cleaning up joinGroup and createGroup functions

src/game/game.service.ts

 import { Injectable, HttpException, HttpStatus } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
-import { Repository, Not, In } from 'typeorm';
+import { Repository, Not } from 'typeorm';
 
-import { GameEntity, FactionEntity, Game_PersonEntity } from './game.entity';
+import { GameEntity, Game_PersonEntity } from './game.entity';
 import { GameDTO } from './game.dto';
 import { PersonEntity } from '../user/user.entity';
 import { GameGroupEntity } from './group.entity';
+import { FactionEntity } from './faction.entity';
 
 @Injectable()
 export class GameService {
@@ -68,10 +69,10 @@ export class GameService {
 
     // get all the factions that are associated with the game to deny duplicate entries
     const factions = await this.factionRepository.find({
-      select: ['name'],
+      select: ['factionName'],
       where: { game: gameId },
     });
-    const factionNames = factions.map(({ name }) => name);
+    const factionNames = factions.map(({ factionName }) => factionName);
 
     // add the factions to db
     if (gameData.factions) {
@@ -94,34 +95,37 @@ export class GameService {
   // checks the password, creates an entry in GamePerson table with associated role&faction
   async createGroup(person, gameId, groupData) {
     try {
-      // create a partial game_Person entry and insert it to db
-      const gamePerson = await this.game_PersonRepository.create({
-        role: 'soldier',
-        faction: null,
-        game: gameId,
+      // check if the person already is in a group in this game
+      const checkDuplicate = await this.game_PersonRepository.findOne({
         person: person,
-        leaderGroup: null,
-        group: null,
       });
-      const gamePersonId = await this.game_PersonRepository.insert(gamePerson);
+      if (checkDuplicate) {
+        throw new HttpException(
+          'You already belong to a group!',
+          HttpStatus.BAD_REQUEST,
+        );
+      }
 
       // create a group entry and insert it to db
       const group = await this.game_GroupRepository.create({
         ...groupData,
-        leader: gamePerson.gamepersonId,
-        players: gamePerson.gamepersonId,
         game: gameId,
       });
       const gameGroup = await this.game_GroupRepository.insert(group);
 
-      // add the missing information to game_Person and update the db entry
-      gamePerson['gamepersonId'] = gamePersonId.identifiers[0]['gamepersonId'];
-      gamePerson['leaderGroup'] = gameGroup.identifiers[0]['id'];
-      gamePerson['group'] = gameGroup.identifiers[0]['id'];
-      await this.game_PersonRepository.save(gamePerson);
+      // create game_Person entry and insert it to db
+      const gamePerson = await this.game_PersonRepository.create({
+        role: 'soldier',
+        faction: null,
+        game: gameId,
+        person: person,
+        leaderGroup: gameGroup.identifiers[0]['id'],
+        group: gameGroup.identifiers[0]['id'],
+      });
+      await this.game_PersonRepository.insert(gamePerson);
 
       return {
-        "message": "created new group"
+        message: 'created new group',
       };
     } catch (e) {
       return e;
@@ -140,45 +144,25 @@ export class GameService {
 
   async joinGroup(person, groupId) {
     try {
-      // get the old group data to see earlier players
-      const oldData = await this.game_GroupRepository.findOne({
+      const gameData = await this.game_GroupRepository.findOne({
         where: { id: groupId },
         relations: ['players', 'game'],
       });
-      // create game_Person entry for the joining player and insert it
       const gamePerson = await this.game_PersonRepository.create({
         role: 'soldier',
         faction: null,
-        game: oldData.game,
+        game: gameData.game,
         person: person,
         leaderGroup: null,
-        group: null,
+        group: groupId,
       });
-      console.log(oldData)
-      console.log(gamePerson)
-      const gamePersonId = await this.game_PersonRepository.insert(gamePerson);
-      // map the players from old data to array and push the new one
-      const oldPlayers = oldData.players.map(
-        ({ gamepersonId }) => gamepersonId,
-        );
-        oldPlayers.push(person);
-        // string[] to Game_PersonEntity[]
-        const newPlayers = await this.game_PersonRepository.find({gamepersonId: In(oldPlayers)})
-        // create group entity and update the entry in db
-        const group = await this.game_GroupRepository.create({
-          id: groupId,
-          players: newPlayers,
-        });
-        const gameGroup = await this.game_GroupRepository.save(group);
-        // add the missing information to game_Person and update the db entry
-        gamePerson['gamepersonId'] = gamePersonId.identifiers[0]['gamepersonId'];
-        gamePerson['leaderGroup'] = gameGroup;
-        gamePerson['group'] = gameGroup;
-        await this.game_PersonRepository.save(gamePerson);
-        return {
-          "message" : "Joined group"
-        }
-    } catch(e) {return e}
+      await this.game_PersonRepository.insert(gamePerson);
+      return {
+        message: 'Joined group',
+      };
+    } catch (e) {
+      return e;
+    }
   }
 
   // returns name and id of each game