fix: NCWF-2 bugs and desing fixes (#7)

Co-authored-by: Lala, Shahd <Shahd.Lala@sybit.de>
Reviewed-on: #7

src/app/services/stream-handler.service.ts

@@ -2,26 +2,14 @@ import { Injectable } from '@angular/core';
 import { Observable } from 'rxjs';
 import { GameStreamEvent, ErrorEvent } from '../models/game.models';
 
+const WS_CONNECT_TIMEOUT_MS = 3000;
+
 @Injectable({ providedIn: 'root' })
 export class StreamHandlerService {
-  createGameStream(wsUrl: string, fallbackUrl: string, gameId: string): Observable<GameStreamEvent> {
+  createGameStream(wsUrl: string, gameId: string): Observable<GameStreamEvent> {
     return new Observable<GameStreamEvent>((observer) => {
       const ws = new WebSocket(wsUrl);
-      const abortController = new AbortController();
       let connected = false;
-      let fallbackActive = false;
-
-      const parseEvent = (raw: string): GameStreamEvent | null => {
-        if (!raw.trim()) {
-          return null;
-        }
-
-        try {
-          return JSON.parse(raw) as GameStreamEvent;
-        } catch {
-          return null;
-        }
-      };
 
       const emitErrorEvent = (message: string): void => {
         const errorEvent: ErrorEvent = {
@@ -31,67 +19,18 @@ export class StreamHandlerService {
         observer.next(errorEvent);
       };
 
-      const startNdjsonFallback = async (): Promise<void> => {
-        if (fallbackActive) {
-          return;
-        }
-
-        fallbackActive = true;
-        console.log(`[StreamHandler] NDJSON fallback started for ${gameId}, URL:`, fallbackUrl);
-
-        try {
-          const response = await fetch(fallbackUrl, {
-            headers: { Accept: 'application/x-ndjson' },
-            signal: abortController.signal
-          });
-
-          if (!response.ok || !response.body) {
-            console.error(`[StreamHandler] NDJSON fetch failed: HTTP ${response.status}`);
-            emitErrorEvent(`Unable to open stream: HTTP ${response.status}`);
-            observer.complete();
-            return;
-          }
-
-          console.log(`[StreamHandler] NDJSON stream connected for ${gameId}`);
-          const reader = response.body.getReader();
-          const decoder = new TextDecoder();
-          let buffer = '';
-
-          while (true) {
-            const { value, done } = await reader.read();
-            if (done) {
-              break;
-            }
-
-            buffer += decoder.decode(value, { stream: true });
-            const lines = buffer.split('\n');
-            buffer = lines.pop() ?? '';
-
-            for (const line of lines) {
-              const event = parseEvent(line);
-              if (event) {
-                observer.next(event);
-              }
-            }
-          }
-
-          observer.complete();
-        } catch (error) {
-          if ((error as Error).name !== 'AbortError') {
-            emitErrorEvent((error as Error).message);
-            observer.error(error);
-          }
-        }
+      const failAndComplete = (reason: string): void => {
+        console.warn(`[StreamHandler] WebSocket failed for ${gameId}: ${reason}`);
+        emitErrorEvent(reason);
+        observer.complete();
       };
 
-      // Set timeout to fallback if WebSocket doesn't connect quickly
       const connectionTimeoutId = setTimeout(() => {
-        if (!connected && !fallbackActive) {
-          console.warn(`[StreamHandler] WebSocket timeout for ${gameId}, attempting NDJSON fallback`);
+        if (!connected) {
           ws.close();
-          void startNdjsonFallback();
+          failAndComplete('WebSocket connection timed out — falling back to polling');
         }
-      }, 3000);
+      }, WS_CONNECT_TIMEOUT_MS);
 
       ws.onopen = () => {
         connected = true;
@@ -101,35 +40,30 @@ export class StreamHandlerService {
 
       ws.onmessage = (message) => {
         const payload = typeof message.data === 'string' ? message.data : '';
-        const event = parseEvent(payload);
-        if (event) {
+        if (!payload.trim()) return;
+        try {
+          const event = JSON.parse(payload) as GameStreamEvent;
           observer.next(event);
+        } catch {
+          // ignore malformed frames
         }
       };
 
-      ws.onerror = (error) => {
-        console.warn(`[StreamHandler] WebSocket error for ${gameId}:`, error);
+      ws.onerror = () => {
         clearTimeout(connectionTimeoutId);
-        if (!connected && !fallbackActive) {
-          void startNdjsonFallback();
+        if (!connected) {
+          failAndComplete('WebSocket connection error — falling back to polling');
         }
       };
 
       ws.onclose = () => {
         clearTimeout(connectionTimeoutId);
-        console.warn(`[StreamHandler] WebSocket closed for ${gameId}, connected=${connected}`);
         if (connected) {
-          // Connection was established but closed, stream is complete
           observer.complete();
-        } else if (!fallbackActive) {
-          // Connection never established, try fallback
-          console.log(`[StreamHandler] Starting NDJSON fallback for ${gameId}`);
-          void startNdjsonFallback();
         }
       };
 
       return () => {
-        abortController.abort();
         ws.close();
       };
     });