server.js

require("dotenv").config();
const express = require("express");
const cors = require("cors");
const axios = require("axios");

const app = express();
app.use(express.json());
app.use(cors()); // Allow frontend to access the backend

const API_URL = "https://api-inference.huggingface.co/models/cardiffnlp/twitter-roberta-base-sentiment";
const API_KEY = process.env.HUGGINGFACE_API_KEY;

app.post("/analyze", async (req, res) => {
    const { text } = req.body;

    if (!text || text.trim() === "") {
        return res.status(400).json({ error: "Text input cannot be empty." });
    }

    try {
        const response = await axios.post(
            API_URL,
            { inputs: text },
            { headers: { Authorization: `Bearer ${API_KEY}` } }
        );

        if (!Array.isArray(response.data) || response.data.length === 0) {
            throw new Error("Invalid API response.");
        }

        // Extract the sentiment label with the highest probability
        const emotions = response.data[0];
        const topEmotion = emotions.reduce((max, obj) => (obj.score > max.score ? obj : max), emotions[0]);

        res.json({ label: topEmotion.label, score: topEmotion.score });
    } catch (error) {
        console.error("Error:", error.response ? error.response.data : error.message);
        res.status(500).json({ error: "Failed to analyze sentiment. Please try again later." });
    }
});

const PORT = process.env.PORT || 5000;
app.listen(PORT, () => console.log(`✅ Server running on port ${PORT}`));