// import { writeLog } from "./Log.js";

import { writeErrLog } from "./Log.js";

/**
 * 对buffer进行切割
 */
export default class UnitCache {
    constructor() {
        // this.spliceUnits = [];
        this.cacheBuf = [];
    }

    put(buf) {
        /**
         * 拼接两个unit8Array
         */
        const target = new Uint8Array(buf);
        if (this.cacheBuf.byteLength) {
            const source = this.cacheBuf;
            this.cacheBuf = new Uint8Array(newUnit8.byteLength + this.cacheBuf.byteLength);
            this.cacheBuf.set(source, 0);
            this.cacheBuf.set(target, source.byteLength);
        } else {
            this.cacheBuf = target;
        }
        // 00 00 00 01 或者 00 00 01 分割码
        /**
         * 1.找数值为00的
         * 2.判断相邻的两个或者三个字节是否满足条件
         */
        let index = 0;
        let subCodeStartIndexs = [];
        while (index < this.cacheBuf.byteLength) {
            if (this.cacheBuf[index] === 0 && this.cacheBuf[index + 1] === 0) {
                if (this.cacheBuf[index + 2] === 1) {
                    // writeLog("00 00 01:" + index);
                    subCodeStartIndexs.push({
                        index,
                        len: 3
                    });
                    index += 3;
                } else if (this.cacheBuf[index + 2] === 0 && this.cacheBuf[index + 3] === 1) {
                    // writeLog("00 00 00 01:" + index);
                    subCodeStartIndexs.push({
                        index,
                        len: 4
                    });
                    index += 4;
                } else {
                    index++;
                }
            } else {
                index++;
            }
        }

        let spliceUnits = [];
        const indexsLength = subCodeStartIndexs.length;
        for (let index = 0; index < indexsLength; index++) {
            const sub = subCodeStartIndexs[index];
            const nextSub = subCodeStartIndexs[index + 1];
            if (nextSub) {
                const slice = this.cacheBuf.subarray(sub.index + sub.len, nextSub.index);
                spliceUnits.push(slice);
            }
        }
        this.cacheBuf = this.cacheBuf.subarray(subCodeStartIndexs[indexsLength - 1]);

        return spliceUnits;
    }
}