Improved exceptions thrown in the data framework. ZippedAlphaChunkStore can now detect subdirectories that the world is in.

src/com/sk89q/worldedit/data/AlphaChunkStore.java

@@ -49,11 +49,16 @@ public class AlphaChunkStore extends NestedFileChunkStore {
      * @param f2
      * @param name
      * @return
+     * @throws DataException
      * @throws IOException
      */
     protected InputStream getInputStream(String f1, String f2, String name)
-            throws IOException {
+            throws DataException, IOException {
         String file = f1 + File.separator + f2 + File.separator + name;
+        try {
             return new FileInputStream(new File(path, file));
+        } catch (FileNotFoundException e) {
+            throw new MissingChunkException();
+        }
     }
 }

src/com/sk89q/worldedit/data/Chunk.java

@@ -57,12 +57,14 @@ public class Chunk {
         rootZ = ((IntTag)getChildTag(
                 rootTag.getValue(), "zPos", IntTag.class)).getValue();
 
-        if (blocks.length != 16384) {
+        if (blocks.length != 32768) {
-            throw new InvalidFormatException("Chunk blocks byte array expected to contain 16,384 blocks");
+            throw new InvalidFormatException("Chunk blocks byte array expected "
+                    + "to be 32,768 bytes; found " + blocks.length);
         }
 
         if (data.length != 16384) {
-            throw new InvalidFormatException("Chunk block data byte array expected to contain 16,384 blocks");
+            throw new InvalidFormatException("Chunk block data byte array "
+                    + "expected to be 16,384 bytes; found " + data.length);
         }
     }
 
@@ -74,8 +76,10 @@ public class Chunk {
      * @throws DataException
      */
     public int getBlockID(Vector pos) throws DataException {
-        int index = pos.getBlockY() * 16 * 16
+        int x = pos.getBlockX() - rootX * 16;
-                + (pos.getBlockZ() - rootZ) * 16 + (pos.getBlockX() - rootX);
+        int y = pos.getBlockY();
+        int z = pos.getBlockZ() - rootZ * 16;
+        int index = y + (z * 128 + (x * 128 * 16));
 
         try {
             return blocks[index];
@@ -92,11 +96,19 @@ public class Chunk {
      * @throws DataException
      */
     public int getBlockData(Vector pos) throws DataException {
-        int index = pos.getBlockY() * 16 * 16
+        int x = pos.getBlockX() - rootX * 16;
-                + (pos.getBlockZ() - rootZ) * 16 + (pos.getBlockX() - rootX);
+        int y = pos.getBlockY();
+        int z = pos.getBlockZ() - rootZ * 16;
+        int index = y + (z * 128 + (x * 128 * 16));
+        boolean shift = index % 2 == 0;
+        index /= 2;
 
         try {
-            return data[index];
+            if (!shift) {
+                return (data[index] & 0xF0) >> 4;
+            } else {
+                return data[index] & 0xF;
+            }
         } catch (IndexOutOfBoundsException e) {
             throw new DataException("Chunk does not contain position " + pos);
         }

src/com/sk89q/worldedit/data/ChunkStore.java

@@ -49,11 +49,11 @@ public abstract class ChunkStore {
      *
      * @param pos
      * @return tag
-     * @throws ChunkStoreException
+     * @throws DataException
      * @throws IOException
      */
     public abstract CompoundTag getChunkTag(Vector2D pos)
-            throws ChunkStoreException, IOException;
+            throws DataException, IOException;
 
     /**
      * Get a chunk at a location.

src/com/sk89q/worldedit/data/ChunkStoreException.java

@@ -27,4 +27,8 @@ public class ChunkStoreException extends DataException {
     public ChunkStoreException(String msg) {
         super(msg);
     }
+
+    public ChunkStoreException() {
+        super();
+    }
 }

src/com/sk89q/worldedit/data/DataException.java

@@ -28,4 +28,8 @@ public class DataException extends Exception {
     public DataException(String msg) {
         super(msg);
     }
+    
+    public DataException() {
+        super();
+    }
 }

src/com/sk89q/worldedit/data/MissingChunkException.java

@@ -0,0 +1,48 @@
+// $Id$
+/*
+ * WorldEdit
+ * Copyright (C) 2010 sk89q <http://www.sk89q.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package com.sk89q.worldedit.data;
+
+import com.sk89q.worldedit.Vector2D;
+
+/**
+ *
+ * @author sk89q
+ */
+public class MissingChunkException extends ChunkStoreException {
+    private Vector2D pos;
+
+    public MissingChunkException() {
+        super();
+    }
+
+    public MissingChunkException(Vector2D pos) {
+        super();
+        this.pos = pos;
+    }
+
+    /**
+     * Get chunk position in question. May be null if unknown.
+     * 
+     * @return
+     */
+    public Vector2D getChunkPosition() {
+        return pos;
+    }
+}

src/com/sk89q/worldedit/data/NestedFileChunkStore.java

@@ -21,6 +21,7 @@ package com.sk89q.worldedit.data;
 
 import com.sk89q.worldedit.Vector2D;
 import java.io.*;
+import java.util.*;
 import org.jnbt.*;
 
 /**
@@ -36,9 +37,11 @@ public abstract class NestedFileChunkStore extends ChunkStore {
      *
      * @param pos
      * @return tag
+     * @throws DataException
+     * @throws IOException
      */
     public CompoundTag getChunkTag(Vector2D pos)
-            throws ChunkStoreException, IOException {
+            throws DataException, IOException {
         int x = pos.getBlockX();
         int z = pos.getBlockZ();
         
@@ -51,15 +54,37 @@ public abstract class NestedFileChunkStore extends ChunkStore {
         NBTInputStream nbt = new NBTInputStream(stream);
         Tag tag;
 
+        try {
             tag = nbt.readTag();
             if (!(tag instanceof CompoundTag)) {
                 throw new ChunkStoreException("CompoundTag expected for chunk; got "
-                    + tag.getClass());
+                        + tag.getClass().getName());
             }
 
-        stream.close();
+            Map<String,Tag> children = (Map<String,Tag>)((CompoundTag)tag).getValue();
+            CompoundTag rootTag = null;
 
-        return (CompoundTag)tag;
+            // Find Level tag
+            for (Map.Entry<String,Tag> entry : children.entrySet()) {
+                if (entry.getKey().equals("Level")) {
+                    if (entry.getValue() instanceof CompoundTag) {
+                        rootTag = (CompoundTag)entry.getValue();
+                        break;
+                    } else {
+                        throw new ChunkStoreException("CompoundTag expected for 'Level'; got "
+                                + entry.getValue().getClass().getName());
+                    }
+                }
+            }
+
+            if (rootTag == null) {
+                throw new ChunkStoreException("Missing root 'Level' tag");
+            }
+
+            return rootTag;
+        } finally {
+            stream.close();
+        }
     }
 
     /**
@@ -83,5 +108,5 @@ public abstract class NestedFileChunkStore extends ChunkStore {
      * @throws IOException
      */
     protected abstract InputStream getInputStream(String f1, String f2, String name)
-            throws IOException;
+            throws IOException, DataException;
 }

src/com/sk89q/worldedit/data/ZippedAlphaChunkStore.java

@@ -21,6 +21,7 @@ package com.sk89q.worldedit.data;
 
 import java.io.*;
 import java.util.zip.*;
+import java.util.Enumeration;
 
 /**
  * Represents the chunk store used by Minecraft alpha but zipped.
@@ -43,7 +44,8 @@ public class ZippedAlphaChunkStore extends NestedFileChunkStore {
 
     /**
      * Create an instance. The folder argument lets you choose a folder or
-     * path to look into in the ZIP for the files.
+     * path to look into in the ZIP for the files. Use a blank string for
+     * the folder to not look into a subdirectory.
      *
      * @param zipFile
      * @param folder
@@ -59,7 +61,8 @@ public class ZippedAlphaChunkStore extends NestedFileChunkStore {
     }
 
     /**
-     * Create an instance.
+     * Create an instance. The subfolder containing the chunk data will
+     * be detected.
      *
      * @param zipFile
      * @param folder
@@ -81,13 +84,46 @@ public class ZippedAlphaChunkStore extends NestedFileChunkStore {
      * @param name
      * @return
      * @throws IOException
+     * @throws DataException
      */
     protected InputStream getInputStream(String f1, String f2, String name)
-            throws IOException {
+            throws IOException, DataException {
         String file = f1 + "/" + f2 + "/" + name;
+
+        // Detect subfolder for the world's files
+        if (folder != null) {
+            if (!folder.equals("")) {
+                file = folder + "/" + file;
+            }
+        } else {
+            ZipEntry testEntry = zip.getEntry("level.dat");
+
+            // So, the data is not in the root directory
+            if (testEntry == null) {
+                // Let's try a world/ sub-directory
+                testEntry = zip.getEntry("world/level.dat");
+
+                // So not there either...
+                if (testEntry == null) {
+                    for (Enumeration e = zip.entries(); e.hasMoreElements(); ) {
+                        testEntry = (ZipEntry)e.nextElement();
+
+                        // Whoo, found level.dat!
+                        if (testEntry.getName().matches(".+/level\\.dat")) {
+                            file = testEntry.getName().replaceAll("level\\.dat$", "")
+                                    + file;
+                            break;
+                        }
+                    }
+                } else {
+                    file = "world/" + file;
+                }
+            }
+        }
+
         ZipEntry entry = zip.getEntry(file);
         if (entry == null) {
-            throw new IOException("ZIP doesn't contain chunk");
+            throw new MissingChunkException();
         }
         try {
             return zip.getInputStream(entry);