From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Fri, 9 Jul 2021 13:50:48 -0700
Subject: [PATCH] Fix commands from signs not firing command events

This patch changes sign command logic so that `run_command` click events:
  - are logged to the console
  - fire PlayerCommandPreprocessEvent
  - work with double-slash commands like `//wand`
  - sends failure messages to the player who clicked the sign

diff --git a/src/main/java/io/papermc/paper/commands/DelegatingCommandSource.java b/src/main/java/io/papermc/paper/commands/DelegatingCommandSource.java
new file mode 100644
index 0000000000000000000000000000000000000000..01a2bc1feec808790bb93618ce46adb9bea5a9c8
--- /dev/null
+++ b/src/main/java/io/papermc/paper/commands/DelegatingCommandSource.java
@@ -0,0 +1,42 @@
+package io.papermc.paper.commands;
+
+import net.minecraft.commands.CommandSource;
+import net.minecraft.commands.CommandSourceStack;
+import net.minecraft.network.chat.Component;
+import org.bukkit.command.CommandSender;
+
+import java.util.UUID;
+
+public class DelegatingCommandSource implements CommandSource {
+
+    private final CommandSource delegate;
+
+    public DelegatingCommandSource(CommandSource delegate) {
+        this.delegate = delegate;
+    }
+
+    @Override
+    public void sendSystemMessage(Component message) {
+        delegate.sendSystemMessage(message);
+    }
+
+    @Override
+    public boolean acceptsSuccess() {
+        return delegate.acceptsSuccess();
+    }
+
+    @Override
+    public boolean acceptsFailure() {
+        return delegate.acceptsFailure();
+    }
+
+    @Override
+    public boolean shouldInformAdmins() {
+        return delegate.shouldInformAdmins();
+    }
+
+    @Override
+    public CommandSender getBukkitSender(CommandSourceStack wrapper) {
+        return delegate.getBukkitSender(wrapper);
+    }
+}
diff --git a/src/main/java/net/minecraft/world/level/block/entity/SignBlockEntity.java b/src/main/java/net/minecraft/world/level/block/entity/SignBlockEntity.java
index ddf101fd613c854f77971d97a5b0f9319f21242a..a55a2db66d8c8482c5b4107b21bb82d7e8ff4288 100644
--- a/src/main/java/net/minecraft/world/level/block/entity/SignBlockEntity.java
+++ b/src/main/java/net/minecraft/world/level/block/entity/SignBlockEntity.java
@@ -274,7 +274,17 @@ public class SignBlockEntity extends BlockEntity implements CommandSource { // C
             ClickEvent chatclickable = chatmodifier.getClickEvent();
 
             if (chatclickable != null && chatclickable.getAction() == ClickEvent.Action.RUN_COMMAND) {
-                player.getServer().getCommands().performPrefixedCommand(this.createCommandSourceStack(player, world, pos), chatclickable.getValue());
+                // Paper start - Fix commands from signs not firing command events
+                String command = chatclickable.getValue().startsWith("/") ? chatclickable.getValue() : "/" + chatclickable.getValue();
+                if (org.spigotmc.SpigotConfig.logCommands)  {
+                    LOGGER.info("{} issued server command: {}", player.getScoreboardName(), command);
+                }
+                io.papermc.paper.event.player.PlayerSignCommandPreprocessEvent event = new io.papermc.paper.event.player.PlayerSignCommandPreprocessEvent((org.bukkit.entity.Player) player.getBukkitEntity(), command, new org.bukkit.craftbukkit.util.LazyPlayerSet(player.getServer()), (org.bukkit.block.Sign) CraftBlock.at(this.level, this.worldPosition).getState(), front ? Side.FRONT : Side.BACK);
+                if (!event.callEvent()) {
+                    return false;
+                }
+                player.getServer().getCommands().performPrefixedCommand(this.createCommandSourceStack(((org.bukkit.craftbukkit.entity.CraftPlayer) event.getPlayer()).getHandle(), world, pos), event.getMessage());
+                // Paper end - Fix commands from signs not firing command events
                 flag1 = true;
             }
         }
@@ -311,8 +321,23 @@ public class SignBlockEntity extends BlockEntity implements CommandSource { // C
         String s = player == null ? "Sign" : player.getName().getString();
         Object object = player == null ? Component.literal("Sign") : player.getDisplayName();
 
+        // Paper start - Fix commands from signs not firing command events
+        CommandSource commandSource = this.level.paperConfig().misc.showSignClickCommandFailureMsgsToPlayer ? new io.papermc.paper.commands.DelegatingCommandSource(this) {
+            @Override
+            public void sendSystemMessage(Component message) {
+                if (player != null) {
+                    player.sendSystemMessage(message);
+                }
+            }
+
+            @Override
+            public boolean acceptsFailure() {
+                return true;
+            }
+        } : this;
+        // Paper end - Fix commands from signs not firing command events
         // CraftBukkit - this
-        return new CommandSourceStack(this, Vec3.atCenterOf(pos), Vec2.ZERO, (ServerLevel) world, 2, s, (Component) object, world.getServer(), player);
+        return new CommandSourceStack(commandSource, Vec3.atCenterOf(pos), Vec2.ZERO, (ServerLevel) world, 2, s, (Component) object, world.getServer(), player); // Paper - Fix commands from signs not firing command events
     }
 
     @Override
diff --git a/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java b/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
index d113e54a30db16e2ad955170df6030d15de530d6..21b6f90cf5bd7087d1a0f512289d971f2c3e1afa 100644
--- a/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
+++ b/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
@@ -61,7 +61,7 @@ public class BukkitCommandWrapper implements com.mojang.brigadier.Command<Comman
         CommandSender sender = context.getSource().getBukkitSender();
 
         try {
-            return this.server.dispatchCommand(sender, context.getInput()) ? 1 : 0;
+            return this.server.dispatchCommand(sender, context.getRange().get(context.getInput())) ? 1 : 0; // Paper - Fix commands from signs not firing command events; actually use the StringRange from context
         } catch (CommandException ex) {
             sender.sendMessage(org.bukkit.ChatColor.RED + "An internal error occurred while attempting to perform this command");
             this.server.getLogger().log(Level.SEVERE, null, ex);