diff --git a/TP3/js/chat.js b/TP3/js/chat.js
index 643199d..be059f7 100644
--- a/TP3/js/chat.js
+++ b/TP3/js/chat.js
@@ -67,7 +67,10 @@ function sendMessage(){
     let channelId = channelsList.options[channelsList.selectedIndex].value;
     const message = document.getElementById("message").value;
     document.getElementById("message").value = "";
-    ajaxRequest("POST", "http://serveur-ajax-s3.felix/TP3/php/chat.php?request=messages&channel_id=" + channelId + "&userlogin=etudiant0&message=" + message, getMessages, message);
+    if(message === ""){
+        return;
+    }
+    ajaxRequest("POST", "http://serveur-ajax-s3.felix/TP3/php/chat.php?request=messages", getMessages, "&channel_id=" + channelId + "&userlogin=etudiant0&message=" + message);
 }
 
 getChannels();
diff --git a/TP3/js/utils.js b/TP3/js/utils.js
index 65041dd..b41186f 100644
--- a/TP3/js/utils.js
+++ b/TP3/js/utils.js
@@ -1,9 +1,6 @@
 console.log("utils.js loaded");
 
 function ajaxRequest(type, url, callback=null, data=null){
-    console.log("ajaxRequest called");
-    console.log("type: " + type);
-    console.log("url: " + url);
     let xhr = new XMLHttpRequest();
     xhr.open(type, url, true);
     xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
@@ -11,9 +8,19 @@ function ajaxRequest(type, url, callback=null, data=null){
         switch (xhr.status){
             case 200:
             case 201:
-                let parsedResponse = JSON.parse(xhr.responseText);
-                if (callback){
-                    callback(parsedResponse);
+                if(xhr.responseText.trim() !== ''){
+                    try {
+                        let parsedResponse = JSON.parse(xhr.responseText);
+                        if (callback){
+                            callback(parsedResponse);
+                        }
+                    }
+                    catch (e){
+                        errorAlert("Erreur: " + e);
+                    }
+                }
+                else{
+                    errorAlert("Erreur: Aucune donnée reçue");
                 }
                 break;
             default:
diff --git a/TP3/php/chat.php b/TP3/php/chat.php
index 425fd67..20384da 100644
--- a/TP3/php/chat.php
+++ b/TP3/php/chat.php
@@ -22,26 +22,34 @@ if(isset($_GET['request']) && $_GET['request'] == 'channels'){
     }
 }
 
-if(isset($_GET['request']) && $_GET['request'] == 'messages' && $_GET['channel_id']){
-    $channel_id = intval($_GET['channel_id']);
-    $messages = dbGetMessages($pdo, $channel_id);
-    if($messages){
-        echo json_encode($messages);
+if(isset($_GET['request']) && $_GET['request'] == 'messages'){
+    if(isset($_GET['channel_id'])){
+        header('Content-Type: application/json');
+        $channel_id = intval($_GET['channel_id']);
+        $messages = dbGetMessages($pdo, $channel_id);
+        if($messages){
+            echo json_encode($messages);
+        }
+        else{
+            echo json_encode([]);
+        }
     }
     else{
-        echo json_encode([]);
+        if(isset($_POST['channel_id']) && $_POST['userlogin'] && $_POST['message']){
+            header('Content-Type: application/json');
+            $channel_id = intval($_POST['channel_id']);
+            $userlogin = $_POST['userlogin'];
+            $message = $_POST['message'];
+            $result = dbAddMessage($pdo, $userlogin, $channel_id, $message);
+            if($result){
+                echo json_encode(array("status" => "success", "message" => "Message added"));
+            } else {
+                echo json_encode(array("status" => "error", "message" => "Message not added"));
+            }
+        }
+        else{
+            echo json_encode(array("status" => "error", "message" => "Invalid request"));
+        }
     }
-}
 
-if(isset($_POST['request']) && $_POST['request'] == 'messages' && $_POST['channel_id'] && $_POST['userlogin'] && $_POST['message']){
-    $channel_id = intval($_POST['channel_id']);
-    $userlogin = $_POST['userlogin'];
-    $message = $_POST['message'];
-    $result = dbAddMessage($pdo, $userlogin, $channel_id, $message);
-    if($result){
-        echo json_encode('Message added');
-    }
-    else{
-        echo json_encode('Message not added');
-    }
 }
\ No newline at end of file
diff --git a/TP3/test.http b/TP3/test.http
new file mode 100644
index 0000000..943da30
--- /dev/null
+++ b/TP3/test.http
@@ -0,0 +1,5 @@
+POST http://serveur-ajax-s3.felix/TP3/php/chat.php
+
+Content-Type: application/x-www-form-urlencoded
+
+request=messages&channel_id=1&userlogin=etudient0&message=Test%20Post
\ No newline at end of file