protocol

const (
	// CloseClientShutdown identifies an intentional client process shutdown.
	CloseClientShutdown CloseReason = 1
)

const (
	// ErrorRetryable identifies a temporary transport or capacity failure.
	ErrorRetryable ErrorClass = iota + 1
	// ErrorLaneRejected identifies a terminal rejection scoped to one lane candidate.
	ErrorLaneRejected
	// ErrorSessionGone identifies a session that no longer exists on the server.
	ErrorSessionGone
	// ErrorSessionRejected identifies a terminal rejection of the authenticated session.
	ErrorSessionRejected
)

const (
	// ErrorMalformed identifies malformed handshake or frame input.
	ErrorMalformed ErrorCode = iota + 1
	// ErrorUnsupportedVersion identifies an incompatible wire protocol version.
	ErrorUnsupportedVersion
	// ErrorAuthentication identifies invalid authentication material.
	ErrorAuthentication
	// ErrorReplay identifies a reused authenticated handshake nonce.
	ErrorReplay
	// ErrorTargetDenied identifies a target outside server policy.
	ErrorTargetDenied
	// ErrorSessionNotFound identifies an unknown or expired session.
	ErrorSessionNotFound
	// ErrorStaleGeneration identifies a non-increasing lane connection generation.
	ErrorStaleGeneration
	// ErrorLaneLimit identifies a per-session lane limit.
	ErrorLaneLimit
	// ErrorSessionLimit identifies a server session limit.
	ErrorSessionLimit
	// ErrorProtocolViolation identifies invalid in-session behavior.
	ErrorProtocolViolation
	// ErrorUnavailable identifies a temporary server or target failure.
	ErrorUnavailable
	// ErrorRateLimited identifies a temporary admission or reconnect rate limit.
	ErrorRateLimited
	// ErrorInternal identifies an unexpected server failure.
	ErrorInternal
	// ErrorClockSkew identifies an authenticated timestamp outside the server's acceptance window.
	ErrorClockSkew
)

const (
	// ErrorScopeLane limits an error to one lane generation.
	ErrorScopeLane ErrorScope = iota + 1
	// ErrorScopeSession applies an error to the complete session.
	ErrorScopeSession
)

const (
	// FrameData carries one WireGuard UDP datagram.
	FrameData FrameType = iota + 1
	// FramePing requests a lane timing response.
	FramePing
	// FramePong responds to a lane timing request.
	FramePong
	// FrameClockSync updates the shared session clock mapping.
	FrameClockSync
	// FrameProbe measures lane delivery behavior without reaching the UDP target.
	FrameProbe
	// FrameDeliveryReport reports cumulative peer parsing progress.
	FrameDeliveryReport
	// FrameSessionCreated accepts a newly created session.
	FrameSessionCreated
	// FrameLaneAccepted accepts a lane joined to an existing session.
	FrameLaneAccepted
	// FrameSessionClose explicitly closes a session.
	FrameSessionClose
	// FrameLaneAbandon coordinates generation-specific connection abandonment.
	FrameLaneAbandon
	// FrameError reports an in-session protocol or policy error.
	FrameError
)

const (
	// HelloCreate creates a new authenticated session and its first lane.
	HelloCreate HelloMode = iota + 1
	// HelloJoin joins a new connection generation to an existing session.
	HelloJoin
)

const (
	// ServerSessionCreated accepts a newly created session.
	ServerSessionCreated ServerHelloResult = iota + 1
	// ServerLaneAccepted accepts a joined lane connection generation.
	ServerLaneAccepted
	// ServerRejected rejects the client hello with a stable protocol error.
	ServerRejected
)