feat: restructure code; add size and ext checks (#39)

- Refractor code
- Add file size and extension checkers
- Change repair workflow to use zurg

pkg/repair/misc.go

@@ -0,0 +1,131 @@
+package repair
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"time"
+)
+
+func parseSchedule(schedule string) (time.Duration, error) {
+	if schedule == "" {
+		return time.Hour, nil // default 60m
+	}
+
+	// Check if it's a time-of-day format (HH:MM)
+	if strings.Contains(schedule, ":") {
+		return parseTimeOfDay(schedule)
+	}
+
+	// Otherwise treat as duration interval
+	return parseDurationInterval(schedule)
+}
+
+func parseTimeOfDay(schedule string) (time.Duration, error) {
+	now := time.Now()
+	scheduledTime, err := time.Parse("15:04", schedule)
+	if err != nil {
+		return 0, fmt.Errorf("invalid time format: %s. Use HH:MM in 24-hour format", schedule)
+	}
+
+	// Convert scheduled time to today
+	scheduleToday := time.Date(
+		now.Year(), now.Month(), now.Day(),
+		scheduledTime.Hour(), scheduledTime.Minute(), 0, 0,
+		now.Location(),
+	)
+
+	if scheduleToday.Before(now) {
+		scheduleToday = scheduleToday.Add(24 * time.Hour)
+	}
+
+	return scheduleToday.Sub(now), nil
+}
+
+func parseDurationInterval(interval string) (time.Duration, error) {
+	if len(interval) < 2 {
+		return 0, fmt.Errorf("invalid interval format: %s", interval)
+	}
+
+	numStr := interval[:len(interval)-1]
+	unit := interval[len(interval)-1]
+
+	num, err := strconv.Atoi(numStr)
+	if err != nil {
+		return 0, fmt.Errorf("invalid number in interval: %s", numStr)
+	}
+
+	switch unit {
+	case 'm':
+		return time.Duration(num) * time.Minute, nil
+	case 'h':
+		return time.Duration(num) * time.Hour, nil
+	case 'd':
+		return time.Duration(num) * 24 * time.Hour, nil
+	case 's':
+		return time.Duration(num) * time.Second, nil
+	default:
+		return 0, fmt.Errorf("invalid unit in interval: %c", unit)
+	}
+}
+
+func fileIsSymlinked(file string) bool {
+	info, err := os.Lstat(file)
+	if err != nil {
+		return false
+	}
+	return info.Mode()&os.ModeSymlink != 0
+}
+
+func getSymlinkTarget(file string) string {
+	if fileIsSymlinked(file) {
+		target, err := os.Readlink(file)
+		if err != nil {
+			return ""
+		}
+		if !filepath.IsAbs(target) {
+			dir := filepath.Dir(file)
+			target = filepath.Join(dir, target)
+		}
+		return target
+	}
+	return ""
+}
+
+func fileIsReadable(filePath string) error {
+	// First check if file exists and is accessible
+	info, err := os.Stat(filePath)
+	if err != nil {
+		return err
+	}
+
+	// Check if it's a regular file
+	if !info.Mode().IsRegular() {
+		return fmt.Errorf("not a regular file")
+	}
+
+	// Try to read the first 1024 bytes
+	err = checkFileStart(filePath)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func checkFileStart(filePath string) error {
+	f, err := os.Open(filePath)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	// Read first 1kb
+	buffer := make([]byte, 1024)
+	_, err = f.Read(buffer)
+	if err != nil {
+		return err
+	}
+	return nil
+}