metrics

const (
	// INVITE responses, classified by direction and response class.
	// One series per (direction, class) — bounded to 2 × 6 = 12 series.
	MetricInviteResultTotal = "sip_invite_result_total"

	// BYE events, classified by who initiated and reason class.
	MetricByeTotal = "sip_bye_total"

	// Transaction-level timeouts (timer F / B fired, RFC 3261).
	MetricTransactionTimeoutTotal = "sip_transaction_timeout_total"

	// RFC 4028 session-timer refresher events. result = ok / 422 /
	// 481 / role-swap / gave-up.
	MetricSessionTimerRefreshTotal = "sip_session_timer_refresh_total"

	// DTLS-SRTP handshake outcomes. result = ok / fail / timeout /
	// fingerprint-mismatch.
	MetricDTLSHandshakeTotal = "sip_dtls_handshake_total"

	// RFC 8224 STIR verification outcomes.
	MetricSTIRVerifyTotal = "sip_stir_verify_total"

	// RTCP-derived per-call QoS roll-ups, recorded ONCE at call end.
	MetricCallRTTMs        = "sip_call_rtt_ms"
	MetricCallJitterMs     = "sip_call_jitter_ms"
	MetricCallLossFraction = "sip_call_loss_fraction"
	MetricCallMOSEstimate  = "sip_call_mos_estimate"
)

const (
	DirectionInbound  = "inbound"
	DirectionOutbound = "outbound"
)

const (
	ByeByLocal  = "local"
	ByeByRemote = "remote"

	// Reason classes — bounded enum.
	ByeReasonNormal       = "normal"        // 200 OK BYE no special cause
	ByeReasonTimerExpired = "timer-expired" // RFC 4028 session-timer expired
	ByeReasonError        = "error"         // unexpected (pipeline failure, etc.)
	ByeReasonUserHangup   = "user-hangup"   // explicit hangup intent
)

const (
	RefreshResultOK         = "ok"          // peer accepted with 200
	Refresh422Bumped        = "422-bumped"  // got 422, retried with peer Min-SE
	Refresh422GaveUp        = "422-gave-up" // second 422, stopped
	Refresh481DialogGone    = "481"         // dialog disappeared
	RefreshRoleSwappedToUAS = "role-swap"   // peer flipped refresher to itself
)

const (
	DTLSResultOK                  = "ok"
	DTLSResultFail                = "fail"
	DTLSResultTimeout             = "timeout"
	DTLSResultFingerprintMismatch = "fingerprint-mismatch"
)

const (
	STIRResultVerified = "verified"
	STIRResultFailed   = "failed"
	STIRResultSoftFail = "soft-fail" // verifier rejected but call continued
	STIRResultNoIdent  = "no-identity"
)

const (
	// MetricVoiceAttachTotal counts voice-attach attempts at the OnACK
	// seam, classified by resolved engine.Mode and final outcome.
	//
	// labels:
	//   mode   = "cascaded" | "realtime"
	//   result = "ok" | "config_error"
	//
	// "config_error" is the umbrella for every failure path that
	// played scripts/config_error.wav (no tenant id, env load error,
	// missing/incomplete credentials). Granular reasons live in the
	// log lines emitted by AttachCascadedLegacy / AttachRealtimeLegacy;
	// they're not labels because the cardinality blows up fast.
	MetricVoiceAttachTotal = "sip_voice_attach_total"

	// MetricVoiceAttachModeFallbackTotal counts implicit mode
	// fallbacks made by ResolveAttachMode (today: tenant persisted
	// voice_mode="pipeline" but pipeline creds are unusable and
	// realtime is ready → we auto-select realtime).
	//
	// labels:
	//   from = "pipeline"
	//   to   = "realtime"
	MetricVoiceAttachModeFallbackTotal = "sip_voice_attach_mode_fallback_total"

	// MetricVoiceAttachNativeTotal counts decisions made by the
	// PR-9d feature flag to route a cascaded call through the
	// native cascaded.Engine (engine.ModeCascadedNative) instead of
	// the legacy bridge. Independent from MetricVoiceAttachTotal so
	// dashboards can monitor opt-in rollout without churn-affecting
	// the existing per-mode chart.
	//
	// labels:
	//   result = "ok" | "err"
	MetricVoiceAttachNativeTotal = "sip_voice_attach_native_total"
)

const (
	VoiceAttachModeCascaded = "cascaded"
	VoiceAttachModeRealtime = "realtime"
)

const (
	VoiceAttachResultOK          = "ok"
	VoiceAttachResultConfigError = "config_error"
)