/**
 * Pure validation core of FileDropzone — typed rejections, accept matching
 * (MIME exact / wildcard / extension), size and collective count rules.
 * Ported behaviors from the react-dropzone reference study (blueprint M5).
 */
export type FileDropzoneErrorCode = "file-invalid-type" | "file-too-large" | "file-too-small" | "too-many-files";
export interface FileDropzoneError {
    /** One of the four built-in codes, or a custom code from `validator`. */
    code: FileDropzoneErrorCode | string;
    message: string;
}
export interface FileRejection {
    file: File;
    errors: FileDropzoneError[];
}
export interface ValidateFilesOptions {
    accept?: Record<string, string[]>;
    maxSize?: number;
    minSize?: number;
    maxFiles?: number;
    multiple?: boolean;
    validator?: (file: File) => FileDropzoneError | FileDropzoneError[] | null;
}
/**
 * Matches a file against an `accept` map ({mime: [ext...]}): exact MIME,
 * `type/*` wildcard, or extension (case-insensitive). No accept → accepts
 * everything. An empty `file.type` is accepted (Chrome reports "" for some
 * types during drag) — real validation happens again on drop.
 */
export declare function matchesAccept(file: File, accept?: Record<string, string[]>): boolean;
/**
 * Validates files against accept/size/count rules plus an optional custom
 * validator. Per-file errors accumulate; the maxFiles/multiple rule is
 * COLLECTIVE and all-or-nothing: exceeding it rejects EVERY file with
 * `too-many-files` (ported from the reference behavior).
 */
export declare function validateFiles(files: File[], options?: ValidateFilesOptions): {
    accepted: File[];
    rejections: FileRejection[];
};