<?php

declare(strict_types=1);

/**
 * 定时轮询拉取外部凭证并追加写入本地 txt（逻辑与 getcard 调同一 external 接口，仅触发节奏不同）。
 *
 * 设备：使用 config['poll'] 的机器 B 的 device_code / device_code_md5；getcard.php 使用顶层机器 A。
 * 原因：上游常对单设备或请求频次有限制，即时请求走 A、定时轮询走 B，避免抢同一套额度。
 *
 * 间隔：基准 5 分钟 ±3 分钟随机，且不少于 4 分钟（由「下次执行时间」控制）。
 * 宝塔 / Linux：计划任务每分钟执行一次本脚本；未到点会直接退出，不会请求外部接口。
 *
 * 示例 crontab（把路径改成你的站点根目录下的本文件）：
 *   * * * * * /usr/bin/php /www/wwwroot/你的域名/api/getcard_poll.php >>/www/wwwroot/你的域名/data/getcard_poll_cron.log 2>&1
 */

$cfg = require __DIR__ . '/../config.php';

$isCli = PHP_SAPI === 'cli';
$cronKey = isset($cfg['poll_cron_key']) ? (string)$cfg['poll_cron_key'] : '';
if (!$isCli) {
    if ($cronKey === '' || (($_GET['key'] ?? '') !== $cronKey)) {
        http_response_code(403);
        header('Content-Type: text/plain; charset=utf-8');
        echo 'Forbidden';
        exit;
    }
    header('Content-Type: text/plain; charset=utf-8');
}

$dataDir = __DIR__ . '/../data';
if (!is_dir($dataDir)) {
    if (!@mkdir($dataDir, 0755, true) && !is_dir($dataDir)) {
        sendcard_poll_out("Cannot create data directory: {$dataDir}\n");
        exit(1);
    }
}

$statePath = isset($cfg['poll_state_json']) && $cfg['poll_state_json'] !== ''
    ? (string)$cfg['poll_state_json']
    : $dataDir . DIRECTORY_SEPARATOR . 'getcard_poll_state.json';
$logPath = isset($cfg['poll_log_txt']) && $cfg['poll_log_txt'] !== ''
    ? (string)$cfg['poll_log_txt']
    : $dataDir . DIRECTORY_SEPARATOR . 'getcard_poll_log.txt';

$externalBase = trim((string)($cfg['external_base_url'] ?? ''));
if ($externalBase === '') {
    sendcard_poll_out("Config missing: external_base_url\n");
    exit(1);
}

try {
    $externalUrl = sendcard_poll_build_external_url($cfg);
} catch (InvalidArgumentException $e) {
    sendcard_poll_out('Config invalid: ' . $e->getMessage() . "\n");
    exit(1);
}

$now = time();
$fh = fopen($statePath, 'c+');
if ($fh === false) {
    sendcard_poll_out("Cannot open state file: {$statePath}\n");
    exit(1);
}

if (!flock($fh, LOCK_EX)) {
    fclose($fh);
    sendcard_poll_out("Cannot lock state file\n");
    exit(1);
}

$raw = stream_get_contents($fh);
$state = is_string($raw) && $raw !== '' ? json_decode($raw, true) : null;
if (!is_array($state)) {
    $state = [];
}
$nextRunAt = isset($state['next_run_at']) ? (int)$state['next_run_at'] : 0;

if ($now < $nextRunAt) {
    flock($fh, LOCK_UN);
    fclose($fh);
    $wait = $nextRunAt - $now;
    sendcard_poll_out("Skip: next run in {$wait}s (at " . date('Y-m-d H:i:s', $nextRunAt) . ")\n");
    exit(0);
}

require_once __DIR__ . '/../lib/external.php';

$linePrefix = '[' . date('Y-m-d H:i:s') . '] ';
$logBlock = '';

try {
    $resp = sendcard_fetch_credentials($externalUrl);
    $httpStatus = $resp['http_status'];
    $json = $resp['json'];
    $token = isset($json['data']['token']) ? (string)$json['data']['token'] : null;
    $logBlock = $token !== null && $token !== ''
        ? $token . "\n"
        : $linePrefix . "http={$httpStatus} token missing: " . json_encode($json, JSON_UNESCAPED_UNICODE) . "\n";
} catch (Throwable $e) {
    $logBlock = $linePrefix . 'ERROR ' . $e->getMessage() . "\n";
}

// $intervalSec = max(4 * 60, 5 * 60 + random_int(-3 * 60, 3 * 60));
$intervalSec = random_int(540, 840);
$newNext = $now + $intervalSec;
$state['next_run_at'] = $newNext;
$state['last_run_at'] = $now;
$state['last_interval_sec'] = $intervalSec;

rewind($fh);
ftruncate($fh, 0);
fwrite($fh, json_encode($state, JSON_UNESCAPED_UNICODE));
fflush($fh);
flock($fh, LOCK_UN);
fclose($fh);

if ($logBlock !== '') {
    file_put_contents($logPath, $logBlock, FILE_APPEND | LOCK_EX);
}

sendcard_poll_out(
    $logBlock . "Scheduled next run in {$intervalSec}s (at " . date('Y-m-d H:i:s', $newNext) . ")\n"
);
exit(0);

function sendcard_poll_out(string $msg): void
{
    echo $msg;
}

/**
 * 轮询请求 URL：使用 config['poll'] 下的 device_code、device_code_md5 作为查询参数值（与 getcard 顶层 device_* 分离）。
 *
 * @param array<string, mixed> $cfg
 */
function sendcard_poll_build_external_url(array $cfg): string
{
    $base = trim((string)($cfg['external_base_url'] ?? ''));
    if ($base === '') {
        throw new InvalidArgumentException('external_base_url');
    }

    $poll = $cfg['poll'] ?? null;
    if (!is_array($poll)) {
        throw new InvalidArgumentException("config['poll'] 须为数组且含 device_code、device_code_md5");
    }
    $dc = trim((string)($poll['device_code'] ?? ''));
    $dm = trim((string)($poll['device_code_md5'] ?? ''));
    if ($dc === '' || $dm === '') {
        throw new InvalidArgumentException("config['poll']['device_code'] 与 ['device_code_md5'] 勿留空");
    }

    return $base . '?device_code=' . rawurlencode($dc) . '&device_code_md5=' . rawurlencode($dm);
}