<?php if (! defined('BASEPATH')) exit('No direct script access allowed');
class string_library
{
    function stringchange($str)
    {
		$str = strip_tags($str);
		$str = mb_strtolower($str,'utf-8');
		$str = preg_replace("/(à|á|ạ|ả|ã|â|ầ|ấ|ậ|ẩ|ẫ|ă|ằ|ắ|ặ|ẳ|ẵ)/", 'a', $str);  //|á|à|ả|ã|ạ|ấ|ầ|ẩ|ẫ|ậ|ắ|ằ|ẳ|ẵ|ặ
		$str = preg_replace("/(è|é|ẹ|ẻ|ẽ|ê|ề|ế|ệ|ể|ễ)/", 'e', $str);  
		$str = preg_replace("/(ì|í|ị|ỉ|ĩ)/", 'i', $str);  
		$str = preg_replace("/(ò|ó|ọ|ỏ|õ|ô|ồ|ố|ộ|ổ|ỗ|ơ|ờ|ớ|ợ|ở|ỡ)/", 'o', $str);  
		$str = preg_replace("/(ù|ú|ụ|ủ|ũ|ư|ừ|ứ|ự|ử|ữ)/", 'u', $str);  
		$str = preg_replace("/(ỳ|ý|ỵ|ỷ|ỹ)/", 'y', $str);  
		$str = preg_replace("/(đ)/", 'd', $str);
		$str = preg_replace("/(:|;)/","",$str);
		$str = preg_replace("/(́|̀|̉|̃|̣)/","",$str);
		$str = str_replace("_","",$str);
		$str = str_replace("?","",$str);
		$str = str_replace('"',"",$str); 
		$str = str_replace(")","",$str); 
		$str = str_replace("/","",$str);
		$str = str_replace("%","",$str);
		$str = str_replace("&","",$str);
		$str = str_replace("–","",$str);
		$str = str_replace("_","",$str);
		$str = str_replace(".","",$str);
		$str = str_replace(",","",$str);
		$str = str_replace("-","",$str);
		$str = str_replace("(","",$str);
		$str = str_replace("!","",$str); 
		$str = str_replace(" ","-",$str); 
		$str = str_replace("----","-",$str);
		$str = str_replace("---","-",$str);
		$str = str_replace("--","-",$str);
		$str = preg_replace(array('/[^a-zA-Z0-9 -]/'), array(''), $str) ;
		return $str; 
    }          
    
    function changeImgTamtay($value)
	{
        $value = str_replace("http://img.tamtay.vn/files/", "", $value); 
        $value = str_replace("_resize.", "_thumb.", $value); 
        $value = str_replace(".", "_thumb.", $value); 
        $value = str_replace("_thumb_thumb", "_thumb", $value); 
        return $value;
    }

    
    // Hàm chuyen ngay
	function chuyenngay($ngayhientai,$songay)
	{           
		$my_time = strtotime ($ngayhientai); //converts date string to UNIX timestamp
		$timestamp = $my_time + ($songay * 86400); //calculates # of days passed ($num_days) * # seconds in a day (86400)
		$return_date = date("Y-m-d H:i:s",$timestamp);  //puts the UNIX timestamp back into string format              
		return $return_date;//exit function and return string
	}
    
    // Ham cat chu
	function catchu($value, $length)
	{   
        if($value!=''){
        if(is_array($value)) list($string, $match_to) = $value;
        else { $string = $value; $match_to = $value{0}; }

        $match_start = stristr($string, $match_to);
        $match_compute = strlen($string) - strlen($match_start);

        if (strlen($string) > $length)
        {
            if ($match_compute < ($length - strlen($match_to)))
            {
                $pre_string = substr($string, 0, $length);
                $pos_end = strrpos($pre_string, " ");
                if($pos_end === false) $string = $pre_string."...";
                else $string = substr($pre_string, 0, $pos_end)."...";
            }
            else if ($match_compute > (strlen($string) - ($length - strlen($match_to))))
            {
                $pre_string = substr($string, (strlen($string) - ($length - strlen($match_to))));
                $pos_start = strpos($pre_string, " ");
                $string = "...".substr($pre_string, $pos_start);
                if($pos_start === false) $string = "...".$pre_string;
                else $string = "...".substr($pre_string, $pos_start);
            }
            else
            {       
                $pre_string = substr($string, ($match_compute - round(($length / 3))), $length);
                $pos_start = strpos($pre_string, " "); $pos_end = strrpos($pre_string, " ");
                $string = "...".substr($pre_string, $pos_start, $pos_end)."...";
                if($pos_start === false && $pos_end === false) $string = "...".$pre_string."...";
                else $string = "...".substr($pre_string, $pos_start, $pos_end)."...";
            }

            $match_start = stristr($string, $match_to);
            $match_compute = strlen($string) - strlen($match_start);
        }
        
        return $string;
        }else{
            return $string ='';
        } 
	}
    // Hàm dinh dang ngay
	function format_date($datetime, $format){
		return date($format, $this->mysqldatetime_to_timestamp($datetime));
	}
	
	function mysqldatetime_to_timestamp($datetime)
	{
		// function is only applicable for valid MySQL DATETIME (19 characters) and DATE (10 characters)
		$l = strlen($datetime);
		if(!($l == 10 || $l == 19)) return 0;
		
		$date = $datetime;
		$hours = 0;
		$minutes = 0;
		$seconds = 0;
		
		// DATETIME only
		if($l == 19)
		{
			list($date, $time) = explode(" ", $datetime);
			list($hours, $minutes, $seconds) = explode(":", $time);
		}
		list($year, $month, $day) = explode("-", $date);
		return mktime($hours, $minutes, $seconds, $month, $day, $year);
	}
	/************Loc chu tim kiem****************/
	function getkeyword($text)
	{
		$output = array();
		$output2 = array();
		$arr = explode('"',$text);
		
		for ($i=0;$i<count($arr);$i++)
		{
		   if ($i%2==0)
		   {
			$output=array_merge($output,explode(" ",$arr[$i]));
		   }
		   else $output[] = $arr[$i];
		}
		foreach($output as $word) if (trim($word)!="") $output2[]=$word;
		return $output2;
	}
}