<?php declare(strict_types=1);

namespace Lean\Response;

use function get_class, gettype, is_object, is_string, sprintfm, pathinfo, PATHINFO_EXTENSION;

use Psr\Http\Message\StreamInterface;

use Laminas\Diactoros\Exception,
    Laminas\Diactoros\Response,
    Laminas\Diactoros\Stream,
    Laminas\Diactoros\Response\InjectContentTypeTrait;

/**
 * PDF Response
 *
 * Allows creating a response by passing a string to the constructor;
 * by default, sets a status code of 200 and sets the Content-Type header to
 * application/pdf.
 */
class DownloadResponse extends Response
{
    use InjectContentTypeTrait;

    /**
     * Create a PDF response
     *
     * Produces a pdf response with a Content-Type of application/json and a default
     * status of 200.
     *
     * @param string|StreamInterface $content String or stream for the message body.
     * @param int $status Integer status code for the response; 200 by default.
     * @param array $headers Array of headers to use at initialization.
     * @throws Exception\InvalidArgumentException if $filepath is neither a string or stream.
     */
    public function __construct(string $content, string $filename, int $status = 200, array $headers = [])
    {
        parent::__construct(
            $this->createBody($content),
            $status,
            $this->injectFilename($filename, $this->injectContentType("application/octet-stream", $headers))
        );
    }    
    
    /**
     * Inject the provided Content-Type, if none is already present.
     *
     * @return array Headers with injected Content-Type
     */
    private function injectFilename(string $filename, array $headers) : array
    {
        $hasContentType = array_reduce(array_keys($headers), function ($carry, $item) {
            return $carry ?: (strtolower($item) === 'content-disposition');
        }, false);

        if (! $hasContentType) {
            $headers['content-disposition'] = ['Content-Disposition:attachment; filename="' . $filename . '"'];
        }

        return $headers;
    }

    /**
     * Create the message body.
     *
     * @param string|StreamInterface $content
     * @throws Exception\InvalidArgumentException if $content is neither a string or stream.
     */
    private function createBody(string $content) : StreamInterface
    {
        if ($content instanceof StreamInterface) {
            return $content;
        }

        $body = new Stream('php://temp', 'wb+');
        $body->write($content);
        $body->rewind();
        return $body;
    }
}