import { Configuration } from '../models/public/configuration';
/**
 * Validates configuration and data before chart initialization.
 * Throws synchronously if DataItem.id is missing (V2 breaking change).
 *
 * @throws Error if any DataItem is missing the required `id` field.
 */
export declare function validateConfig(config: Configuration): boolean;
/**
 * Warns if data length exceeds 25 in auto/SVG mode (renderer was resolved at init).
 * Called during chart.update() when data crosses the 25-item boundary.
 * The renderer does NOT change — this is informational only.
 */
export declare function warnDataLimitExceeded(dataLength: number, resolvedRenderer: 'svg' | 'canvas'): void;
/**
 * Resolves the renderer type once at init time. Never changes after init.
 *
 * "auto" → SVG when data.length ≤ 25, Canvas otherwise.
 * Explicit "svg" or "canvas" → returns that directly.
 */
export declare function resolveRenderer(dataLength: number, mode: 'auto' | 'svg' | 'canvas'): 'svg' | 'canvas';