import { useEffect, useState } from 'react';
import type { SubcableGeoJson, SubcableDetailsIndex, SubcableDetail } from '../model/types';

interface SubcableData {
  geo: SubcableGeoJson;
  details: Map<string, SubcableDetail>;
}

export function useSubcables(
  geoUrl = '/data/subcables/cable-geo.json',
  detailsUrl = '/data/subcables/cable-details.min.json',
) {
  const [data, setData] = useState<SubcableData | null>(null);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    let cancelled = false;

    async function run() {
      try {
        setError(null);
        const [geoRes, detailsRes] = await Promise.all([
          fetch(geoUrl),
          fetch(detailsUrl),
        ]);
        if (!geoRes.ok) throw new Error(`Failed to load subcable geo: ${geoRes.status}`);
        if (!detailsRes.ok) throw new Error(`Failed to load subcable details: ${detailsRes.status}`);

        const geo = (await geoRes.json()) as SubcableGeoJson;
        const detailsJson = (await detailsRes.json()) as SubcableDetailsIndex;
        if (cancelled) return;

        const details = new Map<string, SubcableDetail>();
        for (const [id, detail] of Object.entries(detailsJson.by_id)) {
          details.set(id, detail);
        }

        setData({ geo, details });
      } catch (e) {
        if (cancelled) return;
        setError(e instanceof Error ? e.message : String(e));
      }
    }

    void run();
    return () => {
      cancelled = true;
    };
  }, [geoUrl, detailsUrl]);

  return { data, error };
}