import type { ChildProcess } from 'node:child_process';
export type BrowserSessionEvent = 'startup' | 'semantic';
export type BrowserSessionExit = {
    code: number | null;
    signal: NodeJS.Signals | null;
};
export type BrowserSessionOutput = {
    chunk: string | Buffer;
    source: 'stderr' | 'stdout';
};
export type BrowserSessionTerminationReason = 'deadline' | 'parent-signal' | 'provider-watchdog' | 'semantic-stall' | 'startup-stall';
type BrowserSessionStream = {
    on(event: 'data', listener: (chunk: string | Buffer) => void): unknown;
    on(event: 'error', listener: (error: Error) => void): unknown;
};
export type BrowserSessionResult = {
    attempts: number;
    deadlineExceeded: boolean;
    diagnosticTail: string;
    exit: BrowserSessionExit;
    reason: 'exit' | BrowserSessionTerminationReason;
    startupProgress: boolean;
    semanticProgress: boolean;
};
export type BrowserSessionProcess = Pick<ChildProcess, 'kill'> & {
    processGroupId: number;
    on(event: 'close', listener: (code: number | null, signal: NodeJS.Signals | null) => void): unknown;
    on(event: 'error', listener: (error: Error) => void): unknown;
    on(event: 'exit', listener: (code: number | null, signal: NodeJS.Signals | null) => void): unknown;
    stderr?: BrowserSessionStream | null;
    stdout?: BrowserSessionStream | null;
};
export type BrowserSessionDeps = {
    clearInterval(handle: unknown): void;
    clearTimeout(handle: unknown): void;
    isProcessGroupAlive(processGroupId: number): boolean;
    killProcessGroup(processGroupId: number, signal: NodeJS.Signals): void;
    now(): number;
    offParentSignal(signal: NodeJS.Signals, listener: () => void): void;
    onParentSignal(signal: NodeJS.Signals, listener: () => void): void;
    setInterval(callback: () => void, ms: number): unknown;
    setTimeout(callback: () => void, ms: number): unknown;
    waitForProcessGroupExit(processGroupId: number, timeoutMs: number): Promise<void>;
};
export type BrowserSessionWatchdogController = {
    attempt: number;
    deadline: number;
    now(): number;
    process: BrowserSessionProcess;
    terminate(reason?: 'provider-watchdog'): void;
};
export type BrowserSessionWatchdogCleanup = () => void;
export type BrowserSessionWatchdog = (controller: BrowserSessionWatchdogController) => void | BrowserSessionWatchdogCleanup | Promise<void | BrowserSessionWatchdogCleanup>;
export type BrowserSessionOptions = {
    attempts: number;
    classifyExit(exit: BrowserSessionExit, result: Omit<BrowserSessionResult, 'attempts'>): 'retry' | 'return';
    deadlineMs: number;
    diagnosticTailBytes?: number;
    graceMs: number;
    onLine(line: string): BrowserSessionEvent | undefined;
    onOutput?(output: BrowserSessionOutput): void;
    onAttemptComplete?(result: BrowserSessionResult): void;
    processGroupDrainMs?: number;
    semanticStallMs: number;
    start(attempt: number): BrowserSessionProcess;
    startupStallMs: number;
    watchdogIntervalMs?: number;
    watchdog?: BrowserSessionWatchdog;
};
export {};