interacting with HTML retreived from localStorage (via JSON)

document.addEventListener('DOMContentLoaded', () => {
  const form = document.getElementById('registrar');
  const input = form.querySelector('input');

  const mainDiv = document.querySelector('.main');
  const ul = document.getElementById('invitedList');

  const div = document.createElement('div');
  const filterLabel = document.createElement('label');
  const filterCheckBox = document.createElement('input');


  filterLabel.textContent = "Hide those who haven't responded";
  filterCheckBox.type = 'checkbox';
  div.appendChild(filterLabel);
  div.appendChild(filterCheckBox);
  mainDiv.insertBefore(div, ul);

  if (localStorage.invitees) {
    ul.outerHTML = JSON.parse(localStorage.invitees);
  }


  filterCheckBox.addEventListener('change', (e) => {
    const isChecked = e.target.checked;
    const lis = ul.children;
    if(isChecked) {
      for (let i = 0; i < lis.length; i += 1) {
        let li = lis[i];
        if (li.className === 'responded') {
          li.style.display = '';
          // Hide the checkbox and label for confirmed invitees when
          // filter is activated
          li.getElementsByTagName('label')[0].style.display = 'none';
          // console.log(li.getElementsByTagName('label')[0]);
        } else {
          li.style.display = 'none';
        }
      }
    } else {
      for (let i = 0; i < lis.length; i += 1) {
        let li = lis[i];
        li.style.display = '';
        // Show checkbox and label again when filter is removed
        li.getElementsByTagName('label')[0].style.display = '';
      }
    }
  });

  function createLI(text) {
    function createElement(elementName, property, value) {
      const element = document.createElement(elementName);
      element[property] = value;
      return element;
    }

    function appendToLI(elementName, property, value) {
      const element = createElement(elementName, property, value);
      li.appendChild(element);
      return element;
    }

    const li = document.createElement('li');
    appendToLI('span', 'textContent', text);
    appendToLI('label', 'textContent', 'Confirm?')
      .appendChild(createElement('input', 'type', 'checkbox'));
    appendToLI('button', 'textContent', 'edit');
    appendToLI('button', 'textContent', 'remove');
    return li;
  }

  form.addEventListener('submit', (e) => {
    e.preventDefault();
    const text = input.value;
    // disallow duplicate names for invitees
    let duplicate = false;
    if (ul.children.length > 0) {
      for (i = 0; i < ul.children.length; i++) {
        if (text.toLowerCase() === ul.children[i].firstElementChild.textContent.toLowerCase()) {
          duplicate = true;
          console.log(duplicate);
        }
      }
    }
    // check for empty string and disallow
    if (text === '') {
      alert('Please enter a valid name');
    } else if (duplicate) {   // check for duplicate names
      alert("Duplicate names not allowed");
      duplicate = false;
    } else {
      input.value = '';
      const li = createLI(text);
      ul.appendChild(li);

      // store ul in localStorage
      console.log(ul.outerHTML);
      localStorage.setItem('invitees', JSON.stringify(ul.outerHTML));
    }

  });

  ul.addEventListener('change', (e) => {
    const checkbox = event.target;
    const checked = checkbox.checked;
    const listItem = checkbox.parentNode.parentNode;
    const label = checkbox.parentNode;

    if (checked) {
      listItem.className = 'responded';
      label.childNodes[0].nodeValue = 'Confirmed';
    } else {
      listItem.className = '';
      label.childNodes[0].nodeValue = 'Confirm?';
    }
  });

  ul.addEventListener('click', (e) => {
    if (e.target.tagName === 'BUTTON') {
      const button = e.target;
      const li = button.parentNode;
      const ul = li.parentNode;
      const action = button.textContent;
      const nameActions = {
        remove: () => {
          ul.removeChild(li);
        },
        edit: () => {
          const span = li.firstElementChild;
          const input = document.createElement('input');
          input.type = 'text';
          input.value = span.textContent;
          li.insertBefore(input, span);
          li.removeChild(span);
          button.textContent = 'save';
        },
        save: () => {
          const input = li.firstElementChild;
          const span = document.createElement('span');
          span.textContent = input.value;
          li.insertBefore(span, input);
          li.removeChild(input);
          button.textContent = 'edit';
        }
      };

      // select and run action in button's name
      nameActions[action]();
    }
  });


});