server.js

const express = require("express");
const multer = require("multer");
const axios = require("axios");
const dotenv = require("dotenv");
const path = require("path");
const helmet = require("helmet");
const cors = require("cors");
const FormData = require("form-data");

dotenv.config();

const app = express();

app.use(helmet());

// CORS setup (allows requests)
const allowedOrigins = [
  process.env.FRONT_URL,
  /^http:\/\/localhost:\d+$/, // Accepts any localhost port
];

app.use(
  cors({
    origin: (origin, callback) => {
      // Allow requests with no origin (like mobile apps or curl requests)
      if (!origin) return callback(null, true);

      // Check if origin matches any allowed pattern
      const isAllowed = allowedOrigins.some((allowedOrigin) => {
        if (allowedOrigin instanceof RegExp) {
          return allowedOrigin.test(origin);
        }
        return allowedOrigin === origin;
      });

      if (isAllowed) {
        callback(null, true);
      } else {
        callback(new Error("Not allowed by CORS"));
      }
    },
    methods: "GET,POST",
    allowedHeaders: "Content-Type,Authorization",
  })
);

// Multer setup for file upload
const storage = multer.memoryStorage();
const upload = multer({
  storage: storage,
  limits: { fileSize: 20 * 1024 * 1024 }, // Limiter à 20 Mo
  fileFilter: (req, file, cb) => {
    const allowedMimeTypes = ["image/jpeg", "image/png", "image/gif"];
    if (allowedMimeTypes.includes(file.mimetype)) {
      cb(null, true);
    } else {
      cb(new Error("Invalid file type. Only JPEG, PNG, and GIF are allowed."));
    }
  },
});

// Route for handling image upload
app.post("/upload", upload.single("image"), async (req, res) => {
  console.log("Image received");

  if (!req.file) {
    return res.status(400).json({ message: "No image uploaded" });
  }

  const imageBuffer = req.file.buffer;

  try {
    const form = new FormData();
    form.append("file", imageBuffer, { filename: req.file.originalname });

    const response = await axios.post(
      process.env.FAKE_IMAGE_API_URL + "/predict",
      form,
      {
        headers: {
          ...form.getHeaders(), // Important pour inclure les en-têtes nécessaires pour multipart/form-data
        },
      }
    );

    res.json(response.data);
  } catch (error) {
    console.error("Error processing the image:", error.message);
    res
      .status(500)
      .json({ message: "An error occurred while processing the image." });
  }
});

app.get("/healthcheck", async (req, res) => {
  try {
    const isApiAlive = await axios.get(process.env.FAKE_IMAGE_API_URL + "/");

    if (isApiAlive.status === 200) {
      return res.json({
        status: "ok",
        details: {
          message: "API is running fine",
          fake_image_api_connection: "ok",
        },
      });
    } else {
      return res.status(503).json({
        status: "error",
        details: {
          message: "API is not responding",
          fake_image_api_connection: "error",
        },
      });
    }
  } catch (error) {
    // En cas d'erreur de connexion
    return res.status(503).json({
      status: "error",
      details: {
        message: "API is not responding",
        fake_image_api_connection: "error",
      },
    });
  }
});

// Error handling middleware
app.use((err, req, res, next) => {
  console.error(err.stack);
  res.status(500).json({ message: "Internal server error." });
});

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