import 'dotenv/config';
import Database from 'better-sqlite3';

const db = new Database(process.env.DB_PATH || './data/db/oradio.sqlite');
const rows = db.prepare(`SELECT id, name, image_url FROM stations WHERE image_url IS NOT NULL AND image_url != ''`).all();

const TIMEOUT_MS = 8000;
const CONCURRENCY = 12;
const apply = process.argv.includes('--apply');

async function check(url) {
    const ctrl = new AbortController();
    const t = setTimeout(() => ctrl.abort(), TIMEOUT_MS);
    const headers = {
        'User-Agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/124.0 Safari/537.36',
        'Accept': 'image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8',
        'Accept-Language': 'en-US,en;q=0.9'
    };
    try {
        // Many CDNs don't support HEAD or return wrong content-type for HEAD; use a ranged GET.
        const res = await fetch(url, {
            method: 'GET',
            redirect: 'follow',
            signal: ctrl.signal,
            headers: { ...headers, Range: 'bytes=0-1023' }
        });
        if (!res.ok && res.status !== 206) {
            // Treat 4xx (except 429 rate-limit) as broken; 5xx as transient → keep.
            if (res.status === 429) return { ok: true, transient: true };
            if (res.status >= 500) return { ok: true, transient: true };
            return { ok: false, reason: `HTTP ${res.status}` };
        }
        const ct = (res.headers.get('content-type') || '').toLowerCase();
        if (ct && !ct.startsWith('image/') && !ct.includes('octet-stream')) {
            return { ok: false, reason: `bad content-type ${ct}` };
        }
        // Drain a small amount so the body is closed cleanly.
        try { await res.arrayBuffer(); } catch { }
        return { ok: true };
    } catch (err) {
        const code = err.cause?.code || err.code || err.name;
        // DNS / connection failures are definitive.
        if (['ENOTFOUND', 'EAI_AGAIN', 'ECONNREFUSED', 'ECONNRESET', 'EHOSTUNREACH', 'ETIMEDOUT'].includes(code)) {
            return { ok: false, reason: code };
        }
        if (err.name === 'AbortError') return { ok: true, transient: true }; // timeout, keep
        return { ok: false, reason: code || err.message };
    } finally {
        clearTimeout(t);
    }
}

const upd = db.prepare('UPDATE stations SET image_url = NULL WHERE id = ?');
let bad = 0, ok = 0;

async function worker(queue) {
    while (queue.length) {
        const r = queue.shift();
        const res = await check(r.image_url);
        if (res.ok) {
            ok++;
        } else {
            bad++;
            console.log(`BAD ${r.name} :: ${res.reason} :: ${r.image_url}`);
            if (apply) upd.run(r.id);
        }
    }
}

const queue = rows.slice();
console.log(`Checking ${queue.length} image_url values (apply=${apply})...`);
await Promise.all(Array.from({ length: CONCURRENCY }, () => worker(queue)));
console.log(`Done. ok=${ok} bad=${bad}${apply ? ' (cleared)' : ' (dry run; pass --apply to clear)'}`);