// Bot tokenni o'rnating
define('BOT_TOKEN', '123456789:AAAAAAAA-BOT-TOKEN-HERE');
define('API_URL', 'https://api.telegram.org/bot' . BOT_TOKEN . '/');

function tgRequest($method, $params = [])
{
    $ch = curl_init();
    curl_setopt_array($ch, [
        CURLOPT_URL            => API_URL . $method,
        CURLOPT_POST           => true,
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_POSTFIELDS     => $params,
        CURLOPT_CONNECTTIMEOUT => 10,
        CURLOPT_TIMEOUT        => 30,
    ]);
    $res  = curl_exec($ch);
    $http = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $err  = curl_error($ch);
    curl_close($ch);

    if ($res === false  $http < 200  $http >= 300) {
        error_log("Telegram API error: HTTP $http; $err; response: $res");
        return false;
    }
    return json_decode($res, true);
}

/**
 * Yozmoqda/typing ko'rsatish
 * @param int|string $chat_id
 * @param string $action typing|upload_photo|record_video|upload_video|record_voice|upload_voice|upload_document|choose_sticker|find_location|record_video_note|upload_video_note
 * @param int $duration Sekundda qancha vaqt “yozmoqda” ko‘rsatilsin (0 bo‘lsa — bir marta yuboriladi)
 */
function sendChatAction($chat_id, $action = 'typing', $duration = 0)
{
    // Bir marta jo'natish
    if ($duration <= 0) {
        return tgRequest('sendChatAction', [
            'chat_id' => $chat_id,
            'action'  => $action
        ]);
    }

    // Uzoq jarayonlar uchun ma'lum oraliqda yangilab turish
    $end = time() + $duration;
    while (time() < $end) {
        tgRequest('sendChatAction', [
            'chat_id' => $chat_id,
            'action'  => $action
        ]);
        // Telegram typing ~5 sekundgacha ko'rinadi, 4 sekundda bir yangilaymiz
        sleep(4);
    }
    return true;
}

/** Oddiy xabar yuborish */
function sendMessage($chat_id, $text, $parse_mode = null)
{
    $params = ['chat_id' => $chat_id, 'text' => $text];
    if ($parse_mode) $params['parse_mode'] = $parse_mode;
    return tgRequest('sendMessage', $params);
}

/** Misol: uzoq jarayon oldidan “yozmoqda…” ko'rsatish */
function handleLongTask($chat_id)
{
    // 8 sekund davomida “yozmoqda…” ko‘rsatamiz
    sendChatAction($chat_id, 'typing', 8);

    // Bu yerda og‘ir hisob-kitob yoki API so‘rovlaringiz bo‘lishi mumkin
    // ...
    // Yakunda natijani yuboramiz
    sendMessage($chat_id, "Tayyor! Uzoq vazifa yakunlandi ✅");
}

// ---- Webhook/update namunasi ----
$update = json_decode(file_get_contents('php://input'), true);
if ($update && isset($update['message'])) {
    $chat_id = $update['message']['chat']['id'];
    $text    = trim($update['message']['text'] ?? '');

    if ($text === '/start') {
        // Qisqa typing
        sendChatAction($chat_id, 'typing');
        sendMessage($chat_id, "Assalomu alaykum! Men tayyorman.");
    } elseif ($text === '/heavy') {
        handleLongTask($chat_id);
    } else {
        sendChatAction($chat_id, 'typing');
        sendMessage($chat_id, "Buyruq: " . $text);
    }
}