WIP first pass at structure reading

worldedit-core/src/main/java/com/sk89q/worldedit/command/SchematicCommands.java

@@ -21,6 +21,7 @@
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
+import com.google.common.io.Files;
 import com.sk89q.minecraft.util.commands.Command;
 import com.sk89q.minecraft.util.commands.CommandContext;
 import com.sk89q.minecraft.util.commands.CommandException;
@@ -245,7 +246,8 @@ public void formats(Actor actor) throws WorldEditException {
             help = "List all schematics in the schematics directory\n" +
                     " -d sorts by date, oldest first\n" +
                     " -n sorts by date, newest first\n" +
-                    " -p <page> prints the requested page\n"
+                    " -p <page> prints the requested page\n" +
+                    "Note: Format is not thoroughly verified until loading."
     )
     @CommandPermissions("worldedit.schematic.list")
     public void list(Actor actor, CommandContext args, @Switch('p') @Optional("1") int page) throws WorldEditException {
@@ -328,10 +330,12 @@ private List<String> listFiles(String prefix, File[] files) {
             StringBuilder build = new StringBuilder();
 
             build.append("\u00a72");
-            ClipboardFormat format = ClipboardFormats.findByFile(file);
+            //ClipboardFormat format = ClipboardFormats.findByFile(file);
+            ClipboardFormat format = ClipboardFormats.getFileExtensionMap().get(Files.getFileExtension(file.getName()))
+                    .stream().findFirst().orElse(null);
             boolean inRoot = file.getParentFile().getName().equals(prefix);
             build.append(inRoot ? file.getName() : file.getPath().split(Pattern.quote(prefix + File.separator))[1])
-                    .append(": ").append(format == null ? "Unknown" : format.getName());
+                    .append(": ").append(format == null ? "Unknown" : format.getName() + "*");
             result.add(build.toString());
         }
         return result;

worldedit-core/src/main/java/com/sk89q/worldedit/extent/clipboard/io/BuiltInClipboardFormat.java

@@ -119,6 +119,39 @@ public boolean isFormat(File file) {
                 return false;
             }
 
+            return true;
+        }
+    },
+    MINECRAFT_STRUCTURE("structure") {
+        @Override
+        public String getPrimaryFileExtension() {
+            return "nbt";
+        }
+
+        @Override
+        public ClipboardReader getReader(InputStream inputStream) throws IOException {
+            NBTInputStream nbtStream = new NBTInputStream(new GZIPInputStream(inputStream));
+            return new MinecraftStructureReader(nbtStream);
+        }
+
+        @Override
+        public ClipboardWriter getWriter(OutputStream outputStream) throws IOException {
+            throw new IOException("This format does not support saving");
+        }
+
+        @Override
+        public boolean isFormat(File file) {
+            try (NBTInputStream str = new NBTInputStream(new GZIPInputStream(new FileInputStream(file)))) {
+                NamedTag rootTag = str.readNamedTag();
+                CompoundTag structureTag = (CompoundTag) rootTag.getTag();
+                Map<String, Tag> structure = structureTag.getValue();
+                if (!structure.containsKey("DataVersion")) {
+                    return false;
+                }
+            } catch (Exception e) {
+                return false;
+            }
+
             return true;
         }
     };

worldedit-core/src/main/java/com/sk89q/worldedit/extent/clipboard/io/MinecraftStructureReader.java

@@ -0,0 +1,156 @@
+package com.sk89q.worldedit.extent.clipboard.io;
+
+import com.google.common.collect.Maps;
+import com.sk89q.jnbt.CompoundTag;
+import com.sk89q.jnbt.IntTag;
+import com.sk89q.jnbt.ListTag;
+import com.sk89q.jnbt.NBTInputStream;
+import com.sk89q.jnbt.NamedTag;
+import com.sk89q.jnbt.StringTag;
+import com.sk89q.jnbt.Tag;
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.entity.BaseEntity;
+import com.sk89q.worldedit.extension.input.InputParseException;
+import com.sk89q.worldedit.extension.input.ParserContext;
+import com.sk89q.worldedit.extent.clipboard.BlockArrayClipboard;
+import com.sk89q.worldedit.extent.clipboard.Clipboard;
+import com.sk89q.worldedit.math.BlockVector3;
+import com.sk89q.worldedit.math.Vector3;
+import com.sk89q.worldedit.regions.CuboidRegion;
+import com.sk89q.worldedit.util.Location;
+import com.sk89q.worldedit.world.block.BaseBlock;
+import com.sk89q.worldedit.world.block.BlockState;
+import com.sk89q.worldedit.world.entity.EntityType;
+import com.sk89q.worldedit.world.entity.EntityTypes;
+import com.sk89q.worldedit.world.storage.NBTConversions;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.logging.Logger;
+import java.util.stream.Collectors;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Reads Mincraft structure files.
+ * {@link https://minecraft.gamepedia.com/Structure_block_file_format}
+ */
+public class MinecraftStructureReader extends NBTSchematicReader {
+    private static final Logger log = Logger.getLogger(MinecraftStructureReader.class.getCanonicalName());
+    private final NBTInputStream inputStream;
+
+    /**
+     * Create a new instance.
+     *
+     * @param inputStream the input stream to read from
+     */
+    public MinecraftStructureReader(NBTInputStream inputStream) {
+        checkNotNull(inputStream);
+        this.inputStream = inputStream;
+    }
+
+    @Override
+    public Clipboard read() throws IOException {
+        NamedTag rootTag = inputStream.readNamedTag();
+        // MC structures are all unnamed, but this doesn't seem to be necessary
+        CompoundTag structureTag = (CompoundTag) rootTag.getTag();
+        Map<String, Tag> structure = structureTag.getValue();
+        int version = requireTag(structure, "DataVersion", IntTag.class).getValue();
+        List<Tag> size = requireTag(structure, "size", ListTag.class).getValue();
+        if (size.size() != 3) {
+            throw new IOException("Invalid size list tag in structure.");
+        }
+        int width = ((IntTag) size.get(0)).getValue();
+        int height = ((IntTag) size.get(1)).getValue();
+        int length = ((IntTag) size.get(2)).getValue();
+
+        // TODO support random (or non-random) palette from 'palettes' tag
+        List<CompoundTag> paletteObject = requireTag(structure, "palette", ListTag.class).getValue()
+                .stream().map(t -> ((CompoundTag) t)).collect(Collectors.toList());
+        Map<Integer, BlockState> palette = new HashMap<>();
+        ParserContext parserContext = new ParserContext();
+        parserContext.setRestricted(false);
+        parserContext.setTryLegacy(false);
+        parserContext.setPreferringWildcard(false);
+
+        for (int i = 0; i < paletteObject.size(); i++) {
+            CompoundTag palettePart = paletteObject.get(i);
+            String blockName = palettePart.getString("Name");
+            if (blockName.isEmpty()) throw new IOException("Palette block name empty.");
+            StringBuilder stateBuilder = new StringBuilder(blockName);
+            Tag props = palettePart.getValue().getOrDefault("Properties", null);
+            if (props instanceof CompoundTag) {
+                CompoundTag properties = ((CompoundTag) props);
+                if (!properties.getValue().isEmpty())
+                {
+                    stateBuilder.append('[');
+                    stateBuilder.append(properties.getValue().entrySet().stream().map(e ->
+                            e.getKey() + "=" + (String) e.getValue().getValue()).collect(Collectors.joining(",")));
+                    stateBuilder.append(']');
+                }
+            }
+            BlockState state;
+            try {
+                state = WorldEdit.getInstance().getBlockFactory().parseFromInput(stateBuilder.toString(), parserContext).toImmutableState();
+            } catch (InputParseException e) {
+                throw new IOException("Invalid BlockState in structure: " + palettePart +
+                        ". Are you missing a mod or using a structure made in a newer version of Minecraft?");
+            }
+            palette.put(i, state);
+        }
+
+        BlockArrayClipboard clipboard = new BlockArrayClipboard(
+                new CuboidRegion(BlockVector3.ZERO, BlockVector3.at(width, height, length).subtract(BlockVector3.ONE)));
+
+        for (Tag blockTag : requireTag(structure, "blocks", ListTag.class).getValue()) {
+            CompoundTag block = (CompoundTag) blockTag;
+            ListTag pos = requireTag(block.getValue(), "pos", ListTag.class);
+            BlockVector3 vec = BlockVector3.at(pos.getInt(0), pos.getInt(1), pos.getInt(2));
+            int state = requireTag(block.getValue(), "state", IntTag.class).getValue();
+            BlockState blockState = palette.get(state);
+            CompoundTag nbt = getTag(block, CompoundTag.class, "nbt");
+            try {
+                if (nbt == null) {
+                    clipboard.setBlock(vec, blockState);
+                } else {
+                    Map<String, Tag> values = Maps.newHashMap(nbt.getValue());
+                    values.put("x", new IntTag(vec.getBlockX()));
+                    values.put("y", new IntTag(vec.getBlockY()));
+                    values.put("z", new IntTag(vec.getBlockZ()));
+                    BaseBlock baseBlock = blockState.toBaseBlock(nbt);
+                }
+            } catch (WorldEditException e) {
+                throw new IOException("Failed to load a block in the schematic");
+            }
+        }
+
+        List<Tag> entityTags = requireTag(structure, "entities", ListTag.class).getValue();
+        for (Tag tag : entityTags) {
+            CompoundTag compound = (CompoundTag) tag;
+            CompoundTag nbt = requireTag(compound.getValue(), "nbt", CompoundTag.class);
+            Location location = NBTConversions.toLocation(clipboard, compound.getListTag("pos"),
+                    nbt.getListTag("Rotation"));
+            String id = requireTag(nbt.getValue(), "id", StringTag.class).getValue();
+
+            if (!id.isEmpty()) {
+                EntityType entityType = EntityTypes.get(id.toLowerCase());
+                if (entityType != null) {
+                    BaseEntity state = new BaseEntity(entityType, compound);
+                    clipboard.createEntity(location, state);
+                } else {
+                    log.warning("Unknown entity when pasting schematic: " + id.toLowerCase());
+                }
+            }
+        }
+
+        return clipboard;
+    }
+
+    @Override
+    public void close() throws IOException {
+        inputStream.close();
+    }
+}

worldedit-core/src/main/java/com/sk89q/worldedit/extent/clipboard/io/SpongeSchematicReader.java

@@ -143,7 +143,7 @@ private Clipboard readVersion1(Map<String, Tag> schematic) throws IOException {
             try {
                 state = WorldEdit.getInstance().getBlockFactory().parseFromInput(palettePart, parserContext).toImmutableState();
             } catch (InputParseException e) {
-                throw new IOException("Invalid BlockState in schematic: " + palettePart + ". Are you missing a mod of using a schematic made in a newer version of Minecraft?");
+                throw new IOException("Invalid BlockState in schematic: " + palettePart + ". Are you missing a mod or using a schematic made in a newer version of Minecraft?");
             }
             palette.put(id, state);
         }