AutoFill field based on outcome of multiple other.
I'm completely new to this so forgive me but I'm going to ask quite a lot. I'm trying to make an app for employees to submit overtime. I'm using data from a SharePoint list. I have a drop down field that offers either "Warehouse" or "Location". Depending on the choice here, I'd like another field (Job Name) to either be autofilled with "Warehouse" (and preferably greyed out) or left open and editable if "Location" is selected. On top of this, I'm going to have another choice field with "Weekend" - (yes/no). When both weekend and warehouse are selected, £60 will be added to an "Earnings" field. When both "Location" and "Weekend" are selected, £150 will be added. When just "Loaction" is selected, £45 will be added.
Now it gets even more complicated. I want to have 3 fields for "Start Time", "End Time" and "Lunch". I then would like to have the app work out the total overtime based on anything over 9hrs + 1hr for lunch being considered overtime, and add it to an "Overtime" field (and grey out if possible).
So the hours will go into an "Overtime" field, and I'll use that to multiply by 15 for the "Earnings" field. But I need the £60 from "weekend" and "Warehouse" to stay as a minimum (so anything under 4hrs will just leave £60 in there), £150 from "Weekend" and "Location" to stay as a minimum (so anything under 10hrs will revert to £150) and £45 from just "Location" to stay as a minimum (only hours past 10 total will add to it).
I know most people are probably just going to tell me to pay someone to make an app for me, unfortunately that's not an option. Just thought I'd give it a shot.