import { Injectable } from '@nestjs/common';
import { ServerStatusDto } from './server-status.dto';
import { promises as fs } from 'fs';
import { join as joinPath } from 'path';

let versionCache: null | {
  major: number;
  minor: number;
  patch: number;
  preRelease?: string;
  commit?: string;
} = null;
async function getServerVersionFromPackageJson() {
  if (versionCache === null) {
    const rawFileContent: string = await fs.readFile(
      joinPath(__dirname, '../../package.json'),
      { encoding: 'utf8' },
    );
    const packageInfo: { version: string } = JSON.parse(rawFileContent);
    const versionParts: number[] = packageInfo.version
      .split('.')
      .map((x) => parseInt(x, 10));
    versionCache = {
      major: versionParts[0],
      minor: versionParts[1],
      patch: versionParts[2],
      preRelease: 'dev', // TODO: Replace this?
    };
  }

  return versionCache;
}

@Injectable()
export class MonitoringService {
  async getServerStatus(): Promise<ServerStatusDto> {
    return {
      connectionSocketQueueLenght: 0,
      destictOnlineUsers: 0,
      disconnectSocketQueueLength: 0,
      distictOnlineRegisteredUsers: 0,
      isConnectionBusy: false,
      isDisconnectBusy: false,
      notesCount: 0,
      onlineNotes: 0,
      onlineRegisteredUsers: 0,
      onlineUsers: 0,
      registeredUsers: 0,
      serverVersion: await getServerVersionFromPackageJson(),
    };
  }
}