<?php
// Include config file
require_once "config.php";
 
// Define variables and initialize with empty values
$vokabel = $stammform = $art = $flexion = $uebersetzung = $lektion =$kommentar = "";
$vokabel_err = $stammform_err = $art_err = $flexion_err = $uebersetzung_err = $lektion_err =$kommentar_err = "";

 
// Processing form data when form is submitted
if(isset($_POST["id"]) && !empty($_POST["id"])){
    // Get hidden input value
    $id = $_POST["id"];
    
    // Validate vokabel
    $input_vokabel = trim($_POST["vokabel"]);
    if(empty($input_vokabel)){
        $vokabel_err = "Vokabel eingeben.";
    }  else{
        $vokabel = $input_vokabel;
    }
    
    // Validate  stammform
    $input_stammform = trim($_POST["stammform"]);
    if(empty($input_stammform)){
        $stammform_err = "Bitte Stammform eintragen.";     
    } else{
        $stammform = $input_stammform;
    }
    
    // Validate art
    $input_art = trim($_POST["art"]);
    if(empty($input_art)){
        $art_err = "Bitte Wortart eingeben.";     
    } else{
        $art = $input_art;
    }
    
    // Validate flexion
    $input_flexion = trim($_POST["flexion"]);
    if(empty($input_flexion)){
        $flexion_err = "Bitte Flexion eingeben.";     
    } else{
        $flexion = $input_flexion;
    }

    // Validate uebersetzung
    $input_uebersetzung = trim($_POST["uebersetzung"]);
    if(empty($input_uebersetzung)){
        $uebersetzung_err = "Bitte Übersetzung eingeben.";     
    } else{
        $uebersetzung = $input_uebersetzung;
    }

    // Validate lektion
    $input_lektion = trim($_POST["lektion"]);
    if(empty($input_lektion)){
        $lektion_err = "Bitte Lektion eingeben.";     
    } else{
        $lektion = $input_lektion;
    }

    // Validate kommentar
      $input_kommentar = trim($_POST["kommentar"]);
      if(empty($input_kommentar)){
          $kommentar_err = "Bitte Tipp eingeben.";     
      } else{
          $kommentar = $input_kommentar;
      }
  

    // Check input errors before inserting in database
    if(empty($vokabel_err) && empty($stammform_err) && empty($art_err) 
        &&     empty($flexion_err) &&     empty($uebersetzung_err) &&     empty($lektion_err) &&     empty($kommentar_err) ){
        // Prepare an update statement

        $sql = "UPDATE vokabeln SET vokabel=?, stammform=?, art=?, flexion=?, uebersetzung=?, lektion=?, kommentar=? WHERE id=?";
         
        if($stmt = mysqli_prepare($link, $sql)){
            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "sssssssi", $param_name, $param_stammform, $param_art, $param_flexion, $param_uebersetzung, $param_lektion, $param_kommentar, $param_id);
            
            // Set parameters
            $param_vokabel = $vokabel;
            $param_stammform = $stammform;
            $param_art = $art;
            $param_flexion = $flexion;
            $param_uebersetzung = $uebersetzung;
            $param_lektion = $lektion;
            $param_kommentar = $kommentar;
            
            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){
                // Records updated successfully. Redirect to landing page
                header("location: index.php");
                exit();
            } else{
                echo "Oops! Something went wrong. Please try again later.";
            }
        }
         
        // Close statement
        mysqli_stmt_close($stmt);
    }
    
    // Close connection
    mysqli_close($link);
} else{
    // Check existence of id parameter before processing further
    if(isset($_GET["id"]) && !empty(trim($_GET["id"]))){
        // Get URL parameter
        $id =  trim($_GET["id"]);
        
        // Prepare a select statement
        $sql = "SELECT * FROM vokabeln WHERE id = ?";
        if($stmt = mysqli_prepare($link, $sql)){
            // Bind variables to the prepared statement as parameters
            mysqli_stmt_bind_param($stmt, "i", $param_id);
            
            // Set parameters
            $param_id = $id;
            
            // Attempt to execute the prepared statement
            if(mysqli_stmt_execute($stmt)){
                $result = mysqli_stmt_get_result($stmt);
    
                if(mysqli_num_rows($result) == 1){
                    /* Fetch result row as an associative array. Since the result set
                    contains only one row, we don't need to use while loop */
                    $row = mysqli_fetch_array($result, MYSQLI_ASSOC);
                    
                    // Retrieve individual field value
                    $vokabel = $row["vokabel"];
                    $stammform = $row["stammform"];
                    $art = $row["art"];
                    $flexion = $row["flexion"];
                    $uebersetzung = $row["uebersetzung"];
                    $lektion = $row["lektion"];
                    $kommentar = $row["kommentar"];
                } else{
                    // URL doesn't contain valid id. Redirect to error page
                    header("location: error.php");
                    exit();
                }
                
            } else{
                echo "Oops! Something went wrong. Please try again later.";
            }
        }
        
        // Close statement
        mysqli_stmt_close($stmt);
        
        // Close connection
        mysqli_close($link);
    }  else{
        // URL doesn't contain id parameter. Redirect to error page
        header("location: error.php");
        exit();
    }
}
?>
 
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Update Record</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
    <style>
        .wrapper{
            width: 600px;
            margin: 0 auto;
        }
    </style>
</head>
<body>
    <div class="wrapper">
        <div class="container-fluid">
            <div class="row">
                <div class="col-md-12">
                    <h2 class="mt-5">Update Record</h2>
                    <p>Please edit the input values and submit to update the employee record.</p>
                    <form action="<?php echo htmlspecialchars(basename($_SERVER['REQUEST_URI'])); ?>" method="post">
                        <div class="form-group">
                            <label>Vokabel</label>
                            <input type="text" name="vokabel" class="form-control <?php echo (!empty($vokabel_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $vokabel; ?>">
                            <span class="invalid-feedback"><?php echo $vokabel_err;?></span>
                        </div>
                        <div class="form-group">
                            <label>Stammform</label>
                            <textarea name="stammform" class="form-control <?php echo (!empty($stammform_err)) ? 'is-invalid' : ''; ?>"><?php echo $stammform; ?></textarea>
                            <span class="invalid-feedback"><?php echo $stammform_err;?></span>
                        </div>
                        <div class="form-group">
                            <label>Wortart</label>
                            <input type="text" name="art" class="form-control <?php echo (!empty($art_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $art; ?>">
                            <span class="invalid-feedback"><?php echo $art_err;?></span>
                        </div>

                        <div class="form-group">
                            <label>lexion</label>
                            <input type="text" name="flexion" class="form-control <?php echo (!empty($flexion_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $flexion; ?>">
                            <span class="invalid-feedback"><?php echo $flexion_err;?></span>
                        </div>
                        <div class="form-group">
                            <label>Übersetzung</label>
                            <input type="text" name="uebersetzung" class="form-control <?php echo (!empty($uebersetzung_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $uebersetzung; ?>">
                            <span class="invalid-feedback"><?php echo $uebersetzung_err;?></span>
                        </div>
                        <div class="form-group">
                            <label>Lektion</label>
                            <input type="text" name="lektion" class="form-control <?php echo (!empty($lektion_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $lektion; ?>">
                            <span class="invalid-feedback"><?php echo $lektion_err;?></span>
                        </div>
                        <div class="form-group">
                            <label>Tipp</label>
                            <input type="text" name="kommentar" class="form-control <?php echo (!empty($kommentar_err)) ? 'is-invalid' : ''; ?>" value="<?php echo $kommentar; ?>">
                            <span class="invalid-feedback"><?php echo $kommentar_err;?></span>
                        </div>
                        <input type="hidden" name="id" value="<?php echo $id; ?>"/>
                        <input type="submit" class="btn btn-primary" value="Submit">
                        <a href="index.php" class="btn btn-secondary ml-2">Cancel</a>
                    </form>
                </div>
            </div>        
        </div>
    </div>
</body>
</html>