$('#main-button').click(); // click the "MAIN" button (scrolls up)

setTimeout(changeTexts, 1000); // run after 1 second (to give time to scrolling)

function changeTexts() {
    fade("#title", "Practice coding")
    const action = random(["try", "run", "execute", "modify"])
    const js = link("JavaScript", "https://developer.mozilla.org/docs/Web/JavaScript")
    fade("#text1", "You can " + action  + " the " + js + " code below")
    const functions = join(["fade", "join", "link", "random"]);
    fade("#text2", "Use functions like " + functions)
    fade(".button.run", "Run it again")

    $('#main-section').animate({'min-height': '0'}, 1500); // slowly shrink main section
}

// If you dare, run this. It will load code that, when run, creates an Arkham Horror LGC tracker app.
//fetchCode("https://gist.github.com/fmaylinch/c511180f974da8d352663d4f2e499438/raw");

// You may also try the Arkham Horror LGC tracker with this link: https://bit.ly/arkham-lgc-tracker

// Loads code from url and replaces current code in editor
function fetchCode(url) {
  fetch(url)
    .then(resp => resp.text())
    .then(setCode)
}

// Replaces current code in editor
function setCode(code) {
    codeMirrorEditorView.dispatch({
        changes: { from: 0, to: codeMirrorEditorView.state.doc.length, insert: code },  
    });
}

// Updates a page element, by its CSS selector
function set(selector, value) {
  let element = document.querySelector(selector)
  element.innerHTML = value
}

// It's like set(), but uses jQuery for a fade-in-out effect
function fade(selector, value) {
  let elem = $(selector)
  elem.fadeOut('slow', () => {
    elem.html(value).fadeIn('slow')
  });
}

// Joins the values with commas and "and"
function join(values) {
  if (!Array.isArray(values)) {
    return values
  }
  return values.length === 1
    ? values[0]
    : values.slice(0, values.length-1).join(", ")
      + " and " + values[values.length-1]
}

// Builds an HTML link
function link(text, url) {
  return `<a target="_blank" href="${url}">${text}</a>`
}

// Returns a random number between 0 and n-1.
// If n is an array, returns a random element of n.
function random(n) {
  if (Array.isArray(n)) {
    return n[random(n.length)]
  }
  return Math.floor(Math.random() * n)
}