[Laravel] Support method to convert a given string to a searchable string (ascii+lowercase), according to the given minimum length.

Str.php

<?php

namespace App\Support;

class Str extends \Illuminate\Support\Str
{
    /**
     * Returns the searchable string.
     *
     * @param string    $string String to convert
     * @param bool      $replace Replace spaces
     * @param int       $min Minimum length of searchable string
     * @param string    $replaceWith Replace spaces with given string
     * @return string $string
     */
    public static function searchable($string, $replace = false, $min = 3, $replaceWith = '%')
    {
        // Remove duplicated spaces
        $string = preg_replace('/\s+/', ' ', self::lower(self::ascii(trim($string))));
        $splitString = explode(' ', $string);

        $terms = array_filter($splitString, function($term) use ($min) {
            return strlen($term) >= $min;
        });

        // There are terms that respect the minimum length, concatenate them and use it as search string.
        if(count($terms) > 0) {
            return implode($replace ? $replaceWith : ' ', $terms);
        }

        return $string;
    }
}

Examples (with default parameters):

'wõrd' => 'word'
'a string' => 'string'
'search string' => 'search string' 
'   a    spaced    string  ' => 'spaced string' // filter terms with length < $min
'a  a' => 'a a' // there are no terms with length >= $min
...

When $replace = true;, spaces are replaced with $replaceWith.

'search string' => 'search%string'
'   a    spaced    string  ' => 'spaced%string' // filter terms with length < $min
'a a' => 'a a' // there are no terms with length >= $min, do not replace
...