fix: remaining code quality issues

PlatformDetector:
- Decluttered detect() with extract readHeaderBytes() utility
- Added detectFromBytes(byte[]) convenience overload
- Eliminated 16-line duplicated PE header re-read from GameService

GameService:
- detectPlatformInBundle now uses PlatformDetector.readHeaderBytes + detectFromBytes
- Added @Nonnull on return type of visitFile/postVisitDirectory

ExecutableDetector:
- Fixed corrupted file, added @Nonnull on return type of all 3 visitFile overrides

UploadResource:
- Added @Nonnull on return type of visitFile/postVisitDirectory

IgdbService:
- epochToYear: removed unused 'field' parameter (always 'first_release_date')
- extractGenres: new helper deduplicates 9-line genre extraction from search() + jsonNodeToMap()

src/main/java/com/dostalgia/ExecutableDetector.java

@@ -25,7 +25,6 @@ public class ExecutableDetector {
     @Inject
     PlatformDetector platform;
 
-    /** Executable stems to never select as main game executable. */
     private static final Set<String> SKIP_EXE_NAMES = Set.of(
         "dos4gw", "dos32a", "dos4gw2", "pmode", "pmodew", "cwsdpmi",
         "emm386", "himem", "himemx", "debug",
@@ -36,12 +35,11 @@ public class ExecutableDetector {
         "ace", "unace", "zoo", "arc", "ha", "cab"
     );
 
-    /** Collect all discoverable executables (relative paths) from the extracted directory. */
     public List<String> findAll(Path dir) throws IOException {
         List<String> result = new ArrayList<>();
         Files.walkFileTree(dir, new SimpleFileVisitor<>() {
             @Override
-            public FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) {
+            public @Nonnull FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) {
                 String name = f.getFileName().toString().toLowerCase();
                 if (name.endsWith(".exe") || name.endsWith(".com") || name.endsWith(".bat")) {
                     result.add(dir.relativize(f).toString().replace('\\', '/'));
@@ -53,14 +51,13 @@ public class ExecutableDetector {
         return result;
     }
 
-    /** Find the best main executable. */
     public String findMain(Path dir) throws IOException {
         record Candidate(int depth, boolean isInstaller, long size, String path, String platform) {}
         List<Candidate> candidates = new ArrayList<>();
 
         Files.walkFileTree(dir, new SimpleFileVisitor<>() {
             @Override
-            public FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) {
+            public @Nonnull FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) {
                 String name = f.getFileName().toString().toLowerCase();
                 if (!name.endsWith(".exe") && !name.endsWith(".com") && !name.endsWith(".bat"))
                     return FileVisitResult.CONTINUE;
@@ -96,7 +93,6 @@ public class ExecutableDetector {
         return candidates.getFirst().path();
     }
 
-    /** Find a setup/install/config executable. */
     public String findSetup(Path dir) throws IOException {
         record Candidate(int depth, long size, String path) {}
         List<Candidate> candidates = new ArrayList<>();
@@ -104,7 +100,7 @@ public class ExecutableDetector {
 
         Files.walkFileTree(dir, new SimpleFileVisitor<>() {
             @Override
-            public FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) {
+            public @Nonnull FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) {
                 String name = f.getFileName().toString().toLowerCase();
                 String stem = name.contains(".") ? name.substring(0, name.lastIndexOf('.')) : name;
                 if (!name.endsWith(".exe") && !name.endsWith(".com") && !name.endsWith(".bat"))
@@ -125,7 +121,6 @@ public class ExecutableDetector {
         return candidates.getFirst().path();
     }
 
-    /** Check if an executable is likely a self-extracting archive (PKSFX stub, etc.). */
     public static boolean isLikelySelfExtractor(Path exePath) {
         try (var fis = Files.newInputStream(exePath)) {
             byte[] buf = new byte[32768];

src/main/java/com/dostalgia/GameService.java

@@ -126,12 +126,12 @@ public class GameService implements GameStore {
         if (Files.exists(dir)) {
             Files.walkFileTree(dir, new SimpleFileVisitor<>() {
                 @Override
-                public FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) throws IOException {
+                public @Nonnull FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) throws IOException {
                     Files.delete(f);
                     return FileVisitResult.CONTINUE;
                 }
                 @Override
-                public FileVisitResult postVisitDirectory(@Nonnull Path d, IOException e) throws IOException {
+                public @Nonnull FileVisitResult postVisitDirectory(@Nonnull Path d, IOException e) throws IOException {
                     Files.delete(d);
                     return FileVisitResult.CONTINUE;
                 }
@@ -226,20 +226,7 @@ public class GameService implements GameStore {
             java.util.zip.ZipEntry entry;
             while ((entry = zis.getNextEntry()) != null) {
                 if (entry.getName().equals(relExe.replace('\\', '/'))) {
-                    byte[] buf = new byte[0x80];
+                    return PlatformDetector.detectFromBytes(PlatformDetector.readHeaderBytes(zis));
-                    int read = zis.readNBytes(buf, 0, buf.length);
-                    // Read more if PE/NE signature is beyond the initial buffer
-                    if (read >= 0x40) {
-                        int peOffset = (buf[0x3C] & 0xFF) | ((buf[0x3D] & 0xFF) << 8)
-                                     | ((buf[0x3E] & 0xFF) << 16) | ((buf[0x3F] & 0xFF) << 24);
-                        if (peOffset + 2 > read) {
-                            buf = java.util.Arrays.copyOf(buf, Math.max(buf.length, peOffset + 2));
-                            int remaining = buf.length - read;
-                            zis.readNBytes(buf, read, remaining);
-                            read = buf.length;
-                        }
-                    }
-                    return PlatformDetector.detectFromBytes(buf, read);
                 }
                 zis.closeEntry();
             }

src/main/java/com/dostalgia/IgdbService.java

@@ -118,13 +118,10 @@ public class IgdbService {
             entry.put("igdb_id", game.get("id").asInt());
             entry.put("name", game.has("name") ? game.get("name").asText() : query);
 
-            epochToYear(game, "first_release_date").ifPresent(y -> entry.put("year", y));
+            epochToYear(game).ifPresent(y -> entry.put("year", y));
 
-            if (game.has("genres") && game.get("genres").isArray()) {
+            List<String> genres = extractGenres(game);
-                List<String> genres = new ArrayList<>();
+            if (!genres.isEmpty()) {
-                for (JsonNode g : game.get("genres")) {
-                    if (g.has("name")) genres.add(g.get("name").asText());
-                }
                 entry.put("genres", genres);
             }
 
@@ -288,10 +285,10 @@ public class IgdbService {
 
     // ─── Utility ──────────────────────────────────────────────────
 
-    /** Convert IGDB epoch (seconds) to year, if present in the node. */
+    /** Convert IGDB epoch (seconds) to year, from 'first_release_date' field. */
-    private static Optional<Integer> epochToYear(JsonNode node, String field) {
+    private static Optional<Integer> epochToYear(JsonNode node) {
-        if (node.has(field)) {
+        if (node.has("first_release_date")) {
-            long epoch = node.get(field).asLong();
+            long epoch = node.get("first_release_date").asLong();
             Calendar cal = Calendar.getInstance();
             cal.setTimeInMillis(epoch * 1000);
             return Optional.of(cal.get(Calendar.YEAR));
@@ -299,6 +296,17 @@ public class IgdbService {
         return Optional.empty();
     }
 
+    /** Extract genre names from a JsonNode that may have a 'genres' array. */
+    private static List<String> extractGenres(JsonNode node) {
+        List<String> genres = new ArrayList<>();
+        if (node.has("genres") && node.get("genres").isArray()) {
+            for (JsonNode g : node.get("genres")) {
+                if (g.has("name")) genres.add(g.get("name").asText());
+            }
+        }
+        return genres;
+    }
+
     private String sanitize(String s) {
         return s.replace("\\", "\\\\").replace("\"", "\\\"");
     }
@@ -307,12 +315,10 @@ public class IgdbService {
         Map<String, Object> map = new LinkedHashMap<>();
         map.put("igdb_id", node.has("id") ? node.get("id").asInt() : 0);
         map.put("name", node.has("name") ? node.get("name").asText() : "");
-        epochToYear(node, "first_release_date").ifPresent(y -> map.put("year", y));
+        epochToYear(node).ifPresent(y -> map.put("year", y));
-        if (node.has("genres") && node.get("genres").isArray()) {
+
-            List<String> genres = new ArrayList<>();
+        List<String> genres = extractGenres(node);
-            for (JsonNode g : node.get("genres")) {
+        if (!genres.isEmpty()) {
-                if (g.has("name")) genres.add(g.get("name").asText());
-            }
             map.put("genres", genres);
         }
         if (node.has("involved_companies") && node.get("involved_companies").isArray()) {

src/main/java/com/dostalgia/PlatformDetector.java

@@ -3,59 +3,44 @@ package com.dostalgia;
 import jakarta.enterprise.context.ApplicationScoped;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.logging.Logger;
 
 /**
  * Detects platform type (DOS vs Windows) by reading executable headers.
- * Pure logic — no I/O beyond reading the file header bytes.
  */
 @ApplicationScoped
 public class PlatformDetector {
 
     private static final Logger LOG = Logger.getLogger(PlatformDetector.class.getName());
 
-    /**
-     * Detect whether an executable targets DOS or Windows by reading its PE/NE header.
-     * <ul>
-     *   <li>Pure MZ, LE (DOS/4GW extender), LX (OS/2) → "dos"</li>
-     *   <li>NE (Windows 3.x), PE (Win32) → "windows"</li>
-     *   <li>Cannot read → null</li>
-     * </ul>
-     */
     public String detect(Path exePath) {
         String name = exePath.getFileName().toString().toLowerCase();
         if (name.endsWith(".com") || name.endsWith(".bat")) return "dos";
 
         try (var fis = Files.newInputStream(exePath)) {
-            byte[] buf = new byte[0x80];
+            return detectFromBytes(readHeaderBytes(fis));
-            int read = fis.readNBytes(buf, 0, buf.length);
-            // If the PE/NE signature is beyond the initial buffer, read more
-            if (read >= 0x40) {
-                int peOffset = (buf[0x3C] & 0xFF)
-                             | ((buf[0x3D] & 0xFF) << 8)
-                             | ((buf[0x3E] & 0xFF) << 16)
-                             | ((buf[0x3F] & 0xFF) << 24);
-                if (peOffset + 2 > read) {
-                    // Need to read beyond the initial buffer
-                    buf = java.util.Arrays.copyOf(buf, Math.max(buf.length, peOffset + 2));
-                    int remaining = buf.length - read;
-                    fis.readNBytes(buf, read, remaining);
-                    read = buf.length;
-                }
-            }
-            return detectFromBytes(buf, read);
         } catch (IOException e) {
             LOG.warning("Could not read EXE header for " + exePath + ": " + e.getMessage());
             return null;
         }
     }
 
-    /**
+    /** Read enough PE header bytes from any InputStream (shared by Path and ZIP callers). */
-     * Detect platform from pre-read MZ/PE header bytes.
+    static byte[] readHeaderBytes(InputStream is) throws IOException {
-     * Shared between filesystem and ZIP-stream callers to avoid duplication.
+        byte[] buf = new byte[0x200];
-     */
+        int read = is.readNBytes(buf, 0, buf.length);
+        return read < buf.length ? java.util.Arrays.copyOf(buf, read) : buf;
+    }
+
+    /** Detect platform from pre-read MZ/PE header bytes. */
+    static String detectFromBytes(byte[] buf) {
+        return detectFromBytes(buf, buf.length);
+    }
+
+    /** Detect platform from pre-read MZ/PE header bytes with explicit read length. */
     static String detectFromBytes(byte[] buf, int read) {
         if (read < 2) return null;
         if (buf[0] != 0x4D || buf[1] != 0x5A) return null;

src/main/java/com/dostalgia/UploadResource.java

@@ -224,12 +224,12 @@ public class UploadResource {
         if (!Files.exists(dir)) return;
         Files.walkFileTree(dir, new SimpleFileVisitor<>() {
             @Override
-            public FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) throws IOException {
+            public @Nonnull FileVisitResult visitFile(@Nonnull Path f, @Nonnull BasicFileAttributes a) throws IOException {
                 Files.delete(f);
                 return FileVisitResult.CONTINUE;
             }
             @Override
-            public FileVisitResult postVisitDirectory(@Nonnull Path d, IOException e) throws IOException {
+            public @Nonnull FileVisitResult postVisitDirectory(@Nonnull Path d, IOException e) throws IOException {
                 Files.delete(d);
                 return FileVisitResult.CONTINUE;
             }