Core\Traits\StringFunctions

Complexity

Total Complexity

22

Size/Duplication

Total Lines	171
Duplicated Lines	0 %

Importance

Changes

0

11 Methods

Rating	Name	Duplication	Size	Complexity
A	isInt()	0	3	1
A	isAlphaNum()	0	3	1
A	endsWith()	0	8	2
A	isEmail()	0	3	1
A	completeDom()	0	5	1
A	startsWith()	0	4	1
A	isHexa()	0	3	1
A	removeFromEnd()	0	6	2
A	removeFromBeginning()	0	6	2
A	isAllAlphaNum()	0	11	3
B	getExcerpt()	0	36	7

<?php

namespace Core\Traits;

use Core\Constant;
use HTMLPurifier;
use HTMLPurifier_Config;

/**
 * a trait with some string related helpers
 * Trait StringFunctions
 * @package Core\Traits
 */
trait StringFunctions
{
    /**
     * does a haystack start with a needle ?
     * @param $haystack string the string to search in
     * @param $needle string the string to search for
     * @return bool
     */
    public function startsWith(string $haystack, string $needle): bool
    {
        $length = strlen($needle);
        return (substr($haystack, 0, $length) === $needle);
    }

    /**
     * Does a haystack end with a needle
     * @param $haystack string the string to search in
     * @param $needle string the string to search for
     * @return bool
     */
    public function endsWith(string $haystack, string $needle): bool
    {
        $length = strlen($needle);
        if ($length == 0) {
            return true;
        }

        return (substr($haystack, -$length) === $needle);
    }

    /**
     * Remove the tail of a string
     * @param $string string to slice apart
     * @param $tail string the string to remove
     * @return string
     */
    public function removeFromEnd(string $string, string $tail): string
    {
        if ($this->endsWith($string, $tail)) {
            $string = substr($string, 0, -strlen($tail));
        }
        return $string;
    }

    /**
     * remove some characters from the front of the string
     * @param string $string the string to be decapitated
     * @param string $head the head to be cut off ("OFF WITH HIS HEAD")
     * @return string
     */
    public function removeFromBeginning(string $string, string $head): string
    {
        if ($this->startsWith($string, $head)) {
            $string = substr($string, strlen($head));
        }
        return $string;
    }

    /**
     * create an excerpt, shortening the text to a specific number of words
     * @param string $text the text to shorten
     * @param int $count number of words
     * @return string the shortend text
     * @throws \ErrorException
     */
    public function getExcerpt(string $text, int $count = Constant::EXCERPT_WORD_COUNT):string
    {
        if ($count < 1) {
            throw new \ErrorException('excerpt length too low');
        }
        $text = str_replace("  ", " ", $text);

        //Searching for the page break tag
        $breakTagPosition = strpos($text, "<!-- EndOfExcerptBlogOc -->");
        if($breakTagPosition > 0){
            return $this->completeDom(substr($text, 0, $breakTagPosition));
        }

        //exploding on space except for in img, p and span.
        $string = preg_split('/(<img[^>]+\>)|(<p[^>]+\>)|(<span[^>]+\>)|\s/', $text, -1, PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE);

        //The preg split can return false, probably will never happen but just in case.
        if(!$string)
        {
            throw new \Error("excerpt generation failed");
        }

        if (count($string) <= $count) {
            return $text;
        }
        $trimmed = '';
        for ($wordCounter = 0; $wordCounter < $count; $wordCounter++) {
            $trimmed .= $string[$wordCounter];
            if ($wordCounter < $count - 1) {
                $trimmed .= " ";
            } else {
                $trimmed .= "[...]";
            }
        }

        return $this->completeDom($trimmed);
    }

    /**
     * Close the dom in given $text
     * @param string $text unclean html
     * @return string cleaned up html
     */
    private function completeDom(string $text): string
    {
        $config = HTMLPurifier_Config::createDefault();
        $purifier = new HTMLPurifier($config);
        return $purifier->purify($text);
    }

    /**
     * check passed string, returns true if the string contains alphaNum or _ or -. use for checking database tables, column names or slugs
     * @param string $string the string to analyse
     * @return bool
     */
    public function isAlphaNum(string $string): bool
    {
        return preg_match("/^[A-Za-z0-9_-]+$/", $string) === 1;
    }

    /**
     * check if each string in passed array is valid
     * @param array $strings
     * @return bool
     */
    public function isAllAlphaNum(array $strings):bool
    {
        $result = true;
        foreach ($strings as $string)
        {
            if(!$this->isAlphaNum($string))
            {
                $result = false;
            }
        }
        return $result;
    }

    /**
     * check is a string is hexadecimal
     * @param string $string
     * @return bool
     */
    public function isHexa(string $string):bool
    {
        return preg_match("/[\da-f]/",$string) === 1;
    }

    /**
     * check if the sent var is an integer
     * @param $int
     * @return bool
     */
    public function isInt($int):bool
    {
        return filter_var($int, FILTER_VALIDATE_INT) !== false;
    }

    /**
     * Verify if a string is a valid email
     * @param string $email
     * @return bool
     */
    public function isEmail(string $email):bool
    {
        return filter_var($email, FILTER_VALIDATE_EMAIL) !== false;
    }

}