const express = require('express');
const multer = require('multer');
const { google } = require('googleapis');
const fs = require('fs');
const path = require('path');

const app = express();

// Konfigurasi multer untuk menangani upload file
const upload = multer({ dest: 'uploads/' });

// Setup Google Drive API credentials
const CLIENT_ID = process.env.GOOGLE_DRIVE_CLIENT_ID;
const CLIENT_SECRET = process.env.GOOGLE_DRIVE_CLIENT_SECRET;
const REFRESH_TOKEN = process.env.GOOGLE_DRIVE_REFRESH_TOKEN;
const FOLDER_ID = process.env.GOOGLE_DRIVE_FOLDER_ID;

const oauth2Client = new google.auth.OAuth2(
  CLIENT_ID,
  CLIENT_SECRET,
  "https://developers.google.com/oauthplayground" // Redirect URL (tidak digunakan)
);

oauth2Client.setCredentials({
  refresh_token: REFRESH_TOKEN,
});

const drive = google.drive({
  version: 'v3',
  auth: oauth2Client,
});

// Function to upload file to Google Drive
async function uploadFileToGoogleDrive(file) {
  try {
    const fileMetadata = {
      'name': file.originalname,
      'parents': [FOLDER_ID], // Folder ID tempat file akan disimpan
    };

    const media = {
      mimeType: file.mimetype,
      body: fs.createReadStream(file.path),
    };

    const response = await drive.files.create({
      resource: fileMetadata,
      media: media,
      fields: 'id',
    });

    return response.data.id;
  } catch (error) {
    throw new Error('Gagal mengunggah ke Google Drive: ' + error.message);
  }
}

// Endpoint untuk upload file
app.post('/upload', upload.single('file'), async (req, res) => {
  try {
    if (!req.file) {
      return res.status(400).send('No file uploaded.');
    }

    const fileId = await uploadFileToGoogleDrive(req.file);

    // Hapus file lokal setelah diunggah ke Google Drive
    fs.unlinkSync(req.file.path);

    res.json({
      message: 'File uploaded successfully to Google Drive!',
      fileId: fileId,
    });
  } catch (error) {
    res.status(500).send('Error uploading file: ' + error.message);
  }
});

// Start server
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`Server running on port ${PORT}`);
});