launcher/bootstrap/src/main/java/me/sashegdev/zernmc/launcher/Bootstrap.java

@@ -54,6 +54,7 @@ public class Bootstrap {
         logDir = baseDir.resolve("logs");
         Files.createDirectories(logDir);
         javafxPath = baseDir.resolve("lib").resolve("javafx");
+        rotateLogs();
         
         log("=== ZernMC Launcher ===");
         
@@ -371,11 +372,50 @@ public class Bootstrap {
         return javaBin;
     }
     
+    private static void rotateLogs() {
+        // Minecraft-style: archive previous latest.log as .log.gz, keep unlimited.
+        try {
+            Path latest = logDir.resolve("latest.log");
+            if (Files.exists(latest) && Files.size(latest) > 0) {
+                String ts = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd_HH-mm-ss"));
+                int n = 1;
+                Path archive;
+                do {
+                    archive = logDir.resolve(ts + (n == 1 ? "" : "-" + n) + ".log.gz");
+                    n++;
+                } while (Files.exists(archive));
+                gzip(archive, latest);
+                Files.deleteIfExists(latest);
+            }
+        } catch (Exception e) {
+            System.out.println("[Bootstrap] rotate error: " + e.getMessage());
+        }
+        // Migrate old unlimited log.
+        try {
+            Files.deleteIfExists(logDir.resolve("launcher.log"));
+        } catch (Exception ignored) {
+        }
+    }
+
+    private static void gzip(Path archive, Path source) {
+        try (java.io.InputStream in = Files.newInputStream(source);
+             java.io.OutputStream out = Files.newOutputStream(archive);
+             java.util.zip.GZIPOutputStream gz = new java.util.zip.GZIPOutputStream(out)) {
+            byte[] buf = new byte[65536];
+            int n;
+            while ((n = in.read(buf)) > 0) {
+                gz.write(buf, 0, n);
+            }
+        } catch (Exception e) {
+            System.out.println("[Bootstrap] gzip error: " + e.getMessage());
+        }
+    }
+
     private static void log(String msg) {
         String entry = "[" + LocalDateTime.now().format(DateTimeFormatter.ofPattern("HH:mm:ss")) + "] " + msg;
         System.out.println(entry);
         try {
-            Files.writeString(logDir.resolve("launcher.log"), entry + "\n", 
+            Files.writeString(logDir.resolve("latest.log"), entry + "\n", 
                 StandardOpenOption.CREATE, StandardOpenOption.APPEND);
         } catch (Exception ignored) {}
         if (ui != null) ui.setStatus(msg);
@@ -881,7 +921,7 @@ public class Bootstrap {
         // Exit
         info.put("exit_code", exitCode);
         info.put("stderr", stderr != null ? stderr : "");
-        info.put("launcher_log", readFileSafe(logDir.resolve("launcher.log"), 200));
+        info.put("launcher_log", readFileSafe(logDir.resolve("latest.log"), 200));
 
         // System
         Map<String, Object> system = new HashMap<>();

launcher/launcher/src/main/java/sashegdev/zernmc/launcher/Bootstrap.java

@@ -211,7 +211,7 @@ public class Bootstrap {
         String entry = "[" + LocalDateTime.now().format(DateTimeFormatter.ofPattern("HH:mm:ss")) + "] " + msg;
         System.out.println(entry);
         try {
-            Files.writeString(logDir.resolve("launcher.log"), entry + "\n",
+            Files.writeString(logDir.resolve("latest.log"), entry + "\n",
                 StandardOpenOption.CREATE, StandardOpenOption.APPEND);
         } catch (Exception ignored) {}
     }

launcher/launcher/src/main/java/sashegdev/zernmc/launcher/utils/LauncherLogger.java

@@ -53,11 +53,10 @@ public class LauncherLogger {
         try {
             Path logsDir = Paths.get("").toAbsolutePath().resolve("logs");
             Files.createDirectories(logsDir);
-            logFile = logsDir.resolve("launcher.log");
+            rotateLogs(logsDir);
+            logFile = logsDir.resolve("latest.log");
 
-            Files.writeString(logFile,
-                "=== Launcher Log " + LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")) + " ===\n",
-                StandardOpenOption.CREATE, StandardOpenOption.APPEND);
+            Files.writeString(logFile, sessionHeader(), StandardOpenOption.CREATE);
 
             System.out.println("[LauncherLogger] initialized, log: " + logFile.toAbsolutePath());
         } catch (Exception e) {
@@ -66,6 +65,62 @@ public class LauncherLogger {
         }
     }
 
+    private static String sessionHeader() {
+        String ts = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss"));
+        String os = System.getProperty("os.name") + " " + System.getProperty("os.version")
+                + " " + System.getProperty("os.arch");
+        String java = System.getProperty("java.version") + " (" + System.getProperty("java.vendor") + ")";
+        String mem = (Runtime.getRuntime().maxMemory() / (1024 * 1024)) + " MB";
+        return "== ZernMC Launcher =======================================================\n"
+                + "== Started: " + ts + "\n"
+                + "== OS: " + os + "\n"
+                + "== Java: " + java + "\n"
+                + "== Max memory: " + mem + "\n"
+                + "====================================================================\n";
+    }
+
+    /**
+     * Minecraft-style rotation: compress the previous latest.log into a dated
+     * .log.gz archive (unlimited history), then remove the legacy launcher.log.
+     */
+    private static void rotateLogs(Path logsDir) {
+        // Legacy one-instance log from older builds: delete it, it is replaced by latest.log.
+        try {
+            Files.deleteIfExists(logsDir.resolve("launcher.log"));
+        } catch (Exception ignored) {
+        }
+
+        Path latest = logsDir.resolve("latest.log");
+        try {
+            if (Files.exists(latest) && Files.size(latest) > 0) {
+                String ts = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd_HH-mm-ss"));
+                int n = 1;
+                Path archive;
+                do {
+                    archive = logsDir.resolve(ts + (n == 1 ? "" : "-" + n) + ".log.gz");
+                    n++;
+                } while (Files.exists(archive));
+                gzip(logsDir, archive, latest);
+                Files.deleteIfExists(latest);
+            }
+        } catch (Exception e) {
+            System.err.println("[LauncherLogger] rotate error: " + e.getMessage());
+        }
+    }
+
+    private static void gzip(Path logsDir, Path archive, Path source) {
+        try (var in = Files.newInputStream(source);
+             var gz = new java.util.zip.GZIPOutputStream(Files.newOutputStream(archive))) {
+            byte[] buf = new byte[65536];
+            int n;
+            while ((n = in.read(buf)) > 0) {
+                gz.write(buf, 0, n);
+            }
+        } catch (Exception e) {
+            System.err.println("[LauncherLogger] gzip error: " + e.getMessage());
+        }
+    }
+
     public static Path getLogFile() {
         return logFile;
     }

launcher/pom.xml

@@ -20,7 +20,7 @@
 
     <properties>
         <revision>1.0.16</revision>
-        <hotfix>13</hotfix>
+        <hotfix>14</hotfix>
         <maven.compiler.source>21</maven.compiler.source>
         <maven.compiler.target>21</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>