let isLooping = false;
function getMapKeys(map) {
    return Array.from(map).map((it) => it[0]);
}
function workLoop() {
    isLooping = true;
    const prioritys = getMapKeys(Thread.threadMap).sort((a, b) => b - a);
    const curPriority = prioritys[0];
    const curPriorityArray = Thread.threadMap.get(curPriority);
    curPriorityArray.forEach((thread) => {
        thread.samePriorityLength = curPriorityArray.length;
        let taskUnit = thread.taskUnit;
        thread.start();
        while (taskUnit && !thread.shouldYield && !thread.isEmpty) {
            taskUnit = thread.taskUnit = thread.exec();
        }
        if (taskUnit === undefined) {
            thread.destroy();
        }
        else {
            thread.pause();
        }
    });
    if (Thread.isAllEmpty()) {
        isLooping = false;
    }
    else {
        nextTick(workLoop);
    }
}
let channel;
function nextTick(callback) {
    if (window.MessageChannel) {
        if (!channel) {
            channel = new MessageChannel();
            channel.port1.onmessage = callback;
        }
        channel.port2.postMessage("notify");
    }
    else {
        setTimeout(callback, 0);
    }
}
class Thread {
    static create(runner, taskUnit = undefined, options) {
        const thread = new Thread(runner, taskUnit, options);
        Thread.threads.push(thread);
        const newThreadPriority = thread.options.priority;
        const curPriorityArray = Thread.threadMap.get(newThreadPriority);
        if (curPriorityArray) {
            curPriorityArray.push(thread);
        }
        else {
            Thread.threadMap.set(newThreadPriority, [thread]);
        }
        return thread;
    }
    static isAllEmpty() {
        return !Thread.threads.find((thread) => !thread.isEmpty);
    }
    constructor(runner, taskUnit, options) {
        this.runner = undefined;
        this.taskUnit = undefined;
        this.options = {
            priority: 0,
        };
        this.status = "paused";
        this.samePriorityLength = 0;
        this.startTime = 0;
        this.runner = runner;
        this.taskUnit = taskUnit;
        this.options = Object.assign(this.options, options);
    }
    start() {
        this.status = "running";
        this.startTime = Date.now();
        if (!isLooping) {
            workLoop();
        }
    }
    pause() {
        this.status = "paused";
        this.startTime = 0;
    }
    exec() {
        return this.runner(this.taskUnit);
    }
    destroy() {
        Thread.threads.splice(Thread.threads.findIndex((it) => it === this), 1);
        const curPriorityArray = Thread.threadMap.get(this.options.priority);
        curPriorityArray.splice(curPriorityArray.findIndex((it) => it === this), 1);
        if (curPriorityArray.length === 0) {
            Thread.threadMap.delete(this.options.priority);
        }
        this.runner = undefined;
        this.options = undefined;
        this.taskUnit = undefined;
        this.status = "destroyed";
    }
    get shouldYield() {
        return Date.now() > this.startTime + this.yieldInterval;
    }
    get isEmpty() {
        return this.taskUnit === undefined;
    }
    get yieldInterval() {
        return Thread.yieldInterval / this.samePriorityLength;
    }
}
Thread.threads = [];
Thread.threadMap = new Map();
Thread.yieldInterval = 5;
export { Thread };