Conditional Case Sensitivity with API Data

I am new to API integration and PHP. I recently integrated a VIN decoder into my app. Enter a vehicle's VIN into the input box, click submit, and information regarding the vehicle is returned.

I have been working on formatting the data output to my liking. Specifically the vehicle Make data. The Make data is presented in all-caps. For example, Audi is outputted as AUDI. To fix this I added the following code:

$data = array();
foreach ($json['Results'][0] as $k => $v){

  if ($k == "Make"){
    $v = strtolower($v);
    $v = ucwords($v);

  }
}

With this revision, AUDI is presented as Audi, which is great. I am running into issues with brands such as BMW and Mercedes-Benz. With this addition, they are presented as Bmw and Mercedes-benz. I have tried to add simple if statements to solve this but I have been unsuccessful.

Any ideas as to how I can create exceptions to the upper-case rule I created?

Here is my html code, a simple input box and submit button.

<!DOCTYPE html>
<html>

<head>
<title>VIN Decoder API Test</title>

<style type="text/css">
input,button {width: 200px;display: block;margin-left: auto;margin-right: auto;}
button {width: 100px;background-color: darkgray;}
</style>

</head>

<body>

    <form action="processvin4.php" method="post">

    <input type="text" id="b12" placeholder="Enter VIN" name="b12" maxlength="100"/>
    <br>
    <button id="submit_btn">Submit</button>

  </form>

  <br>
  <br>

</body>
</html>

And my php code with attempted if statements:

<?php

$vin = $_POST["b12"];

if ($vin) {
$postdata = http_build_query([
        'format' => 'json',
        'data' => $vin
    ]
);
$opts = [
    'http' => [
        'method' => 'POST',
        'content' => $postdata
    ]
];

$apiURL = "https://vpic.nhtsa.dot.gov/api/vehicles/DecodeVINValuesBatch/";
$context = stream_context_create($opts);
$fp = fopen($apiURL, 'rb', false, $context);
$line_of_text = fgets($fp);
$json = json_decode($line_of_text, true);
fclose($fp);

$data = array();
foreach ($json['Results'][0] as $k => $v){
  if ($k == "Make"){
    $v = strtolower($v);
    $v = ucwords($v);
    if ($v == "BMW"){
      $v = "BMW";
    }
    if ($v == "MERCEDES-BENZ"){
      $v = "Mercedes-Benz";
    }
  }

  if (!empty($v)) {
    $data[$k] = ($k).": ".($v);
  }
}


  echo $data['Make']. '<br />';


  }

else {
echo 'No Vin Inputted';
  }




?>

Thanks for any help!

Solution

To simply fix what you're trying, you just need to put the strtolower in an "else"

if ($k == "Make"){
  if ($v == "BMW"){
    $v = "BMW";
  }
  else if ($v == "MERCEDES-BENZ"){
    $v = "Mercedes-Benz";
  }
  else {
    $v = strtolower($v);
    $v = ucwords($v);
  }
}