fix: allow webinterface schematic format to be detected (#2901)

* fix: allow webinterface schematic format to be detected

* chore: address review

worldedit-core/src/main/java/com/fastasyncworldedit/core/util/MainUtil.java

@@ -701,7 +701,7 @@ public class MainUtil {
 
     public static File resolve(File dir, String filename, @Nullable ClipboardFormat format, boolean allowDir) {
         if (format != null) {
-            if (!filename.matches(".*\\.[\\w].*")) {
+            if (!filename.matches(".*\\.\\w.*")) {
                 filename = filename + "." + format.getPrimaryFileExtension();
             }
             return MainUtil.resolveRelative(new File(dir, filename));
@@ -712,7 +712,7 @@ public class MainUtil {
                 return file;
             }
         }
-        if (filename.matches(".*\\.[\\w].*")) {
+        if (filename.matches(".*\\.\\w.*")) {
             File file = MainUtil.resolveRelative(new File(dir, filename));
             if (file.exists()) {
                 return file;

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

@@ -69,18 +69,18 @@ import org.enginehub.piston.exception.StopExecutionException;
 
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
+import java.io.Closeable;
+import java.io.EOFException;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.net.URI;
-import java.net.URISyntaxException;
-import java.net.URL;
-import java.nio.channels.Channels;
-import java.nio.channels.ReadableByteChannel;
 import java.io.OutputStream;
+import java.net.URI;
+import java.net.URL;
 import java.nio.file.Files;
+import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -91,8 +91,8 @@ import java.util.Map;
 import java.util.Objects;
 import java.util.UUID;
 import java.util.concurrent.Callable;
-import java.util.function.Consumer;
 import java.util.concurrent.ThreadLocalRandom;
+import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.regex.Pattern;
 
@@ -326,13 +326,13 @@ public class SchematicCommands {
 
         //FAWE start
         ClipboardFormat format;
-        InputStream in = null;
+        InputStream in;
         // if format is set explicitly, do not look up by extension!
         boolean noExplicitFormat = formatName == null;
         if (noExplicitFormat) {
             formatName = "fast";
         }
-        try {
+        try(final Closer closer = Closer.create()) {
             URI uri;
             if (formatName.startsWith("url:")) {
                 String t = filename;
@@ -346,11 +346,31 @@ public class SchematicCommands {
                 }
                 UUID uuid = UUID.fromString(filename.substring(4));
                 URL webUrl = new URL(Settings.settings().WEB.URL);
-                format = ClipboardFormats.findByAlias(formatName);
+                if ((format = ClipboardFormats.findByAlias(formatName)) == null) {
+                    actor.print(Caption.of("worldedit.schematic.unknown-format", TextComponent.of(formatName)));
+                    return;
+                }
+                // The interface requires the correct schematic extension - otherwise it can't be downloaded
+                // So it basically only supports .schem files (sponge v2 + v3) - or the correct extensions is specified manually
+                // Sadly it's not really an API endpoint but spits out the HTML source of the uploader - so no real handling
+                // can happen
                 URL url = new URL(webUrl, "uploads/" + uuid + "." + format.getPrimaryFileExtension());
-                ReadableByteChannel byteChannel = Channels.newChannel(url.openStream());
-                in = Channels.newInputStream(byteChannel);
-                uri = url.toURI();
+                final Path temp = Files.createTempFile("faweremoteschem", null);
+                final File tempFile = temp.toFile();
+                // delete temporary file when we're done
+                closer.register((Closeable) () -> Files.deleteIfExists(temp));
+                // write schematic into temporary file
+                try (final InputStream urlIn = new BufferedInputStream(url.openStream());
+                    final OutputStream tempOut = new BufferedOutputStream(new FileOutputStream(tempFile))) {
+                    urlIn.transferTo(tempOut);
+                }
+                // No format is specified -> try or fail
+                if (noExplicitFormat && (format = ClipboardFormats.findByFile(tempFile)) == null) {
+                    actor.print(Caption.of("fawe.worldedit.schematic.schematic.load-failure", TextComponent.of(filename)));
+                    return;
+                }
+                in = new FileInputStream(tempFile);
+                uri = temp.toUri();
             } else {
                 File saveDir = worldEdit.getWorkingDirectoryPath(config.saveDir).toFile();
                 File dir = Settings.settings().PATHS.PER_PLAYER_SCHEMATICS ? new File(saveDir, actor.getUniqueId().toString()) : saveDir;
@@ -378,7 +398,7 @@ public class SchematicCommands {
                     }
                     if (!noExplicitFormat) {
                         format = ClipboardFormats.findByAlias(formatName);
-                    } else if (filename.matches(".*\\.[\\w].*")) {
+                    } else if (filename.matches(".*\\.\\w.*")) {
                         format = ClipboardFormats
                                 .findByExplicitExtension(filename.substring(filename.lastIndexOf('.') + 1));
                     } else {
@@ -412,6 +432,7 @@ public class SchematicCommands {
                 in = new FileInputStream(file);
                 uri = file.toURI();
             }
+            closer.register(in);
             format.hold(actor, uri, in);
             if (randomRotate) {
                 AffineTransform transform = new AffineTransform();
@@ -422,19 +443,18 @@ public class SchematicCommands {
             actor.print(Caption.of("fawe.worldedit.schematic.schematic.loaded", filename));
         } catch (IllegalArgumentException e) {
             actor.print(Caption.of("worldedit.schematic.unknown-filename", TextComponent.of(filename)));
-        } catch (URISyntaxException | IOException e) {
+        } catch (EOFException e) {
+            // EOFException is extending IOException - but the IOException error is too generic.
+            // EOF mostly occurs when there was unexpected content in the schematic - due to the wrong reader (= version)
+            actor.print(Caption.of("fawe.worldedit.schematic.schematic.load-failure",
+                    TextComponent.of(e.getMessage() != null ? e.getMessage() : "EOFException"))); // often null...
+            LOGGER.error("Error loading a schematic", e);
+        } catch (IOException e) {
             actor.print(Caption.of("worldedit.schematic.file-not-exist", TextComponent.of(Objects.toString(e.getMessage()))));
             LOGGER.warn("Failed to load a saved clipboard", e);
         } catch (Exception e) {
             actor.print(Caption.of("fawe.worldedit.schematic.schematic.load-failure", TextComponent.of(e.getMessage())));
             LOGGER.error("Error loading a schematic", e);
-        } finally {
-            if (in != null) {
-                try {
-                    in.close();
-                } catch (IOException ignored) {
-                }
-            }
         }
         //FAWE end
     }