fix

pkg/logger/logger.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"path/filepath"
 	"runtime"
 	"strings"
 	"sync"
@@ -37,7 +38,11 @@ var (
 )
 
 type Logger struct {
-	file *os.File
+	file         *os.File
+	filePath     string
+	maxSizeBytes int64
+	maxAgeDays   int
+	fileMu       sync.Mutex
 }
 
 type LogEntry struct {
@@ -68,9 +73,25 @@ func GetLevel() LogLevel {
 }
 
 func EnableFileLogging(filePath string) error {
+	return EnableFileLoggingWithRotation(filePath, 20, 3)
+}
+
+func EnableFileLoggingWithRotation(filePath string, maxSizeMB, maxAgeDays int) error {
 	mu.Lock()
 	defer mu.Unlock()
 
+	if maxSizeMB <= 0 {
+		maxSizeMB = 20
+	}
+	if maxAgeDays <= 0 {
+		maxAgeDays = 3
+	}
+
+	dir := filepath.Dir(filePath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("failed to create log directory: %w", err)
+	}
+
 	file, err := os.OpenFile(filePath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
 	if err != nil {
 		return fmt.Errorf("failed to open log file: %w", err)
@@ -81,6 +102,12 @@ func EnableFileLogging(filePath string) error {
 	}
 
 	logger.file = file
+	logger.filePath = filePath
+	logger.maxSizeBytes = int64(maxSizeMB) * 1024 * 1024
+	logger.maxAgeDays = maxAgeDays
+	if err := logger.cleanupOldLogFiles(); err != nil {
+		log.Println("Failed to clean up old log files:", err)
+	}
 	log.Println("File logging enabled:", filePath)
 	return nil
 }
@@ -92,6 +119,9 @@ func DisableFileLogging() {
 	if logger.file != nil {
 		logger.file.Close()
 		logger.file = nil
+		logger.filePath = ""
+		logger.maxSizeBytes = 0
+		logger.maxAgeDays = 0
 		log.Println("File logging disabled")
 	}
 }
@@ -119,7 +149,9 @@ func logMessage(level LogLevel, component string, message string, fields map[str
 	if logger.file != nil {
 		jsonData, err := json.Marshal(entry)
 		if err == nil {
-			logger.file.WriteString(string(jsonData) + "\n")
+			if err := logger.writeLine(append(jsonData, '\n')); err != nil {
+				log.Println("Failed to write file log:", err)
+			}
 		}
 	}
 
@@ -143,6 +175,88 @@ func logMessage(level LogLevel, component string, message string, fields map[str
 	}
 }
 
+func (l *Logger) writeLine(line []byte) error {
+	l.fileMu.Lock()
+	defer l.fileMu.Unlock()
+
+	if l.file == nil {
+		return nil
+	}
+
+	if l.maxSizeBytes > 0 {
+		if err := l.rotateIfNeeded(int64(len(line))); err != nil {
+			return err
+		}
+	}
+
+	_, err := l.file.Write(line)
+	return err
+}
+
+func (l *Logger) rotateIfNeeded(nextWrite int64) error {
+	info, err := l.file.Stat()
+	if err != nil {
+		return err
+	}
+
+	if info.Size()+nextWrite <= l.maxSizeBytes {
+		return nil
+	}
+
+	if err := l.file.Close(); err != nil {
+		return err
+	}
+
+	backupPath := fmt.Sprintf("%s.%s", l.filePath, time.Now().UTC().Format("20060102-150405"))
+	if err := os.Rename(l.filePath, backupPath); err != nil {
+		return err
+	}
+
+	file, err := os.OpenFile(l.filePath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0644)
+	if err != nil {
+		return err
+	}
+	l.file = file
+
+	return l.cleanupOldLogFiles()
+}
+
+func (l *Logger) cleanupOldLogFiles() error {
+	if l.maxAgeDays <= 0 || l.filePath == "" {
+		return nil
+	}
+
+	dir := filepath.Dir(l.filePath)
+	base := filepath.Base(l.filePath)
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return err
+	}
+
+	cutoff := time.Now().AddDate(0, 0, -l.maxAgeDays)
+	for _, entry := range entries {
+		if entry.IsDir() {
+			continue
+		}
+
+		name := entry.Name()
+		// Only delete rotated files like clawgo.log.20260213-120000
+		if !strings.HasPrefix(name, base+".") {
+			continue
+		}
+
+		info, err := entry.Info()
+		if err != nil {
+			continue
+		}
+		if info.ModTime().Before(cutoff) {
+			_ = os.Remove(filepath.Join(dir, name))
+		}
+	}
+
+	return nil
+}
+
 func formatComponent(component string) string {
 	if component == "" {
 		return ""