import useSWRInifinite from "swr/infinite";
import type { Document } from "dbtype/api";
import { fetcher } from "./fetcher";
import useSWR from "swr";

interface SearchParams {
    word?: string;
    tags?: string;
    limit?: number;
    cursor?: number;
}

function makeSearchParams({
    word, tags, limit, cursor,
}: SearchParams){
    const search = new URLSearchParams();
    if (word) search.set("word", word);
    if (tags) search.set("allow_tag", tags);
    if (limit) search.set("limit", limit.toString());
    if (cursor) search.set("cursor", cursor.toString());
    return search;
}

export function useSearchGallery(searchParams: SearchParams = {}) {
    return useSWR<Document[]>(`/api/doc/search?${makeSearchParams(searchParams).toString()}`, fetcher);
}

export function useSearchGalleryInfinite(searchParams: SearchParams = {}) {
    return useSWRInifinite<
    {
        data: Document[];
        nextCursor: number | null;
        startCursor: number | null;
        hasMore: boolean;
    }
    >((index, previous) => {
        if (!previous && index > 0) return null;
        if (previous && !previous.hasMore) return null;
        const search = makeSearchParams(searchParams)
        if (index === 0) {
            return `/api/doc/search?${search.toString()}`;
        }
        if (!previous || !previous.data) return null;
        const last = previous.data[previous.data.length - 1];
        search.set("cursor", last.id.toString());
        return `/api/doc/search?${search.toString()}`;
    }, async (url) => {
        const limit = searchParams.limit;
        const res = await fetcher(url);
        return {
            data: res,
            startCursor: res.length === 0 ? null : res[0].id,
            nextCursor: res.length === 0 ? null : res[res.length - 1].id,
            hasMore: limit ? res.length === limit : (res.length === 20),
        };
    });
}