import { useEffect, useRef } from 'react';
import { useForge } from '../context/ForgeContext';

const FORGE_POLL_MS = 1000;

/** Poll GET /api/v1/builder/progress/{token} while a forge is running. */
export function useForgeProgressPoll(
  active: boolean,
  cancelTokenRef: React.RefObject<string>,
) {
  const { startForge, endForge, setStage } = useForge();
  const timerRef = useRef<ReturnType<typeof setTimeout> | null>(null);

  useEffect(() => {
    if (!active) {
      endForge();
      if (timerRef.current) clearTimeout(timerRef.current);
      return;
    }
    startForge();

    const token = cancelTokenRef.current;
    if (!token) return;

    let alive = true;

    const poll = async () => {
      if (!alive) return;
      try {
        const { authHeaders } = await import('../api/auth');
        const res = await fetch(`/api/v1/builder/progress/${encodeURIComponent(token)}`, {
          headers: authHeaders(),
        });
        if (res.ok) {
          const data: { stage?: string; pct?: number } = await res.json();
          const pct = typeof data.pct === 'number' ? data.pct : 0;
          if (alive && (data.stage || pct > 0)) {
            setStage(data.stage || 'Forging...', pct);
          }
        }
      } catch {
        // network hiccup — keep polling
      }
      if (alive) {
        timerRef.current = setTimeout(poll, FORGE_POLL_MS);
      }
    };

    poll();

    return () => {
      alive = false;
      if (timerRef.current) clearTimeout(timerRef.current);
    };
  // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [active]);
}