Developing a script for Gmail (Google app script)

- There's a button available when I'm reading my emails in gmail (or another way of running the script) - When the button is pressed, 3 pieces of information is gathered as follows: --1-- email address, which is one of the following: ---1.1--- the "from" email address, if the sender is not mailchimp ---1.2--- otherwise, an email address mentioned in the body of the email, inside a specific tag (easy to find) --2-- category, which is one of the following: ---2.1-- the name of the recipient (me), if it's one of the 4 existing categories ---2.2-- otherwise, the script has to show a list of categories and ask me for it --3-- items, that should be asked from me. there are about 40 numbered items in each category. the script has to show me numbered checkboxes for those items and let me select one or more. - then the script has to forward one or more emails, based on the selections before. each items in each category is an existing email in my gmail account (or in another form, if it makes it easier for you). They need to be forwarded to the email address we've recognized before. I hope this specifies the whole project :)