<?php
/**
 * Invoice Item Fields Constants
 *
 * @package Easy_Invoice
 * @subpackage Constants
 */

namespace EasyInvoice\Constants;

/**
 * InvoiceItemFields Class
 * 
 * Defines constants for invoice item field and meta keys.
 */
class InvoiceItemFields {
    // When stored as posts
    public const POST_TYPE = 'easy_invoice_item';
    public const INVOICE_ID = '_easy_invoice_item_invoice_id';
    
    // Item properties - same keys used for both post meta and array keys
    public const NAME = 'name';
    public const DESCRIPTION = 'description';
    public const QUANTITY = 'quantity';
    public const PRICE = 'price';
    public const TAXABLE = 'taxable';
    
    // Properties only meaningful in associative array context
    public const ID = 'id';          // Used when stored in arrays
    public const INVOICE_ID_ARR = 'invoice_id'; // Used when stored in arrays
    public const AMOUNT = 'amount';  // Calculated from quantity * price
} 