feat: add autoposter

src/main/java/org/discordbots/api/client/DiscordBotListAPI.java

@@ -7,7 +7,16 @@
 import java.util.Map;
 import java.util.concurrent.CompletionStage;
 
+import org.apache.logging.log4j.util.BiConsumer;
+import org.apache.logging.log4j.util.Supplier;
+
 public interface DiscordBotListAPI {
+    void startAutoposter(int delayInSeconds, Supplier<Long> statsCallback, BiConsumer<Long, ? super Throwable> postCallback);
+    void startAutoposter(int delayInSeconds, Supplier<Long> statsCallback);
+    void startAutoposter(Supplier<Long> statsCallback, BiConsumer<Long, ? super Throwable> postCallback);
+    void startAutoposter(Supplier<Long> statsCallback);
+
+    void stopAutoposter();
 
     CompletionStage<Void> setStats(int shardId, int shardTotal, int serverCount);
     CompletionStage<Void> setStats(List<Integer> shardServerCounts);

src/main/java/org/discordbots/api/client/impl/DiscordBotListAPIImpl.java

@@ -20,6 +20,14 @@
 import java.util.concurrent.CompletionStage;
 import java.util.stream.Collectors;
 
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.BiConsumer;
+import java.util.function.Supplier;
+
 public class DiscordBotListAPIImpl implements DiscordBotListAPI {
 
     private static final HttpUrl baseUrl = new HttpUrl.Builder()
@@ -33,6 +41,10 @@ public class DiscordBotListAPIImpl implements DiscordBotListAPI {
 
     private final String token, botId;
 
+    private final ScheduledExecutorService autoposterScheduler;
+    private ScheduledFuture<?> autoposterFuture;
+    private final AtomicBoolean isAutoposterCancelled;
+
     public DiscordBotListAPIImpl(String token, String botId) {
         this.token = token;
         this.botId = botId;
@@ -49,6 +61,65 @@ public DiscordBotListAPIImpl(String token, String botId) {
                     return chain.proceed(req);
                 })
                 .build();
+
+        this.autoposterScheduler = Executors.newSingleThreadScheduledExecutor();
+        this.autoposterFuture = null;
+        this.isAutoposterCancelled = new AtomicBoolean(false);
+    }
+
+    @Override
+    public void startAutoposter(int delayInSeconds, Supplier<Long> statsCallback, BiConsumer<Long, ? super Throwable> postCallback) {
+        if (this.autoposterFuture != null && !this.autoposterFuture.isCancelled()) {
+            return;
+        }
+
+        if (delayInSeconds < 900) {
+            delayInSeconds = 900;
+        }
+
+        this.autoposterFuture = this.autoposterScheduler.scheduleAtFixedRate(() -> {
+            if (!this.isAutoposterCancelled.get()) {
+                final long serverCount = statsCallback.get();
+                final CompletionStage<Void> response = this.setStats(serverCount);
+
+                if (postCallback != null) {
+                    response.whenComplete((_, error) -> {
+                        if (error == null) {
+                            postCallback.accept(serverCount, null);
+                        } else {
+                            postCallback.accept(null, error);
+                            this.stopAutoposter();
+                        }
+                    });
+                }
+            }
+        }, 0, delayInSeconds, TimeUnit.SECONDS);
+    }
+
+    @Override
+    public void startAutoposter(int delayInSeconds, Supplier<Long> statsCallback) {
+        this.startAutoposter(delayInSeconds, statsCallback, null);
+    }
+
+    @Override
+    public void startAutoposter(Supplier<Long> statsCallback, BiConsumer<Long, ? super Throwable> postCallback) {
+        this.startAutoposter(900, statsCallback, postCallback);
+    }
+
+    @Override
+    public void startAutoposter(Supplier<Long> statsCallback) {
+        this.startAutoposter(900, statsCallback, null);
+    }
+
+    @Override
+    public void stopAutoposter() {
+        this.isAutoposterCancelled.set(true);
+
+        if (this.autoposterFuture != null) {
+            this.autoposterFuture.cancel(false);
+        }
+
+        this.autoposterScheduler.shutdownNow();
     }
 
     public CompletionStage<Void> setStats(int shardId, int shardTotal, int serverCount) {