1 files changed, 53 insertions, 0 deletions
diff --git a/src/main/kotlin/io/dico/parcels2/util/FunctionHelper.kt b/src/main/kotlin/io/dico/parcels2/util/FunctionHelper.kt
new file mode 100644
index 0000000..ea16652
--- /dev/null
+++ b/src/main/kotlin/io/dico/parcels2/util/FunctionHelper.kt
@@ -0,0 +1,53 @@
+package io.dico.parcels2.util
+
+import io.dico.parcels2.ParcelsPlugin
+import kotlinx.coroutines.experimental.*
+import org.bukkit.scheduler.BukkitTask
+import kotlin.coroutines.experimental.CoroutineContext
+
+@Suppress("NOTHING_TO_INLINE")
+class FunctionHelper(val plugin: ParcelsPlugin) {
+    val mainThreadDispatcher: MainThreadDispatcher = MainThreadDispatcherImpl()
+
+    fun <T> deferLazilyOnMainThread(block: suspend CoroutineScope.() -> T): Deferred<T> {
+        return async(context = mainThreadDispatcher, start = CoroutineStart.LAZY, block = block)
+    }
+
+    fun <T> deferUndispatchedOnMainThread(block: suspend CoroutineScope.() -> T): Deferred<T> {
+        return async(context = mainThreadDispatcher, start = CoroutineStart.UNDISPATCHED, block = block)
+    }
+
+    fun launchLazilyOnMainThread(block: suspend CoroutineScope.() -> Unit): Job {
+        return launch(context = mainThreadDispatcher, start = CoroutineStart.LAZY, block = block)
+    }
+
+    inline fun schedule(noinline task: () -> Unit) = schedule(0, task)
+
+    fun schedule(delay: Int, task: () -> Unit): BukkitTask {
+        return plugin.server.scheduler.runTaskLater(plugin, task, delay.toLong())
+    }
+
+    fun scheduleRepeating(delay: Int, interval: Int, task: () -> Unit): BukkitTask {
+        return plugin.server.scheduler.runTaskTimer(plugin, task, delay.toLong(), interval.toLong())
+    }
+
+    abstract class MainThreadDispatcher : CoroutineDispatcher() {
+        abstract val mainThread: Thread
+        abstract fun runOnMainThread(task: Runnable)
+    }
+
+    private inner class MainThreadDispatcherImpl : MainThreadDispatcher() {
+        override val mainThread: Thread = Thread.currentThread()
+
+        override fun dispatch(context: CoroutineContext, block: Runnable) {
+            runOnMainThread(block)
+        }
+
+        @Suppress("OVERRIDE_BY_INLINE")
+        override inline fun runOnMainThread(task: Runnable) {
+            if (Thread.currentThread() === mainThread) task.run()
+            else plugin.server.scheduler.runTaskLater(plugin, task, 0)
+        }
+    }
+
+}