Add copyright header support for board files (Fixes #7936)

megamek/src/megamek/client/ui/clientGUI/GUIPreferences.java

@@ -423,6 +423,7 @@ public class GUIPreferences extends PreferenceStoreProxy {
     public static final String BOARD_EDIT_LOAD_SIZE_HEIGHT = "BoardEditLoadSizeHeight";
     public static final String BOARD_EDIT_LOAD_SIZE_WIDTH = "BoardEditLoadSizeWidth";
     public static final String BOARD_EDIT_RANDOM_DIALOG_START = "BoardEditRandomDialogStart";
+    public static final String BOARD_SAVE_INCLUDE_LICENSE = "BoardSaveIncludeLicense";
     public static final String ALLY_UNIT_COLOR = "AllyUnitColor";
     public static final String MY_UNIT_COLOR = "MyUnitColor";
     public static final String ENEMY_UNIT_COLOR = "EnemyUnitColor";
@@ -519,6 +520,7 @@ protected GUIPreferences() {
               .getPreferenceStore("GUIPreferences", getClass().getName(), "megamek.client.ui.swing.GUIPreferences");
 
         store.setDefault(BOARD_EDIT_RANDOM_DIALOG_START, false);
+        store.setDefault(BOARD_SAVE_INCLUDE_LICENSE, true);
         setDefault(ADVANCED_NO_SAVE_NAG, false);
         store.setDefault(ADVANCED_SAVE_LOBBY_ON_START, false);
         store.setDefault(ADVANCED_MOVE_STEP_DELAY, 50);
@@ -1778,6 +1780,10 @@ public boolean getBoardEdRndStart() {
         return store.getBoolean(BOARD_EDIT_RANDOM_DIALOG_START);
     }
 
+    public boolean getBoardSaveIncludeLicense() {
+        return store.getBoolean(BOARD_SAVE_INCLUDE_LICENSE);
+    }
+
     public void setShadowMap(boolean state) {
         store.setValue(SHADOW_MAP, state);
     }
@@ -2712,6 +2718,10 @@ public void setBoardEdRndStart(boolean b) {
         store.setValue(BOARD_EDIT_RANDOM_DIALOG_START, b);
     }
 
+    public void setBoardSaveIncludeLicense(boolean includeLicense) {
+        store.setValue(BOARD_SAVE_INCLUDE_LICENSE, includeLicense);
+    }
+
     // region Colours
     public Color getMyUnitColor() {
         return getColor(MY_UNIT_COLOR);

megamek/src/megamek/common/board/Board.java

@@ -43,6 +43,8 @@
 import java.io.*;
 import java.nio.charset.StandardCharsets;
 import java.util.*;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 import megamek.client.ui.clientGUI.GUIPreferences;
 import megamek.common.Configuration;
@@ -108,6 +110,36 @@ public class Board implements Serializable {
     private static final int UNDEFINED_MIN_ELEV = 10000;
     private static final int UNDEFINED_MAX_ELEV = -10000;
 
+    /**
+     * License header for board files, compatible with Creative Commons BY-NC-SA 4.0. The year is dynamically set to the
+     * current year when saving.
+     */
+    public static final String LICENSE_HEADER = """
+          # MegaMek Data (C) %s by The MegaMek Team is licensed under CC BY-NC-SA 4.0.
+          # To view a copy of this license, visit https://creativecommons.org/licenses/by-nc-sa/4.0/
+          #
+          # NOTICE: The MegaMek organization is a non-profit group of volunteers
+          # creating free software for the BattleTech community.
+          #
+          # MechWarrior, BattleMech, `Mech and AeroTech are registered trademarks
+          # of The Topps Company, Inc. All Rights Reserved.
+          #
+          # Catalyst Game Labs and the Catalyst Game Labs logo are trademarks of
+          # InMediaRes Productions, LLC.
+          #
+          # MechWarrior Copyright Microsoft Corporation. MegaMek Data was created under
+          # Microsoft's "Game Content Usage Rules"
+          # <https://www.xbox.com/en-US/developers/rules> and it is not endorsed by or
+          # affiliated with Microsoft.
+          """;
+
+    /** Regex pattern to extract the copyright year(s) from board file headers. */
+    private static final Pattern COPYRIGHT_YEAR_PATTERN = Pattern.compile(
+          "#\\s*MegaMek Data \\(C\\)\\s*(\\d{4})(?:-(\\d{4}))?");
+
+    /** The original copyright year from the loaded board file, or -1 if none found. */
+    private int originalCopyrightYear = -1;
+
     // The min and max elevation values for this board.
     // set when getMinElevation/getMax is called for the first time.
     private int minElevation = UNDEFINED_MIN_ELEV;
@@ -1002,7 +1034,28 @@ public void load(InputStream is, @Nullable List<String> errors, boolean continue
         Hex[] nd = new Hex[0];
         int index = 0;
         resetStoredElevation();
-        try (InputStreamReader isr = new InputStreamReader(is);
+        originalCopyrightYear = -1;
+
+        // Read the entire content first to extract copyright year from header
+        String content;
+        try {
+            content = new String(is.readAllBytes(), StandardCharsets.UTF_8);
+        } catch (IOException e) {
+            logger.error(e, "Error reading board file content");
+            return;
+        }
+
+        // Extract original copyright year from header if present
+        Matcher matcher = COPYRIGHT_YEAR_PATTERN.matcher(content);
+        if (matcher.find()) {
+            try {
+                originalCopyrightYear = Integer.parseInt(matcher.group(1));
+            } catch (NumberFormatException ignored) {
+                // Keep default -1
+            }
+        }
+
+        try (InputStreamReader isr = new InputStreamReader(new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8)));
               BufferedReader br = new BufferedReader(isr)) {
             StreamTokenizer st = new StreamTokenizer(br);
             st.eolIsSignificant(true);
@@ -1179,10 +1232,35 @@ private boolean isValid(Hex[] data, int width, int height, @Nullable List<String
     }
 
     /**
-     * Writes data for the board, as text to the OutputStream
+     * Writes data for the board, as text to the OutputStream.
+     * Uses the GUI preference to determine whether to include the license header.
+     *
+     * @param os the OutputStream to write to
      */
     public void save(OutputStream os) {
+        boolean includeLicense = GUIPreferences.getInstance().getBoardSaveIncludeLicense();
+        save(os, includeLicense);
+    }
+
+    /**
+     * Writes data for the board, as text to the OutputStream.
+     *
+     * @param os             the OutputStream to write to
+     * @param includeLicense if true, writes the CC BY-NC-SA 4.0 license header at the start of the file
+     */
+    public void save(OutputStream os, boolean includeLicense) {
         try (Writer w = new OutputStreamWriter(os)) {
+            if (includeLicense) {
+                int currentYear = Calendar.getInstance().get(Calendar.YEAR);
+                String yearString;
+                if ((originalCopyrightYear > 0) && (originalCopyrightYear < currentYear)) {
+                    yearString = originalCopyrightYear + "-" + currentYear;
+                } else {
+                    yearString = String.valueOf(currentYear);
+                }
+                w.write(LICENSE_HEADER.formatted(yearString));
+                w.write("\r\n");
+            }
             w.write("size " + width + ' ' + height + "\r\n");
             if (!roadsAutoExit) {
                 w.write("option exit_roads_to_pavement false\r\n");

megamek/src/megamek/utilities/BoardsTagger.java

@@ -53,6 +53,7 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
+import java.util.function.Consumer;
 import java.util.stream.Collectors;
 
 import megamek.common.Configuration;
@@ -380,28 +381,35 @@ public static void runBoardTagger() {
     }
 
     /**
-     * Recursively scans the supplied file/directory for any boards and auto-tags them.
+     * Recursively scans the supplied file/directory and applies the given processor to each file found.
+     *
+     * @param file          the file or directory to scan
+     * @param fileProcessor the action to perform on each file
      */
-    private static void scanForBoards(File file, Map<String, List<String>> boardCheckSum) {
+    private static void scanBoardFiles(File file, Consumer<File> fileProcessor) {
         if (file.isDirectory()) {
             String[] fileList = file.list();
             if (fileList != null) {
                 for (String filename : fileList) {
                     File filepath = new File(file, filename);
-                    if (filepath.isDirectory()) {
-                        scanForBoards(new File(file, filename), boardCheckSum);
-                    } else {
-                        tagBoard(filepath);
-                        checkSum(boardCheckSum, filepath);
-                    }
+                    scanBoardFiles(filepath, fileProcessor);
                 }
             }
         } else {
-            tagBoard(file);
-            checkSum(boardCheckSum, file);
+            fileProcessor.accept(file);
         }
     }
 
+    /**
+     * Recursively scans the supplied file/directory for any boards and auto-tags them.
+     */
+    private static void scanForBoards(File file, Map<String, List<String>> boardCheckSum) {
+        scanBoardFiles(file, boardFile -> {
+            tagBoard(boardFile);
+            checkSum(boardCheckSum, boardFile);
+        });
+    }
+
     /**
      * Scans the board for the types and number of terrains present, deletes old automatic tags and applies new
      * automatic tags as appropriate.
@@ -494,4 +502,65 @@ private static void checkSum(Map<String, List<String>> boardCheckSum, File board
             logger.error(e, "SHA-256 Algorithm Can't be Found");
         }
     }
+
+    /**
+     * Runs the copyright header updater on all boards in the default boards directory. Adds or updates the MegaMek Data
+     * copyright header to all valid board files.
+     */
+    public static void runCopyrightHeaderUpdater() {
+        try {
+            File boardDir = Configuration.boardsDir();
+            scanForBoardsAndUpdateHeaders(boardDir);
+        } catch (Exception ex) {
+            logger.error(ex, "Copyright header updater cannot scan boards");
+        }
+
+        logger.info("Copyright header update finished.");
+    }
+
+    /**
+     * Recursively scans the supplied file/directory for any boards and updates their copyright headers.
+     *
+     * @param file the file or directory to scan
+     */
+    private static void scanForBoardsAndUpdateHeaders(File file) {
+        scanBoardFiles(file, BoardsTagger::updateCopyrightHeader);
+    }
+
+    /**
+     * Updates the copyright header on a single board file. If the board already has a copyright header (lines starting
+     * with #), it is replaced. If not, a new header is added at the beginning of the file.
+     *
+     * @param boardFile the board file to update
+     */
+    private static void updateCopyrightHeader(File boardFile) {
+        // If this isn't a board, ignore it
+        if (!boardFile.toString().endsWith(".board")) {
+            return;
+        }
+
+        // Load the board
+        Board board = new Board();
+        try (InputStream is = new FileInputStream(boardFile)) {
+            List<String> errors = new ArrayList<>();
+            board.load(is, errors, true);
+            if (!errors.isEmpty()) {
+                logger.debug("Board has errors, skipping: {}", boardFile);
+                return;
+            }
+        } catch (Exception e) {
+            logger.error(e, "Could not load board: {}", boardFile);
+            return;
+        }
+
+        // Re-save the board with the license header
+        try (OutputStream os = new FileOutputStream(boardFile)) {
+            board.save(os, true);
+            if (DEBUG) {
+                logger.debug("Updated copyright header: {}", boardFile);
+            }
+        } catch (Exception ex) {
+            logger.error(ex, "Could not save board: {}", boardFile);
+        }
+    }
 }