installs/updates evergreenhud and it's addons

EvergreenHUDInstaller.kt

package dev.isxander.evergreenhud.installer

import co.uk.isxander.libinstaller.InstallerUtils
import org.apache.commons.io.FileUtils
import java.awt.Font
import java.io.*
import java.net.HttpURLConnection
import java.net.URL
import java.nio.charset.Charset
import java.util.jar.JarFile
import javax.swing.*

object EvergreenHUDInstaller {

    private const val coreUrl = "https://static.isxander.co.uk/evergreenhud/core/%s.jar"
    private const val coreVersion = "https://raw.githubusercontent.com/isXander/EvergreenHUD/main/version.json"

    fun install(mcDir: File) {
        val dataDir = File(mcDir, "evergreenhud")
        if (!dataDir.exists()) dataDir.mkdirs()

        installCore(dataDir)
        updateAddons(dataDir)

    }

    private fun installCore(dataDir: File) {
        val config = InstallerUtils.readFile(File(dataDir, "config/global.json"))
        val releaseChannel = config.optString("release_channel", "release")!!

        val localFile = File(dataDir, "metadata.json")
        val localVersion = InstallerUtils.readFile(localFile)
        val remoteVersion = InstallerUtils.fetchJSON(coreVersion)

        val currentVersion = localVersion.optString(releaseChannel)
        val latestVersion = remoteVersion.optString(releaseChannel)!!

        val outputFile = File(dataDir, "core.jar")
        if (currentVersion == null
            || localVersion.optString("release_channel", "release") != releaseChannel
            || latestVersion != currentVersion) {
            if (InstallerUtils.download(String.format(coreUrl, latestVersion), outputFile, "EvergreenHUD", "${if (outputFile.exists()) "Updating" else "Downloading"} core...")) {
                localVersion.put("release_channel", releaseChannel)
                localVersion.put(releaseChannel, latestVersion)
                FileUtils.write(localFile, localVersion.toString(), Charset.defaultCharset())

                InstallerUtils.addToClasspath(outputFile)
            }
        }
    }

    private fun updateAddons(dataDir: File) {
        val addonsFolderFile = File(dataDir, "addons")
        if (!addonsFolderFile.exists()) addonsFolderFile.mkdirs()
        val jarFiles = addonsFolderFile.listFiles { _, name -> name.endsWith(".jar") }!!
        val remove = ArrayList<File>()

        for (addonFile in jarFiles) {
            JarFile(addonFile).use { jar ->
                val entry = jar.getEntry("evergreen.addon.json")
                val addonJson = InstallerUtils.readFile(File(entry.name))
                val addonName = addonJson.optString("name", "Unknown")!!

                val updateUrl = addonJson.optString("updateUrl", null)
                if (updateUrl != null) {
                    val updateJson = InstallerUtils.fetchJSON(updateUrl)
                    val currentVersion = addonJson.optString("version", "1.0")!!
                    val latestVersion = updateJson.optString("version", "1.0")!!

                    if (currentVersion != latestVersion) {
                        InstallerUtils.download(updateJson.optString("download", null)!!, File(addonsFolderFile, "$addonName ($latestVersion).jar"), "EvergreenHUD", "Updating $addonName addon...")
                        remove.add(addonFile)
                    }
                }
            }
        }

        for (file in remove) {
            file.delete()
        }
    }

}