import type {TypedArray, ReadableStream} from "@encore.dev/internal-runtime/compat/types";

/**
 * HTTP methods
 */
export enum Method {
  GET = "GET",
  HEAD = "HEAD",
  POST = "POST",
  PUT = "PUT",
  DELETE = "DELETE",
  CONNECT = "CONNECT",
  OPTIONS = "OPTIONS",
  TRACE = "TRACE",
  PATCH = "PATCH",

  /**
   * Represents any HTTP method
   */
  Any = "*",
}

export enum StatusCode {
  OK = 200,
  NOT_FOUND = 404,
  INTERNAL = 500,
}

/**
 * Represents a raw HTTP request
 */
export interface Request {
  /**
   * The HTTP method of the request
   */
  method: Method;

  /**
   * The URL of the request
   */
  url: URL;

  /**
   * Header returns the values specified for the given header
   * or an empty array if the header is not present.
   *
   * Note: only "Set-Cookie" can have multiple values for Bun, all others
   * will only have a single value if present.
   */
  header(name: string): string[];

  /**
   * The request body of the request or null if not present
   */
  body: ReadableStream<Uint8Array> | null;

  /**
   * The request body, parsed as JSON.
   * Returns null if there is no body.
   */
  json(): Promise<unknown | null>;
}

/**
 * Represents a raw HTTP response.
 *
 * The response *must* be closed after it is done being written to.
 */
export interface Response {
  /**
   * Appends a header to the response
   *
   * @throws {ResponseStartedError} If the response stream has started
   */
  appendHeader(name: string, value: string): void;

  /**
   * Set the HTTP status code of the response
   *
   * Can only be set before the first write, if not called
   * before the first write, the status will be 200
   *
   * @throws {ResponseStartedError} If the response stream has started
   */
  status(code: StatusCode): void;

  /**
   * Writes a header to the response
   *
   * @throws {ResponseClosedError} If the response has has been closed
   */
  write(data: TypedArray | DataView | ArrayBufferLike | string): Promise<void>;

  /**
   * Flushes the response
   *
   * @throws {ResponseClosedError} If the response has has been closed
   */
  flush(): Promise<void>;

  /**
   * Closes the response
   */
  close(): Promise<void>;
}

/**
 * An API route as defined by the Encore application
 */
export interface ApiRoute {
  service: string; // The service the route is registered in
  name: string; // The name of the API endpoint
  methods: [Method, ...Method[]]; // The HTTP method(s) of the route
  path: string; // The path to the route
  handler: (req: Request, res: Response, params: string[]) => Promise<void>; // The handler for the route
}