[minor] reply mail button in timeline if doctype is communication

frappe/public/js/frappe/form/footer/timeline.html

@@ -13,9 +13,15 @@
         </div>
     </div>
 	<div class="timeline-new-email">
-		<button class="btn btn-default btn-new-email btn-xs">
+		{% if(doctype === "Communication") { %}
+			<button class="btn btn-default btn-reply-email btn-xs">
+				{%= __("Reply") %}
+			</button>
+		{% } else { %}
+			<button class="btn btn-default btn-new-email btn-xs">
 			{%= __("New Email") %}
 		</button>
+		{% } %}
 	</div>
     <div class="timeline-items">
 

frappe/public/js/frappe/form/footer/timeline.js

@@ -11,7 +11,7 @@ frappe.ui.form.Timeline = Class.extend({
 	make: function() {
 		var me = this;
 		this.wrapper = $(frappe.render_template("timeline",
-			{})).appendTo(this.parent);
+			{doctype: this.frm.doctype})).appendTo(this.parent);
 
 		this.list = this.wrapper.find(".timeline-items");
 		this.input = this.wrapper.find(".form-control");
@@ -35,15 +35,7 @@ frappe.ui.form.Timeline = Class.extend({
 			}
 		});
 
-		this.email_button = this.wrapper.find(".btn-new-email")
-			.on("click", function() {
-				new frappe.views.CommunicationComposer({
-					doc: me.frm.doc,
-					txt: frappe.markdown(me.input.val()),
-					frm: me.frm,
-					recipients: me.get_recipient()
-				})
-			});
+		this.setup_email_button();
 
 		this.list.on("click", ".toggle-blockquote", function() {
 			$(this).parent().siblings("blockquote").toggleClass("hidden");
@@ -82,6 +74,33 @@ frappe.ui.form.Timeline = Class.extend({
 
 	},
 
+	setup_email_button: function() {
+		var me = this;
+		selector = this.frm.doctype === "Communication"? ".btn-reply-email": ".btn-new-email"
+		this.email_button = this.wrapper.find(selector)
+			.on("click", function() {
+				args = {
+					doc: me.frm.doc,
+					frm: me.frm,
+					recipients: me.get_recipient()
+				}
+
+				if(me.frm.doctype === "Communication") {
+					$.extend(args, {
+						txt: "",
+						last_email: me.frm.doc,
+						recipients: me.frm.doc.sender,
+						subject: __("Re: {0}", [me.frm.doc.subject]),
+					});
+				} else {
+					$.extend(args, {
+						txt: frappe.markdown(me.input.val())
+					});
+				}
+				new frappe.views.CommunicationComposer(args)
+			});
+	},
+
 	refresh: function(scroll_to_end) {
 		var me = this;