debugItemPos",
    )

    private fun findPositionLinks(obj: Any?, slog: MutableSet<IdentityCharacteristics<Any>>) {
        if (obj == null) return
        if (!obj.javaClass.name.startsWith("at.hannibal2.skyhanni.")) return
        val ic = IdentityCharacteristics(obj)
        if (ic in slog) return
        slog.add(ic)
        var missingConfigLink = false
        for (field in obj.javaClass.fields) {
            field.isAccessible = true
            if (field.type != Position::class.java && field.type != PositionList::class.java) {
                findPositionLinks(field.get(obj), slog)
                continue
            }
            val configLink = field.getAnnotation(ConfigLink::class.java)
            if (configLink == null) {
                if (PlatformUtils.isDevEnvironment) {
                    var name = "${field.declaringClass.name}.${field.name}"
                    name = name.replace("at.hannibal2.skyhanni.config.", "")
                    if (name !in ignoredMissingConfigLinks) {
                        println("WEE WOO WEE WOO HIER FEHLT EIN @CONFIGLINK: $name")
                        missingConfigLink = true
                    }
                }
                continue
            }
            if (field.type == Position::class.java) {
                val position = field.get(obj) as Position
                position.setLink(configLink)
            } else if (field.type == PositionList::class.java) {
                val list = field.get(obj) as PositionList
                list.setLink(configLink)
            }
        }
        if (missingConfigLink) {
            println("")
            println("This crash is here to remind you to fix the missing @ConfigLink annotation over your new config position config element.")
            println("")
            println("Steps to fix:")
            println("1. Search for `WEE WOO WEE WOO` in the console output.")
            println("2. Either add the Config Link.")
            println("3. Or add the name to ignoredMissingConfigLinks.")
            println("")
            LorenzUtils.shutdownMinecraft("Missing Config Link")
        }
    }

    private fun firstLoadFile(file: File?, fileType: ConfigFileType, defaultValue: Any): Any {
        val fileName = fileType.fileName
        logger.log("Trying to load $fileName from $file")
        var output: Any? = defaultValue

        if (file!!.exists()) {
            try {
                val inputStreamReader = InputStreamReader(FileInputStream(file), StandardCharsets.UTF_8)
                val bufferedReader = BufferedReader(inputStreamReader)
                val lenientGson = BaseGsonBuilder.lenientGson().create()

                logger.log("load-$fileName-now")

                output = if (fileType == ConfigFileType.FEATURES) {
                    val jsonObject = lenientGson.fromJson(bufferedReader.readText(), JsonObject::class.java)
                    val newJsonObject = ConfigUpdaterMigrator.fixConfig(jsonObject)
                    val run = { lenientGson.fromJson(newJsonObject, defaultValue.javaClass) }
                    if (PlatformUtils.isDevEnvironment) {
                        try {
                            run()
                        } catch (e: Throwable) {
                            logger.log(e.stackTraceToString())
                            LorenzUtils.shutdownMinecraft("Config is corrupt inside development environment.")
                        }
                    } else {
                        run()
                    }
                } else {
                    lenientGson.fromJson(bufferedReader.readText(), defaultValue.javaClass)
                }

                logger.log("Loaded $fileName from file")
            } catch (e: Exception) {
                logger.log(e.stackTraceToString())
                val backupFile = file.resolveSibling("$fileName-${SimpleTimeMark.now().toMillis()}-backup.json")
                logger.log("Exception while reading $file. Will load blank $fileName and save backup to $backupFile")
                logger.log("Exception was $e")
                try {
                    file.copyTo(backupFile)
                } catch (e: Exception) {
                    logger.log("Could not create backup for $fileName file")
                    logger.log(e.stackTraceToString())
                }
            }
        }

        if (output == defaultValue) {
            logger.log("Setting $fileName to be blank as it did not exist. It will be saved once something is written to it")
        }
        if (output == null) {
            logger.log("Setting $fileName to be blank as it was null. It will be saved once something is written to it")
            output = defaultValue
        }

        return output
    }

    fun saveConfig(fileType: ConfigFileType, reason: String) {
        val json = jsonHolder[fileType] ?: error("Could not find json object for $fileType")
        saveFile(fileType.file, fileType.fileName, json, reason)
    }

    private fun saveFile(file: File?, fileName: String, data: Any, reason: String) {
        if (disableSaving) return
        logger.log("saveConfig: $reason")
        if (file == null) throw Error("Can not save $fileName, ${fileName}File is null!")
        try {
            logger.log("Saving $fileName file")
            file.parentFile.mkdirs()
            val unit = file.parentFile.resolve("$fileName.json.write")
            unit.createNewFile()
            BufferedWriter(OutputStreamWriter(FileOutputStream(unit), StandardCharsets.UTF_8)).use { writer ->
                writer.write(gson.toJson(data))
            }
            // Perform move — which is atomic, unlike writing — after writing is done.
            move(unit, file, reason)
        } catch (e: IOException) {
            logger.log("Could not save $fileName file to $file")
            logger.log(e.stackTraceToString())
        }
    }

    private fun move(unit: File, file: File, reason: String, loop: Int = 0) {
        try {
            Files.move(
                unit.toPath(),
                file.toPath(),
                StandardCopyOption.REPLACE_EXISTING,
                StandardCopyOption.ATOMIC_MOVE,
            )
        } catch (e: AccessDeniedException) {
            if (loop == 5) {
                ErrorManager.logErrorWithData(
                    e,
                    "could not save config.",
                    "config save reason" to reason,
                )
                return
            }
            ChatUtils.debug("config save AccessDeniedException! (loop $loop)")
            DelayedRun.runNextTick {
                move(unit, file, reason, loop + 1)
            }
        }
    }

    fun disableSaving() {
        disableSaving = true
    }
}

enum class ConfigFileType(val fileName: String, val clazz: Class<*>, val property: KMutableProperty0<*>) {
    FEATURES("config", Features::class.java, SkyHanniMod::feature),
    SACKS("sacks", SackData::class.java, SkyHanniMod::sackData),
    FRIENDS("friends", FriendsJson::class.java, SkyHanniMod::friendsData),
    KNOWN_FEATURES("known_features", KnownFeaturesJson::class.java, SkyHanniMod::knownFeaturesData),
    JACOB_CONTESTS("jacob_contests", JacobContestsJson::class.java, SkyHanniMod::jacobContestsData),
    VISUAL_WORDS("visual_words", VisualWordsJson::class.java, SkyHanniMod::visualWordsData),
    ;

    val file by lazy { File(ConfigManager.configDirectory, "$fileName.json") }
}