[Bleeding] Moved DefaultHelpTopic and GenericCommandHelpTopic to public bukkit api.

By: rmichela <deltahat@gmail.com>

paper-api/src/main/java/org/bukkit/help/GenericCommandHelpTopic.java

@@ -0,0 +1,75 @@
+package org.bukkit.help;
+
+import org.bukkit.ChatColor;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.apache.commons.lang.StringUtils;
+import org.bukkit.command.ConsoleCommandSender;
+import org.bukkit.command.PluginCommand;
+import org.bukkit.command.defaults.VanillaCommand;
+import org.bukkit.help.HelpTopic;
+
+/**
+ * Lacking an alternative, the help system will create instances of GenericCommandHelpTopic for each command in the
+ * server's CommandMap. You can use this class as a base class for custom help topics, or as an example for how to
+ * write your own.
+ */
+public class GenericCommandHelpTopic extends HelpTopic {
+
+    private Command command;
+
+    public GenericCommandHelpTopic(Command command) {
+        this.command = command;
+
+        if (command.getLabel().startsWith("/")) {
+            name = command.getLabel();
+        } else {
+            name = "/" + command.getLabel();
+        }
+
+        // The short text is the first line of the description
+        int i = command.getDescription().indexOf("\n");
+        if (i > 1) {
+            shortText = command.getDescription().substring(0, i - 1);
+        } else {
+            shortText = command.getDescription();
+        }
+
+        // Build full text
+        StringBuffer sb = new StringBuffer();
+
+        sb.append(ChatColor.GOLD);
+        sb.append("Description: ");
+        sb.append(ChatColor.WHITE);
+        sb.append(command.getDescription());
+
+        sb.append("\n");
+
+        sb.append(ChatColor.GOLD);
+        sb.append("Usage: ");
+        sb.append(ChatColor.WHITE);
+        sb.append(command.getUsage().replace("<command>", name.substring(1)));
+
+        if (command.getAliases().size() > 0) {
+            sb.append("\n");
+            sb.append(ChatColor.GOLD);
+            sb.append("Aliases: ");
+            sb.append(ChatColor.WHITE);
+            sb.append(ChatColor.WHITE + StringUtils.join(command.getAliases(), ", "));
+        }
+        fullText = sb.toString();
+    }
+
+    public boolean canSee(CommandSender sender) {
+        if (!command.isRegistered() && !(command instanceof VanillaCommand)) {
+            // Unregistered commands should not show up in the help (ignore VanillaCommands)
+            return false;
+        }
+
+        if (sender instanceof ConsoleCommandSender) {
+            return true;
+        }
+
+        return command.testPermissionSilent(sender);
+    }
+}

paper-api/src/main/java/org/bukkit/help/HelpMap.java

@@ -42,5 +42,5 @@ public interface HelpMap {
      * @param factory The {@link HelpTopicFactory} implementation to associate with the {@code commandClass}.
      * @throws IllegalArgumentException Thrown if {@code commandClass} does not derive from a legal base class.
      */
-    public void registerHelpTopicFactory(Class commandClass, HelpTopicFactory factory);
+    public void registerHelpTopicFactory(Class<?> commandClass, HelpTopicFactory<?> factory);
 }

paper-api/src/main/java/org/bukkit/help/IndexHelpTopic.java

@@ -0,0 +1,63 @@
+package org.bukkit.help;
+
+import org.bukkit.ChatColor;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Player;
+import org.bukkit.help.HelpTopic;
+import org.bukkit.util.ChatPaginator;
+
+import java.util.Collection;
+
+/**
+ * This help topic generates a list of other help topics. This class is useful for adding your own
+ * index help topics.
+ */
+public class IndexHelpTopic extends HelpTopic {
+
+    private Collection<HelpTopic> allTopics;
+
+    /**
+     * Creates an index help topic from a collection of help topics. The index is displayed in the order of the
+     * topic collection's iterator. To enforce a particular order, use a sorted collection.
+     * @param topics The collection of topics to use display in an index.
+     */
+    public IndexHelpTopic(Collection<HelpTopic> topics) {
+        this.allTopics = topics;
+    }
+
+    public boolean canSee(CommandSender sender) {
+        return true;
+    }
+
+    public String getName() {
+        return "Overall";
+    }
+
+    public String getShortText() {
+        return "";
+    }
+
+    public String getFullText(CommandSender sender) {
+        StringBuilder sb = new StringBuilder();
+        for (HelpTopic topic : allTopics) {
+            if (topic.canSee(sender)) {
+                StringBuilder line = new StringBuilder();
+                line.append(ChatColor.GOLD);
+                line.append(topic.getName());
+                line.append(": ");
+                line.append(ChatColor.WHITE);
+                line.append(topic.getShortText());
+
+                String lineStr = line.toString().replace("\n", ". ");
+                if (sender instanceof Player && lineStr.length() > ChatPaginator.AVERAGE_CHAT_PAGE_WIDTH) {
+                    sb.append(lineStr.substring(0, ChatPaginator.AVERAGE_CHAT_PAGE_WIDTH - 3));
+                    sb.append("...");
+                } else {
+                    sb.append(lineStr);
+                }
+                sb.append("\n");
+            }
+        }
+        return sb.toString();
+    }
+}