Untitled

<?php

session_start();
error_reporting(E_ALL);
ini_set('display_errors', '1');
 ?>
<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <style>
    table {
    margin-top:3%;
    border-collapse: collapse;
    }

    table, th, td {
    border: 1px solid black;
    }

    td{
    padding:5px;
    }
    a{
    color:black;

    cursor:pointer;
    }
    .head{
    top: 0px;
    border-bottom:3px solid black;
    text-align:center;
    font-weight: bold;
    font-size:110%;
    }
    </style>
    <meta charset="utf-8">
    <title></title>
  </head>
  <body>

    <?php
    const DSN = "mysql:host=localhost;dbname=blog;charset=utf8";
    const USER = "root";
    const PASS= "";
      if (isset($_POST["odhlasit"])) {
        unset($_SESSION["login"]);
      }
      if (isset($_POST['odeslat'])) {
        $heslo = login($_POST['login']);
        if (!$heslo || $heslo[0]["pass"] !== $_POST["pass"]) {
          echo "Login nebo heslo je špatně";
        }else{
        if ($heslo[0]["pass"] == $_POST["pass"]) {
          echo "Přihlášení proběhlo úspěšně";
          header('Location:'.$_SERVER['PHP_SELF']);
          $_SESSION["login"] = $_POST['login'];
          $_SESSION["id_uzivatele"] =  $heslo[0]["id_uzivatele"];
        }
      }
    }
    var_dump ($_SESSION);

function login($log)
{
      $db = new PDO(DSN, USER, PASS);
      $stmt = $db->prepare("SELECT pass, passhash, id_uzivatele FROM uzivatele WHERE login = :jmeno");
      $stmt -> execute([
        ":jmeno" => $log
        ]);
        $tabulka=$stmt->fetchAll(PDO::FETCH_ASSOC);
        return $tabulka;

};
function checknameunique(){
    $db = new PDO(DSN, USER, PASS);
    $stmt = $db->prepare("SELECT login FROM uzivatele WHERE login = :jmeno");
    $stmt->execute([
        ":jmeno" => $_POST["name"],
    ]);
    $jmeno=$stmt->fetchAll(PDO::FETCH_ASSOC);
    if(isset($jmeno[0]["login"])){
        return true;
    }
    return false;
}
function vloz(){
try {
     $db = new PDO(DSN, USER, PASS);
     $stmt = $db -> prepare("INSERT INTO posty (nadpis, text, id_uzivatele)
     VALUES (:nadpis, :text, :id_uzivatele)");
     $stmt -> execute([
     ":nadpis" => $_POST["nadpis"],
     ":text" => $_POST["post"],
     ":id_uzivatele" => $_SESSION["id_uzivatele"]
   ]);
 }
 catch(PDOException $e){
    echo $e->getMessage();

}
};


   ?>
   <form method="post">
     <p>Registrace</p>

<form action="" method="post">
 <div class="inputs">
 <input type="text" maxlength="14" name="name" placeholder="Login"><br>
 <input type="password" name="passreg" placeholder="Heslo"><br>
 <input type="password" name="passreg2" placeholder="Heslo znovu"><br>


 </div>
 <input type="submit" value="registrovat" name="regist">
<p>Přihlášení</p>
     <input type="text" name="login" value="" placeholder="Login"><br />
     <input type="password" name="pass" value="" placeholder="Heslo"><br />
     <input type="submit" name="odeslat" value="Přihlásit">
     <?php
       if (isset($_POST["postsubmit"])) {
         vloz();
         header('Location:'.$_SERVER['PHP_SELF']);
         exit;

       }

       if (isset($_SESSION["login"])) {
         echo "<input type='submit' name= 'odhlasit' value= 'Odhlásit' />";
         echo "<p></p>";
         echo "<br/><input type='text' name='nadpis' value='' placeholder='Nadpis' />";
         echo "<br /><textarea rows='20' cols='70' name='post'></textarea>";
         echo "<br /><input type='submit' name='postsubmit' value='Vytvořit post' />";
         ?>

         <?php
       };
       if (isset($_SESSION["login"])) {
         $db = new PDO(DSN, USER, PASS);
         $stmt = $db->prepare("SELECT nadpis, text, login FROM posty, uzivatele WHERE posty.id_uzivatele = uzivatele.id_uzivatele");
         $stmt -> execute([
         ]);
           $tabulka=$stmt->fetchAll(PDO::FETCH_ASSOC);

           echo '<table>';
           for ($i = 0; $i < count($tabulka); $i++) {
               echo "<tr>";
               foreach ($tabulka[$i] as $key => $value) {
                   echo "<td><br />";
                   echo $tabulka[$i][$key]. "<br/>";
                   echo "</td>";
               }
               if ($_SESSION["login"] == $tabulka[$i]["login"] || $_SESSION["id_uzivatele"] == 1) {
                 echo "<td><a href='editblogpostu.php'>Upravit</td>";
               }

               echo "</tr>";
           }
           echo '</table>';


       };

if (isset($_POST["regist"])) {
  if (!isset($_POST["name"]) || trim($_POST["name"]) == '') {
    echo "Nevyplnil si pole Login" . "<br>";
  }
  if (!isset($_POST["passreg"]) || trim($_POST["passreg"]) == '') {
    echo "Nevyplnil si pole Heslo" . "<br>";
  }
  if (!isset($_POST["passreg2"]) || trim($_POST["passreg2"]) == '') {
    echo "Nevyplnil si pole Heslo znovu" . "<br>";
  }
  if(checknameunique()==false){
 if($_POST["passreg"] !== $_POST["passreg2"] || $_POST["name"] == '' || $_POST["passreg"] == ''){
     $_POST["passreg2"] = "";
     $_POST["name"] = "";
     $_POST["passreg"] = "";
 }else {
     $db = new PDO(DSN, USER, PASS);
     $stmt = $db -> prepare("INSERT INTO uzivatele (login,passhash,pass)
     VALUES (:loginjmeno,:passhash, :passregist)");
     $stmt -> execute([
     ":loginjmeno" => $_POST["name"],
     ":passhash" => password_hash($_POST["passregist"], PASSWORD_DEFAULT),
     ":passregist" => $_POST["passreg"]
   ]);
 }
 }else
 echo "Zadané jméno je už použito";
 header('Location:'.$_SERVER['PHP_SELF']);
 exit;
 }

      ?>

   </form>
  </body>

</html>