Add hotswap agent support (#910)

Added hotswap detection and reloading all listeners on hotswap. #910

3 files changed, 85 insertions, 0 deletions

diff --git a/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupport.kt b/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupport.kt
new file mode 100644
index 000000000..87acab62d
--- /dev/null
+++ b/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupport.kt
@@ -0,0 +1,22 @@
+package at.hannibal2.skyhanni.test.hotswap
+
+import java.util.function.Supplier
+
+object HotswapSupport {
+    private val isForgeSidePresent =
+        runCatching { Class.forName("moe.nea.hotswapagentforge.forge.HotswapEvent") }.isSuccess
+    private val obj = if (isForgeSidePresent) {
+        Supplier<HotswapSupportHandle?> { HotswapSupportImpl() }
+    } else {
+        Supplier<HotswapSupportHandle?> { null }
+    }.get()
+
+    fun isLoaded(): Boolean {
+        return obj?.isLoaded() ?: false
+    }
+
+    fun load() {
+        obj?.load()
+    }
+}
+
diff --git a/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupportHandle.kt b/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupportHandle.kt
new file mode 100644
index 000000000..c006753a0
--- /dev/null
+++ b/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupportHandle.kt
@@ -0,0 +1,6 @@
+package at.hannibal2.skyhanni.test.hotswap
+
+interface HotswapSupportHandle {
+    fun load()
+    fun isLoaded(): Boolean
+}
diff --git a/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupportImpl.kt b/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupportImpl.kt
new file mode 100644
index 000000000..df74eedbb
--- /dev/null
+++ b/src/main/java/at/hannibal2/skyhanni/test/hotswap/HotswapSupportImpl.kt
@@ -0,0 +1,57 @@
+package at.hannibal2.skyhanni.test.hotswap
+
+import at.hannibal2.skyhanni.SkyHanniMod
+import at.hannibal2.skyhanni.utils.LorenzUtils
+import at.hannibal2.skyhanni.utils.LorenzUtils.makeAccessible
+import at.hannibal2.skyhanni.utils.LorenzUtils.removeFinal
+import moe.nea.hotswapagentforge.forge.ClassDefinitionEvent
+import moe.nea.hotswapagentforge.forge.HotswapEvent
+import moe.nea.hotswapagentforge.forge.HotswapFinishedEvent
+import net.minecraft.client.Minecraft
+import net.minecraftforge.common.MinecraftForge
+import net.minecraftforge.fml.common.eventhandler.SubscribeEvent
+
+class HotswapSupportImpl : HotswapSupportHandle {
+    override fun load() {
+        MinecraftForge.EVENT_BUS.register(this)
+        println("Hotswap Client in Skyhanni loaded")
+    }
+
+    @SubscribeEvent
+    fun onHotswapClass(event: ClassDefinitionEvent.Redefinition) {
+        val instance = SkyHanniMod.modules.find { it.javaClass.name == event.fullyQualifiedName }
+        if (instance == null) return
+        val primaryConstructor = runCatching { instance.javaClass.getDeclaredConstructor() }.getOrNull()
+        Minecraft.getMinecraft().addScheduledTask(Runnable {
+            LorenzUtils.chat("Refreshing event subscriptions for module $instance!")
+            MinecraftForge.EVENT_BUS.unregister(instance)
+            if (primaryConstructor == null) {
+                MinecraftForge.EVENT_BUS.register(instance)
+            } else {
+                SkyHanniMod.modules.remove(instance)
+                primaryConstructor.isAccessible = true
+                val newInstance = primaryConstructor.newInstance()
+                LorenzUtils.chat("Reconstructing $instance -> $newInstance!")
+                val instanceField = runCatching { instance.javaClass.getDeclaredField("INSTANCE") }.getOrNull()
+                    ?.takeIf { it.type == instance.javaClass }
+                    ?.makeAccessible()
+                    ?.removeFinal()
+                if (instanceField != null) {
+                    LorenzUtils.chat("Reinjected static instance $newInstance!")
+                    instanceField.set(null, newInstance)
+                }
+                SkyHanniMod.modules.add(newInstance)
+                MinecraftForge.EVENT_BUS.register(newInstance)
+            }
+        })
+    }
+
+    @SubscribeEvent
+    fun onHotswapDetected(event: HotswapFinishedEvent) {
+        LorenzUtils.chat("Hotswap finished!")
+    }
+
+    override fun isLoaded(): Boolean {
+        return HotswapEvent.isReady()
+    }
+}