Apply guided scheduling interface patterns

webui/src/features/scheduling/schedulingViewModel.ts

@@ -35,6 +35,21 @@ export type SchedulingRequestGroups = {
   other: SchedulingRequest[];
 };
 
+export type SchedulingLifecycleStageId = "prepare" | "participate" | "decide";
+
+export type SchedulingLifecycleStageState =
+  | "complete"
+  | "current"
+  | "locked"
+  | "stopped";
+
+export type SchedulingLifecycleStage = {
+  id: SchedulingLifecycleStageId;
+  state: SchedulingLifecycleStageState;
+  current: boolean;
+  locked: boolean;
+};
+
 export type SchedulingSortPhase =
   | "unanswered"
   | "answered"
@@ -282,6 +297,37 @@ export function schedulingRequestIsPast(
   return slotEnds.every((value) => Number.isFinite(value) && value < now.getTime());
 }
 
+export function schedulingLifecycleStages(
+  status: SchedulingRequest["status"]
+): SchedulingLifecycleStage[] {
+  const currentIndex = status === "draft"
+    ? 0
+    : status === "collecting" || status === "cancelled"
+      ? 1
+      : 2;
+  const completedThrough = status === "draft"
+    ? -1
+    : status === "collecting" || status === "cancelled"
+      ? 0
+      : status === "closed"
+        ? 1
+        : 2;
+  const stopped = status === "cancelled";
+
+  return (["prepare", "participate", "decide"] as const).map((id, index) => {
+    const current = index === currentIndex;
+    const locked = index > completedThrough + 1;
+    const state: SchedulingLifecycleStageState = stopped && current
+      ? "stopped"
+      : index <= completedThrough
+        ? "complete"
+        : current
+          ? "current"
+          : "locked";
+    return { id, state, current, locked };
+  });
+}
+
 export function schedulingInvitationActionBlocks(
   request: SchedulingRequest,
   participant: SchedulingParticipant,