Fix widget reply notification effects

public/widget.js

@@ -73,7 +73,10 @@
     const dropzone = root.querySelector(".mf-dropzone");
     const attachmentList = root.querySelector(".mf-attachment-list");
     let selectedFiles = [];
-    let unreadAdminCount = 0;
+    const messageEffectState = {
+      unreadAdminCount: 0,
+      knownAdminMessageId: 0
+    };
     renderSoundState(soundButton);
 
     launcher.addEventListener("click", () => {
@@ -81,8 +84,8 @@
       if (panel.classList.contains("open")) {
         launcher.classList.remove("mf-notify");
         clearMessageEffects(launcher);
-        unreadAdminCount = 0;
+        messageEffectState.unreadAdminCount = 0;
-        updateMessageBadge(launcher, unreadAdminCount);
+        updateMessageBadge(launcher, messageEffectState.unreadAdminCount);
         scrollMessagesToBottom(messages);
         markConversationSeen();
       }
@@ -164,8 +167,9 @@
         form.message.value = "";
         selectedFiles = [];
         renderSelectedFiles(attachmentList, selectedFiles);
-        renderConversation(messages, data);
+        handleConversationUpdate(data, messages, panel, launcher, settings, messageEffectState, { notify: false });
-        connectEvents(messages, typing, panel, launcher, settings);
+        connectEvents(messages, typing, panel, launcher, settings, messageEffectState);
+        startConversationPolling(messages, panel, launcher, settings, messageEffectState);
       } catch {
         showFormError(root, "Zpravu se nepodarilo odeslat. Zkuste to prosim znovu.");
       } finally {
@@ -184,7 +188,14 @@
       }
     });
     if (session.conversationId) {
-      loadExistingConversation(messages, panel).finally(() => connectEvents(messages, typing, panel, launcher, settings));
+      loadExistingConversation(messages, panel)
+        .then((data) => {
+          messageEffectState.knownAdminMessageId = latestAdminMessageId(data?.messages || []);
+        })
+        .finally(() => {
+          connectEvents(messages, typing, panel, launcher, settings, messageEffectState);
+          startConversationPolling(messages, panel, launcher, settings, messageEffectState);
+        });
     }
   }
 
@@ -196,7 +207,7 @@
     };
   }
 
-  function connectEvents(messages, typing, panel, launcher, settings) {
+  function connectEvents(messages, typing, panel, launcher, settings, messageEffectState) {
     if (session.events || !session.conversationId) return;
     session.events = new EventSource(`${apiBase}/api/widget/conversations/${session.conversationId}/events`);
     session.events.addEventListener("message", (event) => {
@@ -207,17 +218,17 @@
         connectEvents.typingTimer = setTimeout(() => { typing.hidden = true; }, 1800);
       }
       if (data.type === "message:new") {
-        renderConversation(messages, data.payload);
+        handleConversationUpdate(data.payload, messages, panel, launcher, settings, messageEffectState, { notify: true });
-        if (panel.classList.contains("open")) markConversationSeen();
-        const eventMessages = data.payload?.messages || [];
-        const lastMessage = eventMessages[eventMessages.length - 1];
-        if (lastMessage?.senderType === "admin" && !panel.classList.contains("open")) {
-          unreadAdminCount += 1;
-          applyAdminReplyEffects(launcher, settings, unreadAdminCount);
-          playNotifySound();
-        }
       }
     });
+    session.events.onerror = () => {
+      session.events?.close();
+      session.events = null;
+      clearTimeout(connectEvents.reconnectTimer);
+      connectEvents.reconnectTimer = setTimeout(() => {
+        connectEvents(messages, typing, panel, launcher, settings, messageEffectState);
+      }, 2500);
+    };
   }
 
   function createHeaderActions(root, closeButton) {
@@ -283,12 +294,56 @@
       const data = await fetchJson(`${apiBase}/api/widget/conversations/${session.conversationId}?visitorToken=${encodeURIComponent(session.visitorToken)}`);
       renderConversation(messages, data);
       if (panel.classList.contains("open")) markConversationSeen();
+      return data;
     } catch {
       session.conversationId = null;
       saveSession();
+      return null;
     }
   }
 
+  function startConversationPolling(messages, panel, launcher, settings, messageEffectState) {
+    if (session.pollTimer || !session.conversationId) return;
+    session.pollTimer = setInterval(async () => {
+      if (!session.conversationId) return;
+      try {
+        const data = await fetchJson(`${apiBase}/api/widget/conversations/${session.conversationId}?visitorToken=${encodeURIComponent(session.visitorToken)}`);
+        handleConversationUpdate(data, messages, panel, launcher, settings, messageEffectState, { notify: true });
+      } catch {}
+    }, 10_000);
+  }
+
+  function handleConversationUpdate(data, messages, panel, launcher, settings, messageEffectState, options = {}) {
+    if (!data?.messages) return;
+    const previousAdminMessageId = messageEffectState.knownAdminMessageId || 0;
+    const latestAdminId = latestAdminMessageId(data.messages);
+    const hasNewAdminMessage = latestAdminId > previousAdminMessageId;
+
+    renderConversation(messages, data);
+    messageEffectState.knownAdminMessageId = Math.max(previousAdminMessageId, latestAdminId);
+
+    if (panel.classList.contains("open")) {
+      markConversationSeen();
+      messageEffectState.unreadAdminCount = 0;
+      updateMessageBadge(launcher, messageEffectState.unreadAdminCount);
+      clearMessageEffects(launcher);
+      return;
+    }
+
+    if (options.notify !== false && hasNewAdminMessage) {
+      messageEffectState.unreadAdminCount += 1;
+      applyAdminReplyEffects(launcher, settings, messageEffectState.unreadAdminCount);
+      playNotifySound();
+    }
+  }
+
+  function latestAdminMessageId(messages) {
+    return messages.reduce((max, message) => {
+      if (message.senderType !== "admin") return max;
+      return Math.max(max, Number(message.id) || 0);
+    }, 0);
+  }
+
   function renderConversation(messages, data) {
     messages.innerHTML = "";
     let lastAdminName = null;

server.js

@@ -56,7 +56,10 @@ async function route(req, res) {
   if (req.method === "GET" && url.pathname === "/admin") return file(res, path.join(PUBLIC_DIR, "admin.html"), "text/html; charset=utf-8");
   if (req.method === "GET" && url.pathname === "/preview") return file(res, path.join(PUBLIC_DIR, "preview.html"), "text/html; charset=utf-8");
   if (req.method === "GET" && url.pathname.startsWith("/uploads/")) return serveUpload(res, url.pathname);
-  if (req.method === "GET" && url.pathname === "/widget.js") return file(res, path.join(PUBLIC_DIR, "widget.js"), "application/javascript; charset=utf-8");
+  if (req.method === "GET" && url.pathname === "/widget.js") {
+    res.setHeader("Cache-Control", "no-store, max-age=0");
+    return file(res, path.join(PUBLIC_DIR, "widget.js"), "application/javascript; charset=utf-8");
+  }
   if (req.method === "GET" && url.pathname.startsWith("/admin.")) return servePublic(res, url.pathname);
 
   if (url.pathname === "/api/admin/login" && req.method === "POST") return adminLogin(req, res);