import AssetGraph = require('assetgraph');
declare class UsageError extends Error {
    constructor(message: string);
}
/** Options for the subfont programmatic API. One of `output`, `inPlace`, or `dryRun` must be set. */
interface SubfontOptions {
    /** Path or URL to the web root. Deduced from `inputFiles` if omitted. */
    root?: string;
    /** URI root where the site will be deployed (rewrites absolute URLs). */
    canonicalRoot?: string;
    /** Output directory. Mutually exclusive with `inPlace`. */
    output?: string;
    /** Emit verbose timing and glyph-detection info. */
    debug?: boolean;
    /** Trace and compute subsets but do not write any files. */
    dryRun?: boolean;
    /** Suppress all log output. */
    silent?: boolean;
    /** Inline the subset @font-face CSS into the HTML document. */
    inlineCss?: boolean;
    /** CSS font-display value: `auto`, `block`, `swap`, `fallback`, or `optional`. */
    fontDisplay?: string;
    /** Modify input files in-place. */
    inPlace?: boolean;
    /** HTML entry points (file paths or URLs). */
    inputFiles?: Array<string | number | URL>;
    /** Crawl linked pages starting from `inputFiles`. */
    recursive?: boolean;
    /** Emit relative URLs instead of root-relative. */
    relativeUrls?: boolean;
    /** Trace JS-rendered content in headless Chrome. */
    dynamic?: boolean;
    /** Async-load the full original font as a fallback for dynamic content. */
    fallbacks?: boolean;
    /** Extra characters to include in every subset. */
    text?: string;
    /** Preserve CSS source maps (slower). */
    sourceMaps?: boolean;
    /**
     * Max parallel tracing workers. Defaults to CPU count, capped by available
     * memory. With `dynamic`, concurrent headless-Chrome tabs are always capped
     * at `MAX_POOL_SIZE` (8) regardless of this value.
     */
    concurrency?: number;
    /** Extra Chrome flags forwarded to puppeteer when `dynamic` is set. */
    chromeFlags?: string[];
    /** Cache subset results. Pass a path or `true` for `.subfont-cache` inside `root`. */
    cache?: boolean | string;
    /** Exit non-zero if any warnings are emitted. */
    strict?: boolean;
    /** Abort the run early. Cancels in-flight font tracing and subsetting. */
    signal?: AbortSignal;
}
interface SubfontFn {
    (options: SubfontOptions, console?: Console): Promise<InstanceType<typeof AssetGraph>>;
    UsageError: typeof UsageError;
}
declare const subfont: SubfontFn;
export = subfont;
//# sourceMappingURL=subfont.d.ts.map