feat: 在綫聊天新增facebook洽談外掛程式 closed #918

feat: 添加artalk評論 closed #933
fix: 修復 開啟 archor 後， facebook評論加載不正確的 bug
fix: 修復 facebook 評論數無法加載的 bug

layout/includes/third-party/chat/index.pug

@@ -7,4 +7,6 @@ else if theme.daovoice && theme.daovoice.enable
 else if theme.gitter && theme.gitter.enable
   include ./gitter.pug
 else if theme.crisp && theme.crisp.enable
-  include ./crisp.pug
+  include ./crisp.pug
+else if theme.messenger && theme.messenger.enable
+  include ./messenger.pug

layout/includes/third-party/chat/messenger.pug

@@ -0,0 +1,42 @@
+- let { pageID, lang } = theme.messenger
+- lang = theme.comments.use && theme.comments.use.includes('Facebook Comments') ? theme.facebook_comments.lang : lang
+
+#fb-customer-chat.fb-customerchat(page_id=pageID attribution='biz_inbox')
+
+script.
+  document.getElementById('fb-root') ? '' : document.body.insertAdjacentHTML('afterend', '<div id="fb-root"></div>')
+
+  window.fbAsyncInit = function() {
+    FB.init({
+      xfbml: true,
+      version: 'v14.0'
+    });
+  };
+
+  (function(d, s, id) {
+    var js, fjs = d.getElementsByTagName(s)[0];
+    if (d.getElementById(id)) return;
+    js = d.createElement(s); js.id = id;
+    js.src = 'https://connect.facebook.net/!{lang}/sdk/xfbml.customerchat.js';
+    fjs.parentNode.insertBefore(js, fjs);
+  }(document, 'script', 'facebook-jssdk'));
+
+  if (!{theme.chat_btn}) {
+    var chatBtnFn = () => {
+      var chatBtn = document.getElementById("chat_btn")
+      chatBtn.addEventListener("click", function(){
+        FB.CustomerChat.show();
+      });
+    }
+    chatBtnFn()
+  } else {
+    if (!{theme.chat_hide_show}) {
+      function chatBtnHide () {
+        FB.CustomerChat.hide()
+      }
+      function chatBtnShow () {
+        FB.CustomerChat.show(false)
+      }
+    }
+  }
+