ksfw.ts

import { extname } from 'https://deno.land/std@0.166.0/path/mod.ts';
import { contentType } from 'https://deno.land/std@0.166.0/media_types/mod.ts';
import { DB } from 'https://deno.land/x/sqlite@v3.7.0/mod.ts';

export class ksfw {

	constructor() {
		this.client_list = [];
		this.db = new DB('./ksfw.db');
		this.db.execute(`
			CREATE TABLE IF NOT EXISTS user (
				user_id INTEGER PRIMARY KEY AUTOINCREMENT,
				user_uuid TEXT UNIQUE
			)
		`);
	}

	get_body(path) {
		if (extname(path) !== '.html') return Deno.readFileSync(path);
		let body = Deno.readTextFileSync(path);
		while (body.match(/<!-- include (\S+) -->/)) {
			body = body.replace(/<!-- include (\S+) -->/g, function () {
				return this.get_body(arguments[1]).trimEnd();
			}.bind(this));
		}
		return body;
	}

	async respond(pathname) {
		if (pathname === 'ksfw.js') {
			let body = '';
			for (const path of ['./ksfw.js']) {
				const url = new URL(path, import.meta.url);
				const res = await fetch(url);
				body += await res.text();
			}
			return new Response(body, {
				headers: {
					'Content-Type': contentType('.js'),
				},
			});
		}
		for (const directory of ['./client', './design/entry_point']) {
			try {
				const body = this.get_body(directory + '/' + pathname);
				return new Response(body, {
					headers: {
						'Content-Type': contentType(extname(pathname)),
					},
				});
			} catch (error) {
			}
		}
		return new Response('Not Found', {
			status: 404,
			headers: {
				'Content-Type': contentType('.html'),
			},
		});
	}

	handler(request) {
		const url = new URL(request.url);
		const pathname = url.pathname === '/' ? 'index.html' : url.pathname.replace(/^\//, '');
		const params = {};
		for (const [key, value] of url.searchParams) {
			params[key] = value;
		}
		if (pathname === 'ws') {
			const { socket, response } = Deno.upgradeWebSocket(request);

			// onopen
			socket.onopen = event => {

				let user;
				let user_uuid = params.user_uuid;
				while (true) {
					user = this.db.prepareQuery('SELECT * FROM user WHERE user_uuid = :user_uuid').firstEntry({
						user_uuid,
					});
					if (user) break;
					user_uuid = crypto.randomUUID()
					this.db.prepareQuery('INSERT INTO user (user_uuid) VALUES (:user_uuid)').execute({
						user_uuid,
					});
				}
				const new_user = JSON.parse(JSON.stringify(user));
				delete new_user.user_uuid;
				this.client_list.push({
					user: new_user,
					socket: event.target,
				});

				console.log('onopen:', 'number of clients:', this.client_list.length);
				const client = this.client_list.find(client => client.socket === event.target);
				socket.send(JSON.stringify({
					pathname: 'connected',
					params: {
						user,
					}
				}));
			};

			// onmessage
			socket.onmessage = event => {
				const client = this.client_list.find(client => client.socket === event.target);
				const data = JSON.parse(event.data);
				this[data.pathname](client, data.params);
			}

			// onclose
			socket.onclose = event => {
				this.client_list = this.client_list.filter(client => client.socket !== event.target);
				console.log('onclose:', 'number of clients:', this.client_list.length);
			}

			// onerror
			socket.onerror = event => {
				console.error('onerror:', event);
			}

			return response;
		}
		else {
			return this.respond(pathname);
		}
	}

	broadcast(pathname, params) {
		for (const client of this.client_list) {
			client.socket.send(JSON.stringify({pathname, params}));
		}
	}
}