Hello my friends.
Here i tested and post real chance for gifts in winterfest event.
This is a table for gift for 5000 Candy.

~2% for 10 Gingerbread Cookies.

~2% for 25 Gingerbread Cookies.

~1-2% for 10 Catalysts.

This is total scam!

Rewards for 20000 candy gifts is also scam!
It got not 50% for Gingerbread Cookies. Just 25% to get 25 GB cookies from 20k gift.

And here rewards from 30 000 gifts for 1000 Candy. 

Best way to get Gingerbread Cookies is 20k gifts. But, for 2 000 000 candy you will get only ~625 Gingerbread Cookies.

Depends on your luck also.

And for totem you will need ~17 800 000 Candy. 
I spend 600 000 emeralds and got just 3 000 000 Candy. total scam!

Most chance are not fair. Be care with them.