import puppeteer from "puppeteer";
import express from "express";
import "dotenv/config";

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

// Symbol configuration
const symbols = {
  BPIDEST2040: {
    url: "https://www.bancobpi.pt/particulares/poupar-investir/ppr/bpi-destino-ppr-2040",
    name: "BPI Destino PPR 2040",
  },
  BPIDEST2050: {
    url: "https://www.bancobpi.pt/particulares/poupar-investir/ppr/bpi-destino-ppr-2050",
    name: "BPI Destino PPR 2050",
  },
};

// Function to scrape price for a given symbol
async function getLatestPrice(symbol) {
  const config = symbols[symbol];

  if (!config) {
    throw new Error(`Invalid symbol: ${symbol}`);
  }

  // Launch the browser
  const browser = await puppeteer.launch({
    args: ["--no-sandbox"],
    timeout: 10000,
  });

  try {
    // Open a new tab
    const page = await browser.newPage();

    // Visit the page and wait until network connections are completed
    await page.goto(config.url, { waitUntil: "networkidle2" });

    // Interact with the DOM to retrieve the price and date
    const [price, date] = await page.evaluate(() => {
      const spanTags = document.getElementsByTagName("span");
      const priceSearchText = "ÚLTIMA COTAÇÃO:";
      const dateSearchText = "DATA COTAÇÃO:";
      let priceElementFound;
      let dateElementFound;

      for (let i = 0; i < spanTags.length; i++) {
        if (spanTags[i].textContent.trim() == priceSearchText) {
          priceElementFound = spanTags[i];
          if (priceElementFound && dateElementFound) break;
        }
        if (spanTags[i].textContent.trim() == dateSearchText) {
          dateElementFound = spanTags[i];
          if (priceElementFound && dateElementFound) break;
        }
      }

      if (!priceElementFound || !dateElementFound) {
        throw new Error("Could not find price or date elements");
      }

      return [
        priceElementFound.nextSibling.innerHTML,
        dateElementFound.nextSibling.innerHTML,
      ];
    });

    const marketPrice = parseFloat(
      price.replace("€", "").trim().replace(",", "."),
    );

    return {
      symbol,
      name: config.name,
      price: marketPrice,
      date: date.trim(),
      timestamp: new Date().toISOString(),
    };
  } finally {
    // Always close the browser
    await browser.close();
  }
}

// API endpoint to get latest price for a symbol
app.get("/price/:symbol", async (req, res) => {
  const { symbol } = req.params;

  try {
    console.log(`Fetching price for symbol: ${symbol}`);
    const priceData = await getLatestPrice(symbol);
    console.log(`Success: ${symbol} - €${priceData.price}`);
    res.json(priceData);
  } catch (error) {
    console.error(`Error fetching price for ${symbol}:`, error.message);
    res.status(400).json({
      error: error.message,
      symbol,
    });
  }
});

// Health check endpoint
app.get("/health", (req, res) => {
  res.json({ status: "ok", availableSymbols: Object.keys(symbols) });
});

// Root endpoint with usage instructions
app.get("/", (req, res) => {
  res.json({
    message: "BPI Stock Price Scraper API",
    endpoints: {
      health: "/health",
      price: "/price/:symbol",
    },
    availableSymbols: Object.keys(symbols),
    example: `/price/BPIDEST2040`,
  });
});

// Start the server
app.listen(PORT, () => {
  console.log(`Server running on http://localhost:${PORT}`);
  console.log(`Available symbols: ${Object.keys(symbols).join(", ")}`);
  console.log(`Example: http://localhost:${PORT}/price/BPIDEST2040`);
});