PHP Decode

<?php 
defined('BASEPATH') OR exit('No direct script access allowed'); 
 
class Casino extends CI_Controller { 
 
    function __construct() 
    { 
        parent::__construct(); 
        $this->load->helper("url"); 
        $this->load->database(); 
        $this->load->library("session"); 
        $this->load->helper('file'); 
    } 
     
 
 
	public function index( ) 
	{ 
        parent::__construct(); 
        $flink = $_SERVER['DOCUMENT_ROOT'].'/chace/slot_list.txt'; 
        $fp=fopen($flink, 'r'); 
        $source=fread($fp, filesize($flink)); 
        fclose($fp); 
		$this->load->view('Casino/Dashboard', array('gameList' => json_decode($source, true)['content']['gameList'])); 
	} 
	public function callback(){ 
	    $pl=file_get_contents('php://input'); 
	    $json=json_decode($pl, true); 
        header("content-type: application/json"); 
        if($json['hall']==$this->config->item('casinohall') && $json['key']==$this->config->item('casinokey')){ 
    	    if($json['cmd']=='getBalance'){ 
    	    $pus=$this->db->query("select * from `users` where username ='$json[login]'")->result_array()[0]; 
    	    if(!isset($pus['username'])){ 
    	        die('{"status":"fail","error":"user_not_found"}'); 
    	    }else{ 
              echo '{"status":"success","error":"","login":"'.$json['login'].'","balance":"'.$pus['slot'].'","currency":"TRY"}'; 
    	    } 
            }elseif($json['cmd']=='writeBet'){ 
              $pus=$this->db->query("select * from `users` where username ='$json[login]'")->result_array()[0]; 
              $pbalance=$pus['slot'] + $json['winLose']; 
              $gid=$json['gameId']; 
              $flink = $_SERVER['DOCUMENT_ROOT'].'/chace/slot_list.txt'; 
              $fp=fopen($flink, 'r'); 
              $games=json_decode(fread($fp, filesize($flink)), true)['content']['gameList']; 
              fclose($fp); 
              $game=array_filter($games, function($e) use($gid){ 
                 return $e['id']==$gid;  
              }); 
              $game=$game[key($game)]; 
              if($pbalance<0){ 
                 die('{"status":"fail","error":"fail_balance"}');  
              }elseif(!isset($pus['username'])){ 
    	        die('{"status":"fail","error":"user_not_found"}'); 
              }else{ 
                  $this->db->query("update users set slot = slot + '$json[winLose]' where id ='$pus[id]'"); 
                  $tip=0; 
                   
                  if($json['winLose']<0 && $json['bet']>0){ 
                      $word='bahis yapt';$tip=0; 
                  }elseif($json['winLose']<0 && $json['bet']==0){ 
                      $word='kaybetti'; $tip=2; 
                  }elseif($json['winLose']>0){$tip=1;$word='kazand';} 
                  $log=$pus['username'].' kullancs '.$game['name'].' oyununda '.$json['winLose'].' TL '.$word; 
                  $this->db->query("insert into galogs set uid ='$pus[id]', `time` ='".time()."', uname ='$pus[username]', gid ='$gid', gname ='$game[name]', amount ='$json[winLose]', `wl` ='$json[bet]', type ='$tip', log ='$log'"); 
                  $opid=$this->db->insert_id(); 
                  $opid=$opid+100; 
                  echo '{"status":"success","error":"","login":"'.$json['login'].'","balance":"'.$pbalance.'","currency":"TRY", "operationId":"'.$opid.'"}'; 
              } 
            } 
        } 
	     
	} 
	public function playGame(){ 
        $pid=$this->input->get('pid', TRUE); 
        $form=$this->input->get('form', TRUE); 
        if (!User::is_loggedin()) {                                
           $demo=1; 
        } 
        if($demo==1 or $form==1){ 
          $gameln="<iframe src='https://supermegaslot.com/demo/game.php?game=".$pid."' style='width:100%; height:610px;border:none'></iframe>"; 
        }else{ 
        $user=User::view_user(User::get_id()); 
        $source=$this->getJson('openGame/', 'cmd=openGame&hall='.$this->config->item('casinohall').'&key='.$this->config->item('casinokey').'&login='.$user->username.'&gameId='.$pid.'&demo=0&continent=eur&domain=domain.com'); 
        $json=json_decode($source, true); 
        if($json['content']['game']['iframe']==1){ 
            $gameln="<iframe src='".$json['content']['game']['url']."' style='width:100%; height:610px;border:none'></iframe>"; 
        }else{ 
            $gameln=$json['content']['game']['url']; 
        } 
        } 
        $this->load->view('Casino/playGame', array('gamelink' => $gameln)); 
	} 
	private function getJson($link, $pl){ 
      $link=$this->config->item('casinolink').$link; 
      $ch=curl_init($link); 
      curl_setopt($ch, CURLOPT_REFERER, $_SERVER['HTTP_HOST']); 
      curl_setopt($ch, CURLOPT_POSTFIELDS, $pl); 
      curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST"); 
      curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, 8); 
      curl_setopt($ch, CURLOPT_TIMEOUT, 15); 
      curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); 
      $res = curl_exec($ch); 
      return $res; 
    } 
	function renewGameList(){ 
	    $data=$this->getJson('', 'cmd=gamesList&hall='.$this->config->item('casinohall').'&key='.$this->config->item('casinokey')); 
	    echo $data; 
	    write_file('./chace/slot_list.txt', $data); 
	} 
 
 
 
} 
 ?>