feat: Waku v2 bridge

Issue #12610

vendor/github.com/libp2p/go-libp2p-pubsub/timecache/time_cache.go

@@ -0,0 +1,52 @@
+package timecache
+
+import (
+	"time"
+
+	logger "github.com/ipfs/go-log/v2"
+)
+
+var log = logger.Logger("pubsub/timecache")
+
+// Stategy is the TimeCache expiration strategy to use.
+type Strategy uint8
+
+const (
+	// Strategy_FirstSeen expires an entry from the time it was added.
+	Strategy_FirstSeen Strategy = iota
+	// Stategy_LastSeen expires an entry from the last time it was touched by an Add or Has.
+	Strategy_LastSeen
+)
+
+// TimeCache is a cahe of recently seen messages (by id).
+type TimeCache interface {
+	// Add adds an id into the cache, if it is not already there.
+	// Returns true if the id was newly added to the cache.
+	// Depending on the implementation strategy, it may or may not update the expiry of
+	// an existing entry.
+	Add(string) bool
+	// Has checks the cache for the presence of an id.
+	// Depending on the implementation strategy, it may or may not update the expiry of
+	// an existing entry.
+	Has(string) bool
+	// Done signals that the user is done with this cache, which it may stop background threads
+	// and relinquish resources.
+	Done()
+}
+
+// NewTimeCache defaults to the original ("first seen") cache implementation
+func NewTimeCache(ttl time.Duration) TimeCache {
+	return NewTimeCacheWithStrategy(Strategy_FirstSeen, ttl)
+}
+
+func NewTimeCacheWithStrategy(strategy Strategy, ttl time.Duration) TimeCache {
+	switch strategy {
+	case Strategy_FirstSeen:
+		return newFirstSeenCache(ttl)
+	case Strategy_LastSeen:
+		return newLastSeenCache(ttl)
+	default:
+		// Default to the original time cache implementation
+		return newFirstSeenCache(ttl)
+	}
+}