/**
 * A tile source describes *where* to fetch raster XYZ tiles and what
 * attribution text the renderer must display in the chrome canvas.
 * Implementations are stateless — the tile loader handles caching and
 * in-flight dedup.
 */
export interface TileSource {
    /**
     * Build the URL for tile (z, x, y). Implementations typically
     * substitute a template like `{z}/{x}/{y}` and may rotate
     * subdomains for browsers that throttle concurrent connections
     * per host.
     */
    urlFor(z: number, x: number, y: number): string;
    /**
     * Plain-text attribution shown in the bottom-right of the chrome
     * canvas. Required by every major tile provider's terms of use —
     * do not suppress it without provider-side opt-out.
     */
    readonly attribution: string;
    /**
     * Side length of one tile in pixels. Tile providers ship 256 by
     * default; a few offer 512 (`@2x`) variants. Used by the zoom-
     * level picker to convert meters-per-pixel into a zoom level.
     */
    readonly tileSize: number;
    /**
     * Maximum zoom level the provider serves. Tiles requested above
     * this fall back to the deepest available level with sub-tile
     * UVs — same trick used during async loads.
     */
    readonly maxZoom: number;
    /**
     * Stable identifier for caching. Two `TileSource` instances with
     * the same `id` share a tile cache; switching source (e.g. theme
     * change) invalidates and re-fetches.
     */
    readonly id: string;
}
/**
 * Subdomain-rotated URL template. Replaces `{s}` with one of the
 * provided subdomains hashed by `(x + y)`, and `{z}`, `{x}`, `{y}`
 * with the tile address. Most major tile providers fit this shape.
 */
export declare class TemplatedTileSource implements TileSource {
    readonly id: string;
    private readonly template;
    readonly attribution: string;
    readonly tileSize: number;
    readonly maxZoom: number;
    private readonly subdomains;
    constructor(id: string, template: string, attribution: string, tileSize?: number, maxZoom?: number, subdomains?: readonly string[]);
    urlFor(z: number, x: number, y: number): string;
}
/**
 * Identifier of the default tile providers shipped with `viewer-charts`.
 * Surfaced as the `map_tile_provider` PluginConfig enum so users can
 * pick light vs. dark vs. labels-only without writing a custom source.
 */
export type TileProviderId = "carto-positron" | "carto-dark-matter" | "carto-voyager";
/**
 * Resolve a `TileProviderId` (from PluginConfig) to a concrete
 * `TileSource`. Unknown ids fall back to Positron so a misconfigured
 * `_pluginConfig` never produces a blank map.
 */
export declare function tileSourceFor(id: TileProviderId | string): TileSource;