JavaScript Dynamic button with popup

I need to give my clients a little java script code, similar to google analitic (see attachment) The idea is they will insert this code in their php or asp or whatever language. They will need to put their custom info [login to view URL](['_addItem', '$order[id]', // order ID - required '$items', // SKU/code - required '$iteminfo[title]', // product name '$sub_info[title] $cat_info[title] $rx_stat', // category or variation and then the script has to generate the button [OPEN], that when you click on that button it will open the POPUP window with all info above in the url like this ([login to view URL] the design of the button (size, color, title) has to be generated from the server. So we can change the design of the button later and clients will not have to change the code.