import { ScaleSequential } from 'd3-scale';
import { ComputedRef, MaybeRefOrGetter } from '../../node_modules/vue';
/**
 * Reactive inputs driving {@link useChoropleth}. They mirror the
 * `ChoroplethMap` component's loaded data, the color-scale bounds and the
 * endpoint colors, accepted as plain values, refs or getters so the composable
 * adapts to how the caller wires its state.
 */
export interface UseChoroplethOptions {
    /**
     * The map's loaded data, keyed by feature identifier, as exposed by `useChart`.
     */
    loadedData: MaybeRefOrGetter<Record<string, number> | null>;
    /**
     * Path (dot notation supported) to a feature's identifier inside the geojson
     * datum, used to look its value up in `loadedData`.
     */
    topojsonObjectsPath: MaybeRefOrGetter<string | string[]>;
    /**
     * Forced maximum value for the color scale, or `null` to derive it from the data.
     */
    max: MaybeRefOrGetter<number | null>;
    /**
     * Forced minimum value for the color scale, or `null` to derive it from the data.
     */
    min: MaybeRefOrGetter<number | null>;
    /**
     * A custom scale function overriding the default sequential scale, or `null`
     * to use the default.
     */
    featureColorScale: MaybeRefOrGetter<((v: any) => string) | null>;
    /**
     * Color mapped to the scale's low end.
     */
    colorScaleStart: MaybeRefOrGetter<string>;
    /**
     * Color mapped to the scale's high end.
     */
    colorScaleEnd: MaybeRefOrGetter<string>;
}
/**
 * Reactive API returned by {@link useChoropleth}.
 */
export interface UseChoropleth {
    /**
     * The maximum value used by the color scale (forced or derived).
     */
    maxValue: ComputedRef<number>;
    /**
     * The minimum value used by the color scale (forced or derived).
     */
    minValue: ComputedRef<number>;
    /**
     * The default sequential scale, from the start color to the end color.
     */
    defaultFeatureColorScale: ComputedRef<ScaleSequential<string>>;
    /**
     * The active scale function: the custom one when provided, the default otherwise.
     */
    featureColorScaleFunction: ComputedRef<(v: any) => string>;
    /**
     * Maps a geojson datum to its color, or `null` when the feature has no data.
     */
    featureColor: ComputedRef<(d: any) => string | null>;
}
/**
 * Owns the pure color-scale logic of the `ChoroplethMap` component: it derives
 * the value bounds, builds the default sequential scale between the two
 * endpoint colors, and resolves a per-feature color from the loaded data. It
 * holds no DOM state — the endpoint colors are measured by the component and
 * passed in.
 *
 * @param options - Reactive color-scale options (see {@link UseChoroplethOptions}).
 * @returns The {@link UseChoropleth} API of derived color logic.
 * @example
 * // Internal building block of the `ChoroplethMap` component; not exported
 * // from the package root. Inside a `<script setup>` block:
 * import { toRef } from 'vue'
 * import { useChoropleth } from '@/composables/useChoropleth'
 *
 * const { featureColor, maxValue } = useChoropleth({
 *   loadedData,
 *   topojsonObjectsPath: toRef(() => props.topojsonObjectsPath),
 *   max: toRef(() => props.max),
 *   min: toRef(() => props.min),
 *   featureColorScale: toRef(() => props.featureColorScale),
 *   colorScaleStart: featureColorScaleStart,
 *   colorScaleEnd: featureColorScaleEnd
 * })
 */
export declare function useChoropleth(options: UseChoroplethOptions): UseChoropleth;
export default useChoropleth;