import { priorityQueue, type AsyncPriorityQueue } from 'async';

export class TaskProcessor {
    private maxParallelTasks: number;
    private taskQueue: AsyncPriorityQueue<() => Promise<void>>;

    constructor(maxParallelTasks: number) {
        this.maxParallelTasks = maxParallelTasks;
        this.taskQueue = priorityQueue(function (task, callback) {
            task().then(() => callback(), (e) => callback(e));
        }, this.maxParallelTasks);
        this.taskQueue.error((e) => {
            console.log("Error in task queue task: " + e);
        })
        console.log(`Task processor created with a maximum of ${maxParallelTasks} parallel tasks`);
    }

    schedule(task: () => Promise<any>, priority = 100): Promise<void> {
        return new Promise((resolve) => {
            this.taskQueue.buffer
            this.taskQueue.push(task, priority, () => resolve());
        })
    }

    unsaturated(): Promise<void> {
        return this.taskQueue.unsaturated();
    }
}