Refactor git attributes (#29356)

modules/git/repo_language_stats.go

@@ -6,6 +6,8 @@ package git
 import (
 	"strings"
 	"unicode"
+
+	"code.gitea.io/gitea/modules/optional"
 )
 
 const (
@@ -46,3 +48,20 @@ func mergeLanguageStats(stats map[string]int64) map[string]int64 {
 	}
 	return res
 }
+
+func TryReadLanguageAttribute(attrs map[string]string) optional.Option[string] {
+	language := AttributeToString(attrs, AttributeLinguistLanguage)
+	if language.Value() == "" {
+		language = AttributeToString(attrs, AttributeGitlabLanguage)
+		if language.Has() {
+			raw := language.Value()
+			// gitlab-language may have additional parameters after the language
+			// ignore them and just use the main language
+			// https://docs.gitlab.com/ee/user/project/highlighting.html#override-syntax-highlighting-for-a-file-type
+			if idx := strings.IndexByte(raw, '?'); idx >= 0 {
+				language = optional.Some(raw[:idx])
+			}
+		}
+	}
+	return language
+}