<?php

/**
 * Slim Framework (https://slimframework.com)
 *
 * @license https://github.com/slimphp/Slim/blob/4.x/LICENSE.md (MIT License)
 */

declare(strict_types=1);

namespace Slim\Tests\Mocks;

use Exception;
use InvalidArgumentException;
use Psr\Http\Message\StreamInterface;
use RuntimeException;

use function clearstatcache;
use function fclose;
use function feof;
use function fopen;
use function fread;
use function fseek;
use function fstat;
use function ftell;
use function fwrite;
use function gettype;
use function is_resource;
use function is_string;
use function stream_get_contents;
use function stream_get_meta_data;
use function var_export;

use const SEEK_SET;

class MockStream implements StreamInterface
{
    /** @var resource A resource reference */
    private $stream;

    /** @var bool */
    private $seekable;

    /** @var bool */
    private $readable;

    /** @var bool */
    private $writable;

    /** @var array|mixed|null|void */
    private $uri;

    /** @var int|null */
    private $size;

    /** @var array Hash of readable and writable stream types */
    private static $readWriteHash = [
        'read' => [
            'r' => true, 'w+' => true, 'r+' => true, 'x+' => true, 'c+' => true,
            'rb' => true, 'w+b' => true, 'r+b' => true, 'x+b' => true,
            'c+b' => true, 'rt' => true, 'w+t' => true, 'r+t' => true,
            'x+t' => true, 'c+t' => true, 'a+' => true,
        ],
        'write' => [
            'w' => true, 'w+' => true, 'rw' => true, 'r+' => true, 'x+' => true,
            'c+' => true, 'wb' => true, 'w+b' => true, 'r+b' => true,
            'x+b' => true, 'c+b' => true, 'w+t' => true, 'r+t' => true,
            'x+t' => true, 'c+t' => true, 'a' => true, 'a+' => true,
        ],
    ];

    /**
     * MockStream constructor.
     * @param string|resource $body
     */
    public function __construct($body = '')
    {
        if (is_string($body)) {
            $resource = fopen('php://temp', 'rw+');
            fwrite($resource, $body);
            $body = $resource;
        }

        if ('resource' === gettype($body)) {
            $this->stream = $body;
            $meta = stream_get_meta_data($this->stream);
            $this->seekable = $meta['seekable'];
            $this->readable = isset(self::$readWriteHash['read'][$meta['mode']]);
            $this->writable = isset(self::$readWriteHash['write'][$meta['mode']]);
            $this->uri = $this->getMetadata('uri');
        } else {
            throw new InvalidArgumentException(
                'First argument to Stream::create() must be a string, resource or StreamInterface.'
            );
        }
    }

    /**
     * Closes the stream when the destructed.
     */
    public function __destruct()
    {
        $this->close();
    }

    public function __toString(): string
    {
        try {
            if ($this->isSeekable()) {
                $this->seek(0);
            }

            return $this->getContents();
        } catch (Exception $e) {
            return '';
        }
    }

    public function close(): void
    {
        if (isset($this->stream)) {
            if (is_resource($this->stream)) {
                fclose($this->stream);
            }
            $this->detach();
        }
    }

    public function detach()
    {
        if (!isset($this->stream)) {
            return null;
        }

        $result = $this->stream;
        unset($this->stream);
        $this->size = $this->uri = null;
        $this->readable = $this->writable = $this->seekable = false;

        return $result;
    }

    public function getSize(): ?int
    {
        if (null !== $this->size) {
            return $this->size;
        }

        if (!isset($this->stream)) {
            return null;
        }

        // Clear the stat cache if the stream has a URI
        if ($this->uri) {
            clearstatcache(true, $this->uri);
        }

        $stats = fstat($this->stream);
        if (isset($stats['size'])) {
            $this->size = $stats['size'];

            return $this->size;
        }

        return null;
    }

    public function tell(): int
    {
        if (false === $result = ftell($this->stream)) {
            throw new RuntimeException('Unable to determine stream position');
        }

        return $result;
    }

    public function eof(): bool
    {
        return !$this->stream || feof($this->stream);
    }

    public function isSeekable(): bool
    {
        return $this->seekable;
    }

    public function seek($offset, $whence = SEEK_SET): void
    {
        if (!$this->seekable) {
            throw new RuntimeException('Stream is not seekable');
        }

        if (fseek($this->stream, $offset, $whence) === -1) {
            throw new RuntimeException(
                'Unable to seek to stream position '
                . $offset . ' with whence ' . var_export($whence, true)
            );
        }
    }

    public function rewind(): void
    {
        $this->seek(0);
    }

    public function isWritable(): bool
    {
        return $this->writable;
    }

    public function write($string): int
    {
        if (!$this->writable) {
            throw new RuntimeException('Cannot write to a non-writable stream');
        }

        // We can't know the size after writing anything
        $this->size = null;

        if (false === $result = fwrite($this->stream, $string)) {
            throw new RuntimeException('Unable to write to stream');
        }

        return $result;
    }

    public function isReadable(): bool
    {
        return $this->readable;
    }

    public function read($length): string
    {
        if (!$this->readable) {
            throw new RuntimeException('Cannot read from non-readable stream');
        }

        return fread($this->stream, $length);
    }

    public function getContents(): string
    {
        if (!isset($this->stream)) {
            throw new RuntimeException('Unable to read stream contents');
        }

        if (false === $contents = stream_get_contents($this->stream)) {
            throw new RuntimeException('Unable to read stream contents');
        }

        return $contents;
    }

    public function getMetadata($key = null)
    {
        if (!isset($this->stream)) {
            return $key ? null : [];
        }

        if (null === $key) {
            return stream_get_meta_data($this->stream);
        }

        $meta = stream_get_meta_data($this->stream);

        return $meta[$key] ?? null;
    }
}
