package app.revanced.utils

import app.revanced.cli.command.MainCommand.logger
import app.revanced.patcher.Patcher
import app.revanced.patcher.data.Data
import app.revanced.patcher.extensions.PatchExtensions.options
import app.revanced.patcher.extensions.PatchExtensions.patchName
import app.revanced.patcher.patch.Patch
import cc.ekblad.toml.encodeToString
import cc.ekblad.toml.model.TomlValue
import cc.ekblad.toml.serialization.from
import cc.ekblad.toml.tomlMapper
import java.io.File

private typealias PatchList = List<Class<out Patch<Data>>>
private typealias OptionsMap = MutableMap<String, MutableMap<String, Any>>

object OptionsLoader {
    @JvmStatic
    private val mapper = tomlMapper {}

    @JvmStatic
    fun init(file: File, patches: PatchList) {
        if (!file.exists()) file.createNewFile()
        val map = mapper.decodeWithDefaults(generateDefaults(patches), TomlValue.from(file.toPath()))
        readAndSet(map, patches)
        save(map, file)
    }

    private fun readAndSet(map: OptionsMap, patches: PatchList) {
        for ((patchName, options) in map) {
            val patch = patches.find { it.patchName == patchName } ?: continue
            val patchOptions = patch.options ?: continue
            for ((key, value) in options) {
                if (value == "null") { // backwards compatibility, subject to removal
                    options.remove(key)
                    continue
                }
                try {
                    patchOptions[key] = value
                } catch (e: Exception) {
                    logger.error("Error while setting option $key for patch $patchName: ${e.message}")
                    e.printStackTrace()
                }
            }
        }
    }

    private fun save(map: OptionsMap, file: File) {
        val toml = mapper.encodeToString(map)
        file.writeText(
            """
                # A list of options for each patch.
                # This file does not contain all options by default.
                # Run the CLI with the "--list --with-options" flags to see all available options.
                # You can also run the CLI with the aforementioned flags and a patch name to see all available options for that patch.
                # To set an option, add a line with the format "option = value" or set the value if the option already exists.
                # To reset an option to its default value, delete the line.
                # To reset all options to their default values, delete this file.
                # 
                # This file was generated by ReVanced Patcher version ${Patcher.version}.
            """.trimIndent() + "\n\n$toml"
        )
    }

    private fun generateDefaults(patches: PatchList) = buildMap {
        for (patch in patches) {
            val options = patch.options ?: continue
            if (!options.iterator().hasNext()) continue
            put(patch.patchName, buildMap {
                for (option in options) {
                    put(option.key, option.value ?: continue)
                }
            } as MutableMap)
        }
    } as MutableMap
}