fix(accounts): payment entry unallocated amount

[dj12djdjs]

Continuation of #30504

closes: #29595
closes: #23936

** Allocating References
This shows the unallocated amount being changes as rows become allocated.

** Write Offs
Using the "deductions" table, the unallocated_amount can be manipulated. It's primary use is for rounding, and writeoffs.

** Exchange gain/loss
Using the "losses table, the difference_amount can be manipulated. It's primary use if for declaring the difference between currencies.

[codecov]

Codecov Report

Merging #30927 (263c7ba) into develop (3714e36) will decrease coverage by 0.03%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop   #30927      +/-   ##
===========================================
- Coverage    63.07%   63.03%   -0.04%     
===========================================
  Files          985      985              
  Lines        67272    67277       +5     
===========================================
- Hits         42431    42410      -21     
- Misses       24841    24867      +26     

Impacted Files	Coverage Δ
...ccounts/doctype/payment_request/payment_request.py	67.56% <ø> (ø)
erpnext/regional/india/setup.py	94.24% <ø> (ø)
...xt/accounts/doctype/payment_entry/payment_entry.py	69.33% <100.00%> (+0.23%)	⬆️
...e_sales_analytics/supplier_wise_sales_analytics.py	59.01% <0.00%> (-22.96%)	⬇️
...urity_shortfall/process_loan_security_shortfall.py	93.75% <0.00%> (-6.25%)	⬇️
erpnext/accounts/party.py	78.09% <0.00%> (-4.62%)	⬇️
...pnext/setup/doctype/sales_partner/sales_partner.py	65.21% <0.00%> (-4.35%)	⬇️
erpnext/stock/doctype/warehouse/warehouse.py	77.62% <0.00%> (-3.50%)	⬇️
...e/asset_value_adjustment/asset_value_adjustment.py	86.04% <0.00%> (-3.49%)	⬇️
...eorder_level/itemwise_recommended_reorder_level.py	90.74% <0.00%> (-1.86%)	⬇️
... and 18 more

[dj12djdjs]

Disregard comment about allocation for credit note.

[dj12djdjs]

I'm starting to think the only way to solve this is to separate deductions/writeoffs and exchange rate deductions into separate child tables.

Having a condition that forces unallocated_amount to be zero is not working. It should be produced by addition and subtraction.

The only way I can think to solve this is to subtract exchange deductions from total_deductions. Then calculate the unallocated_amount

[dj12djdjs]

Gonna post some screen recordings in a few hours.

[dj12djdjs]

I don't know why the linter keeps failing. I've run pre-commit run --all-files multiple times and is passing on my machine.

[dj12djdjs]

@deepeshgarg007 This is working. Can you please review.

[dj12djdjs]

@deepeshgarg007 Just checking up, did you have a chance to review this ?

[deepeshgarg007]

@dj12djdjs I am reviewing this and will also take a second opinion internally if we need a separate table for losses

[dj12djdjs]

@dj12djdjs I am reviewing this and will also take a second opinion internally if we need a separate table for losses

If you guys can find a way to make it work in 1 table that would be more convenient.

I don't have much experience in accounting. This is the only way I could make it work.

[dj12djdjs]

@deepeshgarg007 any update from the team on this matter?

[dj12djdjs]

@deepeshgarg007 Is there a time frame for this?

[OneiricIT]

@dj12djdjs does this have any relation to being able to pull credit note amounts sitting on account as payment method for other invoices?
Reference:
#28775

[dj12djdjs]

@dj12djdjs does this have any relation to being able to pull credit note amounts sitting on account as payment method for other invoices? Reference: #28775

@OneiricIT no, this PR is just about unallocated calculation method

[deepeshgarg007]

Closing this since a new PR is raised for this.