crawler

/**
 * searxng.ts — legacy-compatible search entry point backed by SearXNG.
 * Drop-in replacement for the old duckduckgo.ts search function.
 */

import { SearXNGProvider } from "./providers/SearXNGProvider";
import { SEARXNG_BASE_URL } from "../utils/constants";

// =============================================================
// 💾 IN-MEMORY CACHE (mirrors old duckduckgo.ts behaviour)
// =============================================================

interface CachedResult {
    value: Promise<string[]>;
    expiresAt: number;
}

const searchCache = new Map<string, CachedResult>();
const CACHE_TTL_MS = 30 * 60 * 1000; // 30 minutes

function getCachedResults(query: string): Promise<string[]> | null {
    const entry = searchCache.get(query);
    if (!entry) return null;
    if (Date.now() >= entry.expiresAt) {
        searchCache.delete(query);
        return null;
    }
    return entry.value;
}

function setCache(query: string, promise: Promise<string[]>): void {
    searchCache.set(query, { value: promise, expiresAt: Date.now() + CACHE_TTL_MS });
}

// =============================================================
// 🔎 CORE FUNCTION: searchSearXNG
// =============================================================

/**
 * Searches via a SearXNG instance.
 * @param query       The search term.
 * @param baseUrl     Override the SearXNG base URL (defaults to SEARXNG_BASE_URL constant).
 */
export async function searchSearXNG(
    query: string,
    baseUrl: string = SEARXNG_BASE_URL
): Promise<string[]> {
    const cached = getCachedResults(query);
    if (cached) {
        console.log(`\n============================================`);
        console.log(`[CACHE HIT] Returning cached results for: ${query}`);
        console.log(`============================================`);
        return cached;
    }

    console.log(`\n============================================`);
    console.log(`[INFO] Starting SearXNG search for "${query}" at ${baseUrl}`);
    console.log(`============================================`);

    try {
        const provider = new SearXNGProvider(baseUrl);
        const resultPromise = provider.search(query);

        setCache(query, resultPromise);

        const urls = await resultPromise;
        console.log(`[SUCCESS] Found ${urls.length} unique URLs.`);
        return urls;
    } catch (error) {
        const message = error instanceof Error ? error.message : "Unknown error";
        throw new Error(
            `[SEARCH FAILURE] SearXNG could not retrieve URLs for "${query}". Reason: ${message}`
        );
    }
}