swoole-framwork/vendor/illuminate/support/Lottery.php
2024-05-20 11:51:07 +08:00

272 lines
5.7 KiB
PHP

<?php
namespace Illuminate\Support;
use RuntimeException;
class Lottery
{
/**
* The number of expected wins.
*
* @var int|float
*/
protected $chances;
/**
* The number of potential opportunities to win.
*
* @var int|null
*/
protected $outOf;
/**
* The winning callback.
*
* @var null|callable
*/
protected $winner;
/**
* The losing callback.
*
* @var null|callable
*/
protected $loser;
/**
* The factory that should be used to generate results.
*
* @var callable|null
*/
protected static $resultFactory;
/**
* Create a new Lottery instance.
*
* @param int|float $chances
* @param int|null $outOf
* @return void
*/
public function __construct($chances, $outOf = null)
{
if ($outOf === null && is_float($chances) && $chances > 1) {
throw new RuntimeException('Float must not be greater than 1.');
}
$this->chances = $chances;
$this->outOf = $outOf;
}
/**
* Create a new Lottery instance.
*
* @param int|float $chances
* @param int|null $outOf
* @return static
*/
public static function odds($chances, $outOf = null)
{
return new static($chances, $outOf);
}
/**
* Set the winner callback.
*
* @param callable $callback
* @return $this
*/
public function winner($callback)
{
$this->winner = $callback;
return $this;
}
/**
* Set the loser callback.
*
* @param callable $callback
* @return $this
*/
public function loser($callback)
{
$this->loser = $callback;
return $this;
}
/**
* Run the lottery.
*
* @param mixed ...$args
* @return mixed
*/
public function __invoke(...$args)
{
return $this->runCallback(...$args);
}
/**
* Run the lottery.
*
* @param null|int $times
* @return mixed
*/
public function choose($times = null)
{
if ($times === null) {
return $this->runCallback();
}
$results = [];
for ($i = 0; $i < $times; $i++) {
$results[] = $this->runCallback();
}
return $results;
}
/**
* Run the winner or loser callback, randomly.
*
* @param mixed ...$args
* @return callable
*/
protected function runCallback(...$args)
{
return $this->wins()
? ($this->winner ?? fn () => true)(...$args)
: ($this->loser ?? fn () => false)(...$args);
}
/**
* Determine if the lottery "wins" or "loses".
*
* @return bool
*/
protected function wins()
{
return static::resultFactory()($this->chances, $this->outOf);
}
/**
* The factory that determines the lottery result.
*
* @return callable
*/
protected static function resultFactory()
{
return static::$resultFactory ?? fn ($chances, $outOf) => $outOf === null
? random_int(0, PHP_INT_MAX) / PHP_INT_MAX <= $chances
: random_int(1, $outOf) <= $chances;
}
/**
* Force the lottery to always result in a win.
*
* @param callable|null $callback
* @return void
*/
public static function alwaysWin($callback = null)
{
self::setResultFactory(fn () => true);
if ($callback === null) {
return;
}
$callback();
static::determineResultNormally();
}
/**
* Force the lottery to always result in a lose.
*
* @param callable|null $callback
* @return void
*/
public static function alwaysLose($callback = null)
{
self::setResultFactory(fn () => false);
if ($callback === null) {
return;
}
$callback();
static::determineResultNormally();
}
/**
* Set the sequence that will be used to determine lottery results.
*
* @param array $sequence
* @param callable|null $whenMissing
* @return void
*/
public static function fix($sequence, $whenMissing = null)
{
return static::forceResultWithSequence($sequence, $whenMissing);
}
/**
* Set the sequence that will be used to determine lottery results.
*
* @param array $sequence
* @param callable|null $whenMissing
* @return void
*/
public static function forceResultWithSequence($sequence, $whenMissing = null)
{
$next = 0;
$whenMissing ??= function ($chances, $outOf) use (&$next) {
$factoryCache = static::$resultFactory;
static::$resultFactory = null;
$result = static::resultFactory()($chances, $outOf);
static::$resultFactory = $factoryCache;
$next++;
return $result;
};
static::setResultFactory(function ($chances, $outOf) use (&$next, $sequence, $whenMissing) {
if (array_key_exists($next, $sequence)) {
return $sequence[$next++];
}
return $whenMissing($chances, $outOf);
});
}
/**
* Indicate that the lottery results should be determined normally.
*
* @return void
*/
public static function determineResultNormally()
{
static::$resultFactory = null;
}
/**
* Set the factory that should be used to determine the lottery results.
*
* @param callable $factory
* @return void
*/
public static function setResultFactory($factory)
{
self::$resultFactory = $factory;
}
}