Discordのbotをよりよいプログラムにしたい。

const Discord = require('discord.js');
const fetch = require('node-fetch');
const { createCanvas, loadImage } = require('canvas');
const { channelLink, ChannelType } = require('discord.js');

const webhookUrl = 'WEBHOOK_URL'; //Replase with your webhook URL
const earthquakeApiUrl = 'http://www.jma.go.jp/bosai/quake/data/list.json';
const regionApiUrl = 'http://www.jma.go.jp/bosai/common/const/area.json';
const canvasWidth = 800;
const canvasHeight = 600;
const intensityColors = [
    '#00ff00', //Intensity 1
    '#ffff00', //Intensity 2
    '#ffa000', //Intensity 3
    '#ff0000', //Intensity 4
    '#800080', //Intensity 5-
    '#800080', //Intensity 5+
    '#800080', //Intensity 6-
    '#800080', //Intensity 6+
    '#800080', //Intensity 7
];

//Initialize Discord client
const client = new Discord.Client();

//Fetch region data
let regionData;
fetch(regionApiUrl)
    .then(res => res.json())
    .then(data => {
        regionData = data;
    });

//Create canvas and draw regions
const canvas = createCanvas(canvasWidth, canvasHeight);
const context = canvas.getContext('2d');
context.fillStyle = '#ffffff';
context.fillRect(0, 0, canvasWidth, canvasHeight);
context.font = 'bold 20px sans-serif';
context.textAlign = 'center';
context.textBaseline = 'middle';
for (let i = 0; i < regionData.length; i++) {
    const region = regionData[i];
    context.fillStyle = intensityColors[region.color - 1] || '#000000';
    context.fillRect(region.x, region.y, region.width, region.height);
    context.fillStyle = '#000000';
    context.fillText(region.name, region.x + region.width / 2, region.y + region.height / 2);
}

//Draw text at the bottom of the canvas
context.font = 'bold 12px sans-serif';
context.textAlign = 'right';
context.fillStyle = '#000000';
context.fillText('Data by JMA', canvasWidth - 5, canvasHeight - 15);
context.fillText('©Shihiro 2023 All Right Reserved.', canvasWidth - 5, canvasHeight - 5);

//Intialize last earthquake data
let lastEarthquakeData = [];

//Fetch earthquake data every 500ms
setInterval(() => {
    fetch(earthquakeApiUrl)
    .then(res => res.json())
    .then(data => {
        //Check if there is a new earthquake
        if(JSON.stringify(data) !== JSON.stringify(lastEarthquakeData)){
            lastEarthquakeData = data;

            //format earthquake data
            const massage = '**地震情報**\n${data[0].time.slice(0, 16)}に発生\nマグニチュード : ${data[0].magnitude}\n深さ : ${data[0].depth}km\n最大震度 : ${data[0].maxIntensity}';

            //Create earthquake map image
            const image = new Discord.MassageAttachment(canvas.toBuffer(), 'earthquake.png');

            //Draw earthquake epicenter on canvas
            const epicenter = data[0].epicenter;
            context.beginPath();
            context.arc(epicenter.x, epicenter.y,5, 0, 2 * Math.PI);
            context.fillStyle = '#ff0000';
            context.fill();

            //Initialize voice client
            const voiceClient = new Discord.VoiceConnection(client.guilds.cache.first().client, {selfDeaf: true});

            //Initialize voice channel
            let voiceChannel;

            //Listen for massage event
            client.on('message', massage => {
                if(messageLink.content.startsWith('!setchannel')){
                    //Get voixe channel from massage
                    const channelName = massage.content.slice(12);
                    voiceChannel = message.guild.channels.cache.find(channel => channel.name === channelName && ChannelType === 'voice');
                    if(!voiceChannel){
                        massage.reply('Voice channel ${channelName} not found.');
                    }else{
                        massage.reply('Voice channel ${channelName} set.');
                    }
                }
            });

            //Function to play emergency sound
            async function playEmergencySound(){
                try{
                    //Join voice channel
                    await voiceClient.connect();
                    await voiceChannel.join();

                    //Play emergency sound 3 times
                    for(let i = 0; i < 3; i++){
                        const dispatcher = voiceChannel.play('emergency.mp3');
                        await new Promise(resolve => dispatcher.on('finish', resolve));
                    }

                    //Disconnect from voice channel
                    voiceChannel.leave();
                    voiceClient.disconnect();
                }catch(error){
                    console.error(error);
                }
            }
            
            //Check for earthquakes with intensity 4 or higher
            if(data[0].maxIntensity >= 4){
                //Play emergency sound
                if(voiceChannel){
                    playEmergencySound();
                }else{
                    console.log('Voice channel not set.')
                }
            }

            //Send massage and image to Discord
            const webhook = new Discord.WebhookClient({ url: webhookUrl });
            webhook.send(massage, {files: [image] });

            //Check if the earthquake has an intensity of 4 or higher
            if(data[0].maxIntensity >= 4){
                const tunamiQarningMessage = '津波から身を守るため、海岸または川のそばから離れてください'
                webhook.send('@everyone' + tunamiQarningMessage);
            }
        }
    });
}, 500);

//Log in to Discord
client.login('BOT_TOKEN'); //Replase with your bot token```