import express, { Express } from "express";
import { ServerMessages } from "../route/messages";
import { Route } from "../route/route";

type ServerConfig = {
  port: number;
  routes?: Route[];
};

export default class Server {
  /**
   * The port that this server is listening on.
   */
  private port: number;

  /**
   * The express server.
   */
  private server: Express;

  /**
   * The routes that this server is serving.
   */
  private routes: Route[] = [];

  constructor({ port, routes }: ServerConfig) {
    this.port = port;
    if (routes) {
      this.routes.push(...routes);
    }

    // Create the express server
    this.server = express();
    this.preInit();

    // Setup route logging
    this.server.use((req, res, next) => {
      // TODO: make this look better?
      console.log(`[${req.method}] ${req.path}`);
      next();
    });

    // Handle the routes
    for (const route of this.routes) {
      this.server.all(route.getPath(), (req, res, next) => {
        if (req.method.toUpperCase() !== route.getMethod().toUpperCase()) {
          return next(); // Skip this method
        }
        try {
          route.handle(req, res, next);
        } catch (ex) {
          console.error(ex);
          // Inform the user that an internal server error occurred
          res.status(500).json(ServerMessages.internalServerError());
        }
      });
    }

    // Log the registered routes
    console.log(`Registered ${this.routes.length} routes`);
    for (const route of this.routes) {
      console.log(`  - ${route.getMethod().toUpperCase()} ${route.getPath()}`);
    }

    // Handle unknown routes
    this.server.all("*", (req, res) => {
      res.status(404).send("404 Not Found");
    });

    // Start listening on the specified port
    this.server.listen(this.port, () => {
      console.log(`Server listening on http://localhost:${this.port}`);
      this.postInit();
    });
  }

  /**
   * Returns the port that this server is listening on.
   *
   * @returns {number} the port
   */
  public getPort() {
    return this.port;
  }

  /**
   * Registers a list of routes.
   *
   * @param route the routes to register
   */
  public registerRoute(...routes: Route[]) {
    this.routes.push(...routes);
  }

  public getRoute(path: string): Route | undefined {
    return this.routes.find((route) => route.getPath() === path);
  }

  /**
   * Gets called before the server starts listening.
   */
  public preInit(): void {}

  /**
   * Gets called after the server starts listening.
   */
  public postInit(): void {}
}