BookStack/app/Uploads/FaviconHandler.php
Dan Brown 2845e0003e
Got favicons better supported, can't get transparency right
Digging deeper, I don't think PHPGD supports 32bit bmp output which
complicates matters.
2023-02-09 15:14:41 +00:00

94 lines
3.0 KiB
PHP

<?php
namespace BookStack\Uploads;
use Illuminate\Http\UploadedFile;
use Intervention\Image\ImageManager;
class FaviconHandler
{
public function __construct(
protected ImageManager $imageTool
) {
}
/**
* Save the given UploadedFile instance as the application favicon.
*/
public function saveForUploadedImage(UploadedFile $file): void
{
$targetPath = public_path('favicon.ico');
if (!is_writeable($targetPath)) {
return;
}
$imageData = file_get_contents($file->getRealPath());
$image = $this->imageTool->make($imageData);
$image->resize(32, 32);
$bmpData = $image->encode('bmp');
$icoData = $this->bmpToIco($bmpData, 32, 32);
// file_put_contents(public_path('icon.bmp'), $bmpData);
// file_put_contents(public_path('icon-test.png'), $image->encode('png'));
file_put_contents($targetPath, $icoData);
}
/**
* Restore the original favicon image.
*/
public function restoreOriginal(): void
{
$targetPath = public_path('favicon.ico');
$original = public_path('icon.ico');
if (!is_writeable($targetPath)) {
return;
}
copy($original, $targetPath);
}
/**
* Convert BMP image data to ICO file format.
* Built following the file format info from Wikipedia:
* https://en.wikipedia.org/wiki/ICO_(file_format)
*/
protected function bmpToIco(string $bmpData, int $width, int $height): string
{
// Trim off the header of the bitmap file
$rawBmpData = substr($bmpData, 14);
// Double the height in the "BITMAPINFOHEADER" since, when in an ICO file, half
// of the image data is expected to be a mask.
$rawBmpData[8] = hex2bin(dechex($height * 2));
// ICO header
$header = pack('v', 0x00); // Reserved. Must always be 0
$header .= pack('v', 0x01); // Specifies ico image
$header .= pack('v', 0x01); // Specifies number of images
// ICO Image Directory
$entry = hex2bin(dechex($width)); // Image width
$entry .= hex2bin(dechex($height)); // Image height
$entry .= "\0"; // Color palette, typically 0
$entry .= "\0"; // Reserved
// AND mask
// $pxCount = $width * $height;
// $pxMask = hex2bin('00000000');
// $mask = str_repeat($pxMask, $pxCount);
$mask = '';
// Color planes, Appears to remain 1 for bmp image data
$entry .= pack('v', 0x01);
// Bits per pixel, can range from 1 to 32. From testing conversion
// via intervention from png typically provides this as 24.
$entry .= pack('v', 0x18);
// Size of the image data in bytes
$entry .= pack('V', strlen($rawBmpData) + strlen($mask));
// Offset of the bmp data from file start
$entry .= pack('V', strlen($header) + strlen($entry) + 4);
// Join & return the combined parts of the ICO image data
return $header . $entry . $rawBmpData . $mask;
}
}