main.js

const express = require("express");
const axios = require("axios");
const dotenv = require("dotenv");

dotenv.config();

const app = express();
const port = process.env.PORT || 3000;

const CLIENT_ID = process.env.GITHUB_CLIENT_ID;
const CLIENT_SECRET = process.env.GITHUB_CLIENT_SECRET;
const REDIRECT_URI = process.env.GITHUB_REDIRECT_URI;

// Step 1: Redirect user to GitHub for authentication
app.get("/auth/github", (req, res) => {
  const githubAuthUrl = `https://github.com/login/oauth/authorize?client_id=${CLIENT_ID}&redirect_uri=${REDIRECT_URI}`;
  res.redirect(githubAuthUrl);
});


  try {
    // Step 3: Exchange the authorization code for an access token
    const response = await axios.post(
      "https://github.com/login/oauth/access_token",
      {
        client_id: CLIENT_ID,
        client_secret: CLIENT_SECRET,
        code,
        redirect_uri: REDIRECT_URI,
      },
      {
        headers: {
          Accept: "application/json",
        },
      }
    );

    const accessToken = response.data.access_token;

    // Step 4: Use the access token to fetch user data
    const userResponse = await axios.get("https://api.github.com/user", {
      headers: {
        Authorization: `Bearer ${accessToken}`,
      },
    });

    res.json({
      user: userResponse.data,
      access_token: accessToken,
    });
  } catch (error) {
    console.error("Error exchanging code for token:", error);
    res.status(500).send("Error authenticating with GitHub");
  }
});

app.listen(port, () => {
  console.log(`Server running at http://localhost:${port}`);
});