import { Context, Service } from 'koishi';
import { Config } from '..';
import { TempFileInfo, TempFileInfoWithData } from '../types';
export declare class ChatLunaStorageService extends Service {
    config: Config;
    private lruHead;
    private lruTail;
    private lruMap;
    private backendPath;
    private storageBackend;
    constructor(ctx: Context, config: Config);
    private getStorageConfig;
    private initStorageBackend;
    private initializeLRU;
    private addToLRU;
    private removeFromLRU;
    private getLRUVictim;
    private cleanupByStorageSize;
    private cleanupByFileCount;
    private downloadFile;
    private downloadFileStream;
    private removeFile;
    private deleteFileFromBackend;
    private setupAutoDelete;
    createTempFile(buffer: Buffer, filename: string, expireHours?: number, mimeType?: string): Promise<TempFileInfoWithData<Buffer>>;
    createTempFileFromStream(stream: NodeJS.ReadableStream, filename: string, meta?: {
        expireHours?: number;
        mimeType?: string;
        size?: number;
    }): Promise<TempFileInfoWithData<Buffer>>;
    getTempFile(id: string): Promise<TempFileInfoWithData<Buffer> | null>;
    /**
     * Get a temp file's metadata and a readable stream for its content.
     * Use this for serving files over HTTP to avoid loading entire files into memory.
     */
    getTempFileStream(id: string): Promise<(TempFileInfo & {
        stream: NodeJS.ReadableStream;
        url: string;
    }) | null>;
    deleteTempFile(id: string): Promise<boolean>;
}
declare module 'koishi' {
    interface Context {
        chatluna_storage: ChatLunaStorageService;
    }
    interface Tables {
        chatluna_storage_temp: TempFileInfo;
    }
}