# Purchase Advance Payment

This module allows creating advance payments directly from purchase orders.
When an advance payment is created, a deposit line is automatically added to the PO.
The journal entry uses the expense account from the default advance payment product 
and the outstanding payment account from the selected cash/bank journal.

## Features

- Create advance payments directly from Purchase Order form
- Automatic deposit line creation in PO
- Proper accounting entries using:
  - Expense account from default advance payment product
  - Outstanding payment account from selected journal
- Payment remains in draft state for review before posting
- View all advance payments linked to a PO
- Deposit line automatically updates when payment is posted

## Configuration

1. **Set Default Advance Payment Product**
   - Go to **Purchase > Configuration > Settings**
   - Scroll to **Advance Payment** section
   - Set the **Default Deposit Product** - this product's expense account will be used for advance payment journal entries

2. **Configure Outstanding Payment Accounts** (Choose one option)
   
   **Option A: Journal-Specific** (for multiple banks)
   - Go to **Accounting > Configuration > Journals**
   - Open each journal > **Outgoing Payments** tab
   - Set **Outstanding Payments Account** in payment methods
   
   **Option B: Company Default** (for single bank)
   - Go to **Accounting > Configuration > Settings**
   - Set **Outstanding Payments Account** in Default Accounts section
   
   Note: Journal-specific accounts take priority over company default.

## Usage

### Creating an Advance Payment

1. Open a Purchase Order (must be in confirmed state)
2. Go to **Advance Payments** tab
3. Click **Create Advance Payment** button
4. Fill in the wizard:
   - **Journal**: Select cash or bank journal
   - **Amount**: Enter advance payment amount
   - **Date**: Payment date
   - **Memo**: Optional description
5. Click **Confirm**
6. The payment is created in draft state for review
7. A deposit line is automatically added to the PO with negative amount
8. Review the payment and click **Confirm** to post it

### Journal Entry Accounts

When the payment is posted, the journal entry will use:
- **Debit**: Expense account from the default advance payment product
- **Credit**: Outstanding payment account from the selected journal

### Vendor Bill Creation

When creating a vendor bill from the PO:
1. The deposit line will be included in the bill
2. The deposit reduces the total amount payable
3. The advance payment is properly accounted for

## Technical Details

- Module creates a deposit product line in the PO with negative price
- Payment model is extended to handle advance payment accounting
- Journal entries are customized to use correct accounts
- Deposit line updates automatically when payment is posted

## Known Issues

- None