implement waiting

Author: wenxi-zeng

core/src/main/java/com/segment/analytics/kotlin/core/Waiting.kt

@@ -0,0 +1,60 @@
+package com.segment.analytics.kotlin.core
+
+import com.segment.analytics.kotlin.core.platform.Plugin
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+
+/**
+ * An interface that provides functionality of pausing and resuming event processing on Analytics.
+ *
+ * By default plugins that implement this interface pauses processing when it is added to
+ * analytics (via `setup()`) and resumes after 30s.
+ *
+ * To customize pausing and resuming, override `setup()` and call `pause()/resumes()` as needed
+ */
+interface WaitingPlugin: Plugin {
+    override fun setup(analytics: Analytics) {
+        super.setup(analytics)
+        pause()
+    }
+
+    fun pause() {
+        analytics.pauseEventProcessing(this)
+    }
+
+    fun resume() {
+        analytics.resumeEventProcessing(this)
+    }
+}
+
+fun Analytics.pauseEventProcessing(plugin: WaitingPlugin) = analyticsScope.launch {
+    store.dispatch(System.AddWaitingPlugin(plugin.hashCode()), System::class)
+}
+
+
+fun Analytics.resumeEventProcessing(plugin: WaitingPlugin) = analyticsScope.launch {
+    store.dispatch(System.RemoveWaitingPlugin(plugin.hashCode()), System::class)
+}
+
+internal suspend fun Analytics.running(): Boolean {
+    val system = store.currentState(System::class)
+    return system?.running ?: false
+}
+
+internal suspend fun Analytics.pauseEventProcessing() {
+    if (!running()) return
+
+    store.dispatch(System.ToggleRunningAction(false), System::class)
+    startProcessingAfterTimeout()
+}
+
+internal suspend fun Analytics.resumeEventProcessing() {
+    if (running()) return
+    store.dispatch(System.ToggleRunningAction(true), System::class)
+}
+
+internal fun Analytics.startProcessingAfterTimeout() = analyticsScope.launch {
+    delay(30_000)
+    store.dispatch(System.ForceRunningAction(), System::class)
+}
+