[IMP] accounting: add loan management

This has been done in https://github.com/odoo/enterprise/pull/68698

closes odoo/documentation#11235

X-original-commit: 8f73708332
Signed-off-by: Xavier Platteau (xpl) <xpl@odoo.com>
Signed-off-by: Ricardo Gomes Rodrigues (rigr) <rigr@odoo.com>

content/applications/finance/accounting/bank.rst

@@ -193,3 +193,4 @@ Payments` tab. To display the outstanding accounts column, click on the toggle b
    bank/reconciliation
    bank/reconciliation_models
    bank/foreign_currency
+   bank/loans

content/applications/finance/accounting/bank/loans.rst

@@ -0,0 +1,70 @@
+================
+Loans management
+================
+
+Odoo's loan management gives a comprehensive list of all loans undertaken by your company in order
+to maintain a holistic and forecasted view of upcoming due dates (e.g., cash forecast). Set up
+amortization schedules—or import them—and let Odoo automatically handle monthly interest and
+principal adjustments so that your financial reports are always accurate with minimal effort.
+
+Create a new loan
+-----------------
+
+Create a new loan by going to :menuselection:`Accounting --> Accounting --> Loans`. When creating a
+new loan, there are three options for how to create amortization schedules:
+
+- importing it from a supported file;
+- calculating it from multiple input values (e.g., the :guilabel:`Amount Borrowed`, the
+  :guilabel:`Duration`, etc.) using the :guilabel:`Compute` button;
+- manually filling in the lines of the schedule.
+
+In each case, three different fields are required for each line of the amortization schedule: the
+:guilabel:`Date`, the :guilabel:`Principal`, and the :guilabel:`Interest`.
+
+The :guilabel:`Amount Borrowed`, :guilabel:`Interest`, and :guilabel:`Duration` fields will be red
+if the sum of the lines does not match the total of the amortization schedule lines.
+
+Loan entries mechanism
+----------------------
+
+When the amount borrowed is credited to a bank account, it should be transferred to a long-term
+account (defined in the :guilabel:`Loan Settings` tab). Then, upon the validation of the loan, Odoo
+creates the necessary journal entries so that there is always a holistic and forecasted view of
+upcoming due dates. The entire process is completely automated with a long-term and short-term
+principal reclassification mechanism.
+
+For each line of the amortization schedule, Odoo creates the following entries:
+
+A payment entry on the same date that
+  - debits the principal amount to the long-term account;
+  - debits the interest amount to the expense account;
+  - credits the payment amount to the short-term account: this is the amount that will be
+    withdrawn by the bank.
+
+A reclassification entry on the same date that
+  - debits the sum of the principal amounts of the next 12 months to the long-term account;
+  - credits the sum of the principal amounts of the next 12 months to the short-term account.
+
+A reversed entry of the reclassification entry on *the next day* that simply reverses the previous
+one.
+
+With this mechanism, month after month, the short-term account is always up to date with the
+current short-term due amounts.
+
+Closing a loan
+--------------
+
+By default, a loan will be closed whenever its last payment entry is posted. However, it can also
+be manually closed (e.g., because it is being paid off early) by clicking on the :guilabel:`Close`
+button. A wizard will appear asking from which date the loan should be closed. All draft entries
+after this date will be deleted too.
+
+A loan can also be cancelled. In that case, all entries will be deleted even if they were already
+posted.
+
+Loans Analysis Report
+---------------------
+
+By going to :menuselection:`Accounting --> Reporting --> Loans Analysis`, you can access a
+report with a pivot view of your ongoing loans. By default, the report shows the principal,
+interest, and total payment for each year for the loan duration.