const form = document.querySelector('#login_form');
const username_field = form.querySelector('#username');
const password_field = form.querySelector('#password');
const password_hash_field = form.querySelector('#password_hash');
const submit_button = form.querySelector('input[type="submit"]');

submit_button.addEventListener('click', async (e) => {
  e.preventDefault();
  const password_hash = await hashString(password_field.value);
  const urlParams = new URLSearchParams(document.location.search);
  const redirect = decodeURI(urlParams.get('redirect'));
  requestAuth(username_field.value, password_hash, redirect);
});

function requestAuth(username, password_hash, redirect) {
  fetch('http://localhost:7477/auth', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
    },
    body: 'username=' + username + '&password_hash=' + password_hash,
  })
    .then(response => {
      if (!response.ok) {
        console.log('Login Failed!');
      }

      return response.json(); // Parse response body as JSON
    })
    .then(data => {
      notifyServer(data["id"], username, 1, redirect);
    });
}

function notifyServer(id, username, role, redirect) {
  fetch('director.php', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
    },
    body: 'ajax_id=login&user_id=' + id + '&username=' + username + '&role=' + role,
  })
    .then(response => {
      return response.json();
    })
    .then(data => {
      if ('startViewTransition' in document) {
        document.startViewTransition(() => {
          if (redirect == null) {
            window.location.href = 'articles.php?view=list&sort=new';
          } else {
            window.location.href = redirect;
          }
        });
      } else {
        // Fallback for browsers that don't support View Transitions
        if (redirect == null) {
          window.location.href = 'articles.php?view=list&sort=new';
        } else {
          window.location.href = redirect;
        }
      }
    });
}

async function hashString(str) {
  const encoded = new TextEncoder().encode(str);
  const digest = await crypto.subtle.digest('SHA-256', encoded);
  const hashArray = Array.from(new Uint8Array(digest));
  const hashHex = hashArray.map(byte => byte.toString(16).padStart(2, '0')).join('');
  return hashHex;
}