/**
 * Popup UI Logic
 */

import './popup.css';
import { loadCredentials, saveCredentials, deleteCredentials, updateLastUse } from '../utils/storage';
import { uploadPDF, testConnection, BinectAPIError } from '../utils/binect-api';
import { fetchPDFBytes, DetectedPDF } from '../utils/pdf-detector';
import { addTrackingEntry } from '../tracking/tracker';

// DOM Elements
const authView = document.getElementById('authView')!;
const mainView = document.getElementById('mainView')!;
const noPdfView = document.getElementById('noPdfView')!;
const pdfView = document.getElementById('pdfView')!;

const loginForm = document.getElementById('loginForm') as HTMLFormElement;
const usernameInput = document.getElementById('username') as HTMLInputElement;
const passwordInput = document.getElementById('password') as HTMLInputElement;
const loginBtn = document.getElementById('loginBtn') as HTMLButtonElement;
const authError = document.getElementById('authError')!;

const pdfFilename = document.getElementById('pdfFilename')!;
const pdfSize = document.getElementById('pdfSize')!;
const pdfDomain = document.getElementById('pdfDomain')!;
const pdfTimestamp = document.getElementById('pdfTimestamp')!;

const sendBtn = document.getElementById('sendBtn') as HTMLButtonElement;
const statusMessage = document.getElementById('statusMessage')!;

const logoutBtn = document.getElementById('logoutBtn')!;
const helpBtn = document.getElementById('helpBtn')!;
const togglePasswordBtn = document.getElementById('togglePassword') as HTMLButtonElement;
const eyeIcon = document.getElementById('eyeIcon')!;
const eyeOffIcon = document.getElementById('eyeOffIcon')!;

// State
let currentPDF: DetectedPDF | null = null;
let currentCredentials: { username: string; password: string } | null = null;

/**
 * Initialize popup
 */
async function init() {
  // Check if user has credentials
  const credentials = await loadCredentials();

  if (credentials) {
    // Try to test connection
    try {
      const isConnected = await testConnection(credentials.username, credentials.password);

      if (isConnected) {
        currentCredentials = credentials;
        await updateLastUse();

        showMainView();
        await loadLastPDF();
      } else {
        // Authentication failed, credentials may be invalid
        showAuthView();
      }
    } catch (error) {
      // Connection test failed
      console.error('[Popup] Connection test failed:', error);
      showAuthView();
    }
  } else {
    showAuthView();
  }

  // Setup event listeners
  setupEventListeners();
}

/**
 * Setup event listeners
 */
function setupEventListeners() {
  loginForm.addEventListener('submit', handleLogin);
  sendBtn.addEventListener('click', handleSendPDF);
  logoutBtn.addEventListener('click', handleLogout);
  helpBtn.addEventListener('click', handleHelp);
  togglePasswordBtn.addEventListener('click', handleTogglePassword);
}

/**
 * Handle password visibility toggle
 */
function handleTogglePassword() {
  const isPassword = passwordInput.type === 'password';

  if (isPassword) {
    // Show password
    passwordInput.type = 'text';
    eyeIcon.style.display = 'none';
    eyeOffIcon.style.display = 'block';
    togglePasswordBtn.setAttribute('aria-label', 'Hide password');
    togglePasswordBtn.setAttribute('title', 'Hide password');
  } else {
    // Hide password
    passwordInput.type = 'password';
    eyeIcon.style.display = 'block';
    eyeOffIcon.style.display = 'none';
    togglePasswordBtn.setAttribute('aria-label', 'Show password');
    togglePasswordBtn.setAttribute('title', 'Show password');
  }
}

/**
 * Handle login
 */
async function handleLogin(e: Event) {
  e.preventDefault();

  const username = usernameInput.value.trim();
  const password = passwordInput.value;

  if (!username || !password) {
    showError('Please enter username and password');
    return;
  }

  loginBtn.disabled = true;
  loginBtn.textContent = 'Signing in...';
  hideError();

  try {
    const isConnected = await testConnection(username, password);

    if (!isConnected) {
      showError('Invalid credentials. Please check your username and password.');
      return;
    }

    // Save credentials
    currentCredentials = { username, password };
    await saveCredentials({ username, password });

    showMainView();
    await loadLastPDF();
  } catch (error) {
    if (error instanceof BinectAPIError) {
      showError(error.message);
    } else {
      showError('Authentication failed. Please try again.');
    }
  } finally {
    loginBtn.disabled = false;
    loginBtn.textContent = 'Sign In';
  }
}

/**
 * Handle send PDF
 */
async function handleSendPDF() {
  if (!currentPDF || !currentCredentials) {
    return;
  }

  sendBtn.disabled = true;
  showStatus('Uploading...', 'uploading');

  try {
    // Fetch PDF bytes
    const pdfBytes = await fetchPDFBytes(currentPDF.url);

    // Upload to Binect with credentials
    const document = await uploadPDF(
      pdfBytes,
      currentPDF.filename,
      currentCredentials.username,
      currentCredentials.password
    );

    // Track successful transfer
    await addTrackingEntry({
      timestamp: Date.now(),
      sourceDomain: currentPDF.sourceDomain,
      destinationUrl: 'https://api.binect.de/binectapi/v1/documents',
      pdfSize: pdfBytes.byteLength, // Use actual size from fetched data
      result: 'success'
    });

    // Update last use timestamp
    await updateLastUse();

    // Notify background script
    chrome.runtime.sendMessage({ action: 'pdfSent' });

    showStatus(`Success! Document ID: ${document.id} (Status: ${document.status.text})`, 'success');

    // Clear PDF after 3 seconds
    setTimeout(() => {
      currentPDF = null;
      showNoPDF();
      hideStatus();
    }, 3000);
  } catch (error) {
    let errorMessage = 'Upload failed';

    if (error instanceof BinectAPIError) {
      errorMessage = error.message;

      // If auth error, might need to re-login
      if (error.statusCode === 401 || error.statusCode === 403) {
        errorMessage = 'Invalid credentials. Please sign in again.';
        setTimeout(() => {
          handleLogout();
        }, 2000);
      }
    } else if (error instanceof Error) {
      errorMessage = error.message;
    }

    // Track failed transfer
    await addTrackingEntry({
      timestamp: Date.now(),
      sourceDomain: currentPDF.sourceDomain,
      destinationUrl: 'https://api.binect.de/binectapi/v1/documents',
      pdfSize: currentPDF.size || 0,
      result: 'failure',
      errorMessage
    });

    showStatus(errorMessage, 'error');
  } finally {
    sendBtn.disabled = false;
  }
}

/**
 * Handle logout
 */
async function handleLogout() {
  await deleteCredentials();
  currentCredentials = null;
  currentPDF = null;

  // Clear form
  loginForm.reset();

  showAuthView();
}

/**
 * Handle help button
 */
function handleHelp() {
  // Open tracking page
  chrome.tabs.create({ url: chrome.runtime.getURL('tracking.html') });
}

/**
 * Load last detected PDF
 */
async function loadLastPDF() {
  console.log('[Popup] Loading last PDF...');

  // First, check if current tab is viewing a PDF
  const currentTabPDF = await checkCurrentTabForPDF();

  if (currentTabPDF) {
    console.log('[Popup] Found PDF in current tab:', currentTabPDF.filename);
    currentPDF = currentTabPDF;
    showPDF(currentPDF);
    return;
  }

  console.log('[Popup] No PDF in current tab, checking background script...');

  // If no PDF in current tab, ask background script for last detected download
  chrome.runtime.sendMessage({ action: 'getLastPDF' }, async (response) => {
    if (response && response.pdf && response.pdf !== null) {
      console.log('[Popup] Background returned PDF:', response.pdf.filename);
      currentPDF = response.pdf;
      showPDF(response.pdf);
    } else {
      console.log('[Popup] Background has no PDF, checking recent downloads as fallback...');

      // Fallback: Check recent downloads directly
      const recentPDF = await checkRecentDownloads();
      if (recentPDF !== null) {
        console.log('[Popup] Found recent PDF download:', recentPDF.filename);
        currentPDF = recentPDF;
        showPDF(recentPDF);
      } else {
        console.log('[Popup] No PDF found anywhere');
        showNoPDF();
      }
    }
  });
}

/**
 * Check recent downloads for PDFs (fallback mechanism)
 */
async function checkRecentDownloads(): Promise<DetectedPDF | null> {
  return new Promise((resolve) => {
    chrome.downloads.search(
      {
        limit: 20, // Check last 20 downloads
        orderBy: ['-startTime']
      },
      (items) => {
        console.log('[Popup] Checked recent downloads:', items.length, 'items');

        // Find most recent completed PDF
        const pdfItem = items.find(
          (item) =>
            item.state === 'complete' &&
            (item.filename.toLowerCase().endsWith('.pdf') || item.mime === 'application/pdf')
        );

        if (pdfItem) {
          console.log('[Popup] Found recent PDF:', pdfItem.filename);

          // Extract domain
          let domain = 'unknown';
          try {
            const urlObj = new URL(pdfItem.url);
            domain = urlObj.hostname;
          } catch (e) {
            // Keep default
          }

          resolve({
            id: `download-${pdfItem.id}`,
            filename: pdfItem.filename.split('/').pop() || pdfItem.filename,
            url: pdfItem.url,
            size: pdfItem.fileSize,
            timestamp: Date.now(), // Use current time as approximation
            sourceDomain: domain
          });
        } else {
          console.log('[Popup] No recent PDF downloads found');
          resolve(null);
        }
      }
    );
  });
}

/**
 * Check if the current active tab is viewing a PDF
 */
async function checkCurrentTabForPDF(): Promise<DetectedPDF | null> {
  try {
    const [tab] = await chrome.tabs.query({ active: true, currentWindow: true });

    if (!tab || !tab.url) {
      return null;
    }

    // Check if the URL is a PDF
    const url = tab.url;
    const isPDF = url.toLowerCase().endsWith('.pdf') ||
                  url.includes('type=application/pdf') ||
                  url.includes('mime=application/pdf');

    if (isPDF) {
      // Extract filename from URL
      let filename = 'document.pdf';
      try {
        const urlObj = new URL(url);
        const pathname = urlObj.pathname;
        const pathParts = pathname.split('/');
        const lastPart = pathParts[pathParts.length - 1];
        if (lastPart && lastPart.toLowerCase().endsWith('.pdf')) {
          filename = decodeURIComponent(lastPart);
        } else if (tab.title && tab.title !== 'about:blank' && !tab.title.startsWith('chrome://')) {
          // Use tab title if available
          filename = tab.title.endsWith('.pdf') ? tab.title : `${tab.title}.pdf`;
        }
      } catch (e) {
        // Use tab title as fallback
        if (tab.title && tab.title !== 'about:blank') {
          filename = tab.title.endsWith('.pdf') ? tab.title : `${tab.title}.pdf`;
        }
      }

      // Extract domain
      let domain = 'unknown';
      try {
        const urlObj = new URL(url);
        domain = urlObj.hostname;
      } catch (e) {
        // Keep default
      }

      return {
        id: `tab-${tab.id}`,
        filename,
        url,
        size: 0, // Unknown size for viewed PDFs
        timestamp: Date.now(),
        sourceDomain: domain
      };
    }

    return null;
  } catch (error) {
    console.error('Error checking current tab for PDF:', error);
    return null;
  }
}

/**
 * Show auth view
 */
function showAuthView() {
  authView.style.display = 'block';
  mainView.style.display = 'none';
}

/**
 * Show main view
 */
function showMainView() {
  authView.style.display = 'none';
  mainView.style.display = 'block';
}

/**
 * Show no PDF view
 */
function showNoPDF() {
  noPdfView.style.display = 'block';
  pdfView.style.display = 'none';
}

/**
 * Show PDF view
 */
function showPDF(pdf: DetectedPDF) {
  noPdfView.style.display = 'none';
  pdfView.style.display = 'block';

  pdfFilename.textContent = pdf.filename;
  pdfSize.textContent = formatFileSize(pdf.size);
  pdfDomain.textContent = pdf.sourceDomain;
  pdfTimestamp.textContent = formatTimestamp(pdf.timestamp);

  sendBtn.disabled = false;
  hideStatus();
}

/**
 * Show error message
 */
function showError(message: string) {
  authError.textContent = message;
  authError.style.display = 'block';
}

/**
 * Hide error message
 */
function hideError() {
  authError.style.display = 'none';
}

/**
 * Show status message
 */
function showStatus(message: string, type: 'uploading' | 'success' | 'error') {
  statusMessage.textContent = message;
  statusMessage.className = `status-message ${type}`;
  statusMessage.style.display = 'block';
}

/**
 * Hide status message
 */
function hideStatus() {
  statusMessage.style.display = 'none';
}

/**
 * Format file size
 */
function formatFileSize(bytes: number): string {
  if (bytes === 0) {
    return 'Size unknown';
  } else if (bytes < 1024) {
    return `${bytes} B`;
  } else if (bytes < 1024 * 1024) {
    return `${(bytes / 1024).toFixed(1)} KB`;
  } else {
    return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
  }
}

/**
 * Format timestamp
 */
function formatTimestamp(timestamp: number): string {
  const now = Date.now();
  const diff = now - timestamp;

  if (diff < 60 * 1000) {
    return 'Just now';
  } else if (diff < 60 * 60 * 1000) {
    const minutes = Math.floor(diff / (60 * 1000));
    return `${minutes} minute${minutes > 1 ? 's' : ''} ago`;
  } else if (diff < 24 * 60 * 60 * 1000) {
    const hours = Math.floor(diff / (60 * 60 * 1000));
    return `${hours} hour${hours > 1 ? 's' : ''} ago`;
  } else {
    return new Date(timestamp).toLocaleDateString();
  }
}

// Initialize on load
init();