Truncate text without truncating html

pi.eme_utills.php

<?php 
/* Plugin for expression engine 2 */
if (!defined('BASEPATH')) exit('No direct script access allowed');
/*
========================================================
Plugin Eme Utills
--------------------------------------------------------
Copyright: Udit Rawat
License: Freeware
--------------------------------------------------------
This addon may be used free of charge. Should you
employ it in a commercial project of a customer or your
own I'd appreciate a small donation.
========================================================
File: pi.eme_utills.php
--------------------------------------------------------
Purpose: Special function supporting ee templates
========================================================
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO
EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
OR OTHER DEALINGS IN THE SOFTWARE.
========================================================
*/

$plugin_info = array(
    'pi_name' => 'EME_Utills',
    'pi_version' => '1.0',
    'pi_author' => 'Udit Rawat',
    'pi_author_url' => 'http://emerico.in',
    'pi_description' => 'String / Array and some special function support for ee template',
    'pi_usage' => EME_Utills::usage()
);

class EME_Utills
{

    public static function usage()
    {

        ob_start();
        ?>
        Documentation available for developer only
        <?php
        $buffer = ob_get_contents();
        ob_end_clean();
        return $buffer;
    }

    function Trunchtml()
    {
        $this->EE =& get_instance();

        $text = $this->EE->TMPL->tagdata;

        $chars = $this->EE->TMPL->fetch_param('chars', '500');
        $ending = $this->EE->TMPL->fetch_param('ending', '');
        $isHTML = $this->EE->TMPL->fetch_param('html', true);

        $text = trim(preg_replace('/\s\s+/', ' ', $text));
        $s = trim($text);
        $l = $chars;
        $e = (strlen(strip_tags($s)) > $chars) ? $ending : '';
        $i = 0;
        $tags = array();

        if($isHTML) {
            preg_match_all('/<[^>]+>([^<]*)/', $s, $m, PREG_OFFSET_CAPTURE | PREG_SET_ORDER);
            foreach($m as $o) {
                if($o[0][1] - $i >= $l) {
                    break;
                }
                $t = substr(strtok($o[0][0], " \t\n\r\0\x0B>"), 1);
                if($t[0] != '/') {
                    $tags[] = $t;
                }
                elseif(end($tags) == substr($t, 1)) {
                    array_pop($tags);
                }
                $i += $o[1][1] - $o[0][1];
            }
        }
        $output = substr($s, 0, $l = min(strlen($s), $l + $i)) . (count($tags = array_reverse($tags)) ? '</' . implode('></', $tags) . '>' : '') . $e;

        return $output;
    }
}
/*
Usage:
{exp:fws_utills:trunchtml chars="50"}
  {product_excerpt}
{/exp:fws_utills:trunchtml}

truncate-text.php

<?php
function truncate_html($s, $l, $e = '&hellip;', $isHTML = true) {
    $s = trim($s);
    $e = (strlen(strip_tags($s)) > $l) ? $e : '';
    $i = 0;
    $tags = array();

    if($isHTML) {
        preg_match_all('/<[^>]+>([^<]*)/', $s, $m, PREG_OFFSET_CAPTURE | PREG_SET_ORDER);
        foreach($m as $o) {
            if($o[0][1] - $i >= $l) {
                break;                  
            }
            $t = substr(strtok($o[0][0], " \t\n\r\0\x0B>"), 1);
            if($t[0] != '/') {
                $tags[] = $t;                   
            }
            elseif(end($tags) == substr($t, 1)) {
                array_pop($tags);                   
            }
            $i += $o[1][1] - $o[0][1];
        }
    }
    $output = substr($s, 0, $l = min(strlen($s), $l + $i)) . (count($tags = array_reverse($tags)) ? '</' . implode('></', $tags) . '>' : '') . $e;
    return $output;
}
/*
Usage:
truncate_html('<p>Smak av mango, limonade og brunt sukker</p> cool! it working for me', 24);