diff --git a/prijs-per-postcode.php b/prijs-per-postcode.php
index 583c661..6a08d0f 100644
--- a/prijs-per-postcode.php
+++ b/prijs-per-postcode.php
@@ -1,5 +1,6 @@
 <?php
 
+session_start();
 require_once "session_dialog.php";
 /*
  * Plugin Name: Prijs per Postcode
@@ -26,6 +27,34 @@ class PrijsPerPostcode
     {
         $uri = $_SERVER["REQUEST_URI"];
         if_needed_place_postcode_form($uri);
+
+        add_action("wp_footer", "set_checkout_fields_with_javascript");
+        function set_checkout_fields_with_javascript()
+        {
+            // Only run on the checkout page
+            if (!is_checkout() || is_wc_endpoint_url()) {
+                return;
+            }
+
+            // Define the values you want to set
+            $woonplaats = $SESSION["woonplaats"];
+            $postcode = $_SESSION["postcode"];
+            $address_1 =
+                $_SESSION["straatnaam"] . " " . $_SESSION["huisnummer"];
+            // Output the JavaScript
+            ?>
+            <script type="text/javascript">
+            jQuery(document).ready(function($){
+                // Set the values for the checkout fields
+                $('#billing_city').val('<?php echo esc_js($woonplaats); ?>');
+                $('#billing_postcode').val('<?php echo esc_js($postcode); ?>');
+                $('#billing_address_1').val('<?php echo esc_js(
+                    $address_1,
+                ); ?>');
+            });
+            </script>
+            <?php
+        }
     }
 }
 
diff --git a/session_dialog.php b/session_dialog.php
index ad7ec0a..fa5beb1 100644
--- a/session_dialog.php
+++ b/session_dialog.php
@@ -3,7 +3,11 @@
 session_start();
 function if_needed_place_postcode_form($uri)
 {
-    if (strpos($uri, "/shop") !== false || strpos($uri, "/winkel") !== false) {
+    if (
+        strpos($uri, "/shop") !== false ||
+        strpos($uri, "/winkel") !== false ||
+        strpos($uri, "/product") !== false
+    ) {
         render_dialog_html();
         add_action("wp_enqueue_scripts", "modal_styles");
         add_action("wp_footer", "send_postcode_data");
@@ -24,7 +28,6 @@ function modal_styles()
 function show_modal()
 {
     ?>
-        <h1>sdfsdfsdfsdfsdfsdfsdf</h1>
         <script>
           const postcodeModal = document.querySelector("#postcode_modal");
           postcodeModal.showModal();
@@ -83,21 +86,28 @@ function render_dialog_html()
     <dialog id="postcode_modal" class="postcode_modal" closedby="none">
         <h2>Vul je postcode en huisnummer in.</h2>
         <form id="postcode_modal_form" method="post" action="">
-            <input type="text" name="postcode"
-               title="Voer een geldige Nederlandse postcode in (bijv. 1234AB of 1234 AB)."
-               pattern="[1-9][0-9]{3} ?(?!sa|sd|ss)[a-zA-Z]{2}"
-               placeholder= "1010 AA"
-               required
-            />
+            <div class="form_fields">
+                <div>
+                    <input type="text" name="postcode"
+                        title="Voer een geldige Nederlandse postcode in (bijv. 1234AB of 1234 AB)."
+                        pattern="[1-9][0-9]{3} ?(?!sa|sd|ss)[a-zA-Z]{2}"
+                        placeholder= "1010 AA"
+                        size="10"
+                        required
+                    />
 
-            <input type="text" name="huisnummer"
-                pattern="\d+([-\s]?[a-zA-Z]+)?"
-                title="Voer een geldig huisnummer in (bijv. 1, 1A, 1-A, 1a)."
-                placeholder= "12a"
-                required
-            />
-            <button id="postcode_modal_submit" type="submit">verzend</button>
+                    <input type="text" name="huisnummer"
+                        pattern="\d+([-\s]?[a-zA-Z]+)?"
+                        title="Voer een geldig huisnummer in (bijv. 1, 1A, 1-A, 1a)."
+                        placeholder= "12a"
+                        size="5"
+                        required
+                    />
+                </div>
+                <button id="postcode_modal_submit" type="submit">verzend</button>
+            </div>
         <form>
+        <div class="error_message" id="error_message"></div>
     </dialog>
     <?php
 }
@@ -121,7 +131,7 @@ function handle_postcode_modal($data)
                 "status" => "error",
                 "message" => "postcode",
             ];
-            echo $resp;
+            echo json_encode($resp);
             exit();
         }
 
@@ -130,16 +140,40 @@ function handle_postcode_modal($data)
                 "status" => "error",
                 "message" => "huisnummer",
             ];
-            echo $resp;
+            echo json_encode($resp);
+            exit();
+        }
+
+        $result = getStraatnaam($params["postcode"], $params["huisnummer"]);
+        if (isset($result["error"])) {
+            $resp = [
+                "status" => "error",
+                "message" => $result["error"],
+                "apirequest" => "openpostcode.nl",
+            ];
+            echo json_encode($resp);
             exit();
         }
 
         $_SESSION["postcode"] = $params["postcode"];
         $_SESSION["huisnummer"] = $params["huisnummer"];
+        $_SESSION["straatnaam"] = $result["straatnaam"];
+        $_SESSION["woonplaats"] = $result["woonplaats"];
+        $_SESSION["lokaak_tarief"] = postcode_in_range(
+            $params["postcode"],
+            5000,
+            5800,
+        );
 
         $resp = [
             "status" => "success",
             "message" => "all good",
+            "straatnaam" => $result["straatnaam"],
+            "lokaal_trarief" => postcode_in_range(
+                $params["postcode"],
+                5000,
+                5800,
+            ),
         ];
     } else {
         $resp = [
@@ -175,31 +209,53 @@ function verify_huisnummer($huisnummer)
     return true;
 }
 
-function check_data_at_openpostcode($oostcode, $huisnummer)
+function getStraatnaam($postcode, $huisnummer)
 {
-    $urk =
-        "https//openpostcode.nl/api/v2/address?postcode=" .
-        $postcode .
-        "&" .
-        $huisnummer;
-    $options = [
-        "http" => [
-            "method" => "GET",
-            "header" => "Accept: application/json\r\n",
-        ],
-        "ssl" => [
-            "verify_peer" => true,
-            "verify_peer_name" => true,
-        ],
-    ];
+    $url =
+        "https://openpostcode.nl/api/v2/address?postcode=" .
+        urlencode($postcode) .
+        "&huisnummer=" .
+        urlencode($huisnummer);
 
-    $context = stream_context_create($options);
-    $response = file_get_contents($url, false, $context);
+    $ch = curl_init();
+    curl_setopt($ch, CURLOPT_URL, $url);
+    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
+    curl_setopt($ch, CURLOPT_TIMEOUT, 10);
+    curl_setopt($ch, CURLOPT_USERAGENT, "PHP/OpenPostcodeClient");
 
-    if ($response === false) {
-        // Handle error
-    } else {
-        $data = json_decode($response, true);
+    $response = curl_exec($ch);
+
+    if (curl_error($ch)) {
+        curl_close($ch);
+        return ["error" => "cURL error: " . curl_error($ch)];
     }
-    return data;
+
+    curl_close($ch);
+
+    $data = json_decode($response, true);
+
+    if (isset($data["error"])) {
+        return [
+            "error" => $data["error"]["message"],
+            "code" => $data["error"]["code"],
+        ];
+    }
+
+    return [
+        "straatnaam" => $data["results"][0]["straat"],
+        "woonplaats" => $data["results"][0]["woonplaats"],
+    ];
+}
+
+function postcode_in_range($postcode, $start, $end)
+{
+    $cleanPostcode = strtoupper(preg_replace("/\s+/", "", $postcode));
+
+    if (!preg_match('/^\d{4}[A-Z]{2}$/', $cleanPostcode)) {
+        return false;
+    }
+
+    $numberPart = (int) substr($cleanPostcode, 0, 4);
+
+    return $numberPart >= $start && $numberPart <= $end;
 }