feat: implement core BlackStream platform functionality

Co-authored-by: blackboxprogramming <118287761+blackboxprogramming@users.noreply.github.com>

backend/sync-service/index.js

@@ -0,0 +1,67 @@
+const express = require('express');
+const cors = require('cors');
+const app = express();
+const port = process.env.PORT || 4003;
+
+app.use(cors());
+app.use(express.json());
+
+// In-memory watch progress store keyed by userId (replace with a real database in production)
+// Structure: { [userId]: { [contentId]: { progressSeconds, durationSeconds, updatedAt } } }
+const progress = new Map();
+
+app.get('/', (req, res) => {
+  res.json({ service: 'BlackStream Sync Service', status: 'ok', version: '0.1.0' });
+});
+
+// Save or update watch progress for a user
+app.post('/progress/:userId/:contentId', (req, res) => {
+  const { userId, contentId } = req.params;
+  const { progressSeconds, durationSeconds } = req.body;
+
+  if (progressSeconds === undefined || durationSeconds === undefined) {
+    return res.status(400).json({ error: 'progressSeconds and durationSeconds are required' });
+  }
+
+  if (!progress.has(userId)) {
+    progress.set(userId, new Map());
+  }
+
+  progress.get(userId).set(contentId, {
+    contentId,
+    progressSeconds: Number(progressSeconds),
+    durationSeconds: Number(durationSeconds),
+    updatedAt: new Date().toISOString(),
+  });
+
+  res.json({ userId, contentId, progressSeconds, durationSeconds });
+});
+
+// Get all watch progress for a user
+app.get('/progress/:userId', (req, res) => {
+  const { userId } = req.params;
+  const userProgress = progress.get(userId);
+
+  if (!userProgress) {
+    return res.json({ userId, progress: [] });
+  }
+
+  res.json({ userId, progress: Array.from(userProgress.values()) });
+});
+
+// Get watch progress for a specific title
+app.get('/progress/:userId/:contentId', (req, res) => {
+  const { userId, contentId } = req.params;
+  const userProgress = progress.get(userId);
+  const item = userProgress && userProgress.get(contentId);
+
+  if (!item) {
+    return res.status(404).json({ error: 'No progress found for this title' });
+  }
+
+  res.json({ userId, ...item });
+});
+
+app.listen(port, () => {
+  console.log(`Sync Service listening on port ${port}`);
+});