export interface MeterTier {
    id: string;
    at: number;
}
export type MeterMode = "hold" | "reset";
export interface AccumulatorMeterConfig {
    max: number;
    mode?: MeterMode;
    decayPerSecond?: number;
    decayDelayMs?: number;
    tiers?: readonly MeterTier[];
}
export interface MeterAddResult {
    value: number;
    fired: boolean;
    overflow: number;
    tier: string | null;
    tierChanged: boolean;
}
/** Mutable meter value, hold latch, and time since the last gain. */
export interface AccumulatorMeterState {
    value: number;
    broken: boolean;
    idleMs: number;
}
export interface AccumulatorMeter {
    /** Detached state for persistence and deterministic continuation. */
    state(): AccumulatorMeterState;
    /** Restore using the caller's existing configuration. */
    restore(next: AccumulatorMeterState): void;
    value(): number;
    fraction(): number;
    tier(): string | null;
    broke(): boolean;
    add(amount: number): MeterAddResult;
    drain(amount: number): void;
    reset(): void;
    tick(dtSeconds: number): void;
}
/** The highest tier id whose `at` threshold `value` has reached, or `null` below every tier — the pure lookup `createAccumulatorMeter`/`createEventMeter` call on every `add`/`tick`. */
export declare function tierAt(value: number, tiers: readonly MeterTier[]): string | null;
/**
 * A raw accumulating gauge that crosses named tier thresholds as a value builds, with optional decay — the primitive under charge, rage, and combo meters.
 *
 * @capability charge-meter fill a gauge toward named tier thresholds as a value accumulates
 */
export declare function createAccumulatorMeter(config: AccumulatorMeterConfig): AccumulatorMeter;