<?php
namespace Code_Snippets\Migration\Export;
use Code_Snippets\Model\Snippet;
use WP_Error;
use WP_Filesystem_Direct;
use ZipArchive;
use function sanitize_title;
use function wp_json_encode;
use function wp_delete_file;
use function wp_tempnam;
/**
* Builds downloadable snippet code files.
*
* @package Code_Snippets
*/
class Download_Code {
/**
* Bulk download archive filename.
*/
private const ARCHIVE_FILENAME_TEMPLATE = 'code-snippets-%d.zip';
/**
* Content types keyed by snippet type.
*
* @var array<string, string>
*/
private const CONTENT_TYPES = [
'php' => 'text/php',
'html' => 'text/html',
'css' => 'text/css',
'js' => 'text/javascript',
'cond' => 'application/json',
];
/**
* File extensions keyed by snippet type.
*
* @var array<string, string>
*/
private const FILE_EXTENSIONS = [
'php' => 'php',
'html' => 'html',
'css' => 'css',
'js' => 'js',
'cond' => 'json',
];
/**
* Build a single downloadable code file.
*
* @param Snippet $snippet Snippet to export.
*
* @return array{filename:string, content_type:string, content:string}
*/
public static function build_snippet_download( Snippet $snippet ): array {
$export = new Export_Code( [ $snippet->id ], $snippet->network );
return [
'filename' => self::build_filename( $snippet ),
'content_type' => self::CONTENT_TYPES[ $snippet->type ] ?? 'application/octet-stream',
'content' => self::build_content( $snippet, $export ),
];
}
/**
* Build a ZIP archive containing multiple snippet downloads.
*
* @param Snippet[] $snippets Snippets to export.
*
* @return array{filename:string, content_type:string, content:string}|WP_Error
*/
public static function build_archive_download( array $snippets ) {
$archive_filename = sprintf( self::ARCHIVE_FILENAME_TEMPLATE, time() );
if ( ! class_exists( ZipArchive::class ) ) {
return new WP_Error(
'zip_archive_unavailable',
__( 'Multiple snippet downloads require the ZipArchive PHP extension.', 'code-snippets' ),
[ 'status' => 501 ]
);
}
$temp_file = wp_tempnam( $archive_filename );
if ( ! is_string( $temp_file ) ) {
return new WP_Error(
'zip_archive_temp_file_failed',
__( 'The temporary download archive could not be created.', 'code-snippets' ),
[ 'status' => 500 ]
);
}
$zip = new ZipArchive();
$open_result = $zip->open( $temp_file, ZipArchive::CREATE | ZipArchive::OVERWRITE );
if ( true !== $open_result ) {
wp_delete_file( $temp_file );
return new WP_Error(
'zip_archive_open_failed',
__( 'The snippet download archive could not be created.', 'code-snippets' ),
[ 'status' => 500 ]
);
}
$used_filenames = [];
foreach ( $snippets as $snippet ) {
$download = self::build_snippet_download( $snippet );
$filename = self::get_unique_filename( $download['filename'], $snippet, $used_filenames );
$zip->addFromString( $filename, $download['content'] );
$used_filenames[ $filename ] = true;
}
$zip->close();
// WP_Filesystem_Direct is used intentionally here: the temp file was just created by
// wp_tempnam() on the local server filesystem, so the request filesystem context
// (FTP, SSH) is irrelevant. Using direct access avoids WP Filesystem bootstrapping
// overhead for a file we created and will immediately delete.
$filesystem = new WP_Filesystem_Direct( null );
$content = $filesystem->get_contents( $temp_file );
wp_delete_file( $temp_file );
if ( ! is_string( $content ) ) {
return new WP_Error(
'zip_archive_read_failed',
__( 'The snippet download archive could not be read.', 'code-snippets' ),
[ 'status' => 500 ]
);
}
return [
'filename' => $archive_filename,
'content_type' => 'application/zip',
'content' => $content,
];
}
/**
* Build the raw file content for a snippet download.
*
* @param Snippet $snippet Snippet being exported.
* @param Export_Code $export Export helper for PHP-aware formatting.
*
* @return string
*/
private static function build_content( Snippet $snippet, Export_Code $export ): string {
switch ( $snippet->type ) {
case 'html':
case 'css':
case 'js':
return self::normalize_content( $snippet->code );
case 'cond':
$decoded = json_decode( $snippet->code, true );
return JSON_ERROR_NONE === json_last_error()
? self::normalize_content( wp_json_encode( $decoded, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES ) )
: self::normalize_content( $snippet->code );
case 'php':
default:
return self::normalize_php_content( $export->generate_export() );
}
}
/**
* Build a deterministic filename for a snippet download.
*
* @param Snippet $snippet Snippet to export.
*
* @return string
*/
private static function build_filename( Snippet $snippet ): string {
$title = sanitize_title( $snippet->name );
if ( '' === $title ) {
$title = "snippet-$snippet->id";
}
$extension = self::FILE_EXTENSIONS[ $snippet->type ] ?? 'txt';
return "$title.code-snippets.$extension";
}
/**
* Normalize snippet content with a trailing newline.
*
* @param string $content Snippet content.
*
* @return string
*/
private static function normalize_content( string $content ): string {
$content = rtrim( $content );
return '' === $content ? '' : "$content\n";
}
/**
* Normalize PHP content to include an opening tag and trailing newline.
*
* @param string $content Snippet content.
*
* @return string
*/
private static function normalize_php_content( string $content ): string {
$content = ltrim( $content );
if ( 0 !== strpos( $content, '<?php' ) ) {
$content = "<?php\n\n" . ltrim( $content );
}
return self::normalize_content( $content );
}
/**
* Avoid duplicate filenames within the same archive.
*
* @param string $filename Proposed filename.
* @param Snippet $snippet Snippet being exported.
* @param array<string,bool> $used_filenames Archive filenames already in use.
*
* @return string
*/
private static function get_unique_filename( string $filename, Snippet $snippet, array $used_filenames ): string {
if ( ! isset( $used_filenames[ $filename ] ) ) {
return $filename;
}
$extension = self::FILE_EXTENSIONS[ $snippet->type ] ?? 'txt';
$title = sanitize_title( $snippet->name );
if ( '' === $title ) {
$title = 'snippet';
}
$counter = 2;
$unique_filename = sprintf( '%s-%d.code-snippets.%s', $title, $snippet->id, $extension );
while ( isset( $used_filenames[ $unique_filename ] ) ) {
$unique_filename = sprintf( '%s-%d-%d.code-snippets.%s', $title, $snippet->id, $counter, $extension );
++$counter;
}
return $unique_filename;
}
}