Publish Fabric jars to CF/Modrinth

Like all publishing code, we'll only find out if it works when we run
it!

buildSrc/src/main/kotlin/cc-tweaked.mod-publishing.gradle.kts

@@ -0,0 +1,59 @@
+// SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+import net.darkhax.curseforgegradle.TaskPublishCurseForge
+import cc.tweaked.gradle.setProvider
+
+plugins {
+    id("net.darkhax.curseforgegradle")
+    id("com.modrinth.minotaur")
+    id("cc-tweaked.publishing")
+}
+
+abstract class ModPublishingExtension {
+    abstract val output: Property<AbstractArchiveTask>
+
+    init {
+        output.finalizeValueOnRead()
+    }
+}
+
+val modPublishing = project.extensions.create("modPublishing", ModPublishingExtension::class.java)
+
+val isUnstable = project.properties["isUnstable"] == "true"
+val modVersion: String by extra
+val mcVersion: String by extra
+
+val publishCurseForge by tasks.registering(TaskPublishCurseForge::class) {
+    group = PublishingPlugin.PUBLISH_TASK_GROUP
+    description = "Upload artifacts to CurseForge"
+
+    apiToken = findProperty("curseForgeApiKey") ?: ""
+    enabled = apiToken != ""
+
+    val mainFile = upload("282001", modPublishing.output.get().archiveFile)
+    dependsOn(modPublishing.output) // See https://github.com/Darkhax/CurseForgeGradle/pull/7.
+    mainFile.changelog =
+        "Release notes can be found on the [GitHub repository](https://github.com/cc-tweaked/CC-Tweaked/releases/tag/v$mcVersion-$modVersion)."
+    mainFile.changelogType = "markdown"
+    mainFile.releaseType = if (isUnstable) "alpha" else "release"
+    mainFile.gameVersions.add(mcVersion)
+}
+
+tasks.publish { dependsOn(publishCurseForge) }
+
+modrinth {
+    token.set(findProperty("modrinthApiKey") as String? ?: "")
+    projectId.set("gu7yAYhd")
+    versionNumber.set("$mcVersion-$modVersion")
+    versionName.set(modVersion)
+    versionType.set(if (isUnstable) "alpha" else "release")
+    uploadFile.setProvider(modPublishing.output)
+    gameVersions.add(mcVersion)
+    changelog.set("Release notes can be found on the [GitHub repository](https://github.com/cc-tweaked/CC-Tweaked/releases/tag/v$mcVersion-$modVersion).")
+
+    syncBodyFrom.set(provider { file("doc/mod-page.md").readText() })
+}
+
+tasks.publish { dependsOn(tasks.modrinth) }

buildSrc/src/main/kotlin/cc/tweaked/gradle/Extensions.kt

@@ -5,6 +5,8 @@
 package cc.tweaked.gradle
 
 import org.gradle.api.artifacts.dsl.DependencyHandler
+import org.gradle.api.provider.Property
+import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.JavaExec
 import org.gradle.process.BaseExecSpec
 import org.gradle.process.JavaExecSpec
@@ -119,3 +121,6 @@ class CloseScope : AutoCloseable {
         }
     }
 }
+
+/** Proxy method to avoid overload ambiguity. */
+fun <T> Property<T>.setProvider(provider: Provider<out T>) = set(provider)