nip34: repository state and some ToEvent() helpers.

nip34/state.go

@@ -0,0 +1,64 @@
+package nip34
+
+import (
+	"strings"
+
+	"github.com/nbd-wtf/go-nostr"
+)
+
+type RepositoryState struct {
+	nostr.Event
+
+	ID       string
+	HEAD     string
+	Tags     map[string]string
+	Branches map[string]string
+}
+
+func ParseRepositoryState(event nostr.Event) RepositoryState {
+	st := RepositoryState{
+		Event:    event,
+		Tags:     make(map[string]string),
+		Branches: make(map[string]string),
+	}
+
+	for _, tag := range event.Tags {
+		if len(tag) < 2 {
+			continue
+		}
+		switch tag[0] {
+		case "d":
+			st.ID = tag[1]
+		case "HEAD":
+			if strings.HasPrefix(tag[1], "ref: refs/heads/") {
+				st.HEAD = tag[1][16:]
+			}
+		default:
+			if strings.HasPrefix(tag[0], "refs/heads/") {
+				st.Branches[tag[0][11:]] = tag[1]
+			} else if strings.HasPrefix(tag[0], "refs/tags/") {
+				st.Branches[tag[0][10:]] = tag[1]
+			}
+		}
+	}
+
+	return st
+}
+
+func (rs RepositoryState) ToEvent() nostr.Event {
+	tags := make(nostr.Tags, 0, 2+len(rs.Branches)+len(rs.Tags))
+
+	tags = append(tags, nostr.Tag{"d", rs.ID})
+	tags = append(tags, nostr.Tag{"ref: refs/heads/" + rs.HEAD})
+	for branchName, commitId := range rs.Branches {
+		tags = append(tags, nostr.Tag{"refs/heads/" + branchName, commitId})
+	}
+	for tagName, commitId := range rs.Tags {
+		tags = append(tags, nostr.Tag{"refs/tags/" + tagName, commitId})
+	}
+
+	return nostr.Event{
+		Kind: 30618,
+		Tags: tags,
+	}
+}