Added ability to delete playlists

src/main/java/net/locusworks/discord/eighttrack/listeners/ReactionListener.java

@@ -0,0 +1,139 @@
+/**
+ *
+ * Project: Pseudo-Bot, File: ReactionListener.java
+ *
+ * Copyright 2019 Locusworks LLC.
+ * All rights reserved. Federal copyright law prohibits unauthorized reproduction by
+ * any means and imposes fines up to $25,000 for violation.  No part of this material
+ * may be reproduced, transmitted, transcribed, stored in a retrieval system, copied,
+ * modified, duplicated, adapted or translated into another program language in any
+ * form or by any means, electronic, mechanical, photocopying, recording, or
+ * otherwise, without the prior written permission from Locusworks. Locusworks
+ * affirms that PSEUDO-BOT(R) software and data is subject to United States
+ * Government Purpose Rights.  Contact Locusworks, 1313 Lawnview Drive
+ * Forney TX 75126, (802) 488-0438, for commercial licensing opportunities.
+ *
+ * IN NO EVENT SHALL LOCUSWORKS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL,
+ * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT
+ * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF LOCUSWORKS HAS BEEN
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  NO RESPONSIBILITY IS ASSUMED BY
+ * LOCUSWORKS FOR ITS USE, OR FOR ANY INFRINGEMENTS OF PATENTS OR OTHER RIGHTS OF
+ * THIRD PARTIES RESULTING FROM ITS USE.  LOCUSWORKS SPECIFICALLY DISCLAIMS ANY
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE AND
+ * ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED HEREUNDER IS PROVIDED "AS
+ * IS". LOCUSWORKS HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
+ * ENHANCEMENTS, OR MODIFICATIONS.
+ */
+package net.locusworks.discord.eighttrack.listeners;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Consumer;
+
+import net.dv8tion.jda.api.entities.Message;
+
+public class ReactionListener<T> {
+
+  private final Map<String, Consumer<Message>> reactions;
+  private final long userId;
+  private volatile T data;
+  private Long expiresIn, lastAction;
+  private boolean active;
+
+  public ReactionListener(long userId, T data) {
+    this.data = data;
+    this.userId = userId;
+    reactions = new LinkedHashMap<>();
+    active = true;
+    lastAction = System.currentTimeMillis();
+    expiresIn = TimeUnit.MINUTES.toMillis(5);
+  }
+
+  public boolean isActive() {
+    return active;
+  }
+
+  public void disable() {
+    this.active = false;
+  }
+
+  /**
+   * The time after which this listener expires which is now + specified time
+   * Defaults to now+5min
+   *
+   * @param timeUnit time units
+   * @param time     amount of time units
+   */
+  public void setExpiresIn(TimeUnit timeUnit, long time) {
+    expiresIn = timeUnit.toMillis(time);
+  }
+
+  /**
+   * Check if this listener has specified emote
+   *
+   * @param emote the emote to check for
+   * @return does this listener do anything with this emote?
+   */
+  public boolean hasReaction(String emote) {
+    return reactions.containsKey(emote);
+  }
+
+  /**
+   * React to the reaction :')
+   *
+   * @param emote   the emote used
+   * @param message the message bound to the reaction
+   */
+  public void react(String emote, Message message) {
+    if (hasReaction(emote)) reactions.get(emote).accept(message);
+  }
+
+  public T getData() {
+    return data;
+  }
+
+  public void setData(T data) {
+    this.data = data;
+  }
+
+  /**
+   * Register a consumer for a specified emote
+   * Multiple emote's will result in overriding the old one
+   *
+   * @param emote    the emote to respond to
+   * @param consumer the behaviour when emote is used
+   */
+  public void registerReaction(String emote, Consumer<Message> consumer) {
+    reactions.put(emote, consumer);
+  }
+
+  /**
+   * @return list of all emotes used in this reaction listener
+   */
+  public Set<String> getEmotes() {
+    return reactions.keySet();
+  }
+
+  /**
+   * updates the timestamp when the reaction was last accessed
+   */
+  public void updateLastAction() {
+    lastAction = System.currentTimeMillis();
+  }
+
+  /**
+   * When does this reaction listener expire?
+   *
+   * @return timestamp in millis
+   */
+  public Long getExpiresInTimestamp() {
+    return lastAction + expiresIn;
+  }
+
+  public long getUserId() {
+    return userId;
+  }
+}