import { AchievementTypes, ComboLamp, type Score, SyncLamp } from "../lib/types";
import type { Chart } from "gcm-database/maimai";
export declare function getMaxDxScore(chart: Chart): number;
/**
 * Get the amount of DX score stars given a DX score ratio.
 *
 * @param starRatio Ratio between achieved and maximum DX score, from 0 to 1.
 */
export declare function getDxStar(starRatio: number): 1 | 0 | 3 | 4 | -1 | 2 | 5;
/**
 * Amount of DX score stars of a score, or 0 when the chart has no notes.
 */
export declare function getDxStarOfScore(score: Score): 1 | 0 | 3 | 4 | -1 | 2 | 5;
/**
 * Compare two combo lamps. Negative when `a` is lower than `b`, positive when higher, 0 when equal.
 */
export declare function compareComboLamp(a: ComboLamp, b: ComboLamp): number;
/**
 * Compare two sync lamps. Negative when `a` is lower than `b`, positive when higher, 0 when equal.
 */
export declare function compareSyncLamp(a: SyncLamp, b: SyncLamp): number;
/**
 * Compare two achievement ranks. Negative when `a` is lower than `b`, positive when higher, 0 when equal.
 */
export declare function compareAchievementRank(a: AchievementTypes, b: AchievementTypes): number;