How do I take points? I only have a give

How do I add the ability to take points rather than just give?

client.on('ready', () => {
  console.log(`Logged in as ${client.user.tag}!`);
});

fs.readFile(__dirname + "/auth.txt", function(err, buff) {
	if(err && err.code !== 'EEXIST') {
		console.log(err);
	} else client.login(buff.toString())
});

fs.mkdir(__dirname + USER_DIR, function(err) {
	if(err && err.code !== 'EEXIST') {
		console.log(err);
	}
});

client.on('message', msg => {
  if (msg.content.startsWith("!s")) {
    var contents = msg.content.split(" ");
	if(typeof contents[1] == 'undefined') {
		msg.reply(CMD_HELP_ALL);
		msg.reply("debug1");
	} else {
		if(equalsIgnoreCase(contents[1], "give")) {
			if(!msg.member.hasPermission("MANAGE ROLES")) return;
			var ARGS_CHECK_VALIDITY = 3;
			for(var i = 0; i <= ARGS_CHECK_VALIDITY; i++) {
				var arrayIndex = (i + 1), arg = contents[arrayIndex];
				if(!arg || !arg.trim()) {
					bundleMessages(msg, [TOO_FEW_ARGS, CMD_HELP_ALL]);
					return;
				}
			}
			var tagged = msg.mentions.users;
			if(tagged.size != 1) {
				bundleMessages(msg, ["You silly Giga you must tag one user!", CMD_HELP_ALL]);
				return;
			}
			if(isNaN(contents[3])) {
				msg.reply("Gigawatt needs a real number! :(");
				return;
			}
			var points = contents[3];
			/* shift first 4 args */
			var SHIFT_ARGS = 3;
			for(var i = 0; i <= SHIFT_ARGS; i++) {
				contents.shift();
			}
			addPoint(tagged.get(tagged.firstKey()).tag, points, contents.join(" "));
		} else if(equalsIgnoreCase(contents[1], "list")) {
			msg.reply("Fetching data...");
			var membersCollection = msg.guild.members;
			var stringBuilder = SCOREBOARD_PREFIX;
			var map = new Map();
			membersCollection.forEach(function(member) {
				filePath = __dirname + USER_DIR + member.user.tag + ".json";
				if(!fs.existsSync(filePath)) {
					return;
				}
				fs.readFile(filePath, 'utf8', function callback(err, data) {
					if(err) {
						console.log(err);
					} else {
						dataFromJSON = JSON.parse(data);
						var total = 0;
						for(var date in dataFromJSON) {
							var pts = Number.parseInt(dataFromJSON[date].pts);
							total += pts;
						}
						map.set(member.user.tag, total);
					}
				});
			});
			setTimeout(function callback() {
				let sortMap = new Map([...map].sort(([user, pts], [user2, pts2]) => {
					if(pts < pts2) {
						return 1;
					} else if(pts > pts2) {
						return -1;
					} else return 0;
				}));
				let place = 1;
				sortMap.forEach(function callback(value, key) {
					stringBuilder += (place + ". **" + key.substring(0, (key.length - 5)) + "** - " + value.toString() + "\n");
					place++;
				});
				msg.reply(stringBuilder);
			}, 1000);
		} else if(equalsIgnoreCase(contents[1], "log")) {
			if(typeof contents[2] === 'undefined') {
				bundleMessages(msg, [TOO_FEW_ARGS, CMD_HELP_ALL]);
				return;
			}
			var tagged = msg.mentions.users;
			if(tagged.size != 1) {
				bundleMessages(msg, ["You silly Giga, you must tag one user!", CMD_HELP_ALL]);
				return;
			}
			var username = tagged.get(tagged.firstKey()).tag;
			filePath = __dirname + USER_DIR + username + ".json";
			if(!fs.existsSync(filePath)) {
				msg.reply("User has not recieved any spotlights! :o");
				return;
			}
			fs.readFile(filePath, 'utf8', function callback(err, data) {
				if(err) {
					console.log(err);
				} else {
					dataFromJSON = JSON.parse(data);
					var stringBuilder = POINTS_LOG_PREFIX;
					var total = 0;
					for(var date in dataFromJSON) {
						var d = new Date(date);
						var reason = dataFromJSON[date].reason, pts = Number.parseInt(dataFromJSON[date].pts);
						total += pts;
						stringBuilder += ( "*[" + d.toString() + "] Points: " + pts + " - Reason: " + reason + "*\n")
					}
					stringBuilder = stringBuilder.substr(0, (stringBuilder.length - 1)); //snip the break
					stringBuilder = stringBuilder.replace(new RegExp("%user%", 'g'), username);
					stringBuilder = stringBuilder.replace(new RegExp("%pts%", 'g'), total);
					msg.reply(stringBuilder);
				}
			});
		} else {
			bundleMessages(msg, {UNKNOWN_CMD, CMD_HELP_ALL});
		}
	}
  }
});

function bundleMessages(msg, array) {
	for(i = 0; i <= (array.length - 1); i++) {
		msg.reply(array[i]);
	}
}

function equalsIgnoreCase(a, b) {
    return a.toUpperCase() === b.toUpperCase();
}

function addPoint(username, amt, reason) {
	console.log("calling");
	var date = new Date();
	filePath = __dirname + USER_DIR + username + ".json";
	var passedData = {"pts":amt, "reason":reason};
	if(!fs.existsSync(filePath)) {
		var obj = {};
		obj[date.toJSON()] = passedData;
		fs.writeFile(filePath, JSON.stringify(obj, null, 4), function(err) {
			if(err) {
				console.log(err)
			}
		});
	} else {
		fs.readFile(filePath, 'utf8', function callback(err, data) {
			if(err) {
				console.log(err);
			} else {
				dataFromJSON = JSON.parse(data);
				dataFromJSON[date.toJSON()] = passedData;
				writableJSON = JSON.stringify(dataFromJSON, null, 4);
				fs.writeFile(filePath, writableJSON, function(err) {
					if(err) {
						console.log(err);
					}
				});
			}
		});
	}
}

Why don’t you take a shot at writing a method which would do what want? If you get stuck you would need to post the code you tried and then explain in detail all the thing you are expecting the code to do.