import { ResolvedChartSeries } from "../types";
import { ChartLayout } from "./getChartLayout";
import { LinePoint } from "./getLineSeries";
export type AreaPathSegment = {
    seriesLabel: string;
    color: string;
    d: string;
    /** 系列内の連続面。リサイズで d が変わっても key を安定させる */
    segmentIndex: number;
};
export type AreaChartLayout = "overlay" | "stacked";
/**
 * 幾何計算に含める系列。
 * - overlay: 全系列（非表示は DOM に残してフェードする）
 * - stacked: 表示中だけ（非表示を除いて積み直す）
 */
export declare function getAreaChartDrawSeries<T extends {
    label: string;
}>(series: readonly T[], hiddenLabels: ReadonlySet<string>, layout: AreaChartLayout): T[];
export declare function getOverlayAreaPath(points: readonly Pick<LinePoint, "x" | "y">[], baselineY: number): string;
export declare function getStackedAreaPath(upperPoints: readonly {
    x: number;
    y: number;
}[], lowerPoints: readonly {
    x: number;
    y: number;
}[]): string;
export declare function computeAreaChartMaxValue(series: readonly Pick<ResolvedChartSeries, "data">[], layout: AreaChartLayout, categoryCount?: number): number;
export declare function toStackedLineSeries(series: readonly ResolvedChartSeries[]): ResolvedChartSeries[];
export declare function getOverlayAreaSegments(item: ResolvedChartSeries, chartLayout: ChartLayout, maxValue: number): AreaPathSegment[];
export declare function getStackedAreaSegments(series: readonly ResolvedChartSeries[], chartLayout: ChartLayout, maxValue: number, categoryCount?: number): AreaPathSegment[];
export declare function getAreaSegments(series: readonly ResolvedChartSeries[], chartLayout: ChartLayout, maxValue: number, layout: AreaChartLayout, categoryCount?: number): AreaPathSegment[];