/* Client-side part of StreamGoose */

/* escape HTML entities (for non-server-provided stuff) */
function esc(s) {
  return s.replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;')
          .replace(/"/g,'&quot;').replace(/'/g,'&apos;')
}

/* handle Twitch and YouTube emotes */
function handleEmotes(text) {
  var url = 'https://static-cdn.jtvnw.net/emoticons/v2/$id/default/dark/1.0'
  /* Handle Twitch emotes coming from backends */
  text = text.replace(/#EMOTE-[^\s]+#/g,
    a=>'<img src="' + url.replace('$id', a.split('-')[1].slice(0,-1)) + '">')
  /* Handle YouTube emotes */
  text = text.replace(/:[^\s]+:/g, a => {
    if(YT_EMOTES.indexOf(a) > -1) /* found in the database */
      return '<img src="/img/yt-emotes/' + a + '.png">'
    else return a
  })
  return text
}

/* detect if there are any overridden styles */
function overrideStyles(text) {
  var styles = '', re
  if(messageHighlightRules) {
    for(re in messageHighlightRules) {
      if((new RegExp(re, 'iu')).test(text))
        styles += 'color:' + messageHighlightRules[re] + ';'
    }
  }
  if(styles.length > 0) styles = ' style="' + esc(styles) + '"'
  return styles
}

/* individual message appender */
function gooseAppendMessage(id, type, timestamp, username, text, icon) {
  var html = ""
  if(parseInt(id) > 0 && type.length > 0) {
    var classes = type.split('-'), cl = classes.length, j,
        colorpref = null
    for(j=0;j<cl;j++) { /* detect color preference */
      if(classes[j].startsWith('color'))
        colorpref = classes[j].slice(5) /* remove color word */
    }
    html += '<div data-msg-id="' + id + '" class="' + classes.join(' ') +'">'
    if(icon.length > 0)
      html += '<span class=icon><img src="' + icon + '"></span>'
    html += '<span class=timestamp>' + timestamp + '</span>'
    html += '<span class=username'
    if(colorpref) html += ' style="color:' + colorpref + '"'
    html += '>' + username + '</span>'
    html += '<span class=msg' + overrideStyles(text) +'>' + handleEmotes(text) + '</span></div>'
  }
  document.getElementById("msglist").innerHTML += html
  /* autoscroll to the end */
  window.scrollTo(0, document.body.scrollHeight)
}

/* entry point, set up an event source */
window.addEventListener('DOMContentLoaded', function() {
  var msgSource = new EventSource('/sse')
  msgSource.onmessage = e => {
    var msg = JSON.parse(e.data)
    gooseAppendMessage(msg.id, msg.type, msg.timestamp, msg.username, msg.text, msg.icon)
  }
}, false)