initial commit

internal/gamefile.go

@@ -0,0 +1,70 @@
+package oplcli
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+func scanGameFileForID(filename string) (string, error) {
+	file, err := os.Open(filename)
+	if err != nil {
+		return "", fmt.Errorf("failed to open file: %w", err)
+	}
+	defer file.Close()
+
+	const bufferSize = 1024 * 1024 // 1MB
+	buffer := make([]byte, bufferSize)
+
+	n, err := file.Read(buffer)
+	if err != nil && n == 0 {
+		return "", fmt.Errorf("failed to read file: %w", err)
+	}
+
+	pattern := regexp.MustCompile(`(SLUS|SLES|SLPS|SCUS|SCES|SCPS)[_-]?\d{3}[\._]\d{2}`)
+
+	match := pattern.Find(buffer[:n])
+	if match != nil {
+		gameID := string(match)
+		return normalizeGameID(gameID), nil
+	}
+
+	return "", fmt.Errorf("no PS2 game ID found in file")
+}
+
+func normalizeGameID(id string) string {
+	s := strings.ReplaceAll(id, "_", "-")
+	s = strings.ReplaceAll(s, ".", "")
+	s = strings.ToUpper(s)
+
+	return s
+}
+
+func renameGameFile(filePath, gameName string) (string, error) {
+	ext := filepath.Ext(filePath)
+	dir := filepath.Dir(filePath)
+
+	newPath := filepath.Join(dir, gameName+ext)
+
+	if filePath == newPath {
+		return filePath, nil
+	}
+
+	// Do not overwrite existing files
+	if _, err := os.Stat(newPath); err == nil {
+		return "", fmt.Errorf("file already exists: %s", newPath)
+	} else if !os.IsNotExist(err) {
+		return "", fmt.Errorf("failed to check destination: %w", err)
+	}
+
+	// rename file
+	err := os.Rename(filePath, newPath)
+	if err != nil {
+		return "", fmt.Errorf("failed to rename file: %w", err)
+	}
+
+	return newPath, nil
+}
+