Scaffold Java 21 multi-module project with UMD ISO + SFO parsing

- Gradle Kotlin DSL multi-module (core, ui, cli) with JPMS modules
- UMD ISO 9660 reader (UmdIsoReader/UmdIsoFile + sector devices)
- SFO (param.sfo) parser
- 'dump' CLI command: metadata + recursive file listing
- JUnit 5 + AssertJ tests (SFO and ISO reader)
- Switch license from MIT to GPL-3.0-or-later

cli/build.gradle.kts

@@ -0,0 +1,18 @@
+plugins {
+    application
+}
+
+java {
+    toolchain {
+        languageVersion = JavaLanguageVersion.of(21)
+    }
+}
+
+application {
+    mainModule = "dev.quoije.umd.cli"
+    mainClass = "dev.quoije.umd.cli.Main"
+}
+
+dependencies {
+    implementation(project(":core"))
+}

cli/src/main/java/dev/quoije/umd/cli/Main.java

@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+package dev.quoije.umd.cli;
+
+import dev.quoije.umd.iso.UmdIsoFile;
+import dev.quoije.umd.iso.UmdIsoReader;
+import dev.quoije.umd.sfo.Sfo;
+
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
+import java.util.Map;
+
+/** Command-line front-end for the UMD player library. */
+public final class Main {
+
+    private static final String USAGE = "usage: umdplayer dump <image.iso>";
+
+    private Main() {
+    }
+
+    public static void main(String[] args) {
+        if (args.length == 0) {
+            System.err.println(USAGE);
+            System.exit(2);
+        }
+
+        int exitCode;
+        try {
+            exitCode = switch (args[0]) {
+                case "dump" -> dump(requireArg(args, 1));
+                case "help", "--help", "-h" -> {
+                    System.out.println(USAGE);
+                    yield 0;
+                }
+                default -> {
+                    System.err.println("unknown command: " + args[0]);
+                    System.err.println(USAGE);
+                    yield 2;
+                }
+            };
+        } catch (Exception e) {
+            System.err.println("error: " + e.getMessage());
+            exitCode = 1;
+        }
+        System.exit(exitCode);
+    }
+
+    private static String requireArg(String[] args, int index) {
+        if (args.length <= index) {
+            System.err.println(USAGE);
+            System.exit(2);
+        }
+        return args[index];
+    }
+
+    private static int dump(String imagePath) throws IOException {
+        Path path = Path.of(imagePath);
+        try (UmdIsoReader iso = new UmdIsoReader(path)) {
+            System.out.println("Image:     " + path.toAbsolutePath());
+            System.out.println("Sectors:   " + iso.getNumSectors()
+                    + " (" + (iso.getNumSectors() * 2048L) + " bytes)");
+            System.out.println("Joliet:    " + iso.hasJolietExtension());
+            System.out.println();
+
+            printSfo(iso);
+            System.out.println();
+            printTree(iso);
+        }
+        return 0;
+    }
+
+    private static void printSfo(UmdIsoReader iso) throws IOException {
+        byte[] sfoBytes = readFile(iso, "UMD_VIDEO/param.sfo");
+        if (sfoBytes == null) {
+            System.out.println("param.sfo: not found");
+            return;
+        }
+
+        Sfo sfo = Sfo.parse(sfoBytes);
+        System.out.println("param.sfo entries:");
+        for (Map.Entry<String, Sfo.Entry> entry : sfo.entries().entrySet()) {
+            String value = switch (entry.getValue().format()) {
+                case Sfo.FORMAT_INT32 -> Integer.toString(entry.getValue().asInt());
+                case Sfo.FORMAT_UTF8 -> entry.getValue().asString();
+                default -> "(" + entry.getValue().data().length + " bytes)";
+            };
+            System.out.printf("  %-20s = %s%n", entry.getKey(), value);
+        }
+
+        String discId = sfo.getString("DISC_ID");
+        if (discId == null || discId.isBlank()) {
+            byte[] umdData = readFile(iso, "UMD_DATA.BIN");
+            if (umdData != null && umdData.length >= 9) {
+                discId = new String(umdData, 0, 9, StandardCharsets.US_ASCII);
+                System.out.println("  (DISC_ID from UMD_DATA.BIN: " + discId + ")");
+            }
+        }
+    }
+
+    private static void printTree(UmdIsoReader iso) throws IOException {
+        System.out.println("Files:");
+        printDirectory(iso, "", 0);
+    }
+
+    private static void printDirectory(UmdIsoReader iso, String path, int depth) throws IOException {
+        String[] files = iso.listDirectory(path);
+        for (String file : files) {
+            if (file.equals(".") || file.equals("\01")) {
+                continue;
+            }
+            String child = path.isEmpty() ? file : path + "/" + file;
+            if (iso.isDirectory(child)) {
+                System.out.println("  ".repeat(depth) + "D " + file);
+                printDirectory(iso, child, depth + 1);
+            } else {
+                try (UmdIsoFile umdFile = iso.getFile(child)) {
+                    System.out.printf("%s%10d  %s%n", "  ".repeat(depth), umdFile.length(), file);
+                }
+            }
+        }
+    }
+
+    private static byte[] readFile(UmdIsoReader iso, String path) throws IOException {
+        if (!iso.hasFile(path)) {
+            return null;
+        }
+        try (UmdIsoFile file = iso.getFile(path)) {
+            byte[] buffer = new byte[(int) file.length()];
+            file.readFully(buffer);
+            return buffer;
+        }
+    }
+}

cli/src/main/java/module-info.java

@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+module dev.quoije.umd.cli {
+    requires dev.quoije.umd.core;
+}