<?php
/**
 * Class to manipulate function require to simulate UNIX grep command
 */

$count = 0;
static $fileCounter = 0;

$fileSearched = array();
$dir_arr = array() ;
$dir_file = array() ;
$arrayOfOccurrence = array();
$arrayOfFilenames = array();

class ClassForGrep {
      
    private static $instance = 0;

    /**
	 * returns an instance of the ClassForGrep object.
	 * @access public
	 * @static
	 *
	 */

	public static function getInstance() {
		if (ClassForGrep::$instance === 0) {
			ClassForGrep::$instance = new ClassForGrep();
		}
		return ClassForGrep::$instance;
	}

    public $classForGrep;

	/**
	 * creates a new ClassForGrep object.
	 * @access protected
	 */ 
	public function __construct() {
		return $this->classForGrep;
	}

    /**
     * to create and array of extentions
     *
     *
     * @param $separator string/char
     * @param $filesWithExtentionsToBeSearched string
     *
     * @return array
     */
    public function createArrayOfExtentions($separator,$filesWithExtentionsToBeSearched) {
        $arrayOfExtentions = explode($separator,$filesWithExtentionsToBeSearched);
        foreach($arrayOfExtentions as $items ) {
            $newArrayOfExtentions[] = trim($items);
        }
        return $newArrayOfExtentions;
    }
                
    /**
     *
     * function to convert time in secs into mins
     *
     * @param $timeInSec int
     *
     * $return string
     */
     
    public function convertSecToMins($timeInSec) {
        if( $timeInSec < 60 ) {
            if( $timeInSec > 1) {        
                $secString = "secs";            
            }
            else {
                $secString = "sec";            
            }
            $timeTaken = "$timeInSec $secString";
        }
        else {  
            $seconds = ($timeInSec % 60);
            $minutes = ($timeInSec/60);
            $minutes = sprintf("%01.0f", $minutes);

            if( $minutes > 1) {        
                $minString = "mins";            
            }
            else {
                $minString = "min";            
            }
            
            if( $seconds > 1) {        
                $secString = "secs";            
            }
            else {
                $secString = "sec";            
            }
            $timeTaken = "$minutes $minString $seconds $secString";
        }  
        
        return $timeTaken;
    }


    /**
     *
     * function to replace last occurrences of the search string with 
     * the replacement string .  
     *
     * @param $search mixed
     * @param $replace mixed
     * @param $subject mixed
     *
     * $return mixed
     */
     
    public function last_str_replace($search, $replace, $subject) {
        $positionOfLastString = strrpos($subject,$search);
        $stingBeforeSearchSting = substr($subject, 0, $positionOfLastString)." "; 
        $stingAfterSearchSting = substr($subject, $positionOfLastString+1, strlen($subject)); 
        return $newString = $stingBeforeSearchSting.$replace.$stingAfterSearchSting;
    }

    
    /**
    *
    * function to read a directory recursively and finds a string in all the files.
    * it also returns the number of times a sting was found in a file
    *
    * @param $path string
    *
    * @return mixed
    */

    public function read_dir($path) {
        global $dir_arr,$dir_file,$dir_path,$ptr,$fileSearched,$searchString,$replaceString,$fileCounter,$arrayOfOccurrence,$arrayOfFilenames,$filesWithExtentionsToBeSearched,$newArrayOfExtentions;
        $handle = @opendir($path);
        
        while ($file = @readdir($handle) ) {
                      
            if ( $file != "."  && $file != ".." && is_dir($path.$file)) {                   
                $sub_dir = $path . $file . "/" ;
                array_push($dir_arr,$file) ;       
                $this->read_dir($sub_dir);
            }
            elseif ($file != "." && $file != ".." && is_file($path.$file)) {                   
               $sub_dir = $path . $file  ;
               $temp = explode(".",$file);
               $ext = end($temp);
               $file_path = $sub_dir;		            
               $display_filename = str_replace($scan_dir, './',$file_path);

                // start searching and replacing	

                //  searches only files extention in the given array
                if(in_array(trim($ext),$newArrayOfExtentions) ) {
                    $fileContents=file_get_contents($file_path);
                    if(substr_count($fileContents,$searchString)) {
                        array_push($arrayOfFilenames,$display_filename);
                        array_push($arrayOfOccurrence,substr_count($fileContents,$searchString));
                        $fileCounter++;
                    }                    
                    array_push($dir_file,$file) ;       
                }
               
            }

        }
        return $fileCounter;
    }
}
?>