/**
 * Popup UI Logic
 */

import { loadCredentials, saveCredentials, deleteCredentials, updateLastUse } from '../utils/storage';
import { authenticate, uploadPDF, 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')!;

// State
let currentPDF: DetectedPDF | null = null;
let authToken: string | null = null;

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

  if (credentials) {
    // Try to authenticate
    try {
      const token = await authenticate(credentials.username, credentials.password);
      authToken = token.token;
      await updateLastUse();

      showMainView();
      await loadLastPDF();
    } catch (error) {
      // Authentication failed, credentials may be invalid
      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);
}

/**
 * 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 token = await authenticate(username, password);
    authToken = token.token;

    // Save credentials
    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 || !authToken) {
    return;
  }

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

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

    // Upload to Binect
    const result = await uploadPDF(pdfBytes, currentPDF.filename, authToken);

    // Track successful transfer
    await addTrackingEntry({
      timestamp: Date.now(),
      sourceDomain: currentPDF.sourceDomain,
      destinationUrl: 'https://api.binect.de/documents/upload',
      pdfSize: currentPDF.size,
      result: 'success'
    });

    // Update last use timestamp
    await updateLastUse();

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

    showStatus(`Success! Document ID: ${result.documentId}`, '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) {
        errorMessage = 'Session expired. 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/documents/upload',
      pdfSize: currentPDF.size,
      result: 'failure',
      errorMessage
    });

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

/**
 * Handle logout
 */
async function handleLogout() {
  await deleteCredentials();
  authToken = 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() {
  // Ask background script for last PDF
  chrome.runtime.sendMessage({ action: 'getLastPDF' }, (response) => {
    if (response && response.pdf) {
      currentPDF = response.pdf;
      if (currentPDF) {
        showPDF(currentPDF);
      } else {
        showNoPDF();
      }
    } else {
      showNoPDF();
    }
  });
}

/**
 * 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 < 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();