feat: Waku v2 bridge

Issue #12610

vendor/github.com/anacrolix/missinggo/httptoo/headers.go

@@ -0,0 +1,61 @@
+package httptoo
+
+import (
+	"fmt"
+	"strings"
+	"time"
+)
+
+type Visibility int
+
+const (
+	Default = 0
+	Public  = 1
+	Private = 2
+)
+
+type CacheControlHeader struct {
+	MaxAge  time.Duration
+	Caching Visibility
+	NoStore bool
+}
+
+func (me *CacheControlHeader) caching() []string {
+	switch me.Caching {
+	case Public:
+		return []string{"public"}
+	case Private:
+		return []string{"private"}
+	default:
+		return nil
+	}
+}
+
+func (me *CacheControlHeader) maxAge() []string {
+	if me.MaxAge == 0 {
+		return nil
+	}
+	d := me.MaxAge
+	if d < 0 {
+		d = 0
+	}
+	return []string{fmt.Sprintf("max-age=%d", d/time.Second)}
+}
+
+func (me *CacheControlHeader) noStore() []string {
+	if me.NoStore {
+		return []string{"no-store"}
+	}
+	return nil
+}
+
+func (me *CacheControlHeader) concat(sss ...[]string) (ret []string) {
+	for _, ss := range sss {
+		ret = append(ret, ss...)
+	}
+	return
+}
+
+func (me CacheControlHeader) String() string {
+	return strings.Join(me.concat(me.caching(), me.maxAge()), ", ")
+}