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<html>
<head>
    <title>Code snippet forum-Login page</title>
  <script src='https://www.google.com/recaptcha/api.js'></script>
    <?php
     session_start();
     session_destroy();
     $link = mysqli_connect("127.0.0.1", "root", "", "delta");
     require_once "recaptchalib.php";
     session_start();
     if(!$link){
      echo "Could not connect";
      echo mysqli_error($link);
     }
     else{
      echo "Sucesssfully connected";
      if(isset($_POST["login"])){
        if(isset($_POST["username"])){
            $username = mysqli_real_escape_string($link,$_POST["username"]);
            $username = stripslashes($username);
         }
        if(isset($_POST["password"])){
              $password = mysqli_real_escape_string($link,$_POST["password"]);
            $password = stripslashes($password);

            }
        $secret = "6Le_iScUAAAAADkT6a-7dPnEBjWKhmMls2tOxJql";

      // empty response
        $response = null;

      // check secret key
         $reCaptcha = new ReCaptcha($secret);
          if ($_POST["g-recaptcha-response"]) {
          $response = $reCaptcha->verifyResponse(
          $_SERVER["REMOTE_ADDR"],
          $_POST["g-recaptcha-response"]
        );
      }
        $password_hash = hash('md5',$password);
        $query = "SELECT * FROM user_info WHERE username = '".$username."' AND password = '".$password_hash."'";
        $sql = mysqli_query($link,$query);
        $rows = mysqli_num_rows($sql);
        if($rows==1&&$response != null&&$response->success){
            echo "  Sucessfully logged in";
            $_SESSION["username"] = $username;
            header("Location: insert.php");
        }
        else{
            echo "  Invalid username or password";
        }

      }
     }
    ?>


</head>
<style type="text/css">
   .login{
     border: 2px solid black;
     border-radius: 6px 6px 6px 6px;
     padding: 15px 15px 15px 15px;
     margin right: 400px;
     margin-top: 210px;
     margin-left: 310px;
     width: 450px;
     font-size: 20px;
   }
   body {
    font: 13px/20px "Lucida Grande", Tahoma, Verdana, sans-serif;
    color: #404040;
    background: #0ca3d2;
   }

  </style>
<body>
  <div class = "login">
  <form method = "POST" >
    <p>Username: <input type = "text" name = "username" placeholder = 'Enter the username'></p>
    <p>Password: <input type = "text" name = "password" placeholder = "Enter the password"></p>
    <input type = "submit" name = "login" value = "Login">
    <div class="g-recaptcha" data-sitekey="6Le_iScUAAAAAD2UsWWJ0fxKT2LtXk-MXNxR6JXS"></div>
  </form>
  <a href = "register.php">Click here to register</a>
</div>
<a href="list.php">This is the list of all snippets</a>
</body>
</html>