Lorem generator in PHP

Lorem.php

<?php
// by user @mpen - https://stackoverflow.com/a/39986034/528020
// usage: Lorem::ipsum(4);
abstract class Lorem {
    public static function ipsum($nparagraphs) {
        $paragraphs = [];
        for($p=0; $p<$nparagraphs; ++$p) {
            $nsentences = random_int(3,8);
            $sentences = [];
            for($s=0; $s<$nsentences; ++$s) {
                $frags = [];
                $commaChance = .33;
                while(true) {
                    $nwords = random_int(3, 15);
                    $words = self::random_values(self::$lorem, $nwords);
                    $frags[] = implode(' ', $words);
                    if(self::random_float() >= $commaChance) {
                        break;
                }
                $commaChance /= 2;
            }
            
            $sentences[] = ucfirst(implode(', ', $frags)) . '.';
        }
        $paragraphs[] = implode(' ',$sentences);
    }
    return implode("\n\n",$paragraphs);
}

private static function random_float() {
    return random_int(0, PHP_INT_MAX-1)/PHP_INT_MAX;
}

private static function random_values($arr, $count) {
    $keys = array_rand($arr, $count);
    if($count == 1) {
        $keys = [$keys];
    }
    return array_intersect_key($arr, array_fill_keys($keys, null));
}

private static $lorem = [
0 => 'lorem',
1 => 'ipsum',
2 => 'dolor',
3 => 'sit',
4 => 'amet',
5 => 'consectetur',
6 => 'adipiscing',
7 => 'elit',
8 => 'praesent',
9 => 'interdum',
10 => 'dictum',
11 => 'mi',
12 => 'non',
13 => 'egestas',
14 => 'nulla',
15 => 'in',
16 => 'lacus',
17 => 'sed',
18 => 'sapien',
19 => 'placerat',
20 => 'malesuada',
21 => 'at',
22 => 'erat',
23 => 'etiam',
24 => 'id',
25 => 'velit',
26 => 'finibus',
27 => 'viverra',
28 => 'maecenas',
29 => 'mattis',
30 => 'volutpat',
31 => 'justo',
32 => 'vitae',
33 => 'vestibulum',
34 => 'metus',
35 => 'lobortis',
36 => 'mauris',
37 => 'luctus',
38 => 'leo',
39 => 'feugiat',
40 => 'nibh',
41 => 'tincidunt',
42 => 'a',
43 => 'integer',
44 => 'facilisis',
45 => 'lacinia',
46 => 'ligula',
47 => 'ac',
48 => 'suspendisse',
49 => 'eleifend',
50 => 'nunc',
51 => 'nec',
52 => 'pulvinar',
53 => 'quisque',
54 => 'ut',
55 => 'semper',
56 => 'auctor',
57 => 'tortor',
58 => 'mollis',
59 => 'est',
60 => 'tempor',
61 => 'scelerisque',
62 => 'venenatis',
63 => 'quis',
64 => 'ultrices',
65 => 'tellus',
66 => 'nisi',
67 => 'phasellus',
68 => 'aliquam',
69 => 'molestie',
70 => 'purus',
71 => 'convallis',
72 => 'cursus',
73 => 'ex',
74 => 'massa',
75 => 'fusce',
76 => 'felis',
77 => 'fringilla',
78 => 'faucibus',
79 => 'varius',
80 => 'ante',
81 => 'primis',
82 => 'orci',
83 => 'et',
84 => 'posuere',
85 => 'cubilia',
86 => 'curae',
87 => 'proin',
88 => 'ultricies',
89 => 'hendrerit',
90 => 'ornare',
91 => 'augue',
92 => 'pharetra',
93 => 'dapibus',
94 => 'nullam',
95 => 'sollicitudin',
96 => 'euismod',
97 => 'eget',
98 => 'pretium',
99 => 'vulputate',
100 => 'urna',
101 => 'arcu',
102 => 'porttitor',
103 => 'quam',
104 => 'condimentum',
105 => 'consequat',
106 => 'tempus',
107 => 'hac',
108 => 'habitasse',
109 => 'platea',
110 => 'dictumst',
111 => 'sagittis',
112 => 'gravida',
113 => 'eu',
114 => 'commodo',
115 => 'dui',
116 => 'lectus',
117 => 'vivamus',
118 => 'libero',
119 => 'vel',
120 => 'maximus',
121 => 'pellentesque',
122 => 'efficitur',
123 => 'class',
124 => 'aptent',
125 => 'taciti',
126 => 'sociosqu',
127 => 'ad',
128 => 'litora',
129 => 'torquent',
130 => 'per',
131 => 'conubia',
132 => 'nostra',
133 => 'inceptos',
134 => 'himenaeos',
135 => 'fermentum',
136 => 'turpis',
137 => 'donec',
138 => 'magna',
139 => 'porta',
140 => 'enim',
141 => 'curabitur',
142 => 'odio',
143 => 'rhoncus',
144 => 'blandit',
145 => 'potenti',
146 => 'sodales',
147 => 'accumsan',
148 => 'congue',
149 => 'neque',
150 => 'duis',
151 => 'bibendum',
152 => 'laoreet',
153 => 'elementum',
154 => 'suscipit',
155 => 'diam',
156 => 'vehicula',
157 => 'eros',
158 => 'nam',
159 => 'imperdiet',
160 => 'sem',
161 => 'ullamcorper',
162 => 'dignissim',
163 => 'risus',
164 => 'aliquet',
165 => 'habitant',
166 => 'morbi',
167 => 'tristique',
168 => 'senectus',
169 => 'netus',
170 => 'fames',
171 => 'nisl',
172 => 'iaculis',
173 => 'cras',
174 => 'aenean',
];
}