import express, { Express } from 'express';

import { HttpStatusException } from '../../common/lib/http-status.exception';
import { Logger } from '../../common/util/logger.class';

import { Database } from './database.class';

export class Webserver {
  private app: Express;

  constructor(private port: number, private db: Database) {
    this.app = express();

    this.app.get('/server', async (req, res, next) => {
      try {
        const serverConfigs = await this.db.getAllServerConfigs();
        res.send(serverConfigs);
      } catch (err) {
        next(err);
      }
    });

    this.app.get('/server/:serverID/data/types', async (req, res, next) => {
      try {
        const serverID = Number(req.params.serverID);

        if (Number.isNaN(serverID)) {
          throw new HttpStatusException(`Not a valid server id: ${req.params.serverID}`, 400);
        }

        const serverDataTypes = await this.db.getServerDataTypes(serverID);
        res.send(serverDataTypes);
      } catch (err) {
        next(err);
      }
    });

    this.app.get('/server/:serverID/data', async (req, res, next) => {
      try {
        const serverID = Number(req.params.serverID);

        if (Number.isNaN(serverID)) {
          throw new HttpStatusException(`Not a valid server id: ${req.params.serverID}`, 400);
        }

        const qStart = (req.query.start || '').toString();
        const qEnd = (req.query.end || '').toString();
        const qType = (req.query.type || '').toString();

        if (!qStart || !qEnd || !qType) throw new HttpStatusException("QueryParams 'type', 'start' and 'end' are mandatory.", 400);

        const start = new Date(qStart);
        const end = new Date(qEnd);
        if ([start.toString(), end.toString()].includes('Invalid Date')) {
          throw new HttpStatusException("QueryParams 'start' and 'end' must be parseable dates or unix epoch timestamps (ms).", 400);
        }

        const data = await this.db.queryServerData(serverID, qType, start, end);
        res.send({
          start,
          end,
          data
        } as QueryResponse<ServerData>);
      } catch (err) {
        next(err);
      }
    });

    this.app.use('/', express.static(process.env.STATIC_DIR || 'public'));

    this.app.use((err, req, res, next) => {
      if (err instanceof HttpStatusException) {
        res.status(err.statusCode).send(err.message);
      } else {
        Logger.error('[ERROR] Webservice ErrorHandler caught:', err);
        res.status(500).send(JSON.stringify(err));
      }
    });

    this.app.listen(this.port, () => {
      Logger.info(`[INFO] Monitoring Webserver started at http://localhost:${this.port}`);
    });
  }
}