// content.js - Amazon price extraction
function extractAmazonPrice() {
  const result = {
    currentPrice: null,
    originalPrice: null,
    discount: null,
    currency: 'USD',
    asin: null,
    productTitle: null,
    timestamp: new Date().toISOString()
  };

  // Extract ASIN from URL or page
  const urlMatch = window.location.pathname.match(/\/dp\/([A-Z0-9]{10})/);
  const asinMatch = document.querySelector('[data-asin]');
  result.asin = urlMatch ? urlMatch[1] : asinMatch?.getAttribute('data-asin');

  // Extract product title
  const titleElement = document.getElementById('productTitle');
  result.productTitle = titleElement ? titleElement.textContent.trim() : '';

  // Extract current price - multiple strategies
  const priceWhole = document.querySelector('.a-price-whole');
  const priceFraction = document.querySelector('.a-price-fraction');
  
  if (priceWhole) {
    const whole = priceWhole.textContent.replace(/[^0-9]/g, '');
    const fraction = priceFraction ? priceFraction.textContent : '00';
    result.currentPrice = parseFloat(`${whole}.${fraction}`);
  }

  // Extract original price (if discounted)
  const originalPriceElement = document.querySelector('.a-text-price .a-offscreen');
  if (originalPriceElement) {
    const originalText = originalPriceElement.textContent;
    const originalMatch = originalText.match(/[\d,]+\.?\d*/);
    if (originalMatch) {
      result.originalPrice = parseFloat(originalMatch[0].replace(/,/g, ''));
    }
  }

  // Calculate discount percentage
  if (result.currentPrice && result.originalPrice && result.originalPrice > 0) {
    result.discount = Math.round(((result.originalPrice - result.currentPrice) / result.originalPrice) * 100);
  }

  return result;
}

// Listen for messages from popup or background
chrome.runtime.onMessage.addListener((request, sender, sendResponse) => {
  if (request.action === 'getPriceData') {
    const priceData = extractAmazonPrice();
    sendResponse(priceData);
  }
  return true;
});

// background.js - Price storage and tracking
const PRICE_STORAGE_KEY = 'amazon_price_history';

async function savePriceData(asin, priceData) {
  const storage = await chrome.storage.local.get(PRICE_STORAGE_KEY);
  const history = storage[PRICE_STORAGE_KEY] || {};
  
  if (!history[asin]) {
    history[asin] = {
      productTitle: priceData.productTitle,
      prices: [],
      lowestPrice: priceData.currentPrice,
      highestPrice: priceData.currentPrice,
      lastChecked: priceData.timestamp
    };
  }
  
  const productHistory = history[asin];
  
  // Add new price entry
  productHistory.prices.push({
    price: priceData.currentPrice,
    timestamp: priceData.timestamp
  });
  
  // Update price bounds
  productHistory.lowestPrice = Math.min(productHistory.lowestPrice, priceData.currentPrice);
  productHistory.highestPrice = Math.max(productHistory.highestPrice, priceData.currentPrice);
  productHistory.lastChecked = priceData.timestamp;
  
  // Keep only last 90 days of data
  const cutoffDate = new Date();
  cutoffDate.setDate(cutoffDate.getDate() - 90);
  productHistory.prices = productHistory.prices.filter(
    entry => new Date(entry.timestamp) > cutoffDate
  );
  
  await chrome.storage.local.set({ [PRICE_STORAGE_KEY]: history });
  return productHistory;
}

async function getPriceHistory(asin) {
  const storage = await chrome.storage.local.get(PRICE_STORAGE_KEY);
  return storage[PRICE_STORAGE_KEY]?.[asin] || null;
}

// background.js - Price alert system
async function checkPriceAlerts(asin, currentPrice) {
  const storage = await chrome.storage.local.get('priceAlerts');
  const alerts = storage.priceAlerts || [];
  const matchingAlerts = alerts.filter(alert => 
    alert.asin === asin && 
    currentPrice <= alert.targetPrice
  );
  
  for (const alert of matchingAlerts) {
    await sendPriceNotification(alert, currentPrice);
    
    // Remove triggered one-time alerts
    if (!alert.recurring) {
      const updatedAlerts = alerts.filter(a => a.id !== alert.id);
      await chrome.storage.local.set({ priceAlerts: updatedAlerts });
    }
  }
}

async function sendPriceNotification(alert, currentPrice) {
  const notification = await chrome.notifications.create({
    type: 'basic',
    iconUrl: 'icon.png',
    title: 'Amazon Price Drop Alert!',
    message: `${alert.productName} is now $${currentPrice} (target: $${alert.targetPrice})`,
    priority: 2
  });
  
  // Optionally open the product page on click
  chrome.notifications.onClicked.addListener((notificationId) => {
    if (notificationId === notification) {
      chrome.tabs.create({ url: `https://www.amazon.com/dp/${alert.asin}` });
    }
  });
}

// popup.js
document.addEventListener('DOMContentLoaded', async () => {
  const [tab] = await chrome.tabs.query({ active: true, currentWindow: true });
  
  // Check if on Amazon product page
  if (tab.url?.includes('amazon.com/dp/')) {
    document.getElementById('trackCurrentBtn').style.display = 'block';
    document.getElementById('trackCurrentBtn').addEventListener('click', async () => {
      const response = await chrome.tabs.sendMessage(tab.id, { action: 'getPriceData' });
      if (response?.asin) {
        await savePriceData(response.asin, response);
        loadTrackedProducts();
      }
    });
  }
  
  loadTrackedProducts();
});

async function loadTrackedProducts() {
  const storage = await chrome.storage.local.get('amazon_price_history');
  const history = storage.amazon_price_history || {};
  const container = document.getElementById('trackedProducts');
  
  container.innerHTML = '';
  
  for (const [asin, data] of Object.entries(history)) {
    const latestPrice = data.prices[data.prices.length - 1]?.price;
    const card = document.createElement('div');
    card.className = 'product-card';
    card.innerHTML = `
      <div class="product-title">${data.productTitle?.substring(0, 50)}...</div>
      <div class="price-row">
        <span class="current-price">$${latestPrice}</span>
        <span class="price-range">Low: $${data.lowestPrice} | High: $${data.highestPrice}</span>
      </div>
      <button class="alert-btn" data-asin="${asin}" data-price="${latestPrice}">
        Set Alert
      </button>
    `;
    container.appendChild(card);
  }
}