/**
 * InstanceRouter — request routing with switch lock (Phase 2b)
 *
 * Routes tool requests to the currently selected Godot instance.
 * Instance switching is atomic: in-flight requests complete before the switch.
 */
import type { InstanceInfo } from './instance-manager.js';
import type { ToolResult } from '../types.js';
export interface RouterDependencies {
    instances: InstanceInfo[];
    sendToInstance: (instance: InstanceInfo, toolName: string, args: Record<string, unknown>) => Promise<ToolResult>;
    onInstanceChanged?: (instance: InstanceInfo | null) => void;
}
export declare class InstanceRouter {
    private deps;
    /** H-01: O(1) lookup cache, rebuilt on updateInstances() */
    private instanceMap;
    private selectedId;
    private inflightCount;
    private inflightZeroResolve;
    /** I-11: Draining flag — blocks new route() calls while selectInstance waits for in-flight to drain. */
    private draining;
    constructor(deps: RouterDependencies);
    /** Rebuild the Map from the current instances array (copy-on-write). */
    private rebuildMap;
    /** Get currently selected instance id. */
    getSelectedId(): string | null;
    /** Get the currently selected InstanceInfo, or null. */
    getSelectedInstance(): InstanceInfo | null;
    /**
     * Auto-select instance based on count:
     * - 0 instances → null
     * - 1 instance → auto-select
     * - 2+ instances → null (requires explicit selection)
     */
    autoSelect(): string | null;
    /** Select instance by id. Throws if not found. */
    selectInstance(id: string): Promise<void>;
    /** Select instance by project path. Returns selected id or null.
     *  Only safe during initialization (no concurrent route() calls).
     *  Throws if draining is active (instance switch in progress). */
    selectInstanceByProject(projectPath: string): string | null;
    /** Route a tool request to the selected instance. Returns error string if no selection. */
    route(toolName: string, args: Record<string, unknown>): Promise<ToolResult | string>;
    /**
     * Resolve the best port for the selected instance using a priority chain:
     * 1. Original port still alive (same id + port in current instances)
     * 2. Same projectPath — pick most recent heartbeat
     * 3. Single instance available — use its port
     * 4. No match — null
     */
    resolvePort(): Promise<number | null>;
    /** Update the available instances list (e.g. after rediscovery). */
    updateInstances(instances: InstanceInfo[]): void;
}