Initial project scaffolding

- main.go: CLI entry point with flag parsing
- gitignore.go: .gitignore loading and parsing
- sync.go: initial sync with manifest tracking
- watcher.go: fsnotify-based file watcher with debouncing
- Dockerfile: multi-stage build for Alpine runtime

1 files changed, 106 insertions, 0 deletions

diff --git a/sync.go b/sync.go
new file mode 100644
index 0000000..293f20b
--- /dev/null
+++ b/sync.go
@@ -0,0 +1,106 @@
+package main
+
+import (
+	"io"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	ignore "github.com/sabhiram/go-gitignore"
+)
+
+type FileMeta struct {
+	Size     int64
+	Mode     os.FileMode
+	Symlink  string
+}
+
+type Manifest struct {
+	Files map[string]FileMeta
+}
+
+func initialSync(hostDir, dataDir string, rules *ignore.GitIgnore, dryRun bool) (*Manifest, error) {
+	manifest := &Manifest{Files: make(map[string]FileMeta)}
+
+	err := filepath.Walk(hostDir, func(path string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+
+		relPath, err := filepath.Rel(hostDir, path)
+		if err != nil {
+			return err
+		}
+
+		if relPath == "." {
+			return nil
+		}
+
+		if relPath == ".git" || strings.HasPrefix(relPath, ".git"+string(filepath.Separator)) {
+			return filepath.SkipDir
+		}
+
+		if rules.MatchesPath(relPath) {
+			if info.IsDir() {
+				return filepath.SkipDir
+			}
+			return nil
+		}
+
+		destPath := filepath.Join(dataDir, relPath)
+
+		linkTarget := ""
+		if info.Mode()&os.ModeSymlink != 0 {
+			linkTarget, err = os.Readlink(path)
+			if err != nil {
+				return err
+			}
+		}
+
+		meta := FileMeta{
+			Size:    info.Size(),
+			Mode:    info.Mode(),
+			Symlink: linkTarget,
+		}
+		manifest.Files[relPath] = meta
+
+		if dryRun {
+			log.Printf("[dry-run] would sync: %s", relPath)
+			return nil
+		}
+
+		if info.IsDir() {
+			return os.MkdirAll(destPath, info.Mode())
+		}
+
+		if err := os.MkdirAll(filepath.Dir(destPath), 0755); err != nil {
+			return err
+		}
+
+		if linkTarget != "" {
+			return os.Symlink(linkTarget, destPath)
+		}
+
+		return copyFile(path, destPath, info.Mode())
+	})
+
+	return manifest, err
+}
+
+func copyFile(src, dst string, mode os.FileMode) error {
+	srcFile, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer srcFile.Close()
+
+	dstFile, err := os.OpenFile(dst, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, mode)
+	if err != nil {
+		return err
+	}
+	defer dstFile.Close()
+
+	_, err = io.Copy(dstFile, srcFile)
+	return err
+}