<?php
namespace GuzzleHttp\Ring\Client;

use GuzzleHttp\Ring\Core;
use GuzzleHttp\Ring\Future\CompletedFutureArray;
use GuzzleHttp\Ring\Future\FutureArrayInterface;

/**
* Ring handler that returns a canned response or evaluated function result.
*/
class MockHandler
{
/** @var callable|array|FutureArrayInterface */
private $result;

/**
* Provide an array or future to always return the same value. Provide a
* callable that accepts a request object and returns an array or future
* to dynamically create a response.
*
* @param array|FutureArrayInterface|callable $result Mock return value.
*/
public function __construct($result)
{
$this->result = $result;
}

public function __invoke(array $request)
{
Core::doSleep($request);
$response = is_callable($this->result)
? call_user_func($this->result, $request)
: $this->result;

if (is_array($response)) {
$response = new CompletedFutureArray($response + [
'status' => null,
'body' => null,
'headers' => [],
'reason' => null,
'effective_url' => null,
]);
} elseif (!$response instanceof FutureArrayInterface) {
throw new \InvalidArgumentException(
'Response must be an array or FutureArrayInterface. Found '
. Core::describeType($request)
);
}

return $response;
}
}