#1170: Add preliminary support for multi sided signs

By: Yannick Lamprecht <yannicklamprecht@live.de>

paper-server/src/main/java/org/bukkit/craftbukkit/block/CraftSign.java

@@ -2,46 +2,40 @@ package org.bukkit.craftbukkit.block;
 
 import com.google.common.base.Preconditions;
 import net.minecraft.network.chat.IChatBaseComponent;
-import net.minecraft.world.item.EnumColor;
 import net.minecraft.world.level.block.entity.TileEntitySign;
 import org.bukkit.DyeColor;
 import org.bukkit.World;
 import org.bukkit.block.Sign;
+import org.bukkit.block.sign.Side;
+import org.bukkit.block.sign.SignSide;
+import org.bukkit.craftbukkit.block.sign.CraftSignSide;
 import org.bukkit.craftbukkit.entity.CraftPlayer;
 import org.bukkit.craftbukkit.util.CraftChatMessage;
 import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
 
 public class CraftSign<T extends TileEntitySign> extends CraftBlockEntityState<T> implements Sign {
 
-    // Lazily initialized only if requested:
-    private String[] originalLines = null;
-    private String[] lines = null;
+    private final CraftSignSide front;
 
     public CraftSign(World world, T tileEntity) {
         super(world, tileEntity);
+        this.front = new CraftSignSide(this.getSnapshot());
     }
 
     @Override
     public String[] getLines() {
-        if (lines == null) {
-            // Lazy initialization:
-            TileEntitySign sign = this.getSnapshot();
-            lines = new String[sign.messages.length];
-            System.arraycopy(revertComponents(sign.messages), 0, lines, 0, lines.length);
-            originalLines = new String[lines.length];
-            System.arraycopy(lines, 0, originalLines, 0, originalLines.length);
-        }
-        return lines;
+        return front.getLines();
     }
 
     @Override
     public String getLine(int index) throws IndexOutOfBoundsException {
-        return getLines()[index];
+        return front.getLine(index);
     }
 
     @Override
     public void setLine(int index, String line) throws IndexOutOfBoundsException {
-        getLines()[index] = line;
+        front.setLine(index, line);
     }
 
     @Override
@@ -56,37 +50,37 @@ public class CraftSign<T extends TileEntitySign> extends CraftBlockEntityState<T
 
     @Override
     public boolean isGlowingText() {
-        return getSnapshot().hasGlowingText();
+        return front.isGlowingText();
     }
 
     @Override
     public void setGlowingText(boolean glowing) {
-        getSnapshot().setHasGlowingText(glowing);
+        front.setGlowingText(glowing);
+    }
+
+    @NotNull
+    @Override
+    public SignSide getSide(Side side) {
+        Preconditions.checkArgument(side != null, "side == null");
+
+        return front;
     }
 
     @Override
     public DyeColor getColor() {
-        return DyeColor.getByWoolData((byte) getSnapshot().getColor().getId());
+        return front.getColor();
     }
 
     @Override
     public void setColor(DyeColor color) {
-        getSnapshot().setColor(EnumColor.byId(color.getWoolData()));
+        front.setColor(color);
     }
 
     @Override
     public void applyTo(T sign) {
-        super.applyTo(sign);
+        front.applyLegacyStringToSignSide();
 
-        if (lines != null) {
-            for (int i = 0; i < lines.length; i++) {
-                String line = (lines[i] == null) ? "" : lines[i];
-                if (line.equals(originalLines[i])) {
-                    continue; // The line contents are still the same, skip.
-                }
-                sign.setMessage(i, CraftChatMessage.fromString(line)[0]);
-            }
-        }
+        super.applyTo(sign);
     }
 
     public static void openSign(Sign sign, Player player) {

paper-server/src/main/java/org/bukkit/craftbukkit/block/sign/CraftSignSide.java

@@ -0,0 +1,79 @@
+package org.bukkit.craftbukkit.block.sign;
+
+import net.minecraft.world.item.EnumColor;
+import net.minecraft.world.level.block.entity.TileEntitySign;
+import org.bukkit.DyeColor;
+import org.bukkit.block.sign.SignSide;
+import org.bukkit.craftbukkit.block.CraftSign;
+import org.bukkit.craftbukkit.util.CraftChatMessage;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class CraftSignSide implements SignSide {
+
+    // Lazily initialized only if requested:
+    private String[] originalLines = null;
+    private String[] lines = null;
+    private final TileEntitySign signText;
+
+    public CraftSignSide(TileEntitySign signText) {
+        this.signText = signText;
+    }
+
+    @NotNull
+    @Override
+    public String[] getLines() {
+        if (lines == null) {
+            // Lazy initialization:
+            lines = new String[signText.messages.length];
+            System.arraycopy(CraftSign.revertComponents(signText.messages), 0, lines, 0, lines.length);
+            originalLines = new String[lines.length];
+            System.arraycopy(lines, 0, originalLines, 0, originalLines.length);
+        }
+        return lines;
+    }
+
+    @NotNull
+    @Override
+    public String getLine(int index) throws IndexOutOfBoundsException {
+        return getLines()[index];
+    }
+
+    @Override
+    public void setLine(int index, @NotNull String line) throws IndexOutOfBoundsException {
+        getLines()[index] = line;
+    }
+
+    @Override
+    public boolean isGlowingText() {
+        return signText.hasGlowingText();
+    }
+
+    @Override
+    public void setGlowingText(boolean glowing) {
+        signText.setHasGlowingText(glowing);
+    }
+
+    @Nullable
+    @Override
+    public DyeColor getColor() {
+        return DyeColor.getByWoolData((byte) signText.getColor().getId());
+    }
+
+    @Override
+    public void setColor(@NotNull DyeColor color) {
+        signText.setColor(EnumColor.byId(color.getWoolData()));
+    }
+
+    public void applyLegacyStringToSignSide() {
+        if (lines != null) {
+            for (int i = 0; i < lines.length; i++) {
+                String line = (lines[i] == null) ? "" : lines[i];
+                if (line.equals(originalLines[i])) {
+                    continue; // The line contents are still the same, skip.
+                }
+                signText.setMessage(i, CraftChatMessage.fromString(line)[0]);
+            }
+        }
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -112,6 +112,7 @@ import org.bukkit.block.Block;
 import org.bukkit.block.BlockState;
 import org.bukkit.block.Sign;
 import org.bukkit.block.data.BlockData;
+import org.bukkit.block.sign.Side;
 import org.bukkit.configuration.serialization.DelegateDeserialization;
 import org.bukkit.conversations.Conversation;
 import org.bukkit.conversations.ConversationAbandonedEvent;
@@ -162,6 +163,7 @@ import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.messaging.StandardMessenger;
 import org.bukkit.profile.PlayerProfile;
 import org.bukkit.scoreboard.Scoreboard;
+import org.jetbrains.annotations.NotNull;
 
 @DelegateDeserialization(CraftOfflinePlayer.class)
 public class CraftPlayer extends CraftHumanEntity implements Player {
@@ -2093,6 +2095,11 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         CraftSign.openSign(sign, this);
     }
 
+    @Override
+    public void openSign(@NotNull Sign sign, @NotNull Side side) {
+        openSign(sign); // todo implement per side
+    }
+
     @Override
     public void showDemoScreen() {
         if (getHandle().connection == null) return;