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/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
index feaabc6d65845b81a3a184dc332d115200bdcca3..3a83320bae86ba1acb189b9b2cf934ad0393c353 100644
--- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
@@ -863,4 +863,9 @@ public class PaperWorldConfig {
     private void fixInvulnerableEndCrystalExploit() {
         fixInvulnerableEndCrystalExploit = getBoolean("unsupported-settings.fix-invulnerable-end-crystal-exploit", fixInvulnerableEndCrystalExploit);
     }
+
+    public boolean showSignClickCommandFailureMessagesToPlayer = false;
+    private void showSignClickCommandFailureMessagesToPlayer() {
+        showSignClickCommandFailureMessagesToPlayer = getBoolean("show-sign-click-command-failure-msgs-to-player", showSignClickCommandFailureMessagesToPlayer);
+    }
 }
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..1f6747d7a4c33f0ee7b0dc2120081bb87a855d35
--- /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 sendMessage(Component message, UUID sender) {
+        delegate.sendMessage(message, sender);
+    }
+
+    @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 615c4f9d9841f7ddc3e5c854e90f41c3905c2e8f..6371176fba41218a209ea59b4cafe5b2d4a685fd 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
@@ -40,6 +40,7 @@ public class SignBlockEntity extends BlockEntity implements CommandSource { // C
     private boolean renderMessagedFiltered;
     private DyeColor color;
     private boolean hasGlowingText;
+    private static final org.apache.logging.log4j.Logger LOGGER = org.apache.logging.log4j.LogManager.getLogger();
 
     public SignBlockEntity(BlockPos pos, BlockState state) {
         super(BlockEntityType.SIGN, pos, state);
@@ -224,7 +225,17 @@ public class SignBlockEntity extends BlockEntity implements CommandSource { // C
             ClickEvent chatclickable = chatmodifier.getClickEvent();
 
             if (chatclickable != null && chatclickable.getAction() == ClickEvent.Action.RUN_COMMAND) {
-                player.getServer().getCommands().performCommand(this.createCommandSourceStack(player), chatclickable.getValue());
+                // Paper start
+                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(player.getBukkitEntity(), command, new org.bukkit.craftbukkit.util.LazyPlayerSet(player.getServer()), (org.bukkit.block.Sign) net.minecraft.server.MCUtil.toBukkitBlock(this.level, this.worldPosition).getState());
+                if (!event.callEvent()) {
+                    return false;
+                }
+                player.getServer().getCommands().performCommand(this.createCommandSourceStack(((org.bukkit.craftbukkit.entity.CraftPlayer) event.getPlayer()).getHandle()), event.getMessage());
+                // Paper end
             }
         }
 
@@ -260,8 +271,21 @@ public class SignBlockEntity extends BlockEntity implements CommandSource { // C
         String s = player == null ? "Sign" : player.getName().getString();
         Object object = player == null ? new TextComponent("Sign") : player.getDisplayName();
 
+        // Paper start - send messages back to the player
+        CommandSource commandSource = this.level.paperConfig.showSignClickCommandFailureMessagesToPlayer ? new io.papermc.paper.commands.DelegatingCommandSource(this) {
+            @Override
+            public void sendMessage(Component message, UUID sender) {
+                player.sendMessage(message, sender);
+            }
+
+            @Override
+            public boolean acceptsFailure() {
+                return true;
+            }
+        } : this;
+        // Paper end
         // CraftBukkit - this
-        return new CommandSourceStack(this, Vec3.atCenterOf(this.worldPosition), Vec2.ZERO, (ServerLevel) this.level, 2, s, (Component) object, this.level.getServer(), player);
+        return new CommandSourceStack(commandSource, Vec3.atCenterOf(this.worldPosition), Vec2.ZERO, (ServerLevel) this.level, 2, s, (Component) object, this.level.getServer(), player); // Paper
     }
 
     public DyeColor getColor() {
diff --git a/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java b/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
index 0bba36d18d56a4dc2d6c6fb7969e5e6f0e1da404..a246a0bd9e57fb0703ba756e8aa1109f1674c0e8 100644
--- a/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
+++ b/src/main/java/org/bukkit/craftbukkit/command/BukkitCommandWrapper.java
@@ -50,7 +50,7 @@ public class BukkitCommandWrapper implements com.mojang.brigadier.Command<Comman
 
     @Override
     public int run(CommandContext<CommandSourceStack> context) throws CommandSyntaxException {
-        return this.server.dispatchCommand(context.getSource().getBukkitSender(), context.getInput()) ? 1 : 0;
+        return this.server.dispatchCommand(context.getSource().getBukkitSender(), context.getRange().get(context.getInput())) ? 1 : 0; // Paper - actually use the StringRange from context
     }
 
     @Override