Spinner PHP Class With Seed

Example.php

<?php

$string = '{{The|A}} {{quick|speedy|fast}} {{brown|black|red}} {{fox|wolf}} {{jumped|bounded|hopped|skipped}} over the {{lazy|tired}} {{dog|hound}}';
 
echo '<p>';
 
for($i = 1; $i <= 5; $i++)
{
	echo Spinner::detect($string, false).'<br />';
    // or Spinner::flat($string, false).'<br />';
}
 
echo '</p>';

// nested
$string = '{{A {{simple|basic}} example|An uncomplicated scenario|The {{simplest|trivial|fundamental|rudimentary}} case|My {{test|invest{{igative|igation}}}} case}} to illustrate the {{function|problem}}';
 
echo '<p>';
 
for($i = 1; $i <= 5; $i++)
{
	echo Spinner::detect($string, false).'<br />';
	// or Spinner::nested($string, false).'<br />';
}
 
echo '</p>';

Spinner.php

<?php

class Spinner
{
	# Detects whether to use the nested or flat version of the spinner (costs some speed)
	public static function detect($text, $seedPageName = true, $openingConstruct = '{{', $closingConstruct = '}}', $separator = '|')
	{
		if(preg_match('~'.$openingConstruct.'(?:(?!'.$closingConstruct.').)*'.$openingConstruct.'~s', $text))
		{
			return self::nested($text, $seedPageName, $openingConstruct, $closingConstruct, $separator);
		}
		else
		{
			return self::flat($text, $seedPageName, false, $openingConstruct, $closingConstruct, $separator);
		}
	}
 
	# The flat version does not allow nested spin blocks, but is much faster (~2x)
	public static function flat($text, $seedPageName = true, $calculate = false, $openingConstruct = '{{', $closingConstruct = '}}', $separator = '|')
	{
		# Choose whether to return the string or the number of permutations
		$return = 'text';
		if($calculate)
		{
			$permutations	= 1;
			$return			= 'permutations';
		}
 
		# If we have nothing to spin just exit (don't use a regexp)
		if(strpos($text, $openingConstruct) === false)
		{
			return $$return;
		}
 
		if(preg_match_all('!'.$openingConstruct.'(.*?)'.$closingConstruct.'!s', $text, $matches))
		{
			# Optional, always show a particular combination on the page
			self::checkSeed($seedPageName);
 
			$find		= array();
			$replace	= array();
 
			foreach($matches[0] as $key => $match)
			{
				$choices = explode($separator, $matches[1][$key]);
 
				if($calculate)
				{
					$permutations *= count($choices);
				}
				else
				{
					$find[]		= $match;
					$replace[]	= $choices[mt_rand(0, count($choices) - 1)];
				}
			}
 
			if(!$calculate)
			{
				# Ensure multiple instances of the same spinning combinations will spin differently
				$text = self::str_replace_first($find, $replace, $text);
			}
		}
 
		return $$return;
	}
 
	# The nested version allows nested spin blocks, but is slower
	public static function nested($text, $seedPageName = true, $openingConstruct = '{{', $closingConstruct = '}}', $separator = '|')
	{
		# If we have nothing to spin just exit (don't use a regexp)
		if(strpos($text, $openingConstruct) === false)
		{
			return $text;
		}
 
		# Find the first whole match
		if(preg_match('!'.$openingConstruct.'(.+?)'.$closingConstruct.'!s', $text, $matches))
		{
			# Optional, always show a particular combination on the page
			self::checkSeed($seedPageName);
 
			# Only take the last block
			if(($pos = mb_strrpos($matches[1], $openingConstruct)) !== false)
			{
				$matches[1] = mb_substr($matches[1], $pos + mb_strlen($openingConstruct));
			}
 
			# And spin it
			$parts	= explode($separator, $matches[1]);
			$text	= self::str_replace_first($openingConstruct.$matches[1].$closingConstruct, $parts[mt_rand(0, count($parts) - 1)], $text);
 
			# We need to continue until there is nothing left to spin
			return self::nested($text, $seedPageName, $openingConstruct, $closingConstruct, $separator);
		}
		else
		{
			# If we have nothing to spin just exit
			return $text;
		}
	}
 
	# Similar to str_replace, but only replaces the first instance of the needle
	private static function str_replace_first($find, $replace, $string)
	{
		# Ensure we are dealing with arrays
		if(!is_array($find))
		{
			$find = array($find);
		}
 
		if(!is_array($replace))
		{
			$replace = array($replace);
		}
 
		foreach($find as $key => $value)
		{
			if(!empty($value))
			{
				if(($pos = mb_strpos($string, $value)) !== false)
				{
					# If we have no replacement make it empty
					if(!isset($replace[$key]))
					{
						$replace[$key] = '';
					}
 
					$string = mb_substr($string, 0, $pos).$replace[$key].mb_substr($string, $pos + mb_strlen($value));
				}
			}
		}
 
		return $string;
	}
 
	private static function checkSeed($seedPageName)
	{
		# Don't do the check if we are using random seeds
		if($seedPageName)
		{
			if($seedPageName === true)
			{
				mt_srand(crc32($_SERVER['REQUEST_URI']));
			}
			elseif($seedPageName == 'every second')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y-m-d-H-i-s')));
			}
			elseif($seedPageName == 'every minute')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y-m-d-H-i')));
			}
			elseif($seedPageName == 'hourly' OR $seedPageName == 'every hour')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y-m-d-H')));
			}
			elseif($seedPageName == 'daily' OR $seedPageName == 'every day')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y-m-d')));
			}
			elseif($seedPageName == 'weekly' OR $seedPageName == 'every week')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y-W')));
			}
			elseif($seedPageName == 'monthly' OR $seedPageName == 'every month')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y-m')));
			}
			elseif($seedPageName == 'annually' OR $seedPageName == 'every year')
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].date('Y')));
			}
			elseif(preg_match('!every ([0-9.]+) seconds!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / $matches[1])));
			}
			elseif(preg_match('!every ([0-9.]+) minutes!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / ($matches[1] * 60))));
			}
			elseif(preg_match('!every ([0-9.]+) hours!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / ($matches[1] * 3600))));
			}
			elseif(preg_match('!every ([0-9.]+) days!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / ($matches[1] * 86400))));
			}
			elseif(preg_match('!every ([0-9.]+) weeks!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / ($matches[1] * 604800))));
			}
			elseif(preg_match('!every ([0-9.]+) months!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / ($matches[1] * 2620800))));
			}
			elseif(preg_match('!every ([0-9.]+) years!', $seedPageName, $matches))
			{
				mt_srand(crc32($_SERVER['REQUEST_URI'].floor(time() / ($matches[1] * 31449600))));
			}
			else
			{
				throw new Exception($seedPageName. ' Was not a valid spin time option!');
			}
		}
	}
}