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  meBUY PRE-ORDER SYSTEM TUTORIAL
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  Pre-orders allow customers to reserve China-warehouse products before
  they arrive in Ghana. A logistics shipment is automatically created
  for each pre-order.

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  1. FOR CUSTOMERS — PLACING A PRE-ORDER
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  1.1 Finding Pre-Order Products
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    • Browse the store for products
    • Look for the "China warehouse" badge on product pages
    • These products are shipped from China via our logistics network

  1.2 Placing a Pre-Order
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    • On a China-warehouse product page, click "Pre-Order from China"
    • Fill in the pre-order form:
      - Quantity — How many units you want
      - Shipping Mark — Your logistics identifier (MEB-XXXXX...)
        If you don't have one, the system will generate one for you
    • Submit the pre-order
    • You'll see a confirmation with your pre-order details

  1.3 What Happens Next (Automatic)
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    • A PreOrder record is created in the system
    • A Logistics Shipment is automatically created:
      - Tracking number is generated
      - Initial status: "Goods at China Warehouse"
      - Sender defaults to "China Vendor / China Warehouse"
    • The shipment enters the logistics pipeline
    • You can track it using the Tracking Number or Shipping Mark

  1.4 Viewing Your Pre-Orders
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    • Login to your account
    • Navigate to: My Account → Pre-Orders
    • See all your pre-orders with status
    • Click any pre-order to view details

  1.5 Cancelling a Pre-Order
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    • On the pre-order detail page, click "Cancel Pre-Order"
    • The pre-order status will be updated to "cancelled"
    • Note: Cancellation policies may apply

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  2. FOR ADMINS — MANAGING PRE-ORDERS
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  2.1 Viewing Pre-Orders
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    • Pre-orders are visible in the Logistics > Shipments section
    • Filter by Source = "pre_order" to see pre-order shipments
    • Each shipment links back to the original pre-order

  2.2 Pre-Order vs Regular Order
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    Pre-Orders are for China warehouse products only.
    They create logistics shipments with source = "pre_order".
    
    Regular Orders with China items also create logistics shipments,
    but with source = "order".

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  3. SYSTEM FLOW (Technical)
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  When a pre-order is placed:
    1. PreOrderController@store validates:
       - Product exists and warehouse === 'china'
       - Customer is authenticated with role 'customer'
    2. PreOrder record is created
    3. PreOrderPlaced event is dispatched
    4. CreateLogisticsShipmentForPreOrder listener runs:
       - Checks if pre-order warehouse === 'china'
       - Finds or creates a logistics Customer by shipping mark
       - Creates Shipment with:
         - tracking_number (generated)
         - shipping_mark (from pre-order)
         - source = 'pre_order'
         - sender: China Vendor / China Warehouse
         - receiver: customer's details
         - status_history: at_china_warehouse
         - items: from pre-order product
       - Links pre_order_id to the shipment
    5. The shipment is now in the logistics pipeline
    6. Admin updates status through the normal workflow

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  4. DIFFERENCES: Pre-Order vs Checkout Order with China Items
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  Pre-Order:
    • Accessed via "Pre-Order from China" button on product page
    • Creates ONLY a logistics shipment (no marketplace order)
    • Source = "pre_order"
    • No payment collected at time of pre-order

  Checkout Order with China Items:
    • Accessed via normal cart → checkout flow
    • Creates a marketplace Order AND a logistics shipment
    • Source = "order"
    • Payment collected at checkout
    • Both Ghana and China items can be in the same cart