Expose printout contents to the API

Closes #2099

projects/common-api/src/main/java/dan200/computercraft/api/media/PrintoutContents.java

@@ -0,0 +1,46 @@
+// SPDX-FileCopyrightText: 2025 The CC: Tweaked Developers
+//
+// SPDX-License-Identifier: MPL-2.0
+
+package dan200.computercraft.api.media;
+
+import dan200.computercraft.impl.ComputerCraftAPIService;
+import net.minecraft.world.item.ItemStack;
+
+import javax.annotation.Nullable;
+import java.util.stream.Stream;
+
+/**
+ * The contents of a page (or book) created by a ComputerCraft printer.
+ *
+ * @since 1.115
+ */
+@Nullable
+public interface PrintoutContents {
+    /**
+     * Get the (possibly empty) title for this printout.
+     *
+     * @return The title of this printout.
+     */
+    String getTitle();
+
+    /**
+     * Get the text contents of this printout, as a sequence of lines.
+     * <p>
+     * The lines in the printout may include blank lines at the end of the document, as well as trailing spaces on each
+     * line.
+     *
+     * @return The text contents of this printout.
+     */
+    Stream<String> getTextLines();
+
+    /**
+     * Get the printout contents for a particular stack.
+     *
+     * @param stack The stack to get the contents for.
+     * @return The printout contents, or {@code null} if this is not a printout item.
+     */
+    static @Nullable PrintoutContents get(ItemStack stack) {
+        return ComputerCraftAPIService.get().getPrintoutContents(stack);
+    }
+}

projects/common-api/src/main/java/dan200/computercraft/impl/ComputerCraftAPIService.java

@@ -12,6 +12,7 @@
 import dan200.computercraft.api.lua.GenericSource;
 import dan200.computercraft.api.lua.ILuaAPIFactory;
 import dan200.computercraft.api.media.MediaProvider;
+import dan200.computercraft.api.media.PrintoutContents;
 import dan200.computercraft.api.network.PacketNetwork;
 import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.network.wired.WiredNode;
@@ -75,6 +76,9 @@ static ComputerCraftAPIService get() {
 
     DetailRegistry<BlockReference> getBlockInWorldDetailRegistry();
 
+    @Nullable
+    PrintoutContents getPrintoutContents(ItemStack stack);
+
     final class Instance {
         static final @Nullable ComputerCraftAPIService INSTANCE;
         static final @Nullable Throwable ERROR;

projects/common/src/main/java/dan200/computercraft/impl/AbstractComputerCraftAPI.java

@@ -12,6 +12,7 @@
 import dan200.computercraft.api.lua.GenericSource;
 import dan200.computercraft.api.lua.ILuaAPIFactory;
 import dan200.computercraft.api.media.MediaProvider;
+import dan200.computercraft.api.media.PrintoutContents;
 import dan200.computercraft.api.network.PacketNetwork;
 import dan200.computercraft.api.network.wired.WiredElement;
 import dan200.computercraft.api.network.wired.WiredNode;
@@ -26,6 +27,7 @@
 import dan200.computercraft.shared.computer.core.ServerContext;
 import dan200.computercraft.shared.details.BlockDetails;
 import dan200.computercraft.shared.details.ItemDetails;
+import dan200.computercraft.shared.media.items.PrintoutItem;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.core.Registry;
@@ -39,6 +41,7 @@
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.stream.Stream;
 
 public abstract class AbstractComputerCraftAPI implements ComputerCraftAPIService {
     private final DetailRegistry<ItemStack> itemStackDetails = new DetailRegistryImpl<>(ItemDetails::fillBasic);
@@ -134,4 +137,21 @@ public final DetailRegistry<ItemStack> getItemStackDetailRegistry() {
     public final DetailRegistry<BlockReference> getBlockInWorldDetailRegistry() {
         return blockDetails;
     }
+
+    @Override
+    public @Nullable PrintoutContents getPrintoutContents(ItemStack stack) {
+        return stack.getItem() instanceof PrintoutItem ? new PrintoutContentsImpl(stack) : null;
+    }
+
+    public record PrintoutContentsImpl(ItemStack stack) implements PrintoutContents {
+        @Override
+        public String getTitle() {
+            return PrintoutItem.getTitle(stack);
+        }
+
+        @Override
+        public Stream<String> getTextLines() {
+            return Stream.of(PrintoutItem.getText(stack));
+        }
+    }
 }

projects/core/src/main/java/dan200/computercraft/core/apis/http/websocket/WebsocketHandle.java

@@ -69,7 +69,7 @@ public final MethodResult receive(Optional<Double> timeout) throws LuaException
      * Send a websocket message to the connected server.
      *
      * @param message The message to send.
-     * @param binary  Whether this message should be treated as a
+     * @param binary  Whether this message should be treated as a binary message.
      * @throws LuaException If the message is too large.
      * @throws LuaException If the websocket has been closed.
      * @cc.changed 1.81.0 Added argument for binary mode.