import { randomUUID } from "crypto";
type Priority = "high" | "normal" | "low";
type QueueItemStatus = "pending" | "processing" | "completed" | "failed";
interface QueueRequest {
id?: string;
type: string;
payload: Record<string, unknown>;
priority?: Priority;
}
interface QueueItem {
id: string;
type: string;
payload: Record<string, unknown>;
priority: Priority;
status: QueueItemStatus;
createdAt: Date;
startedAt: Date | null;
completedAt: Date | null;
result: unknown;
error: string | null;
}
interface QueueStatus {
pending: number;
processing: number;
completed: number;
failed: number;
averageWaitTime: number;
}
const priorityWeight: Record<Priority, number> = {
high: 3,
normal: 2,
low: 1,
};
const queue: QueueItem[] = [];
const history: QueueItem[] = [];
const MAX_HISTORY = 500;
export function enqueueRequest(req: QueueRequest): QueueItem {
const item: QueueItem = {
id: req.id || randomUUID(),
type: req.type,
payload: req.payload,
priority: req.priority || "normal",
status: "pending",
createdAt: new Date(),
startedAt: null,
completedAt: null,
result: null,
error: null,
};
queue.push(item);
queue.sort((a, b) => priorityWeight[b.priority] - priorityWeight[a.priority]);
return item;
}
export function processNext(): QueueItem | null {
const index = queue.findIndex((item) => item.status === "pending");
if (index === -1) return null;
const item = queue[index];
item.status = "processing";
item.startedAt = new Date();
return item;
}
export function completeRequest(id: string, result: unknown): QueueItem | null {
const index = queue.findIndex((item) => item.id === id);
if (index === -1) return null;
const item = queue[index];
item.status = "completed";
item.completedAt = new Date();
item.result = result;
queue.splice(index, 1);
history.unshift(item);
if (history.length > MAX_HISTORY) {
history.length = MAX_HISTORY;
}
return item;
}
export function failRequest(id: string, error: string): QueueItem | null {
const index = queue.findIndex((item) => item.id === id);
if (index === -1) return null;
const item = queue[index];
item.status = "failed";
item.completedAt = new Date();
item.error = error;
queue.splice(index, 1);
history.unshift(item);
if (history.length > MAX_HISTORY) {
history.length = MAX_HISTORY;
}
return item;
}
export function getQueueStatus(): QueueStatus {
const completedItems = history.filter((i) => i.status === "completed");
let totalWait = 0;
for (const item of completedItems) {
if (item.startedAt) {
totalWait += item.startedAt.getTime() - item.createdAt.getTime();
}
}
const averageWaitTime =
completedItems.length > 0 ? totalWait / completedItems.length : 0;
return {
pending: queue.filter((i) => i.status === "pending").length,
processing: queue.filter((i) => i.status === "processing").length,
completed: history.filter((i) => i.status === "completed").length,
failed: history.filter((i) => i.status === "failed").length,
averageWaitTime,
};
}
export function getQueueHistory(limit: number = 50): QueueItem[] {
return history.slice(0, limit);
}
