(plugin) Add native event stream

plugin/android/src/main/kotlin/com/nkming/nc_photos/plugin/NativeEventChannelHandler.kt

@@ -0,0 +1,52 @@
+package com.nkming.nc_photos.plugin
+
+import io.flutter.plugin.common.EventChannel
+import io.flutter.plugin.common.MethodCall
+import io.flutter.plugin.common.MethodChannel
+
+class NativeEventChannelHandler : MethodChannel.MethodCallHandler,
+	EventChannel.StreamHandler {
+	companion object {
+		const val EVENT_CHANNEL = "${K.LIB_ID}/native_event"
+		const val METHOD_CHANNEL = "${K.LIB_ID}/native_event_method"
+
+		private val eventSinks = mutableMapOf<Int, EventChannel.EventSink>()
+		private var nextId = 0
+	}
+
+	override fun onMethodCall(call: MethodCall, result: MethodChannel.Result) {
+		when (call.method) {
+			"fire" -> {
+				try {
+					fire(
+						call.argument("event")!!, call.argument("data"), result
+					)
+				} catch (e: Throwable) {
+					result.error("systemException", e.toString(), null)
+				}
+			}
+		}
+	}
+
+	override fun onListen(arguments: Any?, events: EventChannel.EventSink) {
+		eventSinks[id] = events
+	}
+
+	override fun onCancel(arguments: Any?) {
+		eventSinks.remove(id)
+	}
+
+	private fun fire(
+		event: String, data: String?, result: MethodChannel.Result
+	) {
+		for (s in eventSinks.values) {
+			s.success(buildMap {
+				put("event", event)
+				if (data != null) put("data", data)
+			})
+		}
+		result.success(null)
+	}
+
+	private val id = nextId++
+}

plugin/android/src/main/kotlin/com/nkming/nc_photos/plugin/NcPhotosPlugin.kt

@@ -2,12 +2,14 @@ package com.nkming.nc_photos.plugin
 
 import androidx.annotation.NonNull
 import io.flutter.embedding.engine.plugins.FlutterPlugin
+import io.flutter.plugin.common.EventChannel
 import io.flutter.plugin.common.MethodChannel
 
 class NcPhotosPlugin : FlutterPlugin {
 	override fun onAttachedToEngine(
 		@NonNull flutterPluginBinding: FlutterPlugin.FlutterPluginBinding
 	) {
+		// this may get called more than once
 		lockChannel = MethodChannel(
 			flutterPluginBinding.binaryMessenger, LockChannelHandler.CHANNEL
 		)
@@ -22,6 +24,18 @@ class NcPhotosPlugin : FlutterPlugin {
 				flutterPluginBinding.applicationContext
 			)
 		)
+
+		val nativeEventHandler = NativeEventChannelHandler()
+		nativeEventChannel = EventChannel(
+			flutterPluginBinding.binaryMessenger,
+			NativeEventChannelHandler.EVENT_CHANNEL
+		)
+		nativeEventChannel.setStreamHandler(nativeEventHandler)
+		nativeEventMethodChannel = MethodChannel(
+			flutterPluginBinding.binaryMessenger,
+			NativeEventChannelHandler.METHOD_CHANNEL
+		)
+		nativeEventMethodChannel.setMethodCallHandler(nativeEventHandler)
 	}
 
 	override fun onDetachedFromEngine(
@@ -29,8 +43,12 @@ class NcPhotosPlugin : FlutterPlugin {
 	) {
 		lockChannel.setMethodCallHandler(null)
 		notificationChannel.setMethodCallHandler(null)
+		nativeEventChannel.setStreamHandler(null)
+		nativeEventMethodChannel.setMethodCallHandler(null)
 	}
 
 	private lateinit var lockChannel: MethodChannel
 	private lateinit var notificationChannel: MethodChannel
+	private lateinit var nativeEventChannel: EventChannel
+	private lateinit var nativeEventMethodChannel: MethodChannel
 }

plugin/lib/nc_photos_plugin.dart

@@ -1,4 +1,5 @@
 library nc_photos_plugin;
 
 export 'src/lock.dart';
+export 'src/native_event.dart';
 export 'src/notification.dart';

plugin/lib/src/native_event.dart

@@ -0,0 +1,34 @@
+import 'dart:async';
+
+import 'package:flutter/services.dart';
+import 'package:nc_photos_plugin/src/k.dart' as k;
+
+class NativeEventObject {
+  NativeEventObject(this.event, this.data);
+
+  final String event;
+  final String? data;
+}
+
+class NativeEvent {
+  static Future<void> fire(NativeEventObject ev) =>
+      _methodChannel.invokeMethod("fire", <String, dynamic>{
+        "event": ev.event,
+        if (ev.data != null) "data": ev.data,
+      });
+
+  static Stream get stream => _eventStream;
+
+  static const _eventChannel = EventChannel("${k.libId}/native_event");
+  static const _methodChannel = MethodChannel("${k.libId}/native_event_method");
+
+  static late final _eventStream = _eventChannel
+      .receiveBroadcastStream()
+      .map((event) {
+        if (event is Map) {
+          return NativeEventObject(event["event"], event["data"]);
+        } else {
+          return event;
+        }
+      });
+}