Support CLIENTTAGDENY isupport value

Author: mbax

src/main/java/org/kitteh/irc/client/library/defaults/element/isupport/DefaultISupportClientTagDeny.java

@@ -0,0 +1,58 @@
+/*
+ * * Copyright (C) 2013-2021 Matt Baxter https://kitteh.org
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.kitteh.irc.client.library.defaults.element.isupport;
+
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+import org.kitteh.irc.client.library.Client;
+import org.kitteh.irc.client.library.defaults.element.DefaultISupportParameter;
+import org.kitteh.irc.client.library.element.ISupportParameter;
+
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Default implementation of {@link ClientTagDeny}.
+ */
+public class DefaultISupportClientTagDeny extends DefaultISupportParameter implements ISupportParameter.ClientTagDeny {
+    private final List<String> list;
+
+    /**
+     * Constructs the object.
+     *
+     * @param client client
+     * @param name parameter name
+     * @param value parameter value, if present
+     */
+    public DefaultISupportClientTagDeny(@NonNull Client client, @NonNull String name, @Nullable String value) {
+        super(client, name, value);
+        this.list = (value == null || value.isEmpty()) ? Collections.emptyList() : Collections.unmodifiableList(Arrays.asList(value.split(",")));
+    }
+
+    @Override
+    public @NonNull List<String> getList() {
+        return this.list;
+    }
+}

src/main/java/org/kitteh/irc/client/library/defaults/feature/DefaultISupportManager.java

@@ -33,6 +33,7 @@
 import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportChanModes;
 import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportChanTypes;
 import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportChannelLen;
+import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportClientTagDeny;
 import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportEList;
 import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportExcepts;
 import org.kitteh.irc.client.library.defaults.element.isupport.DefaultISupportExtBan;
@@ -75,6 +76,7 @@ public DefaultISupportManager(Client.WithManagement client) {
         this.registerParameter(ISupportParameter.ChanLimit.NAME, DefaultISupportChanLimit::new);
         this.registerParameter(ISupportParameter.ChanModes.NAME, DefaultISupportChanModes::new);
         this.registerParameter(ISupportParameter.ChanTypes.NAME, DefaultISupportChanTypes::new);
+        this.registerParameter(ISupportParameter.ClientTagDeny.NAME, DefaultISupportClientTagDeny::new);
         this.registerParameter(ISupportParameter.EList.NAME, DefaultISupportEList::new);
         this.registerParameter(ISupportParameter.Excepts.NAME, DefaultISupportExcepts::new);
         this.registerParameter(ISupportParameter.ExtBan.NAME, DefaultISupportExtBan::new);

src/main/java/org/kitteh/irc/client/library/element/ISupportParameter.java

@@ -150,6 +150,52 @@ interface ChanTypes extends ISupportParameter {
         @NonNull List<Character> getTypes();
     }
 
+    /**
+     * Represents a listing of client tags that will be blocked and dropped
+     */
+    interface ClientTagDeny extends ISupportParameter {
+        String NAME = "CLIENTTAGDENY";
+
+        /**
+         * Gets the list of items provided by the server. An asterisk first
+         * means all client tags are blocked, with the exception of any
+         * subsequent tags listed with a hyphen prefix.
+         *
+         * @return list of returned items, which may be empty
+         */
+        @NonNull List<String> getList();
+
+        /**
+         * Gets if a given client tag is allowed by the server.
+         *
+         * @param tag tag to test
+         * @return true if allowed, false if denied
+         */
+        default boolean isAllowed(@NonNull String tag) {
+            List<String> list = this.getList();
+            if (list.isEmpty()) {
+                return true;
+            }
+            if (list.get(0).equals("*")) {
+                if (list.size() == 1) {
+                    return false;
+                }
+                for (String item : list) {
+                    if (item.charAt(0) == '-' && item.substring(1).equalsIgnoreCase(tag)) {
+                        return true;
+                    }
+                }
+                return false;
+            }
+            for (String item : list) {
+                if (item.equalsIgnoreCase(tag)) {
+                    return false;
+                }
+            }
+            return true;
+        }
+    }
+
     /**
      * Represents the LIST extensions supported.
      */