/**
 * Process state management for Godot MCP Enhanced.
 *
 * C-04: Async state-mutating operations are serialized through `enqueueAsync`.
 * Reads are still direct (no queueing) since they're atomic in the Node.js
 * single-threaded model. This prevents race conditions when MCP clients
 * introduce parallel tool calls.
 */
import type { ChildProcess } from 'child_process';
/** Kill process tree without blocking the event loop. Uses async spawn on Windows. */
export declare function forceKillTree(proc: ChildProcess): void;
/**
 * 按 PID 杀进程树（与 forceKillTree 共享双平台语义，IMPORTANT-1）。
 * Windows taskkill /F /T 清整树；POSIX pkill -P 杀子进程 + SIGTERM 主进程
 * （Godot 可能 spawn 导入/资源子进程，对等 forceKillTree POSIX 分支）。
 * 导出仅为测试可测性（@internal）。
 */
export declare function killPidTree(pid: number): void;
/** Async kill: waits for 'close' event, with 5 s fallback. */
export declare function killProcess(proc: ChildProcess): Promise<void>;
/** 记录本会话 spawn 的需要 orphan 兜底的 Godot 进程 PID（仅 run_project）。 */
export declare function registerSpawnedGodotPid(pid: number): void;
/** 进程正常退出时移除（主动清理，避免集合累积死 PID）。 */
export declare function unregisterSpawnedGodotPid(pid: number): void;
/** 测试用：读取当前集合。 */
export declare function getSpawnedGodotPids(): number[];
/** Serialize an async state-mutating operation. Ensures only one async mutation
 *  is in-flight at a time. Supports returning a value from the serialized function. */
declare function enqueueAsync<T>(fn: () => (Promise<T> | T)): Promise<T>;
export declare function isProcessBusy(): boolean;
/**
 * Acquire the long-running process slot through the async serialization queue.
 * Serialized via enqueueAsync to prevent race conditions when MCP clients
 * issue parallel tool calls (e.g. run_project + execute_gdscript simultaneously).
 * Returns true if acquired, false if slot is busy.
 */
export declare function acquireProcessSlot(owner?: string): Promise<boolean>;
export declare function setProcessBusy(busy: boolean): void;
/** Get info about what is currently holding the long-running lock. */
export declare function getBusyInfo(): {
    owner: string;
    startTime: number;
    projectDir: string;
};
/** Build a user-friendly error message when the long-running slot is occupied. */
export declare function buildBusyErrorMessage(): string;
export declare function acquireShortRunningSlot(): boolean;
export declare function releaseShortRunningSlot(): void;
export declare function getShortRunningCount(): number;
export declare function getRunningProcess(): ChildProcess | null;
export declare function setRunningProcess(proc: ChildProcess | null, skipBusyCheck?: boolean): void;
export declare function getOutputBuffer(): string[];
export declare function appendOutput(lines: string[]): void;
export declare function clearOutputBuffer(): void;
export declare function setOutputBuffer(buf: string[]): void;
export declare function getProcessStartTime(): number;
export declare function setProcessStartTime(t: number): void;
export declare function getProjectDir(): string;
export declare function setProjectDir(d: string): void;
/** Reset all module-level state — for test isolation. */
export declare function resetState(): void;
export { enqueueAsync };
export declare function killOrphanGodotProcesses(projectDir?: string, options?: {
    fullSystemScan?: boolean;
}): Promise<number>;