import { shippingLanes } from "../data/shipping-lanes/shipping-lanes.js";
import { PortsLaneNotFoundError } from "../error-codes/error-codes.js";
import { recordLaneLookup } from "../otel/otel.js";
import type { LaneMode, ShippingLane } from "../types/port.types.js";

let laneIndex: Map<string, ShippingLane> | null = null;

function getIndex(): Map<string, ShippingLane> {
    if (laneIndex === null) {
        const map = new Map<string, ShippingLane>();
        for (const lane of shippingLanes) map.set(lane.id, lane);
        laneIndex = map;
    }
    return laneIndex;
}

/** Get a shipping lane by its ID, or `undefined` when no match exists. */
export function getShippingLane(id: string): ShippingLane | undefined {
    const lane = getIndex().get(id);
    recordLaneLookup(lane?.mode ?? "all");
    return lane;
}

/** Strict variant; throws `PortsLaneNotFoundError` (`PORTS.LANE_NOT_FOUND`) on miss. */
export function getShippingLaneStrict(id: string): ShippingLane {
    const lane = getShippingLane(id);
    if (lane === undefined) throw new PortsLaneNotFoundError({ laneId: id });
    return lane;
}

/** Filter shipping lanes by transport mode. */
export function getShippingLanesByMode(
    mode: LaneMode,
    lanes: readonly ShippingLane[] = shippingLanes
): ShippingLane[] {
    recordLaneLookup(mode);
    return lanes.filter((l) => l.mode === mode);
}

/** Get every shipping lane in the curated registry. */
export function getAllShippingLanes(): readonly ShippingLane[] {
    recordLaneLookup("all");
    return shippingLanes;
}