Customize WooCommerce Product AddOn Plugin - 27/04/2018 10:18 EDT

WooCommerce Product AddOn Plugin needs customized code. Currently the plugin allows a flat price upcharge (US dollar) or no upcharge to an AddOn product selection. I want it to also include a percentage upcharge, so we need to add a selection on the screen to choose either unit or percentage upcharge, and create the appropriate code for the percentage upcharge choice. Example: if I want a user to choose red or blue with no upcharge, I can add that selection using this plugin selecting it as a dropdown, checkbox, or radial button and a field for an upcharge appears. If we put something in that field, the system will add that value to the overall price. I want to have a dropdown to choose whether that upcharge is a flat upcharge or a percentage. If we put in the number 5 and choose percent, then we multiply the total price by 1.05 (100% + 5% in the field, converted to percentage as a decimal) and replaces the current total by the new total. If the field is left blank, it does nothing to the total.