Random.php

<?php

namespace Drupal\Component\Utility;


/**
 * Defines a utility class for creating random data.
 *
 * @ingroup utility
 */
class Random {
    
    /**
     * The maximum number of times name() and string() can loop.
     *
     * This prevents infinite loops if the length of the random value is very
     * small.
     *
     * @see \Drupal\Tests\Component\Utility\RandomTest
     */
    const MAXIMUM_TRIES = 100;
    
    /**
     * A list of unique strings generated by string().
     *
     * @var array
     */
    protected $strings = [];
    
    /**
     * A list of unique names generated by name().
     *
     * @var array
     */
    protected $names = [];
    
    /**
     * A list of unique names generated by machineName().
     *
     * @var string[]
     */
    protected array $machineNames = [];
    
    /**
     * Generates a random string of ASCII characters of codes 32 to 126.
     *
     * The generated string includes alpha-numeric characters and common
     * miscellaneous characters. Use this method when testing general input
     * where the content is not restricted.
     *
     * @param int $length
     *   Length of random string to generate.
     * @param bool $unique
     *   (optional) If TRUE ensures that the random string returned is unique.
     *   Defaults to FALSE.
     * @param callable $validator
     *   (optional) A callable to validate the string. Defaults to NULL.
     *
     * @return string
     *   Randomly generated string.
     *
     * @see \Drupal\Component\Utility\Random::name()
     */
    public function string($length = 8, $unique = FALSE, $validator = NULL) {
        $counter = 0;
        // Continue to loop if $unique is TRUE and the generated string is not
        // unique or if $validator is a callable that returns FALSE. To generate a
        // random string this loop must be carried out at least once.
        do {
            if ($counter == static::MAXIMUM_TRIES) {
                throw new \RuntimeException('Unable to generate a unique random name');
            }
            $str = '';
            for ($i = 0; $i < $length; $i++) {
                $str .= chr(mt_rand(32, 126));
            }
            $counter++;
            $continue = FALSE;
            if ($unique) {
                $continue = isset($this->strings[$str]);
            }
            if (!$continue && is_callable($validator)) {
                // If the validator callback returns FALSE generate another random
                // string.
                $continue = !call_user_func($validator, $str);
            }
        } while ($continue);
        if ($unique) {
            $this->strings[$str] = TRUE;
        }
        return $str;
    }
    
    /**
     * Generates a random string containing letters and numbers.
     *
     * The string will always start with a letter. The letters may be upper or
     * lower case. This method is better for restricted inputs that do not
     * accept certain characters. For example, when testing input fields that
     * require machine readable values (i.e. without spaces and non-standard
     * characters) this method is best.
     *
     * @param int $length
     *   Length of random string to generate.
     * @param bool $unique
     *   (optional) If TRUE ensures that the random string returned is unique.
     *   Defaults to FALSE.
     *
     * @return string
     *   Randomly generated string.
     *
     * @see \Drupal\Component\Utility\Random::string()
     */
    public function name($length = 8, $unique = FALSE) {
        $values = array_merge(range(65, 90), range(97, 122), range(48, 57));
        $max = count($values) - 1;
        $counter = 0;
        do {
            if ($counter == static::MAXIMUM_TRIES) {
                throw new \RuntimeException('Unable to generate a unique random name');
            }
            $str = chr(mt_rand(97, 122));
            for ($i = 1; $i < $length; $i++) {
                $str .= chr($values[mt_rand(0, $max)]);
            }
            $counter++;
        } while ($unique && isset($this->names[$str]));
        if ($unique) {
            $this->names[$str] = TRUE;
        }
        return $str;
    }
    
    /**
     * Generates a string containing lowercase letters and numbers.
     *
     * This method is used to generate strings that are compliant with Drupal
     * machine names. This doesn't include underscores, dashes and periods since
     * those are not compatible with all machine names.
     *
     * @param int $length
     *   Length of random string to generate.
     * @param bool $unique
     *   If TRUE ensures that the random string returned is unique.
     *   Defaults to FALSE.
     *
     * @return string
     *   Randomly generated string.
     *
     * @throws \RuntimeException
     *   Thrown if a unique machine name cannot be generated within the allowed
     *   number of random attempts.
     *
     * @see \Drupal\Component\Utility\Random::string()
     */
    public function machineName(int $length = 8, bool $unique = FALSE) : string {
        $values = array_merge(range('a', 'z'), range(0, 9));
        $start_characters = range('a', 'z');
        $counter = 0;
        do {
            if ($counter == static::MAXIMUM_TRIES) {
                throw new \RuntimeException('Unable to generate a unique random machine name');
            }
            $str = $start_characters[array_rand($start_characters)];
            for ($i = 1; $i < $length; $i++) {
                $str .= $values[array_rand($values)];
            }
            $counter++;
        } while ($unique && isset($this->machineNames[$str]));
        if ($unique) {
            $this->machineNames[$str] = TRUE;
        }
        return $str;
    }
    
    /**
     * Generate a string that looks like a word (letters only, alternating consonants and vowels).
     *
     * @param int $length
     *   The desired word length.
     *
     * @return string
     */
    public function word($length) {
        $vowels = [
            "a",
            "e",
            "i",
            "o",
            "u",
        ];
        $cons = [
            "b",
            "c",
            "d",
            "g",
            "h",
            "j",
            "k",
            "l",
            "m",
            "n",
            "p",
            "r",
            "s",
            "t",
            "u",
            "v",
            "w",
            "tr",
            "cr",
            "br",
            "fr",
            "th",
            "dr",
            "ch",
            "ph",
            "wr",
            "st",
            "sp",
            "sw",
            "pr",
            "sl",
            "cl",
            "sh",
        ];
        $num_vowels = count($vowels);
        $num_cons = count($cons);
        $word = '';
        while (strlen($word) < $length) {
            $word .= $cons[mt_rand(0, $num_cons - 1)] . $vowels[mt_rand(0, $num_vowels - 1)];
        }
        return substr($word, 0, $length);
    }
    
    /**
     * Generates a random PHP object.
     *
     * @param int $size
     *   The number of random keys to add to the object.
     *
     * @return object
     *   The generated object, with the specified number of random keys. Each key
     *   has a random string value.
     */
    public function object($size = 4) {
        $object = new \stdClass();
        for ($i = 0; $i < $size; $i++) {
            $random_key = $this->name();
            $random_value = $this->string();
            $object->{$random_key} = $random_value;
        }
        return $object;
    }
    
    /**
     * Generates sentences Latin words, often used as placeholder text.
     *
     * @param int $min_word_count
     *   The minimum number of words in the return string. Total word count
     *   can slightly exceed provided this value in order to deliver
     *   sentences of random length.
     * @param bool $capitalize
     *   Uppercase all the words in the string.
     *
     * @return string
     *   Nonsense latin words which form sentence(s).
     */
    public function sentences($min_word_count, $capitalize = FALSE) {
        // cSpell:disable
        $dictionary = [
            "abbas",
            "abdo",
            "abico",
            "abigo",
            "abluo",
            "accumsan",
            "acsi",
            "ad",
            "adipiscing",
            "aliquam",
            "aliquip",
            "amet",
            "antehabeo",
            "appellatio",
            "aptent",
            "at",
            "augue",
            "autem",
            "bene",
            "blandit",
            "brevitas",
            "caecus",
            "camur",
            "capto",
            "causa",
            "cogo",
            "comis",
            "commodo",
            "commoveo",
            "consectetuer",
            "consequat",
            "conventio",
            "cui",
            "damnum",
            "decet",
            "defui",
            "diam",
            "dignissim",
            "distineo",
            "dolor",
            "dolore",
            "dolus",
            "duis",
            "ea",
            "eligo",
            "elit",
            "enim",
            "erat",
            "eros",
            "esca",
            "esse",
            "et",
            "eu",
            "euismod",
            "eum",
            "ex",
            "exerci",
            "exputo",
            "facilisi",
            "facilisis",
            "fere",
            "feugiat",
            "gemino",
            "genitus",
            "gilvus",
            "gravis",
            "haero",
            "hendrerit",
            "hos",
            "huic",
            "humo",
            "iaceo",
            "ibidem",
            "ideo",
            "ille",
            "illum",
            "immitto",
            "importunus",
            "imputo",
            "in",
            "incassum",
            "inhibeo",
            "interdico",
            "iriure",
            "iusto",
            "iustum",
            "jugis",
            "jumentum",
            "jus",
            "laoreet",
            "lenis",
            "letalis",
            "lobortis",
            "loquor",
            "lucidus",
            "luctus",
            "ludus",
            "luptatum",
            "macto",
            "magna",
            "mauris",
            "melior",
            "metuo",
            "meus",
            "minim",
            "modo",
            "molior",
            "mos",
            "natu",
            "neo",
            "neque",
            "nibh",
            "nimis",
            "nisl",
            "nobis",
            "nostrud",
            "nulla",
            "nunc",
            "nutus",
            "obruo",
            "occuro",
            "odio",
            "olim",
            "oppeto",
            "os",
            "pagus",
            "pala",
            "paratus",
            "patria",
            "paulatim",
            "pecus",
            "persto",
            "pertineo",
            "plaga",
            "pneum",
            "populus",
            "praemitto",
            "praesent",
            "premo",
            "probo",
            "proprius",
            "quadrum",
            "quae",
            "qui",
            "quia",
            "quibus",
            "quidem",
            "quidne",
            "quis",
            "ratis",
            "refero",
            "refoveo",
            "roto",
            "rusticus",
            "saepius",
            "sagaciter",
            "saluto",
            "scisco",
            "secundum",
            "sed",
            "si",
            "similis",
            "singularis",
            "sino",
            "sit",
            "sudo",
            "suscipere",
            "suscipit",
            "tamen",
            "tation",
            "te",
            "tego",
            "tincidunt",
            "torqueo",
            "tum",
            "turpis",
            "typicus",
            "ulciscor",
            "ullamcorper",
            "usitas",
            "ut",
            "utinam",
            "utrum",
            "uxor",
            "valde",
            "valetudo",
            "validus",
            "vel",
            "velit",
            "veniam",
            "venio",
            "vereor",
            "vero",
            "verto",
            "vicis",
            "vindico",
            "virtus",
            "voco",
            "volutpat",
            "vulpes",
            "vulputate",
            "wisi",
            "ymo",
            "zelus",
        ];
        // cSpell:enable
        $dictionary_flipped = array_flip($dictionary);
        $greeking = '';
        if (!$capitalize) {
            $words_remaining = $min_word_count;
            while ($words_remaining > 0) {
                $sentence_length = mt_rand(3, 10);
                $words = array_rand($dictionary_flipped, $sentence_length);
                $sentence = implode(' ', $words);
                $greeking .= ucfirst($sentence) . '. ';
                $words_remaining -= $sentence_length;
            }
        }
        else {
            // Use slightly different method for titles.
            $words = array_rand($dictionary_flipped, $min_word_count);
            $words = is_array($words) ? implode(' ', $words) : $words;
            $greeking = ucwords($words);
        }
        return trim($greeking);
    }
    
    /**
     * Generate paragraphs separated by double new line.
     *
     * @param int $paragraph_count
     *   The number of paragraphs to create. Defaults to 12.
     *
     * @return string
     */
    public function paragraphs($paragraph_count = 12) {
        $output = '';
        for ($i = 1; $i <= $paragraph_count; $i++) {
            $output .= $this->sentences(mt_rand(20, 60)) . "\n\n";
        }
        return $output;
    }
    
    /**
     * Create a placeholder image.
     *
     * @param string $destination
     *   The absolute file path where the image should be stored.
     * @param string $min_resolution
     *   The minimum dimensions for the image. For example, '400x300'.
     * @param string $max_resolution
     *   The maximum dimensions for the image. For example, '800x600'.
     *
     * @return string
     *   Path to image file.
     */
    public function image($destination, $min_resolution, $max_resolution) {
        $extension = pathinfo($destination, PATHINFO_EXTENSION);
        $min = explode('x', $min_resolution);
        $max = explode('x', $max_resolution);
        $width = rand((int) $min[0], (int) $max[0]);
        $height = rand((int) $min[1], (int) $max[1]);
        // Make an image split into 4 sections with random colors.
        $im = imagecreate($width, $height);
        for ($n = 0; $n < 4; $n++) {
            $color = imagecolorallocate($im, rand(0, 255), rand(0, 255), rand(0, 255));
            $x = $width / 2 * ($n % 2);
            $y = $height / 2 * (int) ($n >= 2);
            imagefilledrectangle($im, (int) $x, (int) $y, (int) ($x + $width / 2), (int) ($y + $height / 2), $color);
        }
        // Make a perfect circle in the image middle.
        $color = imagecolorallocate($im, rand(0, 255), rand(0, 255), rand(0, 255));
        $smaller_dimension = min($width, $height);
        imageellipse($im, (int) ($width / 2), (int) ($height / 2), $smaller_dimension, $smaller_dimension, $color);
        $save_function = 'image' . ($extension == 'jpg' ? 'jpeg' : $extension);
        $save_function($im, $destination);
        return $destination;
    }

}