Untitled

digraph Level1DFD {
    rankdir=TB;
    node [shape=rectangle, style=rounded, fontsize=11];

    // External Entities
    Owner [label="Owner (Admin)", shape=box];
    Employee [label="Employee (Staff)", shape=box];
    Customer [label="Customer", shape=box];
    Payment [label="Payment System", shape=box];

    // Processes
    P1 [label="1.0 User & Access\nManagement"];
    P2 [label="2.0 Inventory\nManagement"];
    P3 [label="3.0 Customer\nManagement"];
    P4 [label="4.0 Reservations &\nRentals"];
    P5 [label="5.0 Billing &\nPayments"];
    P6 [label="6.0 Reports &\nAnalytics"];
    P7 [label="7.0 System\nSettings"];

    // Data Stores
    D1 [label="D1: Inventory DB", shape=parallelogram];
    D2 [label="D2: Customer DB", shape=parallelogram];
    D3 [label="D3: Staff Accounts DB", shape=parallelogram];
    D4 [label="D4: Transactions DB", shape=parallelogram];
    D5 [label="D5: Reports Archive", shape=parallelogram];

    // Flows
    Owner -> P1 [label="Manage staff & roles"];
    Owner -> P7 [label="System configs"];

    Employee -> P2 [label="Update item status"];
    Employee -> P4 [label="Create rental"];

    Customer -> P3 [label="Register / Update info"];
    Customer -> P4 [label="Reservation request"];

    P1 -> D3 [label="Save staff credentials"];
    D3 -> P1 [label="Staff roles"];

    P2 -> D1 [label="Update stock"];
    D1 -> P2 [label="Inventory records"];

    P3 -> D2 [label="Save customer"];
    D2 -> P3 [label="Customer info"];

    P4 -> D4 [label="Save transaction"];
    D4 -> P4 [label="Rental records"];

    P4 -> P2 [label="Update inventory"];
    P4 -> P5 [label="Billing details"];

    P5 -> Payment [label="Payment/Refund request"];
    Payment -> P5 [label="Confirmation"];

    P6 -> D5 [label="Save reports"];
    D1 -> P6 [label="Inventory data"];
    D2 -> P6 [label="Customer data"];
    D4 -> P6 [label="Transaction data"];
    D5 -> P6 [label="Past reports"];

    P6 -> Owner [label="Reports & Dashboard"];
    P4 -> Employee [label="Due return alerts"];
}