1 files changed, 63 insertions, 0 deletions
diff --git a/internal/github/filesystem.go b/internal/github/filesystem.go
new file mode 100644
index 0000000..3f069b4
--- /dev/null
+++ b/internal/github/filesystem.go
@@ -0,0 +1,63 @@
+package github
+
+import (
+	"fmt"
+	"net/url"
+	"os"
+	"path"
+	"strings"
+)
+
+func listReleasesByTagName(dst *url.URL) ([]string, error) {
+	entries, err := os.ReadDir(dst.Path)
+	if err != nil {
+		return nil, err
+	}
+
+	var tagNames []string
+	for _, entry := range entries {
+		tagNames = append(tagNames, entry.Name())
+	}
+
+	return tagNames, nil
+}
+
+// The path which project release assets are saved.
+func localReleaseFilePath(dst *url.URL, tagName string) string {
+	return path.Join(dst.Path, tagName)
+}
+
+func releaseName(tagName string) string {
+	version := tagName
+	if strings.HasPrefix(version, "v") {
+		version = strings.TrimLeft(version, "v")
+	}
+
+	return version
+}
+
+// The source filename for a Github release.
+//
+// # The source code URL provided by Github's API only references the tag name
+//
+// for the release.  To make it useful for users, we rename to file to include
+// the project name as their website does.
+func releaseSourceFileName(project string, tagName string, ext string) string {
+	return fmt.Sprintf("%s-%s.%s", project, releaseName(tagName), ext)
+}
+
+func removeRelease(dst *url.URL, tagName string) error {
+	fp := localReleaseFilePath(dst, tagName)
+	return os.RemoveAll(fp)
+}
+
+func isFileExist(fp string) (bool, error) {
+	_, err := os.Stat(fp)
+	if os.IsNotExist(err) {
+		return false, nil
+	} else if err != nil {
+		return false, err
+	}
+
+	return true, nil
+}