Help desk recent ticket actions with a stack

The game-support team needs to undo a mistaken player-report update. If a specialist changes the assignee and then changes the priority on a matchmaking report, the priority change must be undone first. This is different from the assignment queue, which gives reports to specialists in arrival order.

The C# solution

Store each reversible update as an action. The newest action goes on top of the stack, so it is the first action removed.

public record TicketAction(string TicketId, string Description);

var recentActions = new Stack<TicketAction>();

recentActions.Push(new("GS-2042", "Changed assignee to Priya"));
recentActions.Push(new("GS-2042", "Changed priority from 2 to 1"));

TicketAction actionToUndo = recentActions.Pop();
Console.WriteLine(actionToUndo.Description); // Changed priority from 2 to 1

What works

Stack<T> makes the last-in, first-out rule explicit. Push records a new action and Pop retrieves the most recent action, making multi-step undo behavior straightforward.

The limitation that remains

A stack can undo the top action, but it cannot efficiently undo an older action while keeping newer actions valid. It also stores action history, not the current ticket by ID or the order in which tickets should be assigned. Those remain separate dictionary and queue responsibilities.

The stack is the recency policy for reversible actions. It should remain separate from arrival order and urgency.