sdk: event access time kv helpers.

sdk/event_access_time.go

@@ -0,0 +1,51 @@
+package sdk
+
+import (
+	"encoding/binary"
+
+	"fiatjaf.com/nostr"
+)
+
+const eventAccessTimePrefix = byte('a')
+
+// makeEventAccessTimeKey creates a key for storing event access time information.
+// It uses the first 8 bytes of the event ID to create a compact key.
+func makeEventAccessTimeKey(id nostr.ID) []byte {
+	// format: 'a' + first 8 bytes of event ID
+	key := make([]byte, 9)
+	key[0] = eventAccessTimePrefix
+	copy(key[1:], id[:8])
+	return key
+}
+
+// encodeEventAccessTime serializes an EventAccessTime into a binary format.
+func encodeEventAccessTime(t nostr.Timestamp) []byte {
+	buf := make([]byte, 8)
+	binary.BigEndian.PutUint64(buf[0:8], uint64(t))
+	return buf
+}
+
+// decodeEventAccessTime deserializes a binary-encoded EventAccessTime.
+func decodeEventAccessTime(data []byte) nostr.Timestamp {
+	return nostr.Timestamp(binary.BigEndian.Uint64(data[0:8]))
+}
+
+// trackEventAccessTime records the access time for an event.
+func (sys *System) TrackEventAccessTime(id nostr.ID) {
+	key := makeEventAccessTimeKey(id)
+	sys.KVStore.Update(key, func(data []byte) ([]byte, error) {
+		return encodeEventAccessTime(nostr.Now()), nil
+	})
+}
+
+// GetEventAccessTime returns the access times for an event.
+func (sys *System) GetEventAccessTime(id nostr.ID) nostr.Timestamp {
+	key := makeEventAccessTimeKey(id)
+
+	data, _ := sys.KVStore.Get(key)
+	if data == nil {
+		return 0
+	}
+
+	return decodeEventAccessTime(data)
+}