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import {  serve,  type ServeInit,} from "https://deno.land/std@0.146.0/http/server.ts";
export type Middleware = (  ctx: Context,  next: NextFunction,) => Promise<unknown> | unknown;
export type NextFunction = (  ctx?: Context,) => Promise<Response>;
export interface Context {  request: Request;  params: Record<string, string>;  assert: (    expr: unknown,    status?: number,    message?: string,    init?: ResponseInit,  ) => asserts expr;}
export interface ContextInit {  request: Request;  params?: Record<string, string>;}
export const createContext = ({  request,  params = {},}: ContextInit): Context => ({  request,  params,  assert(expr, status = 500, message = "Assertion failed.", init) {    if (expr) return;    throw new ServerError(status, message, init);  },});
export class ServerError extends Error {  expose: boolean;  init: ResponseInit;
  constructor(status: number, message?: string, init: ResponseInit = {}) {    super(message ?? "Internal Server Error");    this.init = { status, ...init };    this.expose = status < 500;  }}
const isJSON = (val: unknown) => {  try {    const s = JSON.stringify(val);    JSON.parse(s);    return true;  } catch {    return false;  }};
const decode = (res: unknown) => {  if (res instanceof Response) return res;  if (typeof res === "string") return new Response(res);  if (isJSON(res)) return Response.json(res);  throw new Error("Invalid response");};
const compose = (middlewares: Middleware[]) => {  let ctx: Context;  let cur = -1;  const max = middlewares.length;  let next: NextFunction;  return next = async (c = ctx) =>    ++cur >= max      ? new Response("Not Found", { status: 404 })      : decode(await middlewares[cur](ctx = c, next));};
// deno-lint-ignore no-explicit-anyconst convert = (error: any) => {  let { message, expose = false, init = { status: 500 } } = error;  if (!expose) message = "Internal Server Error";  return Response.json({ message }, init);};
interface Match {  middlewares: Middleware[];  params?: Record<string, string>;}
export interface Application {  get(path: string, ...middlewares: Middleware[]): Application;  post(path: string, ...middlewares: Middleware[]): Application;  put(path: string, ...middlewares: Middleware[]): Application;  patch(path: string, ...middlewares: Middleware[]): Application;  delete(path: string, ...middlewares: Middleware[]): Application;  options(path: string, ...middlewares: Middleware[]): Application;  head(path: string, ...middlewares: Middleware[]): Application;  use(...middlewares: Middleware[]): Application;  handle(request: Request): Promise<Response>;  serve(init?: ServeInit): Promise<void>;}
export class Application {  #patterns: Set<URLPattern>;  #middlewares: Middleware[];  #routes: Record<string, Middleware[]>;  #cache: Record<string, Match | null>;
  constructor() {    this.#patterns = new Set();    this.#middlewares = [];    this.#routes = this.#cache = {};
    // Define methods    // deno-fmt-ignore-line    const methods = ['get', 'post', 'put', 'patch', 'delete', 'options', 'head'] as const;    for (const method of methods) {      this[method] = (path, ...middlewares) =>        this.#add(path, method.toUpperCase(), middlewares);    }  }
  #add(path: string, method: string, middlewares: Middleware[]) {    const id = method + path;    const route = this.#routes[id];    if (route) route.push(...middlewares);    const pattern = new URLPattern({ pathname: path });    this.#patterns.add(pattern);    this.#routes[id] = middlewares;    return this;  }
  #match(url: string, method: string) {    const id = method + url;    const hit = this.#cache[id];    if (hit) return hit;    const pattern = [...this.#patterns].find((p) => p.test(url));    const middlewares = this.#routes[method + pattern?.pathname];    if (!middlewares) return this.#cache[id] = null;    if (pattern?.pathname.includes(":")) {      const exec = pattern.exec(url);      const params = exec?.pathname.groups;      return this.#cache[id] = { middlewares, params };    } else return this.#cache[id] = { middlewares };  }
  use(...middlewares: Middleware[]) {    const at = this.#middlewares.length - 1;    this.#middlewares.splice(at, 0, ...middlewares);    return this;  }
  handle = (request: Request) => {    const match = this.#match(request.url, request.method);    const ctx = createContext({ request, params: match?.params });    const middlewares = match      ? this.#middlewares.concat(match.middlewares)      : this.#middlewares;    return compose(middlewares)(ctx).catch(convert);  };
  serve = (opts?: ServeInit) => serve(this.handle, opts);}
export default () => new Application();