import { ECharts, EChartsOption } from 'echarts';
/**
 * Render-time clamp that stops the first/last **category x-axis** labels from
 * clipping at the chart edges — *only when they actually overflow*.
 *
 * ECharts centers each category label on its tick; the first/last ticks sit at
 * the plot boundary, so a wide edge label spills past the chart and is cut off.
 * `grid.containLabel` does not contain this horizontal overflow and the v6
 * `outerBounds` shrink is unreliable, so we measure at render time and anchor
 * the overflowing edge label inward (`alignMinLabel: 'left'` /
 * `alignMaxLabel: 'right'`). Labels that fit stay centered.
 *
 * Lives in the generic bridge because the verdict needs the laid-out chart
 * (`convertToPixel`, `getWidth`); everything else is read from the `option`.
 * Auto-targets bar + histogram (category x-axis); pie's horizontal-bar fallback
 * (category *y*-axis), scatterplot (value) and timeseries (time) are skipped.
 */
export interface EdgeAlignment {
    alignMinLabel: 'left' | null;
    alignMaxLabel: 'right' | null;
}
export declare const CENTERED: EdgeAlignment;
/**
 * Pure overflow decision. Inputs are anchor-independent (tick centers and text
 * width don't depend on the label's current `text-anchor`), so feeding the
 * result back via `setOption` doesn't change them — the next pass yields the
 * same verdict, keeping the clamp loop-stable.
 */
export declare function decideEdgeAlignment(args: {
    firstLabel: string;
    lastLabel: string;
    font: string;
    firstTickX: number;
    lastTickX: number;
    width: number;
}): EdgeAlignment;
/**
 * Extracts the displayed first/last category strings and the label font from
 * the option, reading categories generically via `series[0].encode.x` into the
 * referenced dataset (`'name'` for bar, `0` for histogram). Returns `null` when
 * the option isn't a measurable category x-axis (fewer than 2 categories, no
 * dataset, etc.).
 */
export declare function resolveEdgeLabels(option: EChartsOption): {
    firstLabel: string;
    lastLabel: string;
    font: string;
    count: number;
} | null;
/**
 * Measures the rendered chart and, when the edge labels would clip, applies
 * `alignMinLabel`/`alignMaxLabel` (or clears them) via an imperative merge
 * `setOption`. Returns the alignment now in effect so the caller can keep a
 * `prev` ref and skip redundant `setOption`s. Should be invoked from the
 * chart's `finished` event (layout is settled, so `convertToPixel` is valid).
 */
export declare function clampEdgeLabels(chart: ECharts, option: EChartsOption, prev: EdgeAlignment): EdgeAlignment;