// Import our WebAssembly module
import init, {
  create_key_space,
  encrypt_key_space,
  decrypt_key_space,
  logout,
  create_keypair,
  select_keypair,
  list_keypairs,
  keypair_pub_key,
  keypair_sign,
  keypair_verify,
  derive_public_key,
  verify_with_public_key,
  encrypt_asymmetric,
  decrypt_asymmetric,
  generate_symmetric_key,
  derive_key_from_password,
  encrypt_symmetric,
  decrypt_symmetric,
  encrypt_with_password,
  decrypt_with_password
} from '../../pkg/webassembly.js';

// Helper function to convert ArrayBuffer to hex string
function bufferToHex(buffer) {
  return Array.from(new Uint8Array(buffer))
    .map(b => b.toString(16).padStart(2, '0'))
    .join('');
}

// Helper function to convert hex string to Uint8Array
function hexToBuffer(hex) {
  const bytes = new Uint8Array(hex.length / 2);
  for (let i = 0; i < hex.length; i += 2) {
    bytes[i / 2] = parseInt(hex.substr(i, 2), 16);
  }
  return bytes;
}

// Session management
let lastActivity = Date.now();
let logoutTimer = null;
const AUTO_LOGOUT_TIME = 15 * 60 * 1000; // 15 minutes

// Update last activity timestamp
function updateActivity() {
  lastActivity = Date.now();
}

// Check for inactivity and logout if needed
function checkInactivity() {
  const inactiveTime = Date.now() - lastActivity;
  if (inactiveTime > AUTO_LOGOUT_TIME) {
    performLogout();
    alert('You have been logged out due to inactivity.');
  }
}

// Setup auto-logout timer
function setupAutoLogout() {
  logoutTimer = setInterval(checkInactivity, 60000); // Check every minute
}

// Clear auto-logout timer
function clearAutoLogout() {
  if (logoutTimer) {
    clearInterval(logoutTimer);
    logoutTimer = null;
  }
}

// LocalStorage functions for key spaces
const STORAGE_PREFIX = 'crypto_space_';

// Save encrypted space to localStorage
function saveSpaceToStorage(spaceName, encryptedData) {
  localStorage.setItem(`${STORAGE_PREFIX}${spaceName}`, encryptedData);
}

// Get encrypted space from localStorage
function getSpaceFromStorage(spaceName) {
  return localStorage.getItem(`${STORAGE_PREFIX}${spaceName}`);
}

// List all spaces in localStorage
function listSpacesFromStorage() {
  const spaces = [];
  for (let i = 0; i < localStorage.length; i++) {
    const key = localStorage.key(i);
    if (key.startsWith(STORAGE_PREFIX)) {
      spaces.push(key.substring(STORAGE_PREFIX.length));
    }
  }
  return spaces;
}

// Remove space from localStorage
function removeSpaceFromStorage(spaceName) {
  localStorage.removeItem(`${STORAGE_PREFIX}${spaceName}`);
}

// Session state
let isLoggedIn = false;
let currentSpace = null;
let selectedKeypair = null;

// Update UI based on login state
function updateLoginUI() {
  const loginForm = document.getElementById('login-form');
  const logoutForm = document.getElementById('logout-form');
  const loginStatus = document.getElementById('login-status');
  const currentSpaceName = document.getElementById('current-space-name');
  
  if (isLoggedIn) {
    loginForm.classList.add('hidden');
    logoutForm.classList.remove('hidden');
    loginStatus.textContent = 'Status: Logged in';
    loginStatus.className = 'status logged-in';
    currentSpaceName.textContent = currentSpace;
  } else {
    loginForm.classList.remove('hidden');
    logoutForm.classList.add('hidden');
    loginStatus.textContent = 'Status: Not logged in';
    loginStatus.className = 'status logged-out';
    currentSpaceName.textContent = '';
  }
  
  // Update the spaces list
  updateSpacesList();
}

// Update the spaces dropdown list
function updateSpacesList() {
  const spacesList = document.getElementById('space-list');
  
  // Clear existing options
  while (spacesList.options.length > 1) {
    spacesList.remove(1);
  }
  
  // Get spaces list
  const spaces = listSpacesFromStorage();
  
  // Add options for each space
  spaces.forEach(spaceName => {
    const option = document.createElement('option');
    option.value = spaceName;
    option.textContent = spaceName;
    spacesList.appendChild(option);
  });
}

// Login to a space
async function performLogin() {
  const spaceName = document.getElementById('space-name').value.trim();
  const password = document.getElementById('space-password').value;
  
  if (!spaceName || !password) {
    document.getElementById('space-result').textContent = 'Please enter both space name and password';
    return;
  }
  
  try {
    // Get encrypted space from localStorage
    const encryptedSpace = getSpaceFromStorage(spaceName);
    if (!encryptedSpace) {
      document.getElementById('space-result').textContent = `Space "${spaceName}" not found`;
      return;
    }
    
    // Decrypt the space
    const result = decrypt_key_space(encryptedSpace, password);
    if (result === 0) {
      isLoggedIn = true;
      currentSpace = spaceName;
      updateLoginUI();
      updateKeypairsList();
      document.getElementById('space-result').textContent = `Successfully logged in to space "${spaceName}"`;
      
      // Setup auto-logout
      updateActivity();
      setupAutoLogout();
      
      // Add activity listeners
      document.addEventListener('click', updateActivity);
      document.addEventListener('keypress', updateActivity);
    } else {
      document.getElementById('space-result').textContent = `Error logging in: ${result}`;
    }
  } catch (e) {
    document.getElementById('space-result').textContent = `Error: ${e}`;
  }
}

// Create a new space
async function performCreateSpace() {
  const spaceName = document.getElementById('space-name').value.trim();
  const password = document.getElementById('space-password').value;
  
  if (!spaceName || !password) {
    document.getElementById('space-result').textContent = 'Please enter both space name and password';
    return;
  }
  
  // Check if space already exists
  if (getSpaceFromStorage(spaceName)) {
    document.getElementById('space-result').textContent = `Space "${spaceName}" already exists`;
    return;
  }
  
  try {
    // Create new space
    const result = create_key_space(spaceName);
    if (result === 0) {
      // Encrypt and save the space
      const encryptedSpace = encrypt_key_space(password);
      saveSpaceToStorage(spaceName, encryptedSpace);
      
      isLoggedIn = true;
      currentSpace = spaceName;
      updateLoginUI();
      updateKeypairsList();
      document.getElementById('space-result').textContent = `Successfully created space "${spaceName}"`;
      
      // Setup auto-logout
      updateActivity();
      setupAutoLogout();
      
      // Add activity listeners
      document.addEventListener('click', updateActivity);
      document.addEventListener('keypress', updateActivity);
    } else {
      document.getElementById('space-result').textContent = `Error creating space: ${result}`;
    }
  } catch (e) {
    document.getElementById('space-result').textContent = `Error: ${e}`;
  }
}

// Logout from current space
function performLogout() {
  logout();
  isLoggedIn = false;
  currentSpace = null;
  selectedKeypair = null;
  updateLoginUI();
  clearKeypairsList();
  document.getElementById('space-result').textContent = 'Logged out successfully';
  
  // Clear auto-logout
  clearAutoLogout();
  
  // Remove activity listeners
  document.removeEventListener('click', updateActivity);
  document.removeEventListener('keypress', updateActivity);
}

// Update the keypairs dropdown list
function updateKeypairsList() {
  const selectKeypair = document.getElementById('select-keypair');
  
  // Clear existing options
  while (selectKeypair.options.length > 1) {
    selectKeypair.remove(1);
  }
  
  try {
    // Get keypairs list
    const keypairs = list_keypairs();
    
    // Add options for each keypair
    keypairs.forEach(keypairName => {
      const option = document.createElement('option');
      option.value = keypairName;
      option.textContent = keypairName;
      selectKeypair.appendChild(option);
    });
    
    // If there's a selected keypair, select it in the dropdown
    if (selectedKeypair) {
      selectKeypair.value = selectedKeypair;
    }
  } catch (e) {
    console.error('Error updating keypairs list:', e);
  }
}

// Clear the keypairs dropdown list
function clearKeypairsList() {
  const selectKeypair = document.getElementById('select-keypair');
  
  // Clear existing options
  while (selectKeypair.options.length > 1) {
    selectKeypair.remove(1);
  }
  
  // Clear selected keypair display
  document.getElementById('selected-pubkey-display').textContent = '';
}

// Create a new keypair
async function performCreateKeypair() {
  if (!isLoggedIn) {
    document.getElementById('keypair-management-result').textContent = 'Please login first';
    return;
  }
  
  const keypairName = document.getElementById('keypair-name').value.trim();
  
  if (!keypairName) {
    document.getElementById('keypair-management-result').textContent = 'Please enter a keypair name';
    return;
  }
  
  try {
    // Create new keypair
    const result = create_keypair(keypairName);
    if (result === 0) {
      document.getElementById('keypair-management-result').textContent = `Successfully created keypair "${keypairName}"`;
      
      // Update keypairs list
      updateKeypairsList();
      
      // Select the new keypair
      selectedKeypair = keypairName;
      document.getElementById('select-keypair').value = keypairName;
      
      // Display public key
      displaySelectedKeypairPublicKey();
      
      // Save the updated space to localStorage
      saveCurrentSpace();
    } else {
      document.getElementById('keypair-management-result').textContent = `Error creating keypair: ${result}`;
    }
  } catch (e) {
    document.getElementById('keypair-management-result').textContent = `Error: ${e}`;
  }
}

// Select a keypair
async function performSelectKeypair() {
  if (!isLoggedIn) {
    document.getElementById('keypair-management-result').textContent = 'Please login first';
    return;
  }
  
  const keypairName = document.getElementById('select-keypair').value;
  
  if (!keypairName) {
    document.getElementById('keypair-management-result').textContent = 'Please select a keypair';
    return;
  }
  
  try {
    // Select keypair
    const result = select_keypair(keypairName);
    if (result === 0) {
      selectedKeypair = keypairName;
      document.getElementById('keypair-management-result').textContent = `Selected keypair "${keypairName}"`;
      
      // Display public key
      displaySelectedKeypairPublicKey();
    } else {
      document.getElementById('keypair-management-result').textContent = `Error selecting keypair: ${result}`;
    }
  } catch (e) {
    document.getElementById('keypair-management-result').textContent = `Error: ${e}`;
  }
}

// Display the public key of the selected keypair
function displaySelectedKeypairPublicKey() {
  try {
    const pubKey = keypair_pub_key();
    const pubKeyHex = bufferToHex(pubKey);
    
    // Create a more user-friendly display with copy button
    const pubKeyDisplay = document.getElementById('selected-pubkey-display');
    pubKeyDisplay.innerHTML = `
      <div class="pubkey-container">
        <div class="pubkey-label">Public Key (hex):</div>
        <div class="pubkey-value" id="pubkey-hex-value">${pubKeyHex}</div>
        <button id="copy-pubkey-button" class="secondary">Copy Public Key</button>
      </div>
    `;
    
    // Add event listener for the copy button
    document.getElementById('copy-pubkey-button').addEventListener('click', () => {
      const pubKeyText = document.getElementById('pubkey-hex-value').textContent;
      navigator.clipboard.writeText(pubKeyText)
        .then(() => {
          alert('Public key copied to clipboard!');
        })
        .catch(err => {
          console.error('Could not copy text: ', err);
        });
    });
    
    // Also populate the public key field in the verify with public key section
    document.getElementById('pubkey-verify-pubkey').value = pubKeyHex;
    
    // And in the asymmetric encryption section
    document.getElementById('asymmetric-encrypt-pubkey').value = pubKeyHex;
    
  } catch (e) {
    document.getElementById('selected-pubkey-display').textContent = `Error getting public key: ${e}`;
  }
}

// Save the current space to localStorage
function saveCurrentSpace() {
  if (!isLoggedIn || !currentSpace) return;
  
  try {
    // Store the password in a session variable when logging in
    // and use it here to avoid issues when the password field is cleared
    const password = document.getElementById('space-password').value;
    if (!password) {
      console.error('Password not available for saving space');
      alert('Please re-enter your password to save changes');
      return;
    }
    
    const encryptedSpace = encrypt_key_space(password);
    saveSpaceToStorage(currentSpace, encryptedSpace);
  } catch (e) {
    console.error('Error saving space:', e);
  }
}

// Delete a space from localStorage
function deleteSpace(spaceName) {
  if (!spaceName) return false;
  
  // Check if space exists
  if (!getSpaceFromStorage(spaceName)) {
    return false;
  }
  
  // Remove from localStorage
  removeSpaceFromStorage(spaceName);
  
  // If this was the current space, logout
  if (isLoggedIn && currentSpace === spaceName) {
    performLogout();
  }
  
  return true;
}

async function run() {
  // Initialize the WebAssembly module
  await init();
  
  console.log('WebAssembly crypto module initialized!');
  
  // Set up the login/space management
  document.getElementById('login-button').addEventListener('click', performLogin);
  document.getElementById('create-space-button').addEventListener('click', performCreateSpace);
  document.getElementById('logout-button').addEventListener('click', performLogout);
  document.getElementById('delete-space-button').addEventListener('click', () => {
    if (confirm(`Are you sure you want to delete the space "${currentSpace}"? This action cannot be undone.`)) {
      if (deleteSpace(currentSpace)) {
        document.getElementById('space-result').textContent = `Space "${currentSpace}" deleted successfully`;
      } else {
        document.getElementById('space-result').textContent = `Error deleting space "${currentSpace}"`;
      }
    }
  });
  
  document.getElementById('delete-selected-space-button').addEventListener('click', () => {
    const selectedSpace = document.getElementById('space-list').value;
    if (!selectedSpace) {
      document.getElementById('space-result').textContent = 'Please select a space to delete';
      return;
    }
    
    if (confirm(`Are you sure you want to delete the space "${selectedSpace}"? This action cannot be undone.`)) {
      if (deleteSpace(selectedSpace)) {
        document.getElementById('space-result').textContent = `Space "${selectedSpace}" deleted successfully`;
        updateSpacesList();
      } else {
        document.getElementById('space-result').textContent = `Error deleting space "${selectedSpace}"`;
      }
    }
  });
  
  // Set up the keypair management
  document.getElementById('create-keypair-button').addEventListener('click', performCreateKeypair);
  document.getElementById('select-keypair').addEventListener('change', performSelectKeypair);
  
  // Set up the signing example
  document.getElementById('sign-button').addEventListener('click', () => {
    if (!isLoggedIn) {
      document.getElementById('signature-result').textContent = 'Please login first';
      return;
    }
    
    if (!selectedKeypair) {
      document.getElementById('signature-result').textContent = 'Please select a keypair first';
      return;
    }
    
    const message = document.getElementById('sign-message').value;
    const messageBytes = new TextEncoder().encode(message);
    
    try {
      const signature = keypair_sign(messageBytes);
      const signatureHex = bufferToHex(signature);
      document.getElementById('signature-result').textContent = `Signature: ${signatureHex}`;
      
      // Store the signature for verification
      document.getElementById('verify-signature').value = signatureHex;
      document.getElementById('verify-message').value = message;
    } catch (e) {
      document.getElementById('signature-result').textContent = `Error signing: ${e}`;
    }
  });
  
  // Set up the verification example
  document.getElementById('verify-button').addEventListener('click', () => {
    if (!isLoggedIn) {
      document.getElementById('verify-result').textContent = 'Please login first';
      return;
    }
    
    if (!selectedKeypair) {
      document.getElementById('verify-result').textContent = 'Please select a keypair first';
      return;
    }
    
    const message = document.getElementById('verify-message').value;
    const messageBytes = new TextEncoder().encode(message);
    const signatureHex = document.getElementById('verify-signature').value;
    const signatureBytes = hexToBuffer(signatureHex);
    
    try {
      const isValid = keypair_verify(messageBytes, signatureBytes);
      document.getElementById('verify-result').textContent = 
        isValid ? 'Signature is valid!' : 'Signature is NOT valid!';
    } catch (e) {
      document.getElementById('verify-result').textContent = `Error verifying: ${e}`;
    }
  });
  
  // Set up the symmetric encryption example
  document.getElementById('encrypt-button').addEventListener('click', () => {
    try {
      // Generate key
      const key = generate_symmetric_key();
      
      // Display key
      const keyHex = bufferToHex(key);
      document.getElementById('sym-key-display').textContent = `Key: ${keyHex}`;
      
      // Store for decryption
      document.getElementById('decrypt-key').value = keyHex;
      
      // Encrypt the message
      const message = document.getElementById('encrypt-message').value;
      const messageBytes = new TextEncoder().encode(message);
      
      try {
        const ciphertext = encrypt_symmetric(key, messageBytes);
        const ciphertextHex = bufferToHex(ciphertext);
        document.getElementById('encrypt-result').textContent = `Ciphertext: ${ciphertextHex}`;
        
        // Store for decryption
        document.getElementById('decrypt-ciphertext').value = ciphertextHex;
      } catch (e) {
        document.getElementById('encrypt-result').textContent = `Error encrypting: ${e}`;
      }
    } catch (e) {
      document.getElementById('encrypt-result').textContent = `Error: ${e}`;
    }
  });
  
  // Set up the symmetric decryption example
  document.getElementById('decrypt-button').addEventListener('click', () => {
    try {
      const keyHex = document.getElementById('decrypt-key').value;
      const ciphertextHex = document.getElementById('decrypt-ciphertext').value;
      
      const key = hexToBuffer(keyHex);
      const ciphertext = hexToBuffer(ciphertextHex);
      
      try {
        const plaintext = decrypt_symmetric(key, ciphertext);
        const decodedText = new TextDecoder().decode(plaintext);
        document.getElementById('decrypt-result').textContent = `Decrypted: ${decodedText}`;
      } catch (e) {
        document.getElementById('decrypt-result').textContent = `Error decrypting: ${e}`;
      }
    } catch (e) {
      document.getElementById('decrypt-result').textContent = `Error: ${e}`;
    }
  });
  
  // Set up the password-based encryption example
  document.getElementById('password-encrypt-button').addEventListener('click', () => {
    try {
      const password = document.getElementById('password-encrypt-password').value;
      if (!password) {
        document.getElementById('password-encrypt-result').textContent = 'Please enter a password';
        return;
      }
      
      const message = document.getElementById('password-encrypt-message').value;
      const messageBytes = new TextEncoder().encode(message);
      
      const ciphertext = encrypt_with_password(password, messageBytes);
      const ciphertextHex = bufferToHex(ciphertext);
      document.getElementById('password-encrypt-result').textContent = `Ciphertext: ${ciphertextHex}`;
      
      // Store for decryption
      document.getElementById('password-decrypt-ciphertext').value = ciphertextHex;
      document.getElementById('password-decrypt-password').value = password;
    } catch (e) {
      document.getElementById('password-encrypt-result').textContent = `Error: ${e}`;
    }
  });
  
  // Set up the password-based decryption example
  document.getElementById('password-decrypt-button').addEventListener('click', () => {
    try {
      const password = document.getElementById('password-decrypt-password').value;
      if (!password) {
        document.getElementById('password-decrypt-result').textContent = 'Please enter a password';
        return;
      }
      
      const ciphertextHex = document.getElementById('password-decrypt-ciphertext').value;
      const ciphertext = hexToBuffer(ciphertextHex);
      
      const plaintext = decrypt_with_password(password, ciphertext);
      const decodedText = new TextDecoder().decode(plaintext);
      document.getElementById('password-decrypt-result').textContent = `Decrypted: ${decodedText}`;
    } catch (e) {
      document.getElementById('password-decrypt-result').textContent = `Error: ${e}`;
    }
  });

  // Set up the public key verification example
  document.getElementById('pubkey-verify-button').addEventListener('click', () => {
    try {
      const publicKeyHex = document.getElementById('pubkey-verify-pubkey').value.trim();
      if (!publicKeyHex) {
        document.getElementById('pubkey-verify-result').textContent = 'Please enter a public key';
        return;
      }

      const message = document.getElementById('pubkey-verify-message').value;
      const messageBytes = new TextEncoder().encode(message);
      const signatureHex = document.getElementById('pubkey-verify-signature').value;
      const signatureBytes = hexToBuffer(signatureHex);
      const publicKeyBytes = hexToBuffer(publicKeyHex);
      
      try {
        const isValid = verify_with_public_key(publicKeyBytes, messageBytes, signatureBytes);
        document.getElementById('pubkey-verify-result').textContent =
          isValid ? 'Signature is valid!' : 'Signature is NOT valid!';
      } catch (e) {
        document.getElementById('pubkey-verify-result').textContent = `Error verifying: ${e}`;
      }
    } catch (e) {
      document.getElementById('pubkey-verify-result').textContent = `Error: ${e}`;
    }
  });

  // Set up the derive public key example
  document.getElementById('derive-pubkey-button').addEventListener('click', () => {
    try {
      const privateKeyHex = document.getElementById('derive-pubkey-privkey').value.trim();
      if (!privateKeyHex) {
        document.getElementById('derive-pubkey-result').textContent = 'Please enter a private key';
        return;
      }

      const privateKeyBytes = hexToBuffer(privateKeyHex);
      
      try {
        const publicKey = derive_public_key(privateKeyBytes);
        const publicKeyHex = bufferToHex(publicKey);
        
        // Create a more user-friendly display with copy button
        const pubKeyDisplay = document.getElementById('derive-pubkey-result');
        pubKeyDisplay.innerHTML = `
          <div class="pubkey-container">
            <div class="pubkey-label">Derived Public Key (hex):</div>
            <div class="pubkey-value" id="derived-pubkey-hex-value">${publicKeyHex}</div>
            <button id="copy-derived-pubkey-button" class="secondary">Copy Public Key</button>
          </div>
        `;
        
        // Add event listener for the copy button
        document.getElementById('copy-derived-pubkey-button').addEventListener('click', () => {
          const pubKeyText = document.getElementById('derived-pubkey-hex-value').textContent;
          navigator.clipboard.writeText(pubKeyText)
            .then(() => {
              alert('Public key copied to clipboard!');
            })
            .catch(err => {
              console.error('Could not copy text: ', err);
            });
        });
        
        // Also populate the public key field in the verify with public key section
        document.getElementById('pubkey-verify-pubkey').value = publicKeyHex;
        
        // And in the asymmetric encryption section
        document.getElementById('asymmetric-encrypt-pubkey').value = publicKeyHex;
        
      } catch (e) {
        document.getElementById('derive-pubkey-result').textContent = `Error deriving public key: ${e}`;
      }
    } catch (e) {
      document.getElementById('derive-pubkey-result').textContent = `Error: ${e}`;
    }
  });

  // Set up the asymmetric encryption example
  document.getElementById('asymmetric-encrypt-button').addEventListener('click', () => {
    try {
      const publicKeyHex = document.getElementById('asymmetric-encrypt-pubkey').value.trim();
      if (!publicKeyHex) {
        document.getElementById('asymmetric-encrypt-result').textContent = 'Please enter a recipient public key';
        return;
      }

      const message = document.getElementById('asymmetric-encrypt-message').value;
      const messageBytes = new TextEncoder().encode(message);
      const publicKeyBytes = hexToBuffer(publicKeyHex);
      
      try {
        const ciphertext = encrypt_asymmetric(publicKeyBytes, messageBytes);
        const ciphertextHex = bufferToHex(ciphertext);
        document.getElementById('asymmetric-encrypt-result').textContent = `Ciphertext: ${ciphertextHex}`;
        
        // Store for decryption
        document.getElementById('asymmetric-decrypt-ciphertext').value = ciphertextHex;
      } catch (e) {
        document.getElementById('asymmetric-encrypt-result').textContent = `Error encrypting: ${e}`;
      }
    } catch (e) {
      document.getElementById('asymmetric-encrypt-result').textContent = `Error: ${e}`;
    }
  });

  // Set up the asymmetric decryption example
  document.getElementById('asymmetric-decrypt-button').addEventListener('click', () => {
    if (!isLoggedIn) {
      document.getElementById('asymmetric-decrypt-result').textContent = 'Please login first';
      return;
    }
    
    if (!selectedKeypair) {
      document.getElementById('asymmetric-decrypt-result').textContent = 'Please select a keypair first';
      return;
    }
    
    try {
      const ciphertextHex = document.getElementById('asymmetric-decrypt-ciphertext').value;
      const ciphertext = hexToBuffer(ciphertextHex);
      
      try {
        const plaintext = decrypt_asymmetric(ciphertext);
        const decodedText = new TextDecoder().decode(plaintext);
        document.getElementById('asymmetric-decrypt-result').textContent = `Decrypted: ${decodedText}`;
      } catch (e) {
        document.getElementById('asymmetric-decrypt-result').textContent = `Error decrypting: ${e}`;
      }
    } catch (e) {
      document.getElementById('asymmetric-decrypt-result').textContent = `Error: ${e}`;
    }
  });
  
  // Initialize UI
  updateLoginUI();
}

run().catch(console.error);