main.js

  let allMessages = [];
  let chatBox = document.querySelector("#chatBox");
  let newMsgInput = document.querySelector("#newMsg");
  let userName = localStorage.getItem('userName') || "me";
  let userStatus = localStorage.getItem('userStatus') || "update your profile to display a status";
  let userProfilePic = localStorage.getItem('userProfilePic');
  let notifSound = 'for-sure.mp3';
  let notifSoundElement = new Audio(notifSound);
  let usernameDisplay = document.querySelector("#usernameDisplay");
  let userStatusDisplay = document.querySelector("#userStatusDisplay");
  let userProfilePicDisplay = document.querySelector("#userProfilePicDisplay");
  
  usernameDisplay.innerHTML = userName;
  userStatusDisplay.innerHTML = userStatus;
  userProfilePicDisplay.src = userProfilePic;

  function clearChatInput() {
    document.querySelector("#newMsg").value = "";
    document.querySelector("#newMsg").focus();
  }

  function displayNewMessage(msg) {
    var newMsgP = document.createElement("p");
    newMsgP.innerHTML = "<strong>" + msg.sentBy + "</strong>: " + msg.message;
    chatBox.appendChild(newMsgP);
    
    window.navigator.vibrate(200);
    notifSoundElement.play();

    
    chatBox.scrollTop = chatBox.scrollHeight;


    clearChatInput();
  }

  function makeNewMessageFromLocalUser() {
    let usrMsg = {
      sentBy: userName,
      dateStamp: Date.now(),
      message: newMsgInput.value
    }

    if(usrMsg.message !== "") {
      // allMessages.push(usrMsg);
      // // end make message
      // displayNewMessage(usrMsg)
      saveMessageToFirebase(usrMsg);
    }

   
  }

  //** All the triggers and event listener assignments down here... */

  // assign the "Make New Message" function to the button click
  document.querySelector("#sendBtn").addEventListener('click', function(){
    makeNewMessageFromLocalUser()
  });

  // since we're not using a real form, assign it to the "keyup return" of the message input too

  document.querySelector("#newMsg").addEventListener('keyup', function(e) {
    if (e.keyCode === 13) {
        makeNewMessageFromLocalUser();
    }
  });