<?php
  
  /**
   * This file is part of the Carbon package.
   *
   * (c) Brian Nesbitt <brian@nesbot.com>
   *
   * For the full copyright and license information, please view the LICENSE
   * file that was distributed with this source code.
   */
  
  namespace Carbon\Traits;
  
  use Carbon\CarbonInterface;
  use Carbon\CarbonTimeZone;
  use Closure;
  use DateTimeImmutable;
  use DateTimeInterface;
  use InvalidArgumentException;
  use Throwable;
  
  trait Test
  {
      ///////////////////////////////////////////////////////////////////
      ///////////////////////// TESTING AIDS ////////////////////////////
      ///////////////////////////////////////////////////////////////////
  
      /**
       * A test Carbon instance to be returned when now instances are created.
       *
       * @var Closure|static|null
       */
      protected static $testNow;
  
      /**
       * The timezone to resto to when clearing the time mock.
       *
       * @var string|null
       */
      protected static $testDefaultTimezone;
  
      /**
       * Set a Carbon instance (real or mock) to be returned when a "now"
       * instance is created.  The provided instance will be returned
       * specifically under the following conditions:
       *   - A call to the static now() method, ex. Carbon::now()
       *   - When a null (or blank string) is passed to the constructor or parse(), ex. new Carbon(null)
       *   - When the string "now" is passed to the constructor or parse(), ex. new Carbon('now')
       *   - When a string containing the desired time is passed to Carbon::parse().
       *
       * Note the timezone parameter was left out of the examples above and
       * has no affect as the mock value will be returned regardless of its value.
       *
       * Only the moment is mocked with setTestNow(), the timezone will still be the one passed
       * as parameter of date_default_timezone_get() as a fallback (see setTestNowAndTimezone()).
       *
       * To clear the test instance call this method using the default
       * parameter of null.
       *
       * /!\ Use this method for unit tests only.
       *
       * @param DateTimeInterface|Closure|static|string|false|null $testNow real or mock Carbon instance
       */
      public static function setTestNow($testNow = null)
      {
          static::$testNow = $testNow instanceof self || $testNow instanceof Closure
              ? $testNow
              : static::make($testNow);
      }
  
      /**
       * Set a Carbon instance (real or mock) to be returned when a "now"
       * instance is created.  The provided instance will be returned
       * specifically under the following conditions:
       *   - A call to the static now() method, ex. Carbon::now()
       *   - When a null (or blank string) is passed to the constructor or parse(), ex. new Carbon(null)
       *   - When the string "now" is passed to the constructor or parse(), ex. new Carbon('now')
       *   - When a string containing the desired time is passed to Carbon::parse().
       *
       * It will also align default timezone (e.g. call date_default_timezone_set()) with
       * the second argument or if null, with the timezone of the given date object.
       *
       * To clear the test instance call this method using the default
       * parameter of null.
       *
       * /!\ Use this method for unit tests only.
       *
       * @param DateTimeInterface|Closure|static|string|false|null $testNow real or mock Carbon instance
       */
      public static function setTestNowAndTimezone($testNow = null, $tz = null)
      {
          if ($testNow) {
              self::$testDefaultTimezone = self::$testDefaultTimezone ?? date_default_timezone_get();
          }
  
          $useDateInstanceTimezone = $testNow instanceof DateTimeInterface;
  
          if ($useDateInstanceTimezone) {
              self::setDefaultTimezone($testNow->getTimezone()->getName(), $testNow);
          }
  
          static::setTestNow($testNow);
  
          if (!$useDateInstanceTimezone) {
              $now = static::getMockedTestNow(\func_num_args() === 1 ? null : $tz);
              $tzName = $now ? $now->tzName : null;
              self::setDefaultTimezone($tzName ?? self::$testDefaultTimezone ?? 'UTC', $now);
          }
  
          if (!$testNow) {
              self::$testDefaultTimezone = null;
          }
      }
  
      /**
       * Temporarily sets a static date to be used within the callback.
       * Using setTestNow to set the date, executing the callback, then
       * clearing the test instance.
       *
       * /!\ Use this method for unit tests only.
       *
       * @template T
       *
       * @param DateTimeInterface|Closure|static|string|false|null $testNow  real or mock Carbon instance
       * @param Closure(): T                                       $callback
       *
       * @return T
       */
      public static function withTestNow($testNow, $callback)
      {
          static::setTestNow($testNow);
  
          try {
              $result = $callback();
          } finally {
              static::setTestNow();
          }
  
          return $result;
      }
  
      /**
       * Get the Carbon instance (real or mock) to be returned when a "now"
       * instance is created.
       *
       * @return Closure|static the current instance used for testing
       */
      public static function getTestNow()
      {
          return static::$testNow;
      }
  
      /**
       * Determine if there is a valid test instance set. A valid test instance
       * is anything that is not null.
       *
       * @return bool true if there is a test instance, otherwise false
       */
      public static function hasTestNow()
      {
          return static::getTestNow() !== null;
      }
  
      /**
       * Get the mocked date passed in setTestNow() and if it's a Closure, execute it.
       *
       * @param string|\DateTimeZone $tz
       *
       * @return \Carbon\CarbonImmutable|\Carbon\Carbon|null
       */
      protected static function getMockedTestNow($tz)
      {
          $testNow = static::getTestNow();
  
          if ($testNow instanceof Closure) {
              $realNow = new DateTimeImmutable('now');
              $testNow = $testNow(static::parse(
                  $realNow->format('Y-m-d H:i:s.u'),
                  $tz ?: $realNow->getTimezone()
              ));
          }
          /* @var \Carbon\CarbonImmutable|\Carbon\Carbon|null $testNow */
  
          return $testNow instanceof CarbonInterface
              ? $testNow->avoidMutation()->tz($tz)
              : $testNow;
      }
  
      protected static function mockConstructorParameters(&$time, $tz)
      {
          /** @var \Carbon\CarbonImmutable|\Carbon\Carbon $testInstance */
          $testInstance = clone static::getMockedTestNow($tz);
  
          if (static::hasRelativeKeywords($time)) {
              $testInstance = $testInstance->modify($time);
          }
  
          $time = $testInstance instanceof self
              ? $testInstance->rawFormat(static::MOCK_DATETIME_FORMAT)
              : $testInstance->format(static::MOCK_DATETIME_FORMAT);
      }
  
      private static function setDefaultTimezone($timezone, DateTimeInterface $date = null)
      {
          $previous = null;
          $success = false;
  
          try {
              $success = date_default_timezone_set($timezone);
          } catch (Throwable $exception) {
              $previous = $exception;
          }
  
          if (!$success) {
              $suggestion = @CarbonTimeZone::create($timezone)->toRegionName($date);
  
              throw new InvalidArgumentException(
                  "Timezone ID '$timezone' is invalid".
                  ($suggestion && $suggestion !== $timezone ? ", did you mean '$suggestion'?" : '.')."
  ".
                  "It must be one of the IDs from DateTimeZone::listIdentifiers(),
  ".
                  'For the record, hours/minutes offset are relevant only for a particular moment, '.
                  'but not as a default timezone.',
                  0,
                  $previous
              );
          }
      }
  }