再次修复

admin/customer_service.php

@@ -203,6 +203,8 @@ ob_start();
 let selectedUser = null;
 let selectedIp = null;
 let lastMsgId = 0;
+let lastChatIds = new Set();
+let currentUserContext = '';
 
 async function refreshUsers() {
     const r = await fetch('/api/chat.php?action=admin_get_all');
@@ -301,50 +303,73 @@ async function deleteUser() {
 
 async function fetchMessages() {
     if (!selectedIp && !selectedUser) return;
-    const r = await fetch(`/api/chat.php?action=get_messages&user_id=${selectedUser}&ip=${selectedIp}`);
+    try {
-    const msgs = await r.json();
+        const r = await fetch(`/api/chat.php?action=get_messages&user_id=${selectedUser}&ip=${selectedIp}`);
-    const area = document.getElementById('messages-area');
+        const msgs = await r.json();
+        if (!msgs || !Array.isArray(msgs)) return;
 
-    // For registered users, we show all their messages. For guests, we filter by IP.
+        // If user changed, clear everything
-    const filtered = msgs.filter(m => {
+        const context = selectedUser + '_' + selectedIp;
-        if (selectedUser != 0) {
+        if (currentUserContext !== context) {
-            return m.user_id == selectedUser;
+            document.getElementById('messages-area').innerHTML = '';
-        } else {
+            lastChatIds.clear();
-            return m.ip_address === selectedIp && m.user_id == 0;
+            currentUserContext = context;
         }
-    });
 
-    if (filtered.length > 0) {
+        const area = document.getElementById('messages-area');
-        const isAtBottom = area.scrollTop + area.clientHeight >= area.scrollHeight - 50;
+        let hasNew = false;
         
-        let html = '';
+        msgs.forEach(m => {
-        filtered.forEach(m => {
+            if (!lastChatIds.has(m.id)) {
-            const msgDate = new Date(m.created_at.replace(/-/g, "/"));
+                appendMessageHTML(m);
-            const timeStr = msgDate.toLocaleTimeString('zh-CN', {hour: '2-digit', minute:'2-digit', second: '2-digit'});
+                lastChatIds.add(m.id);
-            const recallHtml = m.sender === 'admin' ? `<span class="recall-btn text-white-50" onclick="recallMessage(${m.id})">撤回</span>` : '';
+                hasNew = true;
-            const isImage = m.message.indexOf('<img') !== -1;
+            }
-            
-            html += `
-                <div class="msg ${m.sender === 'admin' ? 'msg-admin' : 'msg-user'}" style="${isImage ? 'padding: 5px; background: ' + (m.sender === 'admin' ? '#007bff' : '#f0f0f0') + ';' : ''}">
-                    <div class="msg-content">${m.message}</div>
-                    <div class="msg-time" style="${isImage ? 'position: absolute; bottom: 4px; right: 10px; background: rgba(0,0,0,0.3); color: #fff; padding: 0 4px; border-radius: 4px;' : ''}">${timeStr} ${recallHtml}</div>
-                </div>
-            `;
         });
         
-        if (area.innerHTML !== html) {
+        if (hasNew) {
-            area.innerHTML = html;
+            area.scrollTop = area.scrollHeight;
-            if (isAtBottom || lastMsgId === 0) {
+        }
-                area.scrollTop = area.scrollHeight;
+        
+        if (msgs.length > 0) {
+            const lastMsg = msgs[msgs.length - 1];
+            if (lastMsg.created_at) {
+                document.getElementById('info-time').innerText = new Date(lastMsg.created_at.replace(/-/g, "/")).toLocaleString('zh-CN');
             }
         }
-        lastMsgId = filtered.length;
+    } catch (err) {
-        
+        console.error('Fetch messages error:', err);
-        const lastMsg = filtered[filtered.length - 1];
-        document.getElementById('info-time').innerText = new Date(lastMsg.created_at.replace(/-/g, "/")).toLocaleString('zh-CN');
     }
 }
 
+function appendMessageHTML(m) {
+    const area = document.getElementById('messages-area');
+    if (!area || area.querySelector(`[data-id="${m.id}"]`)) return;
+
+    const time = m.created_at || new Date().toISOString();
+    const msgDate = time.includes('-') ? new Date(time.replace(/-/g, "/")) : new Date(time);
+    const timeStr = msgDate.toLocaleTimeString('zh-CN', {hour: '2-digit', minute:'2-digit', second: '2-digit'});
+    const recallHtml = m.sender === 'admin' ? `<span class="recall-btn text-white-50 ms-2" style="cursor:pointer; text-decoration:underline;" onclick="recallMessage(${m.id})">撤回</span>` : '';
+    const isImage = typeof m.message === 'string' && m.message.indexOf('<img') !== -1;
+    
+    const div = document.createElement('div');
+    div.className = `msg ${m.sender === 'admin' ? 'msg-admin' : 'msg-user'}`;
+    div.setAttribute('data-id', m.id);
+    
+    if (isImage) {
+        div.style.padding = '5px';
+        div.style.background = m.sender === 'admin' ? '#007bff' : '#f0f0f0';
+        div.style.lineHeight = '0';
+    }
+
+    div.innerHTML = `
+        <div class="msg-content">${m.message}</div>
+        <div class="msg-time" style="${isImage ? 'position: absolute; bottom: 8px; right: 10px; background: rgba(0,0,0,0.4); color: #fff; padding: 0 6px; border-radius: 4px; font-size: 9px; line-height: 1.5;' : ''}">${timeStr} ${recallHtml}</div>
+    `;
+    
+    area.appendChild(div);
+}
+
 document.getElementById('plus-btn').addEventListener('click', () => {
     document.getElementById('image-input').click();
 });
@@ -353,22 +378,50 @@ document.getElementById('image-input').addEventListener('change', async (e) => {
     const file = e.target.files[0];
     if (!file) return;
 
+    // Local preview for "0 latency"
+    const localUrl = URL.createObjectURL(file);
+    const tempId = 'temp_img_' + Date.now();
+    const localMsgHtml = `<img src="${localUrl}" class="img-fluid rounded" style="max-width: 100%; max-height: 250px; object-fit: contain; margin: 5px 0; opacity: 0.6;">`;
+    
+    appendMessageHTML({
+        id: tempId,
+        sender: 'admin',
+        message: localMsgHtml,
+        created_at: new Date().toISOString()
+    });
+    const area = document.getElementById('messages-area');
+    area.scrollTop = area.scrollHeight;
+
     const formData = new FormData();
     formData.append('file', file);
-    formData.append('user_id', selectedUser);
+    formData.append('user_id', selectedUser || 0);
-    formData.append('ip_address', selectedIp);
+    formData.append('ip_address', selectedIp || '');
 
-    const r = await fetch('/api/chat.php?action=upload_image', {
+    try {
-        method: 'POST',
+        const r = await fetch('/api/chat.php?action=upload_image', {
-        body: formData
+            method: 'POST',
-    });
+            body: formData
-    const res = await r.json();
+        });
-    if (res.success) {
+        const res = await r.json();
-        fetchMessages();
+        
-    } else {
+        // Remove temp
-        alert('上传失败: ' + res.error);
+        const tempMsg = document.querySelector(`[data-id="${tempId}"]`);
+        if (tempMsg) tempMsg.remove();
+
+        if (res.success && res.message) {
+            appendMessageHTML(res.message);
+            area.scrollTop = area.scrollHeight;
+            fetchMessages();
+        } else {
+            alert('上传失败: ' + res.error);
+        }
+    } catch(err) {
+        const tempMsg = document.querySelector(`[data-id="${tempId}"]`);
+        if (tempMsg) tempMsg.remove();
     }
+    
     e.target.value = ''; // Reset
+    setTimeout(() => URL.revokeObjectURL(localUrl), 5000);
 });
 
 document.getElementById('chat-form').addEventListener('submit', async (e) => {
@@ -377,14 +430,37 @@ document.getElementById('chat-form').addEventListener('submit', async (e) => {
     const msg = input.value.trim();
     if (!msg) return;
 
+    input.value = '';
+    
+    // Optimistic UI
+    const tempId = 'temp_msg_' + Date.now();
+    appendMessageHTML({
+        id: tempId,
+        sender: 'admin',
+        message: msg,
+        created_at: new Date().toISOString()
+    });
+    const area = document.getElementById('messages-area');
+    area.scrollTop = area.scrollHeight;
+
     const fd = new URLSearchParams();
     fd.append('message', msg);
     fd.append('user_id', selectedUser);
     fd.append('ip_address', selectedIp);
 
-    await fetch('/api/chat.php?action=admin_send', { method: 'POST', body: fd });
+    try {
-    input.value = '';
+        const r = await fetch('/api/chat.php?action=admin_send', { method: 'POST', body: fd });
-    fetchMessages();
+        const res = await r.json();
+        
+        const tempMsg = document.querySelector(`[data-id="${tempId}"]`);
+        if (tempMsg) tempMsg.remove();
+
+        if (res.success && res.message) {
+            appendMessageHTML(res.message);
+            area.scrollTop = area.scrollHeight;
+            fetchMessages();
+        }
+    } catch(err) {}
 });
 
 document.getElementById('save-remark-btn').addEventListener('click', async () => {

admin/layout.php

@@ -5,7 +5,7 @@ if (session_status() === PHP_SESSION_NONE) session_start();
 
 // Force simplified Chinese for admin
 $lang = 'zh';
-$_SESSION['lang'] = 'zh';
+// $_SESSION['lang'] = 'zh'; // Do not persist to session to avoid affecting front-end default language
 
 // Admin check
 $admin = null;

admin/login.php

@@ -1,6 +1,7 @@
 <?php
 require_once __DIR__ . '/../db/config.php';
 require_once __DIR__ . '/../includes/lang.php';
+$lang = 'zh'; // Force Simplified Chinese for admin login
 
 if (session_status() === PHP_SESSION_NONE) session_start();
 

api/chat.php

@@ -28,24 +28,35 @@ if ($action === 'upload_image' || (isset($_POST['action']) && $_POST['action'] =
     $targetPath = $targetDir . $filename;
     if (move_uploaded_file($file['tmp_name'], $targetPath)) {
         $imageUrl = '/assets/images/chat/' . $filename;
-        
         $message = '<img src="' . $imageUrl . '" class="img-fluid rounded cursor-pointer" style="max-width: 100%; max-height: 250px; object-fit: contain; margin: 5px 0;" onclick="window.open(\'' . $imageUrl . '\')">';
         
         if (isset($_SESSION['admin_id'])) {
-            $user_id = $_POST['user_id'] ?? 0;
+            $user_id = (int)($_POST['user_id'] ?? 0);
             $ip = $_POST['ip_address'] ?? '';
             $sender = 'admin';
             $admin_id = $_SESSION['admin_id'];
             $stmt = db()->prepare("INSERT INTO messages (user_id, admin_id, sender, message, ip_address) VALUES (?, ?, ?, ?, ?)");
             $stmt->execute([$user_id, $admin_id, $sender, $message, $ip]);
         } else {
-            $user_id = $_SESSION['user_id'] ?? 0;
+            $user_id = (int)($_SESSION['user_id'] ?? 0);
             $ip = getRealIP();
+            $sender = 'user';
             $stmt = db()->prepare("INSERT INTO messages (user_id, sender, message, ip_address) VALUES (?, ?, ?, ?)");
-            $stmt->execute([$user_id, 'user', $message, $ip]);
+            $stmt->execute([$user_id, $sender, $message, $ip]);
         }
         
-        echo json_encode(['success' => true, 'url' => $imageUrl]);
+        $newId = db()->lastInsertId();
+        $createdAt = date('Y-m-d H:i:s');
+        echo json_encode([
+            'success' => true, 
+            'url' => $imageUrl, 
+            'message' => [
+                'id' => $newId, 
+                'sender' => $sender, 
+                'message' => $message, 
+                'created_at' => $createdAt
+            ]
+        ]);
     } else {
         echo json_encode(['success' => false, 'error' => 'Failed to move uploaded file']);
     }
@@ -76,19 +87,19 @@ if ($action === 'send_message') {
     $message = $_POST['message'] ?? '';
     if (!$message) exit(json_encode(['success' => false]));
 
-    $user_id = $_SESSION['user_id'] ?? 0;
+    $user_id = (int)($_SESSION['user_id'] ?? 0);
     $ip = getRealIP();
 
     $stmt = db()->prepare("INSERT INTO messages (user_id, sender, message, ip_address) VALUES (?, ?, ?, ?)");
     $stmt->execute([$user_id, 'user', $message, $ip]);
     $newId = db()->lastInsertId();
-    echo json_encode(['success' => true, 'id' => $newId]);
+    echo json_encode(['success' => true, 'id' => $newId, 'message' => ['id' => $newId, 'sender' => 'user', 'message' => $message, 'created_at' => date('Y-m-d H:i:s')]]);
     exit;
 }
 
 if ($action === 'admin_send') {
     $message = $_POST['message'] ?? '';
-    $user_id = $_POST['user_id'] ?? 0;
+    $user_id = (int)($_POST['user_id'] ?? 0);
     $target_ip = $_POST['ip_address'] ?? '';
     
     if (!$message) exit(json_encode(['success' => false]));
@@ -99,10 +110,11 @@ if ($action === 'admin_send') {
     $stmt = db()->prepare("INSERT INTO messages (user_id, admin_id, sender, message, ip_address) VALUES (?, ?, ?, ?, ?)");
     $stmt->execute([$user_id, $admin_id, $sender, $message, $target_ip]);
     $newId = db()->lastInsertId();
-    echo json_encode(['success' => true, 'id' => $newId]);
+    echo json_encode(['success' => true, 'id' => $newId, 'message' => ['id' => $newId, 'sender' => $sender, 'message' => $message, 'created_at' => date('Y-m-d H:i:s')]]);
     exit;
 }
 
+
 if ($action === 'ping') {
     $user_id = $_SESSION['user_id'] ?? 0;
     $ip = getRealIP();
@@ -118,7 +130,7 @@ if ($action === 'admin_get_all') {
         SELECT 
             v.user_id, 
             v.ip_address, 
-            CASE WHEN m.message LIKE '<img%' THEN '[图片]' ELSE COALESCE(m.message, '用户已进入聊天室') END as message, 
+            CASE WHEN m.message LIKE '<img%' THEN '[Image]' ELSE COALESCE(m.message, 'User joined') END as message, 
             COALESCE(m.created_at, v.last_activity) as created_at,
             CASE WHEN u.email LIKE '%@user.byro' THEN u.username ELSE COALESCE(u.email, u.username) END as username, 
             u.uid, 
@@ -131,20 +143,20 @@ if ($action === 'admin_get_all') {
                 MAX(last_activity) as last_activity,
                 MAX(user_time) as user_time
             FROM (
-                SELECT user_id, ip_address, MAX(created_at) as last_activity, NULL as user_time FROM messages GROUP BY user_id, ip_address
+                SELECT COALESCE(user_id, 0) as user_id, ip_address, MAX(created_at) as last_activity, NULL as user_time FROM messages GROUP BY COALESCE(user_id, 0), ip_address
                 UNION
-                SELECT user_id, ip_address, MAX(last_ping) as last_activity, MAX(user_time) as user_time FROM chat_visitors GROUP BY user_id, ip_address
+                SELECT COALESCE(user_id, 0) as user_id, ip_address, MAX(last_ping) as last_activity, MAX(user_time) as user_time FROM chat_visitors GROUP BY COALESCE(user_id, 0), ip_address
             ) t1
             GROUP BY user_id, (CASE WHEN user_id = 0 THEN ip_address ELSE '0' END)
         ) v
         LEFT JOIN (
             SELECT m1.* FROM messages m1
             INNER JOIN (
-                SELECT MAX(id) as max_id FROM messages GROUP BY user_id, (CASE WHEN user_id = 0 THEN ip_address ELSE '0' END)
+                SELECT MAX(id) as max_id FROM messages GROUP BY COALESCE(user_id, 0), (CASE WHEN COALESCE(user_id, 0) = 0 THEN ip_address ELSE '0' END)
             ) m2 ON m1.id = m2.max_id
-        ) m ON (v.user_id = m.user_id AND (v.user_id != 0 OR v.ip_address = m.ip_address))
+        ) m ON (v.user_id = COALESCE(m.user_id, 0) AND (v.user_id != 0 OR v.ip_address = m.ip_address))
         LEFT JOIN users u ON (v.user_id = u.id AND v.user_id != 0)
-        LEFT JOIN chat_remarks r ON (v.user_id = r.user_id AND (v.user_id != 0 OR v.ip_address = r.ip_address))
+        LEFT JOIN chat_remarks r ON (v.user_id = COALESCE(r.user_id, 0) AND (v.user_id != 0 OR v.ip_address = r.ip_address))
         WHERE v.last_activity > DATE_SUB(NOW(), INTERVAL 48 HOUR)
         ORDER BY created_at DESC
     ");

certificate.php

@@ -36,7 +36,7 @@ $site_certificate = getSetting('site_certificate', '');
                             </div>
                             <div class="mt-3">
                                 <button class="btn btn-primary btn-sm rounded-pill px-3" onclick="window.open('<?= htmlspecialchars($cert) ?>', '_blank')">
-                                    <i class="bi bi-zoom-in me-2"></i>查看高清原图
+                                    <i class="bi bi-zoom-in me-2"></i><?= __('view_full_image') ?>
                                 </button>
                             </div>
                         </div>

db/config.php

@@ -1,5 +1,6 @@
 <?php
 // Generated by setup_mariadb_project.sh — edit as needed.
+// Baota / Local Deployment Settings - Change these to match your database
 define('DB_HOST', '127.0.0.1');
 define('DB_NAME', 'app_38451');
 define('DB_USER', 'app_38451');

db/database.sql

@@ -1,3 +1,9 @@
+/*
+BYRO Digital Asset Platform - Full Database Dump
+Date: 2026-02-20
+Instructions: Import this file into your MySQL/MariaDB database.
+*/
+
 /*M!999999\- enable the sandbox mode */ 
 -- MariaDB dump 10.19  Distrib 10.11.14-MariaDB, for debian-linux-gnu (x86_64)
 --

includes/footer.php

@@ -225,43 +225,69 @@ csUploadBtn.addEventListener('click', () => csFileInput.click());
 csFileInput.addEventListener('change', async () => {
     if (!csFileInput.files[0]) return;
     const file = csFileInput.files[0];
+    
+    // Create local preview for "0 latency"
+    const localUrl = URL.createObjectURL(file);
+    const tempId = 'temp_img_' + Date.now();
+    const localMsgHtml = `<img src="${localUrl}" class="img-fluid rounded" style="max-width: 100%; max-height: 250px; object-fit: contain; margin: 5px 0; opacity: 0.6;">`;
+    
+    appendMessageHTML({
+        id: tempId,
+        sender: 'user',
+        message: localMsgHtml,
+        created_at: new Date().toISOString()
+    });
+    scrollToBottom();
+
     const formData = new FormData();
     formData.append('file', file);
     formData.append('action', 'upload_image');
 
-    appendMessage('user', '<i class="bi bi-image"></i> <?= __("uploading") ?>');
-
     try {
         const resp = await fetch('/api/chat.php', {
             method: 'POST',
             body: formData
         });
         const data = await resp.json();
-        if (data.success) {
+        
+        // Remove local preview
+        const tempMsg = document.querySelector(`[data-id="${tempId}"]`);
+        if (tempMsg) tempMsg.remove();
+
+        if (data.success && data.message) {
+            appendMessageHTML(data.message);
+            scrollToBottom();
             pollMessages();
         } else {
             alert(data.error || '<?= __("send_failed") ?>');
         }
     } catch (err) {
         console.error('Upload error:', err);
+        const tempMsg = document.querySelector(`[data-id="${tempId}"]`);
+        if (tempMsg) tempMsg.remove();
     }
     csFileInput.value = '';
+    // Clean up object URL
+    setTimeout(() => URL.revokeObjectURL(localUrl), 5000);
 });
 
 csToggle.addEventListener('click', () => {
     csBox.classList.toggle('d-none');
-    scrollToBottom();
     if (!csBox.classList.contains('d-none')) {
         const now = new Date();
         const timeStr = now.toLocaleTimeString('zh-CN', {hour: '2-digit', minute:'2-digit', second: '2-digit'});
         fetch('/api/chat.php?action=ping&user_time=' + encodeURIComponent(timeStr));
+        scrollToBottom();
+        pollMessages();
     }
 });
 
 csClose.addEventListener('click', () => csBox.classList.add('d-none'));
 
 function scrollToBottom() {
-    csMessages.scrollTop = csMessages.scrollHeight;
+    setTimeout(() => {
+        csMessages.scrollTop = csMessages.scrollHeight;
+    }, 50);
 }
 
 csForm.addEventListener('submit', async (e) => {
@@ -271,6 +297,16 @@ csForm.addEventListener('submit', async (e) => {
 
     csInput.value = '';
     
+    // Optimistic UI update
+    const tempId = 'temp_msg_' + Date.now();
+    appendMessageHTML({
+        id: tempId,
+        sender: 'user',
+        message: msg,
+        created_at: new Date().toISOString()
+    });
+    scrollToBottom();
+
     try {
         const resp = await fetch('/api/chat.php?action=send_message', {
             method: 'POST',
@@ -278,7 +314,14 @@ csForm.addEventListener('submit', async (e) => {
             body: `message=${encodeURIComponent(msg)}`
         });
         const data = await resp.json();
+        
+        // Remove temp message and wait for poll to bring the real one
+        const tempMsg = document.querySelector(`[data-id="${tempId}"]`);
+        if (tempMsg) tempMsg.remove();
+        
         if (data.success) {
+            appendMessageHTML(data.message);
+            scrollToBottom();
             pollMessages();
         }
     } catch (err) {
@@ -286,38 +329,43 @@ csForm.addEventListener('submit', async (e) => {
     }
 });
 
-function appendMessage(sender, text, time = null) {
+function appendMessageHTML(m) {
-    const div = document.createElement('div');
+    if (document.querySelector(`[data-id="${m.id}"]`)) return;
-    div.className = `mb-3 d-flex flex-column ${sender === 'user' ? 'align-items-end' : 'align-items-start'}`;
+
+    const sender = m.sender;
+    const text = m.message;
+    const time = m.created_at;
+    const isImage = text.indexOf('<img') !== -1;
     
     let dateObj;
-    if (time) {
+    if (typeof time === 'string' && time.includes('-')) {
         dateObj = new Date(time.replace(/-/g, "/"));
     } else {
-        dateObj = new Date();
+        dateObj = new Date(time);
     }
     const timeStr = dateObj.toLocaleTimeString('zh-CN', {hour: '2-digit', minute:'2-digit', second: '2-digit'});
 
-    div.innerHTML = `
+    const msgHtml = `
-        <div class="p-2 px-3 rounded-4 small ${sender === 'user' ? 'bg-primary text-white' : 'bg-dark text-white border border-secondary'}" style="max-width: 80%; color: #ffffff !important; word-break: break-all; position: relative; padding-bottom: 20px !important;">
+        <div class="mb-3 d-flex flex-column ${sender === 'user' ? 'align-items-end' : 'align-items-start'} message-item" data-id="${m.id}">
-            ${text}
+            <div class="p-2 px-3 rounded-4 small ${sender === 'user' ? 'bg-primary text-white' : 'bg-dark text-white border border-secondary'}" style="max-width: 80%; color: #ffffff !important; word-break: break-all; position: relative; padding-bottom: 20px !important; ${isImage ? 'padding: 5px !important; padding-bottom: 5px !important; line-height: 0;' : ''}">
-            <div style="font-size: 9px; opacity: 0.6; position: absolute; bottom: 4px; ${sender === 'user' ? 'right: 10px;' : 'left: 10px;'}">${timeStr}</div>
+                ${text}
+                <div style="font-size: 9px; opacity: 0.6; position: absolute; bottom: 4px; ${sender === 'user' ? 'right: 10px;' : 'left: 10px;'} ${isImage ? 'background: rgba(0,0,0,0.4); padding: 0 4px; border-radius: 4px; bottom: 8px;' : ''}">${timeStr}</div>
+            </div>
         </div>
     `;
-    csMessages.appendChild(div);
+    
-    scrollToBottom();
+    csMessages.insertAdjacentHTML('beforeend', msgHtml);
 }
 
 // Polling for new messages
-let lastMsgId = 0;
+let lastChatIds = new Set();
-let lastPingTime = 0;
-let lastChatHtml = '';
 
 async function pollMessages() {
     if (csBox.classList.contains('d-none')) return;
     
     // Ping every 10 seconds to update user time
     const now = Date.now();
+    if (typeof lastPingTime === 'undefined') window.lastPingTime = 0;
     if (now - lastPingTime > 10000) {
         const timeStr = new Date().toLocaleTimeString('zh-CN', {hour: '2-digit', minute:'2-digit', second: '2-digit'});
         fetch('/api/chat.php?action=ping&user_time=' + encodeURIComponent(timeStr));
@@ -327,37 +375,23 @@ async function pollMessages() {
     try {
         const resp = await fetch('/api/chat.php?action=get_messages');
         const data = await resp.json();
-        if (data) {
+        if (data && Array.isArray(data)) {
-            let html = '<div class="text-center text-muted small mb-3"><?= __("welcome_support") ?></div>';
+            let hasNew = false;
             data.forEach(m => {
-                const sender = m.sender;
+                if (!lastChatIds.has(m.id)) {
-                const text = m.message;
+                    appendMessageHTML(m);
-                const time = m.created_at;
+                    lastChatIds.add(m.id);
-                const isImage = text.indexOf('<img') !== -1;
+                    hasNew = true;
-                
+                }
-                let dateObj = new Date(time.replace(/-/g, "/"));
-                const timeStr = dateObj.toLocaleTimeString('zh-CN', {hour: '2-digit', minute:'2-digit', second: '2-digit'});
-                
-                html += `
-                    <div class="mb-3 d-flex flex-column ${sender === 'user' ? 'align-items-end' : 'align-items-start'}">
-                        <div class="p-2 px-3 rounded-4 small ${sender === 'user' ? 'bg-primary text-white' : 'bg-dark text-white border border-secondary'}" style="max-width: 80%; color: #ffffff !important; word-break: break-all; position: relative; padding-bottom: 20px !important; ${isImage ? 'padding: 5px !important;' : ''}">
-                            ${text}
-                            <div style="font-size: 9px; opacity: 0.6; position: absolute; bottom: 4px; ${sender === 'user' ? 'right: 10px;' : 'left: 10px;'} ${isImage ? 'background: rgba(0,0,0,0.4); padding: 0 4px; border-radius: 4px;' : ''}">${timeStr}</div>
-                        </div>
-                    </div>
-                `;
-                if (parseInt(m.id) > lastMsgId) lastMsgId = parseInt(m.id);
             });
             
-            if (csMessages.innerHTML !== html) {
+            if (hasNew) {
-                const isAtBottom = csMessages.scrollTop + csMessages.clientHeight >= csMessages.scrollHeight - 50;
+                scrollToBottom();
-                csMessages.innerHTML = html;
-                if (isAtBottom) scrollToBottom();
             }
         }
     } catch (err) {}
 }
-setInterval(pollMessages, 300);
+setInterval(pollMessages, 300); // 300ms polling for "zero delay" feel
 </script>
 
 <style>

includes/lang.php

@@ -1,9 +1,9 @@
 <?php
 session_start();
 
-$lang = $_SESSION['lang'] ?? 'en';
+$lang = $_SESSION['lang'] ?? 'en'; // Default to English
 if (isset($_GET['lang'])) {
-    $lang = $_GET['lang'] === 'en' ? 'en' : 'zh';
+    $lang = $_GET['lang'] === 'zh' ? 'zh' : 'en';
     $_SESSION['lang'] = $lang;
 }
 
@@ -371,6 +371,7 @@ $translations = [
         'platform_certificate' => '平台注册证书',
         'no_certificate_yet' => '暂无证书',
         'trade' => '交易',
+        'view_full_image' => '查看高清原图',
         'failed' => '失败',
         'success' => '成功',
         'direction' => '方向',
@@ -891,6 +892,7 @@ $translations = [
         'platform_certificate' => 'Platform Registration Certificate',
         'no_certificate_yet' => 'No certificate available yet',
         'trade' => 'Trade',
+        'view_full_image' => 'View Full Image',
         'failed' => 'Failed',
         'success' => 'Success',
         'direction' => 'Direction',