|
|
|
|
<?php
|
|
|
|
|
function room_qr_code_cached($room_id) {
|
|
|
|
|
global $QR_CODES;
|
|
|
|
|
return "$QR_CODES/$room_id.png";
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
|
* Use Google API to generate QR codes and encode them as base64
|
|
|
|
|
*/
|
|
|
|
|
function base64_qr_code($room_id, $join_url, $size = "512x512") {
|
|
|
|
|
// Could use http_build_query() instead, but I won't break what works.
|
|
|
|
|
// https://developers.google.com/chart/infographics/docs/qr_codes
|
|
|
|
|
$png_cached = room_qr_code_cached($room_id);
|
|
|
|
|
if (file_exists($png_cached))
|
|
|
|
|
// fwrite(STDERR, "QR code found for " . $room_id . PHP_EOL);
|
|
|
|
|
return base64_encode(file_get_contents($png_cached));
|
|
|
|
|
// fwrite(STDERR, "QR code NOT found for " . $room_id . PHP_EOL);
|
|
|
|
|
$data = urlencode($join_url);
|
|
|
|
|
$api_url =
|
|
|
|
|
"https://chart.googleapis.com/chart?cht=qr" .
|
|
|
|
|
"&chs=$size" .
|
|
|
|
|
"&chl=$data" .
|
|
|
|
|
"&chld=L|0";
|
|
|
|
|
// error correction level: L = 7%, M = 15%, Q = 25%, H = 30%
|
|
|
|
|
// | margin in number of rows
|
|
|
|
|
$png = file_get_contents($api_url);
|
|
|
|
|
file_put_contents($png_cached, $png);
|
|
|
|
|
return base64_encode($png);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
file_exists($QR_CODES) or mkdir($QR_CODES, 0700);
|
|
|
|
|
?>
|
|
|
|
|
|
|
|
|
|
<?php foreach ($rooms as $id => $room): ?>
|
|
|
|
|
<div id="modal_<?=$id?>" class="qr-code-modal">
|
|
|
|
|
<div class="qr-code-modal-content">
|
|
|
|
|
<span class="qr-code-modal-close" onclick='hideQRModal("<?=$id?>")'>
|
|
|
|
|
×
|
|
|
|
|
</span>
|
|
|
|
|
<img
|
|
|
|
|
src="data:image/png;base64,<?=base64_qr_code($id, $room->join_link)?>"
|
|
|
|
|
alt="Community join link encoded as QR code"
|
|
|
|
|
class="qr-code"
|
|
|
|
|
>
|
|
|
|
|
</div>
|
|
|
|
|
</div>
|
|
|
|
|
<?php endforeach; ?>
|
