Leave Encashment based on Salary Component

[PositronPiercer]

Let me start by explaining the current process of Leave encashment in HRMS.
While configuring encashment on a leave type, we get the following options

One of them is the Earning Component. Here it seemed to me that the calculation for encashment would be (no. of encashable days/total working days in a month) * earning component amount. For example, if someone's Basic component turns out to be INR 100 and his encashable leaves are 10 then his amount would be 10/26 * 100 , assuming 26 working days.

However, the way it works now is you have to specify a fixed amount in the Leave Encashment Amount Per Day (INR) field of the salary structure,

The amount is the same for all employees with the same salary structure.

Currently, there is no way to calculate the encashment amount based on a salary component. I have checked the code in the set_encashment_amount function here.
This is a requirement in my organization and also seems to be the case for others as seen in this issue #2537

Here is my proposal for this feature.

Add an option called Encashment Policy in salary structure for choosing how we want the encashment to work.
- Fixed amount : works same as now
- Based on salary component : In this case the calculation will be based on the value of the salary component of that particular employee for that month.

This would require code changes in two places

1. Addition of a new field called Encashment Policy in Salary Structure doctype.
2. Logic change in the set_encashment_amount function in leave_encashment.py file. THe code will now calculate the amount dependending on the value of Encashment Policy.

I wanted feedback from the maintainers before I start any development.
Looking forward to your comments!
Thanks.

[PositronPiercer]

@ruchamahabal @asmitahase