/*
 * Copyright (C) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

class PerfCallChainThread extends Worker {
    busy: boolean = false;
    taskMap: any = {};
    uuid(): string {
        // @ts-ignore
        return ([1e7] + -1e3 + -4e3 + -8e3 + -1e11)
            .replace(/[018]/g, (c: any) => (c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16));
    }

    queryFunc(name: string, args: any, handler: Function, action: string | null) {
        this.busy = true;
        let id = this.uuid();
        this.taskMap[id] = handler
        let msg = {
            id: id,
            name: name,
            action: action || "exec",
            params: args,
        }
        this.postMessage(msg);
    }

}

export class PerfCallChainPool {
    maxThreadNumber: number = 0;
    works: Array<PerfCallChainThread> = [];

    close = async () => {
        for (let i = 0; i < this.works.length; i++) {
            let thread = this.works[i];
            thread.terminate();
        }
        this.works.length = 0;
    }

    init = async () => {
        await this.close();
        let thread = new PerfCallChainThread("trace/component/chart/PerfDataQuery.js", {type: "module"})//trace/component/chart/PerfDataQuery.js
        thread!.onmessage = (event: MessageEvent) => {
            thread.busy = false;
            let fun = thread.taskMap[event.data.id];
            if (fun) {
                fun(event.data.results);
            }
            Reflect.deleteProperty(thread.taskMap, event.data.id);
        }
        thread!.onmessageerror = e => {
        }
        thread!.onerror = e => {
        }
        thread!.busy = false;
        this.works?.push(thread!);
    }

    submit(name: string, args: any, handler: Function, action: string | null) {
        let noBusyThreads = this.works.filter(it => !it.busy);
        let thread: PerfCallChainThread
        if (noBusyThreads.length > 0) { //取第一个空闲的线程进行任务
            thread = noBusyThreads[0];
            thread.queryFunc(name, args, handler, action)
        } else { // 随机插入一个线程中
            thread = this.works[Math.floor(Math.random() * this.works.length)]
            thread.queryFunc(name, args, handler, action)
        }
    }

}

export const callChainsPool = new PerfCallChainPool()