import { useState, useCallback } from "react";
import { API_URL } from "../config/authConstants";

const PAGE_SIZE = 20;

/**
 * Управляет основной лентой объявлений: загрузка, пагинация, поиск.
 */
export function useFeedPosts() {
  const [ads, setAds] = useState([]);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState("");
  const [page, setPage] = useState(0);
  const [hasMore, setHasMore] = useState(true);
  const [loadingMore, setLoadingMore] = useState(false);

  const loadFeed = useCallback(async (pageNum = 0, search = "", append = false) => {
    if (pageNum === 0) {
      setLoading(true);
    } else {
      setLoadingMore(true);
    }
    setError("");
    try {
      const params = new URLSearchParams({ page: pageNum, size: PAGE_SIZE });
      if (search) params.set("search", search);

      const res = await fetch(`${API_URL}/api/v1/posts?${params}`);
      if (!res.ok) throw new Error(`Error ${res.status}`);
      const data = await res.json();

      const content = data.content ?? [];
      const normalizedAds = content.map(ad => ({
        ...ad,
        type: ad.type ? ad.type.toLowerCase() : "loss",
      }));

      setAds(prev => (append ? [...prev, ...normalizedAds] : normalizedAds));
      setHasMore(!data.last);
      setPage(pageNum);
    } catch (err) {
      setError(err.message || "Failed to load ads");
    } finally {
      setLoading(false);
      setLoadingMore(false);
    }
  }, []);

  return { ads, loading, error, page, hasMore, loadingMore, loadFeed };
}