Domain Models: Microtec POS

This document outlines the core business entities used in the Microtec POS system. These entities reside in the lib/domain layer and represent the "Source of Truth" for business logic, independent of UI or data storage implementations.

1. Order Management

OrderModel

The central entity representing a sales transaction (Retail or Restaurant).

• UID: Unique identifier for synchronization and local tracking.
• Invoice Number: Generated based on branch, device, year, and a local counter.
• Type: Sale, Return, Reservation, ReturnDish.
• Status: Draft, Hold, Paid, Closed, etc.
• Business Date: Decoupled from system date to handle shifts correctly.
• Components:
  • OrderItemList: Collection of items in the cart.
  • OrderPaymentList: List of payments (supports split payments).
  • OrderOffer & OrderDiscount: Applied promotions.
  • RemovedOrderItem: Audit trail of items removed after being sent to the kitchen.

OrderItem

Represents an individual product entry in an order.

• Quantity: Tracks original and adjusted quantities (for returns/offers).
• Price Details: Handled by OrderItemPrice, tracking taxes and discounts per line.
• Modifiers:
  • OrderItemOption: Add-ons with their own pricing and tax logic.
  • OrderItemIngredient: Removable ingredients (e.g., "No Onions").

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2. Product Catalog

Product

The base definition of an item available for sale.

• Attributes: Code, Barcode, Names (Arabic/Latin), Calories, Preparation Time.
• Taxation: Linked to a Tax entity; supports VAT-inclusive or exclusive pricing.
• Structure:
  • OptionGroup: Defines available add-ons (selection modes: Single/Multiple).
  • ProductIngredient: Standard ingredients that can be modified.
  • ProductSelectedPrice: Dynamically calculated price based on the active price policy.

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3. Customer & Loyalty

CustomersModel

Represents a client profile.

• Loyalty: Tracks pointsBalance and pendingPoints.
• Pricing: Linked to a customerGroupId which can trigger specific price policies.
• LoyaltyExchange: Defines the conversion rate between points and monetary value.

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4. Sessions & Shifts

Session

Manages the lifecycle of a cashier's work period.

• Balance Tracking: Tracks openingBalance and various ending balances (endingCashBalance, endingVisaBalance).
• Tender: A list of Tender objects representing counted cash/card amounts during reconciliation.
• Sync State: Tracks whether the shift has been synchronized to the cloud.

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For data storage details, see DATA_PERSISTENCE.md.