chore: start on reader (class exists at least)

worldedit-core/src/main/java/com/fastasyncworldedit/core/extent/clipboard/io/FastSchematicReaderV3.java

@@ -0,0 +1,45 @@
+package com.fastasyncworldedit.core.extent.clipboard.io;
+
+import com.sk89q.jnbt.NBTConstants;
+import com.sk89q.jnbt.NBTInputStream;
+import com.sk89q.worldedit.WorldEdit;
+import com.sk89q.worldedit.extension.platform.Capability;
+import com.sk89q.worldedit.extent.clipboard.Clipboard;
+import com.sk89q.worldedit.extent.clipboard.io.ClipboardReader;
+import com.sk89q.worldedit.world.DataFixer;
+
+import java.io.DataInputStream;
+import java.io.IOException;
+import java.util.Objects;
+
+@SuppressWarnings("removal") // JNBT
+public class FastSchematicReaderV3 implements ClipboardReader {
+
+    private final DataInputStream dataStream;
+    private final NBTInputStream nbtStream;
+
+    public FastSchematicReaderV3(DataInputStream dataInputStream, NBTInputStream inputStream) {
+        this.dataStream = Objects.requireNonNull(dataInputStream, "dataInputStream");
+        this.nbtStream = Objects.requireNonNull(inputStream, "inputStream");
+    }
+
+    @Override
+    public Clipboard read() throws IOException {
+        final DataFixer dataFixer =
+                WorldEdit.getInstance().getPlatformManager().queryCapability(Capability.WORLD_EDITING).getDataFixer();
+        dataStream.skipNBytes(1 + 2); // 1 Byte = TAG_Compound, 2 Bytes = Short (Length of tag name = "")
+        dataStream.skipNBytes(1 + 2 + 9); // as above + 9 bytes = "Schematic"
+
+        byte type;
+        while ((type = dataStream.readByte()) != NBTConstants.TYPE_END) {
+            
+        }
+        return null;
+    }
+
+    @Override
+    public void close() throws IOException {
+        nbtStream.close(); // closes the DataInputStream implicitly
+    }
+
+}

worldedit-core/src/main/java/com/fastasyncworldedit/core/extent/clipboard/io/FastSchematicWriterV3.java

@@ -5,7 +5,6 @@ import com.fastasyncworldedit.core.util.IOUtil;
 import com.sk89q.jnbt.CompoundTag;
 import com.sk89q.jnbt.NBTConstants;
 import com.sk89q.jnbt.NBTOutputStream;
-import com.sk89q.jnbt.Tag;
 import com.sk89q.worldedit.WorldEdit;
 import com.sk89q.worldedit.entity.BaseEntity;
 import com.sk89q.worldedit.entity.Entity;
@@ -30,14 +29,13 @@ import java.io.IOException;
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
-import java.util.Map;
 import java.util.Objects;
 import java.util.function.Function;
 
 @SuppressWarnings("removal") // Yes, JNBT is deprecated - we know
 public class FastSchematicWriterV3 implements ClipboardWriter {
 
-    private static final int CURRENT_VERSION = 3;
+    public static final int CURRENT_VERSION = 3;
 
     private static final int MAX_SIZE = Short.MAX_VALUE - Short.MIN_VALUE;
     private final NBTOutputStream outputStream;

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

@@ -61,7 +61,7 @@ public enum BuiltInClipboardFormat implements ClipboardFormat {
     FAST_NEW("new_fast") { // For testing purposes
         @Override
         public ClipboardReader getReader(final InputStream inputStream) throws IOException {
-            return SPONGE_V3_SCHEMATIC.getReader(inputStream);
+            return SPONGE_V3_SCHEMATIC.getReader(inputStream); // TODO: use FastSchematicReaderV3 when finished
         }
 
         @Override
@@ -80,6 +80,36 @@ public enum BuiltInClipboardFormat implements ClipboardFormat {
         @Override
         public boolean isFormat(final File file) {
             return FAST.isFormat(file);
+            /**
+             * TODO: test if this actually works
+             * try (final DataInputStream stream = new DataInputStream(new GZIPInputStream(Files.newInputStream(file.toPath())));
+             *                  final NBTInputStream nbt = new NBTInputStream(stream)) {
+             *                 if (stream.readByte() != NBTConstants.TYPE_COMPOUND) {
+             *                     return false;
+             *                 }
+             *                 stream.readShort(); // TAG name length ("" = 0), no need to read name as no bytes are written for root tag
+             *                 if (stream.readByte() != NBTConstants.TYPE_COMPOUND) {
+             *                     return false;
+             *                 }
+             *                 stream.readShort(); // TAG name length ("Schematic" = 9)
+             *                 stream.skipNBytes(9); // "Schematic"
+             *
+             *                 // We can't guarantee the specific order of nbt data, so scan and skip, if required
+             *                 do {
+             *                     byte type = stream.readByte();
+             *                     String name = stream.readUTF();
+             *                     if (type == NBTConstants.TYPE_END) {
+             *                         return false;
+             *                     }
+             *                     if (type == NBTConstants.TYPE_INT && name.equals("Version")) {
+             *                         return stream.readInt() == FastSchematicWriterV3.CURRENT_VERSION;
+             *                     }
+             *                     nbt.readTagPayloadLazy(type, 1);
+             *                 } while (true);
+             *             } catch (IOException ignored) {
+             *             }
+             *             return false;
+             */
         }
 
         @Override