import { useState, useEffect } from 'react';
import type { WalkRoute } from '@timetoleave/core';
import { api } from '../services/api';

/**
 * Fetch walk route between two points using the OSRM walking router.
 * Skips the request if any coordinate is missing, resetting state to null.
 * Mirrors the web app's useWalkRoute hook.
 */
export function useWalkRoute(
  fromLat: number | undefined,
  fromLng: number | undefined,
  toLat: number | undefined,
  toLng: number | undefined,
) {
  const [walkRoute, setWalkRoute] = useState<WalkRoute | null>(null);
  const [loading, setLoading] = useState<boolean>(false);
  const [error, setError] = useState<string | null>(null);

  useEffect(() => {
    let isMounted = true;

    const fetchRoute = async () => {
      if (fromLat == null || fromLng == null || toLat == null || toLng == null) {
        setWalkRoute(null);
        setLoading(false);
        setError(null);
        return;
      }

      setLoading(true);
      setError(null);

      try {
        const data = await api.getWalkRoute(fromLat, fromLng, toLat, toLng);

        if (isMounted) {
          setWalkRoute(data);
          setLoading(false);
        }
      } catch (err: unknown) {
        if (isMounted) {
          const message = err instanceof Error ? err.message : 'Failed to fetch walk route';
          setError(message);
        }
      } finally {
        if (isMounted) {
          setLoading(false);
        }
      }
    };

    fetchRoute();

    return () => {
      isMounted = false;
    };
  }, [fromLat, fromLng, toLat, toLng]);

  return { walkRoute, loading, error };
}