Sales Invoice User Guide
========================

Prerequisites
-------------

Before creating Sales Invoices, confirm:

1. You are logged in and have access to an Entity.
2. The Entity has a default Chart of Accounts.  If it does not, the Sales
   Invoice flow provisions the default CoA and sales/tax account presets.
3. At least one active Customer exists.
4. At least one sellable Item exists (Product/Service).

Create a Sales Invoice
----------------------

1. Open ``Sales Invoices`` from the invoice list screen.
2. Click ``Create Sales Invoice``.
3. Fill Ledger Invoice fields:
   * Customer
   * Draft date
   * Terms
   * Cash account
   * Receivable account
   * Deferred revenue account
4. Fill sales invoice fields:
   * Sales channel / external order info
   * Ship-to address
   * Tax mode and optional tax preset
   * Optional manual GST/PST/HST/US rates
   * Shipping amount / discount amount
5. Submit the form.

After creation
--------------

The system creates:

* A regular ``django_ledger.InvoiceModel`` record.
* A linked ``SalesInvoiceProfile``.
* A tax snapshot for aggregated and per-line values.
* Default sales revenue and sales-tax payable accounts if they were missing.
* A ``SalesTaxAccountMapping`` for GST/PST/HST/US sales tax routing.

Add invoice items
-----------------

To include line items, open the Sales Invoice editor and add rows in the
``Line Items`` section.  The account dropdown is pre-filled with operational
income accounts such as Product Sales, Service Revenue, Freight Revenue, and
E-commerce Sales.  The Sales Invoice tax snapshot recalculates automatically
after item changes.