1 files changed, 67 insertions, 0 deletions
diff --git a/modules/git/signature.go b/modules/git/signature.go
new file mode 100644
index 0000000..c368ce3
--- /dev/null
+++ b/modules/git/signature.go
@@ -0,0 +1,67 @@
+// Copyright 2015 The Gogs Authors. All rights reserved.
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package git
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+	"time"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/util"
+)
+
+// Signature represents the Author, Committer or Tagger information.
+type Signature struct {
+	Name  string    // the committer name, it can be anything
+	Email string    // the committer email, it can be anything
+	When  time.Time // the timestamp of the signature
+}
+
+func (s *Signature) String() string {
+	return fmt.Sprintf("%s <%s>", s.Name, s.Email)
+}
+
+// Decode decodes a byte array representing a signature to signature
+func (s *Signature) Decode(b []byte) {
+	*s = *parseSignatureFromCommitLine(util.UnsafeBytesToString(b))
+}
+
+// Helper to get a signature from the commit line, which looks like:
+//
+//	full name <user@example.com> 1378823654 +0200
+//
+// Haven't found the official reference for the standard format yet.
+// This function never fails, if the "line" can't be parsed, it returns a default Signature with "zero" time.
+func parseSignatureFromCommitLine(line string) *Signature {
+	sig := &Signature{}
+	s1, sx, ok1 := strings.Cut(line, " <")
+	s2, s3, ok2 := strings.Cut(sx, "> ")
+	if !ok1 || !ok2 {
+		sig.Name = line
+		return sig
+	}
+	sig.Name, sig.Email = s1, s2
+
+	if strings.Count(s3, " ") == 1 {
+		ts, tz, _ := strings.Cut(s3, " ")
+		seconds, _ := strconv.ParseInt(ts, 10, 64)
+		if tzTime, err := time.Parse("-0700", tz); err == nil {
+			sig.When = time.Unix(seconds, 0).In(tzTime.Location())
+		}
+	} else {
+		// the old gitea code tried to parse the date in a few different formats, but it's not clear why.
+		// according to public document, only the standard format "timestamp timezone" could be found, so drop other formats.
+		log.Error("suspicious commit line format: %q", line)
+		for _, fmt := range []string{ /*"Mon Jan _2 15:04:05 2006 -0700"*/ } {
+			if t, err := time.Parse(fmt, s3); err == nil {
+				sig.When = t
+				break
+			}
+		}
+	}
+	return sig
+}