(Feat): Initial Commit

internal/archiver/detect.go

@@ -0,0 +1,107 @@
+package archiver
+
+import (
+	"bytes"
+	"compress/gzip"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"zipprine/internal/models"
+)
+
+func DetectArchiveType(path string) (models.ArchiveType, error) {
+	// First, try by extension
+	ext := strings.ToLower(filepath.Ext(path))
+	switch ext {
+	case ".zip":
+		return models.ZIP, nil
+	case ".gz":
+		if strings.HasSuffix(strings.ToLower(path), ".tar.gz") {
+			return models.TARGZ, nil
+		}
+		return models.GZIP, nil
+	case ".tar":
+		return models.TAR, nil
+	case ".tgz":
+		return models.TARGZ, nil
+	}
+
+	// Try by magic bytes
+	file, err := os.Open(path)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+
+	header := make([]byte, 512)
+	n, err := file.Read(header)
+	if err != nil && err != io.EOF {
+		return "", err
+	}
+	header = header[:n]
+
+	// ZIP magic: PK (0x504B)
+	if len(header) >= 2 && header[0] == 0x50 && header[1] == 0x4B {
+		return models.ZIP, nil
+	}
+
+	// GZIP magic: 0x1F 0x8B
+	if len(header) >= 2 && header[0] == 0x1F && header[1] == 0x8B {
+		// Check if it's a tar.gz by trying to decompress and check for tar header
+		file.Seek(0, 0)
+		gzReader, err := gzip.NewReader(file)
+		if err == nil {
+			defer gzReader.Close()
+			tarHeader := make([]byte, 512)
+			if n, _ := gzReader.Read(tarHeader); n >= 257 {
+				// TAR magic: "ustar" at offset 257
+				if bytes.Equal(tarHeader[257:262], []byte("ustar")) {
+					return models.TARGZ, nil
+				}
+			}
+		}
+		return models.GZIP, nil
+	}
+
+	// TAR magic: "ustar" at offset 257
+	if len(header) >= 262 && bytes.Equal(header[257:262], []byte("ustar")) {
+		return models.TAR, nil
+	}
+
+	return models.AUTO, nil
+}
+
+func Analyze(path string) (*models.ArchiveInfo, error) {
+	archiveType, err := DetectArchiveType(path)
+	if err != nil {
+		return nil, err
+	}
+
+	switch archiveType {
+	case models.ZIP:
+		return analyzeZip(path)
+	case models.TARGZ:
+		return analyzeTar(path, true)
+	case models.TAR:
+		return analyzeTar(path, false)
+	case models.GZIP:
+		// For GZIP, provide basic file info
+		file, err := os.Open(path)
+		if err != nil {
+			return nil, err
+		}
+		defer file.Close()
+
+		fileStat, _ := file.Stat()
+		return &models.ArchiveInfo{
+			Type:           models.GZIP,
+			CompressedSize: fileStat.Size(),
+			FileCount:      1,
+			Files:          []models.FileInfo{},
+		}, nil
+	default:
+		return nil, nil
+	}
+}