package bot

import "net/http"

// SidecarHeader marks every request the live sidecar makes to its instance —
// the WebSocket dial and all REST calls — so a hibernation-aware router
// (activator.go) can tell sidecar traffic from member traffic. A co-spawned
// sidecar's connections flow through its own instance's router (the box pins
// its hosted names to loopback), and without the marker its keepalives would
// read as member activity: the instance could never idle, and after a sleep
// the reconnect loop would be a standing wake source. Marked requests are
// served while the instance is awake but stamp no activity, and never wake a
// sleeping one.
//
// The marker is deliberately spoofable-but-harmless: it only DOWNGRADES the
// sender's own requests (no activity credit; 503 while the instance sleeps).
// It cannot suppress other clients' activity stamps and cannot wake anything,
// so an outsider sending it gains nothing. Provisioning (provision.go) stays
// unmarked on purpose — claiming an invite is an operator action and should
// behave like a person's request.
const SidecarHeader = "X-Lchat-Sidecar"

// markTransport stamps SidecarHeader on every request — the Runtime's HTTP
// client uses it so no REST call site can forget the marker. It clones the
// request first, per the RoundTripper contract.
type markTransport struct{}

func (markTransport) RoundTrip(req *http.Request) (*http.Response, error) {
	req = req.Clone(req.Context())
	req.Header.Set(SidecarHeader, "1")
	return http.DefaultTransport.RoundTrip(req)
}