<?php
// yt_low_views.php
// Zoek YouTube-video's met weinig views en sorteer low->high

declare(strict_types=1);
ini_set('display_errors', '1');
error_reporting(E_ALL);

const API_BASE = 'https://www.googleapis.com/youtube/v3';
const API_KEY_FALLBACK = 'Hier moet je je API key van YT invullen'; // Mijn Youtube API Key

function api_key(): string {
 $k = getenv('YT_API_KEY');
 if (!$k || $k === '') $k = API_KEY_FALLBACK;
 if (!$k || $k === '') {
  http_response_code(500);
  exit('Fout: zet je API key in env YT_API_KEY of in API_KEY_FALLBACK');
 }
 return $k;
}

function http_get(string $path, array $params): array {
 $url = API_BASE.$path.'?'.http_build_query($params);
 $ch = curl_init($url);
 curl_setopt_array($ch, [
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_TIMEOUT => 15,
  CURLOPT_SSL_VERIFYPEER => true,
  CURLOPT_HTTPHEADER => ['Accept: application/json']
 ]);
 $res = curl_exec($ch);
 if ($res === false) {
  $err = curl_error($ch);
  curl_close($ch);
  exit('cURL error: '.$err);
 }
 $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
 curl_close($ch);
 if ($code < 200 || $code >= 300) exit('HTTP error '.$code.': '.$res);
 $data = json_decode($res, true);
 if (!is_array($data)) exit('JSON parse error');
 return $data;
}

function iso_utc(DateTime $dt): string {
 return $dt->setTimezone(new DateTimeZone('UTC'))->format('Y-m-d\TH:i:s\Z');
}

function days_since(string $iso): int {
 $dt = DateTime::createFromFormat('Y-m-d\TH:i:s\Z', $iso, new DateTimeZone('UTC'));
 if (!$dt) return 999999;
 $now = new DateTime('now', new DateTimeZone('UTC'));
 $days = (int) floor(($now->getTimestamp() - $dt->getTimestamp()) / 86400);
 return max(1, $days);
}

function fetch_video_stats(string $key, array $ids): array {
 if (!$ids) return [];
 $params = [
  'key' => $key,
  'part' => 'snippet,statistics',
  'id' => implode(',', $ids)
 ];
 $data = http_get('/videos', $params);
 $out = [];
 foreach (($data['items'] ?? []) as $it) {
  $sn = $it['snippet'] ?? [];
  $st = $it['statistics'] ?? [];
  $views = isset($st['viewCount']) ? (int)$st['viewCount'] : 0;
  $out[] = [
   'id' => (string)($it['id'] ?? ''),
   'title' => (string)($sn['title'] ?? ''),
   'channel' => (string)($sn['channelTitle'] ?? ''),
   'views' => $views,
   'publishedAt' => (string)($sn['publishedAt'] ?? '1970-01-01T00:00:00Z')
  ];
 }
 return $out;
}

function search_videos(string $key, string $query, int $pages, ?string $region, ?string $published_after, string $safe): array {
 $videos = [];
 $page_token = null;
 for ($i = 0; $i < $pages; $i++) {
  $params = [
   'key' => $key,
   'part' => 'snippet',
   'type' => 'video',
   'q' => $query,
   'maxResults' => 50,
   'safeSearch' => $safe
  ];
  if ($region) $params['regionCode'] = $region;
  if ($published_after) $params['publishedAfter'] = $published_after;
  if ($page_token) $params['pageToken'] = $page_token;
  $data = http_get('/search', $params);
  $ids = [];
  foreach (($data['items'] ?? []) as $it) {
   $id = $it['id']['videoId'] ?? null;
   if ($id) $ids[] = $id;
  }
  if ($ids) {
   $stats = fetch_video_stats($key, $ids);
   $videos = array_merge($videos, $stats);
  }
  $page_token = $data['nextPageToken'] ?? null;
  if (!$page_token) break;
  usleep(100000);
 }
 return $videos;
}

// ---------- UI + logica ----------
$q = trim($_GET['q'] ?? '');
$pages = max(1, (int)($_GET['pages'] ?? 2));
$max_views = isset($_GET['max_views']) && $_GET['max_views'] !== '' ? max(0, (int)$_GET['max_views']) : null;
$days = isset($_GET['days']) && $_GET['days'] !== '' ? max(1, (int)$_GET['days']) : null;
$region = $_GET['region'] ?? '';
$sort = in_array(($_GET['sort'] ?? 'views'), ['views','ratio'], true) ? $_GET['sort'] : 'views';
$limit = max(1, min(200, (int)($_GET['limit'] ?? 50)));
$safe = in_array(($_GET['safe'] ?? 'none'), ['none','moderate','strict'], true) ? $_GET['safe'] : 'none';

$videos = [];
if ($q !== '') {
 $key = api_key();
 $published_after = null;
 if ($days) {
  $since = new DateTime('now', new DateTimeZone('UTC'));
  $since->modify('-'.$days.' days');
  $published_after = iso_utc($since);
 }
 $videos = search_videos($key, $q, $pages, $region ?: null, $published_after, $safe);
 // filters
 $filtered = [];
 foreach ($videos as $v) {
  if ($max_views !== null && $v['views'] > $max_views) continue;
  if ($days !== null && days_since($v['publishedAt']) > $days) continue;
  $filtered[] = $v;
 }
 // sort
 if ($sort === 'views') {
  usort($filtered, function($a, $b) {
   return $a['views'] <=> $b['views'];
  });
 } else {
  usort($filtered, function($a, $b) {
   $ra = $a['views'] / days_since($a['publishedAt']);
   $rb = $b['views'] / days_since($b['publishedAt']);
   if ($ra == $rb) return 0;
   return ($ra < $rb) ? -1 : 1;
  });
 }
 $videos = array_slice($filtered, 0, $limit);
}

function h(string $s): string {
 return htmlspecialchars($s, ENT_QUOTES | ENT_SUBSTITUTE, 'UTF-8');
}
?>
<!doctype html>
<html lang="nl">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>YouTube low-views zoeker</title>
<style>
 body { font-family: system-ui, sans-serif; margin: 1rem; }
 form .row { display: grid; grid-template-columns: repeat(auto-fit,minmax(180px,1fr)); gap: .5rem; margin-bottom: .75rem; }
 input, select, button { padding: .4rem .5rem; }
 table { width: 100%; border-collapse: collapse; margin-top: .5rem; }
 th, td { padding: .4rem .5rem; border-bottom: 1px solid #ddd; vertical-align: top; }
 .views { text-align: right; white-space: nowrap; }
 .age { white-space: nowrap; }
 .meta { color: #444; font-size: .9em; }
</style>
</head>
<body>
<h1>YouTube low-views zoeker</h1>

<form method="get">
 <div class="row">
  <input type="text" name="q" placeholder="zoekterm (bv. arduino project)" value="<?=h($q)?>">
  <input type="number" name="pages" min="1" max="10" value="<?=h((string)$pages)?>" title="aantal search-pagina's (x50)">
  <input type="number" name="max_views" min="0" placeholder="max views (optioneel)" value="<?=h((string)($max_views ?? ''))?>">
  <input type="number" name="days" min="1" placeholder="max dagen oud (optioneel)" value="<?=h((string)($days ?? ''))?>">
  <input type="text" name="region" placeholder="regio (bv NL, US)" value="<?=h($region)?>">
  <select name="sort">
   <option value="views" <?= $sort==='views'?'selected':'' ?>>Sorteer: views (laag→hoog)</option>
   <option value="ratio" <?= $sort==='ratio'?'selected':'' ?>>Sorteer: views per dag</option>
  </select>
  <input type="number" name="limit" min="1" max="200" value="<?=h((string)$limit)?>">
  <select name="safe">
   <option value="none" <?= $safe==='none'?'selected':'' ?>>Safe: none</option>
   <option value="moderate" <?= $safe==='moderate'?'selected':'' ?>>Safe: moderate</option>
   <option value="strict" <?= $safe==='strict'?'selected':'' ?>>Safe: strict</option>
  </select>
 </div>
 <button type="submit">Zoek</button>
</form>

<?php if ($q !== ''): ?>
<p class="meta">Resultaten voor <b><?=h($q)?></b> (<?=count($videos)?> gevonden)</p>
<table>
 <thead>
  <tr>
   <th>#</th>
   <th>Video</th>
   <th class="views">Views</th>
   <th class="age">Leeftijd</th>
   <th>Channel</th>
  </tr>
 </thead>
 <tbody>
 <?php foreach ($videos as $i => $v): ?>
  <?php
   $age = days_since($v['publishedAt']);
   $url = 'https://www.youtube.com/watch?v='.urlencode($v['id']);
  ?>
  <tr>
   <td><?=($i+1)?></td>
   <td>
    <a href="<?=$url?>" target="_blank" rel="noopener"><?=h($v['title'])?></a><br>
    <span class="meta"><?=h($v['publishedAt'])?></span>
   </td>
   <td class="views"><?=number_format($v['views'], 0, ',', '.')?></td>
   <td class="age"><?=$age?> d</td>
   <td><?=h($v['channel'])?></td>
  </tr>
 <?php endforeach; ?>
 </tbody>
</table>
<?php endif; ?>

</body>
</html>