stream.php

<?php
 
namespace Bitrix\Main\Web\Http;
 
use Psr\Http\Message\StreamInterface;
use Bitrix\Main\ArgumentException;
 
class Stream implements StreamInterface
{
    protected $resource;
 
    public function __construct($stream, $mode = 'r')
    {
        if (is_resource($stream))
        {
            $this->resource = $stream;
        }
        elseif ($stream instanceof Stream)
        {
            $this->resource = $stream->resource;
        }
        elseif (is_string($stream))
        {
            $this->resource = fopen($stream, $mode);
        }
        else
        {
            throw new ArgumentException('Stream must be a Stream object, a string identifier, or a resource.', 'stream');
        }
    }
 
    public function __toString(): string
    {
        if (!$this->isReadable())
        {
            return '';
        }
 
        try
        {
            $this->rewind();
            return $this->getContents();
        }
        catch (\RuntimeException)
        {
            return '';
        }
    }
 
    public function close(): void
    {
        if ($this->resource)
        {
            $resource = $this->detach();
            fclose($resource);
        }
    }
 
    public function detach()
    {
        $resource = $this->resource;
        $this->resource = null;
        return $resource;
    }
 
    public function getSize(): ?int
    {
        if ($this->resource !== null)
        {
            $stats = fstat($this->resource);
            return $stats['size'];
        }
        return null;
    }
 
    public function tell(): int
    {
        if (!$this->resource)
        {
            throw new \RuntimeException('No resource available, cannot tell position.');
        }
 
        $result = ftell($this->resource);
        if ($result === false)
        {
            throw new \RuntimeException('Error occurred during tell operation.');
        }
 
        return $result;
    }
 
    public function eof(): bool
    {
        if ($this->resource)
        {
            return feof($this->resource);
        }
        return true;
    }
 
    public function isSeekable(): bool
    {
        if ($this->resource)
        {
            return $this->getMetadata('seekable');
        }
 
        return false;
    }
 
    public function seek(int $offset, int $whence = SEEK_SET): void
    {
        if (!$this->resource)
        {
            throw new \RuntimeException('No resource available, cannot seek position.');
        }
 
        if (!$this->isSeekable())
        {
            throw new \RuntimeException('Stream is not seekable.');
        }
 
        $result = fseek($this->resource, $offset, $whence);
 
        if ($result !== 0)
        {
            throw new \RuntimeException('Error seeking within stream.');
        }
    }
 
    public function rewind(): void
    {
        $this->seek(0);
    }
 
    public function isWritable(): bool
    {
        if ($this->resource)
        {
            return is_writable($this->getMetadata('uri'));
        }
 
        return false;
    }
 
    public function write(string $string): int
    {
        if (!$this->resource)
        {
            throw new \RuntimeException('No resource available, cannot write.');
        }
 
        $result = fwrite($this->resource, $string);
 
        if ($result === false)
        {
            throw new \RuntimeException('Error writing to stream.');
        }
 
        return $result;
    }
 
    public function isReadable(): bool
    {
        if ($this->resource)
        {
            $mode = $this->getMetadata('mode');
 
            return (str_contains($mode, 'r') || str_contains($mode, '+'));
        }
 
        return false;
    }
 
    public function read(int $length): string
    {
        if (!$this->resource)
        {
            throw new \RuntimeException('No resource available, cannot read.');
        }
 
        if (!$this->isReadable())
        {
            throw new \RuntimeException('Stream is not readable.');
        }
 
        $result = fread($this->resource, $length);
 
        if ($result === false)
        {
            throw new \RuntimeException('Error reading stream.');
        }
 
        return $result;
    }
 
    public function getContents(): string
    {
        if (!$this->isReadable())
        {
            return '';
        }
 
        $result = stream_get_contents($this->resource);
 
        if ($result === false)
        {
            throw new \RuntimeException('Error reading stream.');
        }
 
        return $result;
    }
 
    public function getMetadata(?string $key = null)
    {
        $meta = stream_get_meta_data($this->resource);
 
        if ($key === null)
        {
            return $meta;
        }
 
        return $meta[$key] ?? null;
    }
 
    public function copyTo($stream)
    {
        $this->rewind();
        return stream_copy_to_stream($this->resource, $stream);
    }
}