Smart convert images to webp

function convert_to_webp($file) {

    $file_path = $file['file'];

    $file_type = $file['type'];

    // Only for JPEG, PNG, and GIF images

    if (in_array($file_type, ['image/jpeg', 'image/png', 'image/gif', 'image/jpg'])) {

        $webp_path = preg_replace('/\.(jpe?g|png|gif)$/i', '.webp', $file_path);

        // Check if the GD library is available

        if (!function_exists('gd_info')) {

            error_log("GD library is not available.");

            return $file; // Return original file if GD is not available

        }

        // Convert image to WebP with default quality of 70%

        $default_quality = 70;

        $image = null;

        // Load the image based on its type

        switch ($file_type) {

            case 'image/jpeg':

            case 'image/jpg':

                $image = imagecreatefromjpeg($file_path);

                break;

            case 'image/png':

                $image = imagecreatefrompng($file_path);

                break;

            case 'image/gif':

                $image = imagecreatefromgif($file_path);

                break;

            default:

                error_log("Unsupported image type: $file_type");

                return $file; // Return original file if unsupported

        }

        // Check if the image was successfully loaded

        if ($image) {

            // Convert to WebP

            imagewebp($image, $webp_path, $default_quality);

            // Check the file size of the WebP file

            if (filesize($webp_path) > filesize($file_path)) {

                // Reduce quality until the size is smaller than the original file

                for ($quality = $default_quality - 10; $quality > 10; $quality -= 10) { // Avoid going below 10

                    imagewebp($image, $webp_path, $quality);

                    if (filesize($webp_path) < filesize($file_path)) {

                        break;

                    }

                }

            }

            // If the WebP file size is still larger, delete the WebP file

            if (filesize($webp_path) > filesize($file_path)) {

                unlink($webp_path);

            } else {

                // Delete the original file if it exists

                if (file_exists($file_path)) {

                    unlink($file_path);

                }

                $file['file'] = $webp_path;

                $file['type'] = 'image/webp';

            }

            // Free up resources

            imagedestroy($image);

        } else {

            // Log error if the image failed to load

            error_log("Failed to create image from: $file_path");

        }

    }

    return $file;

}

add_filter('wp_handle_upload', 'convert_to_webp');