import express from "express";
import multer from "multer";
import dotenv from "dotenv";
import cors from "cors";
import fetch from "node-fetch";

dotenv.config();

const app = express();
const port = process.env.PORT || 5000;
const upload = multer({ storage: multer.memoryStorage() });

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

app.get("/", (req, res) => {
  res.send("Hello World!");
});

app.post("/extract", upload.single("file"), async (req, res) => {
  if (!req.file) {
    return res.status(400).json({ error: "No file uploaded" });
  }

  try {
    const base64Image = req.file.buffer.toString("base64"); // Convert image to Base64

    const requestBody = {
      model: "pixtral-12b",
      messages: [
        {
          role: "user",
          content: [
            { type: "text", text: "Extract invoice details from this image. Now for extracting the details, I want JSON of this invoice. The main reason behind this is that invoices do not have a fixed format, but with JSON it will be in a fixed format. So please output as JSON only, nothing else, just JSON." },
            { type: "image_url", image_url: `data:image/jpeg;base64,${base64Image}` }
          ],
        },
      ],
    };

    const controller = new AbortController();
    const timeoutId = setTimeout(() => controller.abort(), 30000); // 30 seconds timeout

    const response = await fetch("https://api.mistral.ai/v1/chat/completions", {
      method: "POST",
      headers: {
        "Authorization": `Bearer ${process.env.MISTRAL_API_KEY}`,
        "Content-Type": "application/json",
      },
      body: JSON.stringify(requestBody),
      signal: controller.signal,
    });

    clearTimeout(timeoutId);

    console.log("Mistral API Response Status:", response.status);

    if (!response.ok) {
      const errorResponse = await response.text();
      console.error("Error Response:", errorResponse);
      return res.status(response.status).json({ error: errorResponse });
    }

    const data = await response.json();
    console.log("Mistral API Response:", JSON.stringify(data, null, 2));

    const jsonContent = data.choices[0].message.content;
    const cleanedJsonContent = jsonContent.replace(/```json\n|\n```/g, '');

    let invoiceData;
    try {
      invoiceData = JSON.parse(cleanedJsonContent);
    } catch (parseError) {
      console.error("Error parsing JSON:", parseError);
      return res.status(500).json({ error: "Error parsing JSON response" });
    }

    res.json(invoiceData);
  } catch (error) {
    if (error.name === 'AbortError') {
      console.error("Request timed out");
      return res.status(504).json({ error: "Request timed out" });
    }
    console.error("Error:", error.message);
    res.status(500).json({ error: error.message });
  }
});

app.listen(port, "0.0.0.0", () => {
  console.log(`Server running on port ${port}`);
});