前端面试官丢出代码，让我说说实现了什么功能，看不懂实现了什么业务呀

``/* 请理解这些代码，并说出为什么要这样设计，实现了什么。 */

const BrightMapping = [ 0, 8, 11, 14, 16, 18, 20, 21, 23, 24, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 40, 44, 48, 51, 54, 57, 60, 62, 65, 67, 70, 72, 74, 77, 79, 81, 85, 88, 92, 95, 99, 102, 105, 108, 111, 114, 117, 120, 122, 125, 128, 130, 133, 135, 137, 140, 142, 144, 146, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, 180, 182, 184, 186, 187, 189, 191, 193, 194, 196, 198, 199, 201, 202, 204, 206, 207, 209, 210, 212, 213, 215, 216, 218, 219, 221, 222, 224, 225, 227, 228, 230, 231, 232, 234, 235, 236, 238, 239, 241, 242, 243, 245, 246, 247, 249, 250, 251, 252, 254, 255, ];

const cctBrightMapping = [ 0, 2, 5, 7, 10, 12, 15, 17, 20, 22, 25, 28, 30, 33, 35, 38, 40, 43, 45, 48, 51, 53, 56, 58, 61, 63, 66, 68, 71, 73, 76, 79, 81, 84, 86, 89, 91, 94, 96, 99, 102, 104, 107, 109, 112, 114, 117, 119, 122, 124, 127, 130, 132, 135, 137, 140, 142, 145, 147, 150, 153, 155, 158, 160, 163, 165, 168, 170, 173, 175, 178, 181, 183, 186, 188, 191, 193, 196, 198, 201, 204, 206, 209, 211, 214, 216, 219, 221, 224, 226, 229, 232, 234, 237, 239, 242, 244, 247, 249, 252, 255, ];

const time2hex = (DelayTime) => { if (DelayTime > 0xff >> 1) { return ((DelayTime / 60) << 1) ^ 1; } else { return DelayTime << 1; } };

function hexToBytes(hexStr) { let str = hexStr.replace(/\s/g, "").toLowerCase();

if (str.length % 2 !== 0) { throw new Error("err: data error"); }

let bytes = [];

for (let i = 0; i < str.length; i += 2) { let hexByte = str.substr(i, 2); let decimalByte = parseInt(hexByte, 16); bytes.push(decimalByte); }

return bytes; }

function checksum(data) { data = hexToBytes(data); let end = data[3] + 4; let sum = 0; for (let i = 2; i < end; i++) { sum += data[i] & 0xff; }

let high = sum & 0xff; let low = sum >> 8; return int2hex(~(high + low) & 0xff); }

function int2hex(num) { return num.toString(16).toUpperCase().padStart(2, "0"); }

function isValidHexadecimal(str) { const regex = /^([0-9A-Fa-f]{2}\s[0-9A-Fa-f]{2})$/g; return regex.test(str.toString()); }

const numFormat = (numOrHex) => { const originalValue = numOrHex.toString(); if (originalValue.indexOf(" ") !== -1) { return originalValue; } else { const numValue = parseInt(originalValue); if (!isNaN(numValue)) { const hexString = numValue.toString(16).toUpperCase(); const paddedHexString = hexString.padStart(4, "0"); return ${paddedHexString.slice(0, 2)} ${paddedHexString.slice(2)}; } else { throw new Error("Conversion failed: Input is not a valid number."); } } };

function init(cmd) { return { head: "47 53", CMD: "10", size: null, dBm: "00", uuid: "00 00 00 00 00 00", opc: "80", usbId: "01 FE", dataCmd: null, code: cmd.code || "", deviceName: cmd.deviceName || "", area: numFormat(cmd.area) || "", address: numFormat(cmd.address) || "", action: cmd.action || "", params: cmd.params || "", identity: cmd.identity || "", }; }

let req = 0;

const getReq = () => { req = (req + 1) % 256; return int2hex(req); };

const ScenarioFactory = (scene) => { console.log(scene); return [ int2hex(scene.SceneNo), int2hex(BrightMapping[scene.HighBright]), int2hex(BrightMapping[scene.StandbyBright]), int2hex(cctBrightMapping[scene.CctBright]), int2hex(time2hex(scene.DelayTime)), int2hex(time2hex(scene.DelayTime2)), int2hex( (scene.AlsControlMode << 3) ^ (scene.DelayMode << 2) ^ scene.LightMode ), "00", ].join(" "); };

const getDataCmd = (action, p) => { let params = null; if (isValidHexadecimal(p)) { params = p; } else if (typeof params === "string") { params = int2hex(parseInt(p)); } else { params = p; } return StringExecutoraction; };

function CodedData(dataCmd) { let sendSerial = init(dataCmd); sendSerial.dataCmd = getDataCmd(sendSerial.action, sendSerial.params);

const dataArray = [ sendSerial.dBm, sendSerial.uuid, sendSerial.opc, getReq(), sendSerial.usbId, sendSerial.address, sendSerial.area, sendSerial.dataCmd, ]; let arr = dataArray.join(" "); let size = int2hex(arr.split(" ").length); const outArray = [sendSerial.head, sendSerial.CMD, size, arr]; outArray.push(checksum(outArray.join(" "))); return outArray.join(" "); }

const StringExecutor = { blink: (num) => { return 4D 1C ${num}; }, setScene: (p) => { let SceneNo = int2hex(0x50 + parseInt(p["SceneNo"])); return CD ${SceneNo} + ScenarioFactory(p); }, };

// 入口部分~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

function DecodeData(str) { // 数据统一入口 if (str.length < 20) { return null; } const b = str.split(" "); return { head: b.slice(0, 2).join(" "), CMD: b.slice(2, 3).join(" "), size: b.slice(3, 4).join(" "), dBm: b.slice(4, 5).join(" "), uuid: b.slice(5, 11).join(" "), opc: b.slice(11, 12).join(" "), req: b.slice(12, 13).join(" "), number: b.slice(13, 15).join(" "), cluster: b.slice(15, 17).join(" "), area: b.slice(17, 19).join(" "), dataCmd: b.slice(19, b.length - 1).join(" "), sum: b.slice(b.length - 1).join(" "), }; }

const hexToInt = (hexString) => parseInt(hexString, 16);

const ScenarioParser = (inputString) => { const parts = inputString;

if (parts.length !== 8) { throw new Error("Invalid input string format"); }

return { SceneNo: hexToInt(parts[0]), HighBright: Object.keys(BrightMapping).find( (key) => BrightMapping[key] === hexToInt(parts[1]) ), StandbyBright: Object.keys(BrightMapping).find( (key) => BrightMapping[key] === hexToInt(parts[2]) ), CctBright: Object.keys(cctBrightMapping).find( (key) => cctBrightMapping[key] === hexToInt(parts[3]) ), DelayTime: hexToInt(parts[4]), DelayTime2: hexToInt(parts[5]), AlsControlMode: (hexToInt(parts[6]) >> 3) & 0x07, DelayMode: (hexToInt(parts[6]) >> 2) & 0x01, LightMode: hexToInt(parts[6]) & 0x03, }; };

console.log( DecodeData( "47 53 12 19 BA 50 54 7B 3A 54 05 83 28 1F 91 01 FE 00 01 4F 54 04 FF 51 14 14 14 00 00 D3" ) ); const in_data = "47 53 12 19 BA 50 54 7B 3A 54 05 83 28 1F 91 01 FE 00 01 4F 54 04 FF 51 14 14 14 00 00 D3"; let call_func = null; const g_data = {};

// let temp_data = decodeData(in_data)

// if (temp_data != null) { // if (!g_data[temp_data.uuid]) { // g_data[temp_data.uuid] = {}; // } // console.log(temp_data); // let cmd = temp_data.dataCmd.split(" ") // if (cmd[0] == "4F") { // g_data[temp_data.uuid] = { ...g_data[temp_data.uuid], ...ScenarioParser(cmd.slice(2, 10)) } // }

// call_func = () => { console.log("test"); } // if (call_func != null) { // call_func() // call_func = null; // }

// g_data[temp_data.uuid] = { ...g_data[temp_data.uuid], ...temp_data } // console.log("out~~~~~~~~~~~~~~~~~~~~~~~"); // console.log(g_data[temp_data.uuid]); // //TODO // console.log(); // }

// 测试部分~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

let scene = { SceneNo: 0, HighBright: 22, StandbyBright: 0, CctBright: 0, DelayTime: 0, DelayTime2: 0, AlsControlMode: 2, DelayMode: 1, LightMode: 2, };

let dataCmd = { code: "400", deviceName: 139, area: "00 01", address: "1F 91", action: "setScene", params: scene, identity: "", };

// for (let index = 0; index < 10; index++) { // console.log(CodedData(dataCmd));

// }

export default { CodedData, DecodeData, };