Multi-Location Supermarket Chains: Real-Time Batch & Expiry Valuation in Business Central

codeunit 50200 "Supermarket FEFO Engine"
{
    Access = Public;
    Subtype = Normal;

    [EventSubscriber(ObjectType::Codeunit, Codeunit::"Create Pick", 'OnBeforeCreatePick', '', false, false)]
    local procedure EnforceFEFOPicking(var WarehouseActivityHeader: Record "Warehouse Activity Header"; var IsHandled: Boolean)
    var
        ItemTracking: Record "Item Tracking Code";
        LotNoInformation: Record "Lot No. Information";
    begin
        // Enforce strict FEFO picking order based on Lot Expiration Date
        LotNoInformation.SetCurrentKey("Expiration Date");
        LotNoInformation.SetAscending("Expiration Date", true);
        LotNoInformation.SetFilter("Expiration Date", '>=%1', WorkDate());

        if LotNoInformation.FindFirst() then begin
            // Lock pick line to earliest expiring Lot Number
            WarehouseActivityHeader."FEFO Enforced" := true;
        end;
    end;

    [EventSubscriber(ObjectType::Table, Database::"Item Journal Line", 'OnBeforeItemJournalPost', '', false, false)]
    local procedure PreventExpiredItemPosting(var ItemJournalLine: Record "Item Journal Line")
    var
        ReservationEntry: Record "Reservation Entry";
    begin
        if ItemJournalLine."Entry Type" = ItemJournalLine."Entry Type"::Sale then begin
            ReservationEntry.SetRange("Source ID", ItemJournalLine."Document No.");
            if ReservationEntry.FindFirst() then begin
                if (ReservationEntry."Expiration Date" <> 0D) and (ReservationEntry."Expiration Date" < WorkDate()) then
                    Error('FEFO Violation: Lot %1 for Item %2 expired on %3 and cannot be sold.',
                        ReservationEntry."Lot No.",
                        ItemJournalLine."Item No.",
                        ReservationEntry."Expiration Date");
            end;
        end;
    end;
}