Run With Auth

Author: SmushyTaco

build.gradle.kts

@@ -1,3 +1,4 @@
+import com.google.gson.Gson
 import com.smushytaco.lwjgl_gradle.Preset
 import java.nio.file.Files
 
@@ -17,9 +18,62 @@ val javaVersion: Provider<Int> = libs.versions.java.map { it.toInt() }
 base.archivesName = modName
 group = modGroup.get()
 version = modVersion.get()
+
+class AccountsJson(val accounts: List<Account>)
+class Account(val profile: Profile, val ygg: YGG)
+class YGG(val token: String)
+class Profile(val name: String, val id: String)
+
+val prismAccountsFile = providers.provider {
+    val explicit = providers.gradleProperty("prism.accounts.file").orNull
+    if (explicit != null) {
+        val explicitFile = File(explicit)
+        if (explicitFile.exists()) return@provider explicitFile
+    }
+
+    val home = System.getProperty("user.home")
+
+    val candidates = buildList {
+        // Windows
+        System.getenv("APPDATA")?.let { add(File(it, "PrismLauncher/accounts.json")) }
+        System.getenv("HOMEPATH")?.let { add(File(it, "scoop/persist/prismlauncher/accounts.json")) }
+        // Linux / XDG
+        val xdgDataHome = System.getenv("XDG_DATA_HOME")
+        if (xdgDataHome != null) {
+            add(File(xdgDataHome, "PrismLauncher/accounts.json"))
+        } else {
+            add(File(home, ".local/share/PrismLauncher/accounts.json"))
+        }
+        // Flatpak
+        add(File(home, ".var/app/org.prismlauncher.PrismLauncher/data/PrismLauncher/accounts.json"))
+        // macOS
+        add(File(home, "Library/Application Support/PrismLauncher/accounts.json"))
+    }
+    candidates.firstOrNull(File::exists)
+}
+
 loom {
     customMinecraftMetadata.set("https://downloads.betterthanadventure.net/bta-client/${libs.versions.btaChannel.get()}/v${libs.versions.bta.get()}/manifest.json")
+    runs {
+        prismAccountsFile.orNull?.let { file ->
+            val account: Provider<Account> = providers.fileContents(layout.file(providers.provider { file }))
+                .asText
+                .map { jsonStr ->
+                    val accountNumber = (providers.gradleProperty("prism.accounts.number").orNull?.toInt() ?: 1) - 1
+                    val accounts = Gson().fromJson(jsonStr, AccountsJson::class.java).accounts
+                    accounts.getOrNull(accountNumber.coerceIn(0, accounts.size - 1))
+                        ?: error("No PrismLauncher accounts found in ${file.absolutePath}")
+                }
+            register("clientAuth") {
+                inherit(getByName("client"))
+                configName = "Minecraft Client (Auth)"
+                val acc = account.get()
+                programArgs("--username", acc.profile.name, "--uuid", acc.profile.id, "--session", acc.ygg.token)
+            }
+        }
+    }
 }
+
 repositories {
     mavenCentral()
     maven("https://maven.fabricmc.net/") { name = "Fabric" }