增加未选择赠品时去结算的提醒. code review by XWG

@@ -9,6 +9,7 @@ var $ = require('jquery'),
     Hammer = require('yoho.hammer');
 
 var chosePanel = require('./chose-panel'),
+    dialog = require('../me/dialog'),
     tip = require('../plugin/tip');
 
 var $cartContent = $('.cart-content');
@@ -18,6 +19,48 @@ var navHammer,
 
 var hasChecked = $('.cart-content:not(.hide) .icon-cb-checked').length > 0 ? true : false; //是否有选中商品
 
+function shouldSelectGift() {
+    var $freebie = $('.freebie');
+
+    if ($freebie.length <= 0) {
+        return false;
+    }
+
+    return true;
+}
+
+function shouldLowStocks() {
+    var $lowStocks = $('.low-stocks'),
+        result = false;
+
+    if ($lowStocks.length <= 0) {
+        return result;
+    }
+
+    $lowStocks.each(function(idx, item) {
+        if ($(item).parent().parent().parent().siblings('.checkbox').hasClass('icon-cb-checked')) {
+            result = true;
+            return false;
+        }
+    });
+
+    return result;
+}
+
+function showChooseGifDialog() {
+    dialog.showDialog({
+        dialogText: '您还未选择赠品，是否去选择赠品',
+        hasFooter: {
+            leftBtnText: '我不要赠品',
+            rightBtnText: '去选择'
+        }
+    }, function() {
+        window.location.href = $('.freebie').find('a').attr('href');
+    }, function() {
+        window.location.href = '/cart/index/orderEnsure?cartType=' + cartType;
+    });
+}
+
 require('./good');
 
 lazyLoad($('img.lazy'));
@@ -65,7 +108,11 @@ $('.freebie').on('touchend', function() {
 });
 
 $('.btn-balance').on('touchend', function() {
-    if ($('.low-stocks').length > 0) {
+    if (shouldSelectGift()) {
+        showChooseGifDialog();
+        return false;
+    }
+    if (shouldLowStocks()) {
         tip.show('库存不足无法结算');
         return false;
     }

@@ -33,7 +33,7 @@ dialogTpl = '<div id="dialog-wrapper" class="dialog-wrapper">' +
 
 dialogTemplate = Handlebars.compile(dialogTpl);
 
-exports.showDialog = function(data, callback) {
+exports.showDialog = function(data, callback, callbackForLeft) {
 
     var dialogStr = dialogTemplate(data),
         $dialogBox,
@@ -76,6 +76,9 @@ exports.showDialog = function(data, callback) {
     dialogWrapperHammer.on('tap', function(event) {
 
         if ($(event.target).hasClass('dialog-left-btn')) {
+            if (typeof callbackForLeft === 'function') {
+                callbackForLeft();
+            }
             $dialogWrapper.fadeOut();
         } else if ($(event.target).hasClass('dialog-right-btn')) {
             callback();