session

type AdmissionQueue interface {
	// TryAdmit attempts to admit a request. If the queue is open, it returns
	// (true, done) where done must be called when the request completes.
	// If the queue is already closed, it returns (false, nil).
	TryAdmit() (bool, func())

	// CloseAndDrain closes the queue so that subsequent TryAdmit calls return
	// false, then blocks until all currently-admitted requests have called
	// their done function. Idempotent.
	CloseAndDrain()
}

type MultiSession = sessiontypes.MultiSession

type MultiSessionFactory interface {
	// MakeSession creates a new MultiSession for the given identity against the
	// provided set of backends. Backend clients are initialised in parallel
	// with bounded concurrency (see WithMaxBackendInitConcurrency).
	//
	// Partial initialisation: if a backend fails to initialise, a warning is
	// logged and the session continues with the remaining backends. The caller
	// receives a valid session as long as at least one backend succeeded.
	//
	// If all backends fail, MakeSession still returns a valid (empty) session
	// rather than an error, allowing clients to connect even when all backends
	// are temporarily unavailable.
	//
	// TODO(sessionManagementV2): MakeSession is only used by tests for convenience
	// (auto-generates UUID). Production code uses MakeSessionWithID exclusively.
	// This method can be removed once the sessionManagementV2 migration is complete
	// and VMCPSession is deleted. Tests can be updated to generate their own UUIDs.
	MakeSession(ctx context.Context, identity *auth.Identity, backends []*vmcp.Backend) (MultiSession, error)

	// MakeSessionWithID creates a new MultiSession with a specific session ID.
	// This is used by SessionManager to create sessions using the SDK-assigned ID
	// rather than generating a new UUID internally.
	//
	// The id parameter must be non-empty and should be a valid MCP session ID
	// (visible ASCII characters, 0x21 to 0x7E per the MCP specification).
	//
	// The allowAnonymous parameter controls whether the session allows nil caller
	// identity. If false, all session method calls must provide a valid caller
	// that matches the session creator's identity.
	//
	// All other behaviour (partial initialisation, bounded concurrency, etc.)
	// is identical to MakeSession.
	MakeSessionWithID(
		ctx context.Context,
		id string,
		identity *auth.Identity,
		allowAnonymous bool,
		backends []*vmcp.Backend,
	) (MultiSession, error)
}

type MultiSessionFactoryOption func(*defaultMultiSessionFactory)

type VMCPSession struct {
	*transportsession.StreamableSession
	// contains filtered or unexported fields
}