1 files changed, 112 insertions, 0 deletions
diff --git a/cmd/generate/forge_gerrit.go b/cmd/generate/forge_gerrit.go
new file mode 100644
index 0000000..6bdeece
--- /dev/null
+++ b/cmd/generate/forge_gerrit.go
@@ -0,0 +1,112 @@
+package main
+
+import (
+	"encoding"
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"strings"
+	"time"
+)
+
+// httpGetGerritJSON is like [httpGetJSON], but
+// https://gerrit-review.googlesource.com/Documentation/rest-api.html#output
+func httpGetGerritJSON(u string, hdr map[string]string, out any) error {
+	str, err := httpGet(u, hdr)
+	if err != nil {
+		return err
+	}
+	if _, body, ok := strings.Cut(str, "\n"); ok {
+		str = body
+	}
+	return json.Unmarshal([]byte(str), out)
+}
+
+const GerritTimeFormat = "2006-01-02 15:04:05.000000000"
+
+type GerritTime struct {
+	Val time.Time
+}
+
+var (
+	_ fmt.Stringer             = GerritTime{}
+	_ encoding.TextMarshaler   = GerritTime{}
+	_ encoding.TextUnmarshaler = (*GerritTime)(nil)
+)
+
+// String implements [fmt.Stringer].
+func (t GerritTime) String() string {
+	return t.Val.Format(GerritTimeFormat)
+}
+
+// MarshalText implements [encoding.TextMarshaler].
+func (t GerritTime) MarshalText() ([]byte, error) {
+	return []byte(t.String()), nil
+}
+
+// UnmarshalText implements [encoding.TextUnmarshaler].
+func (t *GerritTime) UnmarshalText(data []byte) error {
+	val, err := time.Parse(GerritTimeFormat, string(data))
+	if err != nil {
+		return err
+	}
+	t.Val = val
+	return nil
+}
+
+type Gerrit struct{}
+
+var _ Forge = Gerrit{}
+
+func (Gerrit) FetchStatus(urls []string) (string, error) {
+	return "", nil
+}
+
+func (Gerrit) FetchSubmittedAt(urls []string) (time.Time, error) {
+	return time.Time{}, nil
+}
+
+var reGoLangGerritCL = regexp.MustCompile(`https://go-review\.googlesource\.com/c/([^/?#]+)/\+/([0-9]+)(?:\?[^#]*)?(?:#.*)?$`)
+
+func (Gerrit) FetchLastUpdated(urls []string) (time.Time, User, error) {
+	for _, u := range urls {
+		m := reGoLangGerritCL.FindStringSubmatch(u)
+		if m == nil {
+			continue
+		}
+		projectID := m[1]
+		changeID := m[2]
+
+		urlStr := "https://go-review.googlesource.com/changes/" + projectID + "~" + changeID + "?o=MESSAGES&o=DETAILED_ACCOUNTS"
+
+		var obj struct {
+			Updated  GerritTime `json:"updated"`
+			Messages []struct {
+				Author struct {
+					AccountID   int    `json:"_account_id"`
+					Name        string `json:"name"`
+					DisplayName string `json:"display_name"`
+				} `json:"author"`
+				Date GerritTime `json:"date"`
+			} `json:"messages"`
+		}
+		if err := httpGetGerritJSON(urlStr, nil, &obj); err != nil {
+			return time.Time{}, User{}, err
+		}
+		retUpdatedAt := obj.Updated.Val
+		var retUser User
+		for _, message := range obj.Messages {
+			if withinOneSecond(message.Date.Val, retUpdatedAt) {
+				if message.Author.DisplayName != "" {
+					retUser.Name = message.Author.DisplayName
+				} else {
+					retUser.Name = message.Author.Name
+				}
+				retUser.URL = fmt.Sprintf("https://go-review.googlesource.com/dashboard/%d", message.Author.AccountID)
+				break
+			}
+		}
+		return retUpdatedAt, retUser, nil
+	}
+	return time.Time{}, User{}, nil
+}