import type { APIAttachment, APIMessage, Awaitable } from 'discord.js';
/**
 * Subset of sharp's `WebpOptions`. `sharp` is an OPTIONAL peer dependency — it is
 * only needed for `.withCompression(..., convertToWebP)`. Typing it locally (instead
 * of `import('sharp')`) means consumers who don't use compression are not forced to
 * install sharp and don't get a "Cannot find module 'sharp'" error when type-checking.
 */
export interface WebpOptions {
    quality?: number;
    alphaQuality?: number;
    lossless?: boolean;
    nearLossless?: boolean;
    smartSubsample?: boolean;
    effort?: number;
    loop?: number;
    delay?: number | number[];
    minSize?: boolean;
    mixed?: boolean;
    force?: boolean;
    [option: string]: unknown;
}
/**
 * Callback used to save an image attachment.
 * The returned string is the URL that will be used in the transcript.
 *
 * `undefined` indicates to use the original attachment URL.
 * `null` indicates to not include the attachment in the transcript.
 * `string` indicates to use the returned URL as the attachment URL (base64 or remote image).
 */
export type ResolveImageCallback = (attachment: APIAttachment, message: APIMessage) => Awaitable<string | null | undefined>;
/**
 * Builder to build a image saving callback.
 */
export declare class TranscriptImageDownloader {
    private static log;
    private log;
    private maxFileSize?;
    private compression?;
    /**
     * Sets the maximum file size for *each* individual image.
     * @param size The maximum file size in kilobytes
     */
    withMaxSize(size: number): this;
    /**
     * Sets the maximum number of images downloaded concurrently.
     * @param n Concurrency (default 6)
     */
    withConcurrency(n: number): this;
    /**
     * Sets the compression quality for each image. This requires `sharp` to be installed.
     * Optionally, images can be converted to WebP format which is smaller in size.
     * @param quality The quality of the image (1 lowest - 100 highest). Lower quality means smaller file size.
     * @param convertToWebP Whether to convert the image to WebP format
     */
    withCompression(quality?: number, convertToWebP?: boolean, options?: Omit<WebpOptions, 'quality' | 'force'>): this;
    /**
     * Builds the image saving callback.
     */
    build(): ResolveImageCallback;
}