import React from 'react';
import { NavigationContainer } from '@react-navigation/native';
import { createStackNavigator } from '@react-navigation/stack';
import HomeScreen from './screens/HomeScreen';
import LoginScreen from './screens/LoginScreen';

const Stack = createStackNavigator();

export default function App() {
  return (
    <NavigationContainer>
      <Stack.Navigator initialRouteName="Login">
        <Stack.Screen name="Login" component={LoginScreen} />
        <Stack.Screen name="Home" component={HomeScreen} />
      </Stack.Navigator>
    </NavigationContainer>
  );
}
import React, { useEffect, useState } from 'react';
import { View, FlatList, Text } from 'react-native';
import axios from 'axios';

export default function HomeScreen() {
  const [posts, setPosts] = useState([]);

  useEffect(() => {
    axios.get('http://localhost:3000/posts')  // Backend API
      .then(response => setPosts(response.data))
      .catch(error => console.error(error));
  }, []);

  const renderPost = ({ item }) => (
    <View style={{ padding: 10 }}>
      <Text>{item.caption}</Text>
      {/* Add image/video display here */}
    </View>
  );

  return (
    <FlatList
      data={posts}
      renderItem={renderPost}
      keyExtractor={item => item.id}
    />
  );
}import React, { useState } from 'react';
import { View, TextInput, Button } from 'react-native';
import axios from 'axios';

export default function CreatePostScreen() {
  const [caption, setCaption] = useState('');

  const handlePost = () => {
    axios.post('http://localhost:3000/posts', { caption, userId: 'user123' })
      .then(() => alert('Post created!'))
      .catch(error => console.error(error));
  };

  return (
    <View>
      <TextInput placeholder="Caption" value={caption} onChangeText={setCaption} />
      <Button title="Post" onPress={handlePost} />
    </View>
  );
}const express = require('express');
const mongoose = require('mongoose');
const cors = require('cors');
const postRoutes = require('./routes/posts');

const app = express();
app.use(cors());
app.use(express.json());

mongoose.connect('mongodb://localhost:27017/nexy', { useNewUrlParser: true });

app.use('/posts', postRoutes);

app.listen(3000, () => console.log('Server running on port 3000'));
const mongoose = require('mongoose');

const postSchema = new mongoose.Schema({
  userId: String,
  caption: String,
  imageUrl: String,
  likes: { type: Number, default: 0 },
  createdAt: { type: Date, default: Date.now }
});

module.exports = mongoose.model('Post', postSchema);
const express = require('express');
const Post = require('../models/Post');

const router = express.Router();

// Get all posts (for feed)
router.get('/', async (req, res) => {
  const posts = await Post.find().sort({ createdAt: -1 });
  res.json(posts);
});

// Create post
router.post('/', async (req, res) => {
  const newPost = new Post(req.body);
  await newPost.save();
  res.json(newPost);
});

module.exports = router;
import pandas as pd
from sklearn.metrics.pairwise import cosine_similarity

# Sample data: user interactions (likes, etc.)
data = {
    'user': ['user1', 'user1', 'user2'],
    'post': ['post1', 'post2', 'post1'],
    'score': [1, 0.5, 1]  # Engagement score
}
df = pd.DataFrame(data)

# Pivot to user-post matrix
matrix = df.pivot_table(index='user', columns='post', values='score', fill_value=0)

# Compute similarity
similarity = cosine_similarity(matrix)

# Recommend for user1: Find similar posts
def recommend(user, matrix, similarity):
    user_index = matrix.index.get_loc(user)
    similar_users = similarity[user_index]
    # Aggregate scores from similar users (simplified)
    recommendations = matrix.T.dot(similar_users) / similar_users.sum()
    return recommendations.sort_values(ascending=False)

print(recommend('user1', matrix, similarity))
import React, { useEffect, useState } from 'react';
import axios from 'axios';

export default function AdminDashboard() {
  const [posts, setPosts] = useState([]);

  useEffect(() => {
    axios.get('http://localhost:3000/admin/posts')  // Protected endpoint
      .then(response => setPosts(response.data));
  }, []);

  const deletePost = (id) => {
    axios.delete(`http://localhost:3000/admin/posts/${id}`);
    setPosts(posts.filter(p => p.id !== id));
  };

  return (
    <div>
      {posts.map(post => (
        <div key={post.id}>
          <p>{post.caption}</p>
          <button onClick={() => deletePost(post.id)}>Delete</button>
        </div>
      ))}
    </div>
  );
}