Add discord webhooks

lib/structs/discordHookHelper.dart

@@ -0,0 +1,57 @@
+import 'dart:convert';
+
+import 'package:dio/dio.dart';
+import 'package:libac_dart/nbt/impl/CompoundTag.dart';
+import 'package:libac_dart/nbt/impl/StringTag.dart';
+
+class DiscordHookHelper {
+  static Future<void> sendWebHook(DiscordHookProps? props, int colorCode,
+      String title, String content) async {
+    if (props == null) return; // The webhook setting is not yet set up
+    var js = json.encode({
+      "content": "",
+      "embeds": [
+        {
+          "title": title,
+          "description": content,
+          "color": colorCode,
+          "author": {"name": props.serverName}
+        }
+      ],
+      "attachments": []
+    });
+
+    Dio dio = Dio();
+    dio.post(props.url, data: js);
+  }
+}
+
+class DiscordHookProps {
+  String url;
+  String serverName;
+
+  DiscordHookProps({required this.url, required this.serverName});
+
+  CompoundTag serialize() {
+    CompoundTag ct = CompoundTag();
+    ct.put(TAG_URL, StringTag.valueOf(url));
+    ct.put(TAG_SERVER_NAME, StringTag.valueOf(serverName));
+
+    return ct;
+  }
+
+  static DiscordHookProps deserialize(CompoundTag ct) {
+    return DiscordHookProps(
+        url: ct.get(TAG_URL)!.asString(),
+        serverName: ct.get(TAG_SERVER_NAME)!.asString());
+  }
+
+  static const String TAG_URL = "url";
+  static const String TAG_SERVER_NAME = "serverName";
+  static const String TAG_NAME = "discord";
+
+  static const int ONLINE_ALERT = 1869056;
+  static const int OFFLINE_ALERT = 8716288;
+  static const int ALERT = 21893; // non-intrusive
+  static const int ALERT_INTRUSIVE = 6291589;
+}