package implementationhost

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"net/url"
	"strings"
	"sync"
	"time"
	"unicode/utf8"

	agentruntime "github.com/tutti-os/tutti/packages/agent/daemon/runtime"
	market "github.com/tutti-os/tutti/packages/connector/daemon/core"
	connectorruntime "github.com/tutti-os/tutti/packages/connector/runtime"
)

const credentialBrokerInitialEventTimeout = 30 * time.Second
const credentialBrokerContinuationWait = time.Second

type managedCLILaunch struct {
	arguments     []string
	artifactTrees []agentruntime.ArtifactTreeIdentity
	cwd           string
	executable    connectorruntime.ConnectorExecutable
	language      string
	stateDir      string
	timeout       time.Duration
}

type credentialBrokerCLILaunch struct {
	Executable string   `json:"executable"`
	Arguments  []string `json:"arguments"`
	CWD        string   `json:"cwd"`
}

type managedCredentialBrokerLaunch struct {
	entrypoint    string
	timeout       time.Duration
	allowedHosts  map[string]struct{}
	cliLaunch     credentialBrokerCLILaunch
	executable    connectorruntime.ConnectorExecutable
	language      string
	cwd           string
	artifactTrees []agentruntime.ArtifactTreeIdentity
	stateDir      string
}

type managedCredentialAuthorizationHost interface {
	authorizationRoute(context.Context, market.OperationScope, market.Connector) (*connectorRoute, error)
	startCredentialBroker(context.Context, *connectorRoute, credentialBrokerRequest) (agentruntime.ProcessConnection, uint64, error)
	observeAuthorization(*connectorRoute, market.AuthorizationState)
	releaseAuthorizationRoute(*connectorRoute)
}

// managedCredentialAuthorizationProvider owns the host-side lifecycle of a
// connector-provided credential broker. Provider-specific commands, response
// parsing, and secret handoffs stay inside the verified connector adapter.
type managedCredentialAuthorizationProvider struct {
	host          managedCredentialAuthorizationHost
	mu            sync.Mutex
	sessions      map[string]*credentialBrokerSession
	activeByRoute map[string]string
}

type credentialBrokerRequest struct {
	Protocol  string `json:"protocol"`
	Operation string `json:"operation"`
}

type credentialBrokerEvent struct {
	Type    string `json:"type"`
	URL     string `json:"url,omitempty"`
	Code    string `json:"code,omitempty"`
	Message string `json:"message,omitempty"`
}

type credentialBrokerSession struct {
	operationID string
	route       *connectorRoute
	connection  agentruntime.ProcessConnection
	cancel      context.CancelFunc
	done        chan struct{}

	mu       sync.Mutex
	state    market.AuthorizationState
	url      string
	userCode string
	err      error
	version  uint64
	hasEvent bool
	changed  chan struct{}
}

func newManagedCredentialAuthorizationProvider(host managedCredentialAuthorizationHost) *managedCredentialAuthorizationProvider {
	return &managedCredentialAuthorizationProvider{
		host: host, sessions: make(map[string]*credentialBrokerSession), activeByRoute: make(map[string]string),
	}
}

func (host *Host) BeginAuthorization(ctx context.Context, request market.AuthorizationStartRequest) (market.AuthorizationSession, error) {
	if host == nil || host.authorizationProvider == nil {
		return market.AuthorizationSession{}, errors.New("connector authorization provider is unavailable")
	}
	return host.authorizationProvider.Begin(ctx, request)
}

func (host *Host) DisconnectAuthorization(ctx context.Context, request market.AuthorizationDisconnectRequest) error {
	if host == nil || host.authorizationProvider == nil {
		return errors.New("connector authorization provider is unavailable")
	}
	return host.authorizationProvider.Disconnect(ctx, request)
}

func (host *Host) CancelAuthorization(ctx context.Context, request market.AuthorizationCancelRequest) error {
	if host == nil || host.authorizationProvider == nil {
		return errors.New("connector authorization provider is unavailable")
	}
	return host.authorizationProvider.Cancel(ctx, request)
}

func (host *Host) InspectAuthorization(ctx context.Context, request market.AuthorizationInspectRequest) (market.AuthorizationObservation, error) {
	if host == nil || host.authorizationProvider == nil {
		return market.AuthorizationObservation{}, errors.New("connector authorization inspector is unavailable")
	}
	return host.authorizationProvider.Inspect(ctx, request)
}

func (provider *managedCredentialAuthorizationProvider) Begin(
	ctx context.Context,
	request market.AuthorizationStartRequest,
) (market.AuthorizationSession, error) {
	connector := request.Connector
	connector.Release = request.Release
	route, err := provider.host.authorizationRoute(ctx, request.Scope, connector)
	if err != nil {
		return market.AuthorizationSession{}, err
	}
	session, err := provider.authorizationSessionOrStart(route, request.OperationID, request.StepRevisionBase)
	if err != nil {
		return market.AuthorizationSession{}, err
	}
	if err := session.awaitEventAfter(ctx, request.AfterStepRevision); err != nil {
		cleanupContext, cancelCleanup := context.WithTimeout(context.Background(), 5*time.Second)
		cleanupErr := provider.cancelAuthorizationSession(cleanupContext, session)
		cancelCleanup()
		return market.AuthorizationSession{}, errors.Join(err, cleanupErr)
	}
	state, authorizationURL, userCode, stepRevision, sessionErr := session.snapshot()
	if sessionErr != nil {
		provider.clearAuthorizationSession(request.OperationID, session)
		provider.host.releaseAuthorizationRoute(route)
		return market.AuthorizationSession{}, sessionErr
	}
	result := market.AuthorizationSession{
		OperationID:      request.OperationID,
		ConnectorKey:     request.Connector.Key,
		ConnectionID:     route.connectionID,
		SessionID:        request.OperationID + "/credential-broker",
		AuthorizationURL: authorizationURL,
		UserCode:         userCode,
		StepRevision:     stepRevision,
		State:            state,
	}
	if state == market.AuthorizationStateConnected {
		provider.clearAuthorizationSession(request.OperationID, session)
		provider.host.releaseAuthorizationRoute(route)
	}
	return result, nil
}

func (provider *managedCredentialAuthorizationProvider) Cancel(
	ctx context.Context,
	request market.AuthorizationCancelRequest,
) error {
	provider.mu.Lock()
	session := provider.sessions[strings.TrimSpace(request.OperationID)]
	provider.mu.Unlock()
	if session == nil {
		return nil
	}
	return provider.cancelAuthorizationSession(ctx, session)
}

func (provider *managedCredentialAuthorizationProvider) Disconnect(
	ctx context.Context,
	request market.AuthorizationDisconnectRequest,
) error {
	route, err := provider.host.authorizationRoute(ctx, request.Scope, request.Connector)
	if err != nil {
		return err
	}
	if session := provider.takeAuthorizationSessionByRoute(route.id); session != nil {
		session.cancel()
		select {
		case <-session.done:
		case <-ctx.Done():
			return ctx.Err()
		}
	}
	operationContext, cancel := context.WithTimeout(ctx, route.credentialBrokerLaunch.timeout)
	defer cancel()
	connection, processID, err := provider.host.startCredentialBroker(operationContext, route, credentialBrokerRequest{
		Protocol: market.CredentialBrokerProtocolV1, Operation: "disconnect",
	})
	if err != nil {
		return fmt.Errorf("start connector credential broker disconnect: %w", err)
	}
	defer func() { _ = route.releaseProcess(processID, connection) }()
	event, err := readCredentialBrokerTerminalEvent(operationContext, connection)
	if err != nil {
		return fmt.Errorf("disconnect connector authorization: %w", err)
	}
	if event.Type != "disconnected" {
		return credentialBrokerEventError(event, "disconnect")
	}
	provider.host.observeAuthorization(route, market.AuthorizationStateDisconnected)
	provider.host.releaseAuthorizationRoute(route)
	return nil
}

func (provider *managedCredentialAuthorizationProvider) Inspect(
	ctx context.Context,
	request market.AuthorizationInspectRequest,
) (market.AuthorizationObservation, error) {
	route, err := provider.host.authorizationRoute(ctx, request.Scope, request.Connector)
	if err != nil {
		return market.AuthorizationObservation{}, err
	}
	operationContext, cancel := context.WithTimeout(ctx, route.credentialBrokerLaunch.timeout)
	defer cancel()
	connection, processID, err := provider.host.startCredentialBroker(operationContext, route, credentialBrokerRequest{
		Protocol: market.CredentialBrokerProtocolV1, Operation: "inspect",
	})
	if err != nil {
		return market.AuthorizationObservation{}, fmt.Errorf("start connector credential broker inspect: %w", err)
	}
	defer func() { _ = route.releaseProcess(processID, connection) }()
	event, err := readCredentialBrokerInspectionEvent(operationContext, connection)
	if err != nil {
		return market.AuthorizationObservation{}, fmt.Errorf("inspect connector authorization: %w", err)
	}
	var state market.AuthorizationObservationState
	switch event.Type {
	case "connected":
		state = market.AuthorizationObservationConnected
	case "disconnected":
		state = market.AuthorizationObservationDisconnected
	case "expired":
		state = market.AuthorizationObservationExpired
	case "error":
		state = market.AuthorizationObservationFailed
	default:
		return market.AuthorizationObservation{}, fmt.Errorf("connector credential broker returned unsupported inspect event %q", event.Type)
	}
	connector := request.Connector
	return market.AuthorizationObservation{
		AccountID: request.Scope.AccountID, AccountGeneration: request.AccountGeneration,
		VMAssignmentID: request.VMAssignmentID, ConnectorKey: connector.Key, ConnectionID: route.connectionID,
		ReleaseDigest: connector.Release.ReleaseDigest, AuthorizationSessionID: request.AuthorizationSessionID,
		AuthorizationGeneration: request.AuthorizationGeneration, DesktopBootEpoch: request.DesktopBootEpoch,
		GuestBootID: request.GuestBootID, RuntimeEpoch: request.RuntimeEpoch, StateRevision: request.StateRevision,
		State: state, Reason: strings.TrimSpace(event.Message), FailureCode: strings.TrimSpace(event.Code), ObservedAt: time.Now().UTC(),
	}, nil
}

func (provider *managedCredentialAuthorizationProvider) authorizationSessionOrStart(
	route *connectorRoute,
	operationID string,
	stepRevisionBase uint64,
) (*credentialBrokerSession, error) {
	operationID = strings.TrimSpace(operationID)
	provider.mu.Lock()
	if session := provider.sessions[operationID]; session != nil {
		_, _, _, _, sessionErr := session.snapshot()
		if sessionErr == nil {
			provider.mu.Unlock()
			return session, nil
		}
		// A broker can fail after emitting its first authorization URL. Do not
		// make the next user action consume that terminal error merely to clear
		// the cache; replace it with a fresh broker in this same request.
		delete(provider.sessions, operationID)
		if provider.activeByRoute[route.id] == operationID {
			delete(provider.activeByRoute, route.id)
		}
	}
	if activeOperationID := provider.activeByRoute[route.id]; activeOperationID != "" {
		active := provider.sessions[activeOperationID]
		if active != nil {
			_, _, _, _, activeErr := active.snapshot()
			if activeErr != nil {
				select {
				case <-active.done:
					delete(provider.sessions, activeOperationID)
					delete(provider.activeByRoute, route.id)
				default:
					provider.mu.Unlock()
					return nil, errors.New("connector credential broker termination is still pending")
				}
			} else {
				provider.mu.Unlock()
				return nil, errors.New("connector credential broker has an active authorization attempt")
			}
		} else {
			delete(provider.activeByRoute, route.id)
		}
	}
	processContext, cancel := context.WithTimeout(context.Background(), route.credentialBrokerLaunch.timeout)
	connection, processID, err := provider.host.startCredentialBroker(processContext, route, credentialBrokerRequest{
		Protocol: market.CredentialBrokerProtocolV1, Operation: "begin",
	})
	if err != nil {
		cancel()
		provider.mu.Unlock()
		return nil, fmt.Errorf("start connector credential broker: %w", err)
	}
	session := &credentialBrokerSession{
		operationID: operationID, route: route, connection: connection, cancel: cancel,
		done: make(chan struct{}), version: stepRevisionBase, changed: make(chan struct{}),
	}
	provider.sessions[operationID] = session
	provider.activeByRoute[route.id] = operationID
	provider.mu.Unlock()
	go consumeAuthorizationEvents(processContext, provider.host, route, connection, processID, session)
	return session, nil
}

func consumeAuthorizationEvents(
	ctx context.Context,
	host managedCredentialAuthorizationHost,
	route *connectorRoute,
	connection agentruntime.ProcessConnection,
	processID uint64,
	session *credentialBrokerSession,
) {
	defer session.cancel()
	defer close(session.done)
	defer func() { _ = route.releaseProcess(processID, connection) }()
	var stdout, stderr strings.Builder
	for {
		frame, err := receiveCredentialBrokerFrameContext(ctx, connection)
		if err != nil {
			// Explicit cancellation owns the terminal state transition. Do not race
			// the caller by projecting a transient broker failure while shutdown is
			// already in progress.
			if errors.Is(ctx.Err(), context.Canceled) {
				return
			}
			if !errors.Is(err, io.EOF) {
				failAuthorizationSession(host, route, session, fmt.Errorf("receive connector credential broker event: %w", err))
			} else if !session.terminal() {
				failAuthorizationSession(host, route, session, errors.New("connector credential broker exited before a terminal event"))
			}
			return
		}
		stdout.Write(frame.Stdout)
		stderr.Write(frame.Stderr)
		if stdout.Len()+stderr.Len() > 1<<20 {
			failAuthorizationSession(host, route, session, errors.New("connector credential broker output exceeded its limit"))
			return
		}
		for {
			line, remaining, ok := strings.Cut(stdout.String(), "\n")
			if !ok {
				break
			}
			stdout.Reset()
			stdout.WriteString(remaining)
			if err := applyCredentialBrokerEvent(host, route, session, line); err != nil {
				failAuthorizationSession(host, route, session, err)
				return
			}
		}
		if frame.ExitCode != nil {
			if trailing := strings.TrimSpace(stdout.String()); trailing != "" {
				if err := applyCredentialBrokerEvent(host, route, session, trailing); err != nil {
					failAuthorizationSession(host, route, session, err)
					return
				}
			}
			if *frame.ExitCode != 0 && !session.terminal() {
				failAuthorizationSession(host, route, session, fmt.Errorf("connector credential broker exited with code %d: %s", *frame.ExitCode, boundedBrokerMessage(stderr.String())))
			} else if !session.terminal() {
				failAuthorizationSession(host, route, session, errors.New("connector credential broker exited before a terminal event"))
			}
			return
		}
	}
}

func applyCredentialBrokerEvent(host managedCredentialAuthorizationHost, route *connectorRoute, session *credentialBrokerSession, payload string) error {
	if strings.TrimSpace(payload) == "" {
		return nil
	}
	var event credentialBrokerEvent
	if err := decodeCredentialBrokerEvent(payload, &event); err != nil {
		return fmt.Errorf("decode connector credential broker event: %w", err)
	}
	switch event.Type {
	case "authorization_url":
		if !safeCredentialBrokerURL(event.URL, route.credentialBrokerLaunch.allowedHosts) {
			return errors.New("connector credential broker returned an unauthorized URL")
		}
		userCode, err := normalizeCredentialBrokerUserCode(event.Code)
		if err != nil {
			return err
		}
		session.update(market.AuthorizationStatePending, event.URL, userCode, nil)
		host.observeAuthorization(route, market.AuthorizationStatePending)
	case "connected":
		session.update(market.AuthorizationStateConnected, "", "", nil)
		host.observeAuthorization(route, market.AuthorizationStateConnected)
	case "error":
		return credentialBrokerEventError(event, "authorize")
	default:
		return fmt.Errorf("connector credential broker returned unsupported event type %q", event.Type)
	}
	return nil
}

func (host *Host) authorizationRoute(ctx context.Context, scope market.OperationScope, connector market.Connector) (*connectorRoute, error) {
	if host == nil {
		return nil, errors.New("managed connector authorization is unavailable")
	}
	releaseLane := host.enterConnectorLane(connector.Key)
	defer releaseLane()
	managed := connector.Release.Manifest.Implementation.ManagedStdio
	if connector.Release.Manifest.Implementation.Kind != market.ImplementationKindManagedStdio ||
		connector.Release.Manifest.AuthorizationKind == "none" || managed == nil || managed.CredentialBroker == nil ||
		!installationTargetsRelease(connector.Installation, connector.Release.ReleaseDigest) {
		return nil, errors.New("managed connector authorization is unavailable")
	}
	connectionID := "default"
	if accountID := strings.TrimSpace(scope.AccountID); accountID != "" {
		connectionID = market.AccountRuntimeConnectionID(accountID, connector.Key)
	}
	key := connectorRouteKey(connectionID, connector.Key)
	if route, _ := host.routes.Route(key).(*connectorRoute); route != nil && host.routeCurrent(route) && route.credentialBrokerLaunch != nil {
		return route, nil
	}
	host.authorizationMu.Lock()
	if route := host.authorizationRoutes[key]; route != nil && route.releaseDigest == connector.Release.ReleaseDigest &&
		route.credentialBrokerLaunch != nil && !route.processes.IsFenced() {
		host.authorizationMu.Unlock()
		return route, nil
	}
	host.authorizationMu.Unlock()
	route, err := host.buildAuthorizationRoute(ctx, connectionID, connector)
	if err != nil {
		return nil, err
	}
	host.authorizationMu.Lock()
	current := host.authorizationRoutes[key]
	if current == nil || current.releaseDigest != connector.Release.ReleaseDigest || current.processes.IsFenced() {
		host.authorizationRoutes[key] = route
		host.authorizationMu.Unlock()
		if current != nil {
			current.Fence()
			_ = current.Close(time.Now().Add(3 * time.Second))
		}
		return route, nil
	}
	host.authorizationMu.Unlock()
	route.Fence()
	_ = route.Close(time.Now().Add(3 * time.Second))
	return current, nil
}

func (host *Host) buildAuthorizationRoute(ctx context.Context, connectionID string, connector market.Connector) (*connectorRoute, error) {
	if err := market.ValidateRuntimeReleaseShape(connector.Release); err != nil {
		return nil, err
	}
	if !installationTargetsRelease(connector.Installation, connector.Release.ReleaseDigest) {
		return nil, errors.New("managed connector authorization release is not installed")
	}
	prepared, err := host.artifacts.ResolvePrepared(ctx, connector.Release)
	if err != nil {
		return nil, fmt.Errorf("resolve prepared connector artifact for authorization: %w", err)
	}
	installedRoot := prepared.PreparedPath
	executionRoot, err := host.snapshots.Create(prepared, artifactNativeEntrypoints(connector.Release)...)
	if err != nil {
		return nil, fmt.Errorf("create connector authorization snapshot: %w", err)
	}
	prepared.PreparedPath = executionRoot
	generation := connector.Revision
	if generation == 0 {
		generation = 1
	}
	runtimeRequest := market.RuntimeReconcileRequest{
		ConnectionID: connectionID,
		Connector:    connector,
		Generation:   market.HostGeneration{BootEpoch: "authorization", Generation: generation},
	}
	plan, err := host.planner.Build(ctx, runtimeRequest, prepared)
	if err != nil {
		_ = host.snapshots.Remove(executionRoot)
		return nil, err
	}
	route := newConnectorRoute(runtimeRequest)
	route.userHome = plan.UserHome
	route.executionRoot = executionRoot
	route.installedRoot = installedRoot
	route.snapshots = host.snapshots
	if plan.Managed.CLI == nil || plan.Managed.CredentialBroker == nil {
		_ = route.Close(time.Now().Add(3 * time.Second))
		return nil, errors.New("managed connector authorization requires a CLI credential broker")
	}
	if err := host.attachCLI(route, plan.Managed, prepared, plan.InstalledCLI, plan.Executable, plan.StateDir, plan.ArtifactTrees); err != nil {
		_ = route.Close(time.Now().Add(3 * time.Second))
		return nil, err
	}
	if err := host.attachCredentialBroker(route, plan.Managed.CredentialBroker, prepared, plan.Executable, plan.StateDir, plan.ArtifactTrees); err != nil {
		_ = route.Close(time.Now().Add(3 * time.Second))
		return nil, err
	}
	return route, nil
}

func (host *Host) observeAuthorization(route *connectorRoute, state market.AuthorizationState) {
	if host == nil || host.authorizationObserver == nil || route == nil {
		return
	}
	host.authorizationObserver.ObserveAuthorization(context.Background(), AuthorizationObservation{
		ConnectorKey: route.connectorKey, ConnectionID: route.connectionID, State: state, ObservedAt: time.Now().UTC(),
	})
}

func (host *Host) releaseAuthorizationRoute(route *connectorRoute) {
	if host == nil || route == nil {
		return
	}
	host.authorizationMu.Lock()
	if host.authorizationRoutes[route.id] == route {
		delete(host.authorizationRoutes, route.id)
	} else {
		host.authorizationMu.Unlock()
		return
	}
	host.authorizationMu.Unlock()
	route.Fence()
	_ = route.Close(time.Now().Add(3 * time.Second))
}

func (host *Host) releaseAuthorizationRouteByKey(key string) {
	if host == nil {
		return
	}
	host.authorizationMu.Lock()
	route := host.authorizationRoutes[key]
	delete(host.authorizationRoutes, key)
	host.authorizationMu.Unlock()
	if route != nil {
		route.Fence()
		_ = route.Close(time.Now().Add(3 * time.Second))
	}
}

func failAuthorizationSession(host managedCredentialAuthorizationHost, route *connectorRoute, session *credentialBrokerSession, err error) {
	session.fail(err)
	host.observeAuthorization(route, market.AuthorizationStateFailed)
}

func (host *Host) startCredentialBroker(
	ctx context.Context,
	route *connectorRoute,
	request credentialBrokerRequest,
) (agentruntime.ProcessConnection, uint64, error) {
	launch := route.credentialBrokerLaunch
	if launch == nil || request.Protocol != market.CredentialBrokerProtocolV1 ||
		(request.Operation != "begin" && request.Operation != "inspect" && request.Operation != "disconnect") {
		return nil, 0, errors.New("connector credential broker request is invalid")
	}
	spec := connectorruntime.ConnectorProcessSpec(route.connectionID, route.connectorKey, launch.language, launch.executable,
		launch.cwd, []string{launch.entrypoint}, launch.stateDir, route.userHome, launch.artifactTrees)
	cliLaunch, err := json.Marshal(launch.cliLaunch)
	if err != nil {
		return nil, 0, err
	}
	spec.Env = append(spec.Env,
		"TUTTI_CONNECTOR_CREDENTIAL_BROKER_PROTOCOL="+market.CredentialBrokerProtocolV1,
		"TUTTI_CONNECTOR_CLI_LAUNCH_JSON="+string(cliLaunch),
	)
	connection, processID, err := host.startProcess(ctx, route, spec, false)
	if err != nil {
		return nil, 0, err
	}
	payload, err := json.Marshal(request)
	if err == nil {
		err = connection.Send(append(payload, '\n'))
	}
	if err == nil {
		if graceful, ok := connection.(agentruntime.GracefulProcessConnection); ok {
			err = graceful.CloseInput()
		}
	}
	if err != nil {
		_ = route.releaseProcess(processID, connection)
		return nil, 0, err
	}
	return connection, processID, nil
}

func receiveCredentialBrokerFrameContext(ctx context.Context, connection agentruntime.ProcessConnection) (agentruntime.ProcessFrame, error) {
	if contextual, ok := connection.(agentruntime.ContextProcessConnection); ok {
		return contextual.RecvContext(ctx)
	}
	return connection.Recv()
}

func readCredentialBrokerTerminalEvent(ctx context.Context, connection agentruntime.ProcessConnection) (credentialBrokerEvent, error) {
	var output strings.Builder
	for {
		frame, err := receiveCredentialBrokerFrameContext(ctx, connection)
		if err != nil {
			return credentialBrokerEvent{}, err
		}
		output.Write(frame.Stdout)
		if output.Len() > 1<<20 {
			return credentialBrokerEvent{}, errors.New("connector credential broker output exceeded its limit")
		}
		for {
			line, remaining, ok := strings.Cut(output.String(), "\n")
			if !ok {
				break
			}
			output.Reset()
			output.WriteString(remaining)
			if strings.TrimSpace(line) == "" {
				continue
			}
			var event credentialBrokerEvent
			if err := decodeCredentialBrokerEvent(line, &event); err != nil {
				return credentialBrokerEvent{}, err
			}
			if event.Type == "disconnected" || event.Type == "error" {
				return event, nil
			}
			return credentialBrokerEvent{}, fmt.Errorf("unexpected credential broker disconnect event %q", event.Type)
		}
		if frame.ExitCode != nil {
			return credentialBrokerEvent{}, errors.New("connector credential broker exited before disconnect completed")
		}
	}
}

func readCredentialBrokerInspectionEvent(ctx context.Context, connection agentruntime.ProcessConnection) (credentialBrokerEvent, error) {
	var output strings.Builder
	for {
		frame, err := receiveCredentialBrokerFrameContext(ctx, connection)
		if err != nil {
			return credentialBrokerEvent{}, err
		}
		output.Write(frame.Stdout)
		if output.Len() > 1<<20 {
			return credentialBrokerEvent{}, errors.New("connector credential broker output exceeded its limit")
		}
		for {
			line, remaining, ok := strings.Cut(output.String(), "\n")
			if !ok {
				break
			}
			output.Reset()
			output.WriteString(remaining)
			if strings.TrimSpace(line) == "" {
				continue
			}
			var event credentialBrokerEvent
			if err := decodeCredentialBrokerEvent(line, &event); err != nil {
				return credentialBrokerEvent{}, err
			}
			switch event.Type {
			case "connected", "disconnected", "expired", "error":
				return event, nil
			default:
				return credentialBrokerEvent{}, fmt.Errorf("unexpected credential broker inspect event %q", event.Type)
			}
		}
		if frame.ExitCode != nil {
			return credentialBrokerEvent{}, errors.New("connector credential broker exited before inspect completed")
		}
	}
}

func decodeCredentialBrokerEvent(payload string, event *credentialBrokerEvent) error {
	decoder := json.NewDecoder(strings.NewReader(payload))
	decoder.DisallowUnknownFields()
	if err := decoder.Decode(event); err != nil {
		return err
	}
	if err := decoder.Decode(&struct{}{}); !errors.Is(err, io.EOF) {
		return errors.New("credential broker event contains trailing JSON")
	}
	return nil
}

func safeCredentialBrokerURL(value string, allowedHosts map[string]struct{}) bool {
	parsed, err := url.Parse(strings.TrimSpace(value))
	if err != nil || parsed.Scheme != "https" || parsed.User != nil || parsed.Hostname() == "" || parsed.Port() != "" {
		return false
	}
	_, allowed := allowedHosts[strings.ToLower(parsed.Hostname())]
	return allowed
}

func credentialBrokerEventError(event credentialBrokerEvent, operation string) error {
	message := boundedBrokerMessage(event.Message)
	if message == "" {
		message = "connector credential broker reported an error"
	}
	if code := strings.TrimSpace(event.Code); code != "" {
		return fmt.Errorf("%s connector authorization (%s): %s", operation, code, message)
	}
	return fmt.Errorf("%s connector authorization: %s", operation, message)
}

func boundedBrokerMessage(message string) string {
	message = strings.TrimSpace(message)
	if len(message) > 4096 {
		message = message[len(message)-4096:]
	}
	return message
}

func normalizeCredentialBrokerUserCode(value string) (string, error) {
	value = strings.TrimSpace(value)
	if utf8.RuneCountInString(value) > 128 {
		return "", errors.New("connector credential broker returned an oversized device code")
	}
	return value, nil
}

func (session *credentialBrokerSession) awaitEventAfter(ctx context.Context, afterStepRevision uint64) error {
	session.mu.Lock()
	hasEvent := session.hasEvent
	session.mu.Unlock()
	wait := credentialBrokerContinuationWait
	if !hasEvent {
		wait = credentialBrokerInitialEventTimeout
	}
	timer := time.NewTimer(wait)
	defer timer.Stop()
	for {
		session.mu.Lock()
		hasEvent = session.hasEvent
		version := session.version
		state := session.state
		changed := session.changed
		session.mu.Unlock()
		if hasEvent && (version > afterStepRevision || state == market.AuthorizationStateConnected || state == market.AuthorizationStateFailed) {
			return nil
		}
		select {
		case <-changed:
			continue
		case <-ctx.Done():
			return ctx.Err()
		case <-timer.C:
			session.mu.Lock()
			hasEvent = session.hasEvent
			session.mu.Unlock()
			if !hasEvent {
				return errors.New("connector credential broker did not return an initial event")
			}
			return nil
		}
	}
}

func (session *credentialBrokerSession) update(state market.AuthorizationState, authorizationURL, userCode string, err error) {
	session.mu.Lock()
	session.state = state
	session.url = authorizationURL
	session.userCode = userCode
	session.err = err
	session.version++
	session.hasEvent = true
	close(session.changed)
	session.changed = make(chan struct{})
	session.mu.Unlock()
}

func (session *credentialBrokerSession) fail(err error) {
	session.update(market.AuthorizationStateFailed, "", "", err)
}

func (session *credentialBrokerSession) snapshot() (market.AuthorizationState, string, string, uint64, error) {
	session.mu.Lock()
	defer session.mu.Unlock()
	return session.state, session.url, session.userCode, session.version, session.err
}

func (session *credentialBrokerSession) terminal() bool {
	session.mu.Lock()
	defer session.mu.Unlock()
	return session.state == market.AuthorizationStateConnected || session.err != nil
}

func (provider *managedCredentialAuthorizationProvider) takeAuthorizationSessionByRoute(routeID string) *credentialBrokerSession {
	provider.mu.Lock()
	defer provider.mu.Unlock()
	operationID := provider.activeByRoute[routeID]
	session := provider.sessions[operationID]
	delete(provider.activeByRoute, routeID)
	delete(provider.sessions, operationID)
	return session
}

func (provider *managedCredentialAuthorizationProvider) cancelAuthorizationSession(
	ctx context.Context,
	session *credentialBrokerSession,
) error {
	if provider == nil || session == nil {
		return nil
	}
	session.cancel()
	var closeErr error
	if session.connection != nil {
		closeErr = session.connection.Close()
	}
	select {
	case <-session.done:
		provider.clearAuthorizationSession(session.operationID, session)
		provider.host.releaseAuthorizationRoute(session.route)
		return closeErr
	case <-ctx.Done():
		return errors.Join(closeErr, fmt.Errorf("wait for connector credential broker termination: %w", ctx.Err()))
	}
}

func (provider *managedCredentialAuthorizationProvider) cancelAuthorizationSessionByRoute(routeID string) {
	if provider == nil {
		return
	}
	if session := provider.takeAuthorizationSessionByRoute(routeID); session != nil {
		session.cancel()
		if session.connection != nil {
			_ = session.connection.Close()
		}
	}
}

func (provider *managedCredentialAuthorizationProvider) clearAuthorizationSession(operationID string, session *credentialBrokerSession) {
	provider.mu.Lock()
	if provider.sessions[operationID] == session {
		delete(provider.sessions, operationID)
	}
	if session != nil && provider.activeByRoute[session.route.id] == operationID {
		delete(provider.activeByRoute, session.route.id)
	}
	provider.mu.Unlock()
}