/*
 * tabcompletion, emotes and usernames
 * also overwrite native tabcompletion
*/

$('#chatline').unbind('keydown',tabSuggestions || function(){});
var tabSuggestions = (function(){

    var chatline = document.getElementById('chatline'),
        suggestionsDiv = document.getElementById('suggestionsDiv') || document.createElement('div'),
        lastMatchNum = 0,
        lastMatch;
    suggestionsDiv.id = 'suggestionsDiv',
    suggestionsDiv.style.position = 'absolute',
    suggestionsDiv.style.zIndex = '999',
    suggestionsDiv.style.backgroundColor = '#161a20',
    chatline.parentNode.appendChild(suggestionsDiv)

    function emoteImg(emote){
        var i = document.createElement('img')
        i.className = 'channel-emote',
        i.src = emote.image,
        i.title = emote.name,
        i.onclick = function(e){
            clearBorders();
            chatline.value = chatline.value.replace(/\/[a-z0-9?!&]*$/i, emote.name),
            // als er geen spatie of dubbele punt voor de /emote staat, voeg een spatie toe (anders werkt de emote niet)
            chatline.value.lastIndexOf('/') !== 0 && // check eerst of de / niet het eerste teken van de string is
            [' ',':'].indexOf(chatline.value[chatline.value.lastIndexOf('/')-1]) === -1 && // staat er iets anders dan een spatie of : voor de /emote ?
            (chatline.value = chatline.value.replace(/\/[a-z0-9?!&]*$/i, ' ' + emote.name)), // zet een spatie voor de /emote
            this.style.border = '2px solid white',
            chatline.focus();
            var i = 0, a = this;
            while (a = a.previousSibling) i++;
            lastMatchNum = i
        }
        return i
    }

    function clearBorders(){
        for (var i = 0; i < suggestionsDiv.children.length; i++)
            suggestionsDiv.children[i].style.border = 'none'
    }

    function levenshtein(a, b) {
      if (a.length === 0) return b.length
      if (b.length === 0) return a.length
      let tmp, i, j, prev, val, row
      // swap to save some memory O(min(a,b)) instead of O(a)
      if (a.length > b.length) {
        tmp = a
        a = b
        b = tmp
      }

      row = Array(a.length + 1)
      // init the row
      for (i = 0; i <= a.length; i++) {
        row[i] = i
      }

      // fill in the rest
      for (i = 1; i <= b.length; i++) {
        prev = i
        for (j = 1; j <= a.length; j++) {
          if (b[i - 1] === a[j - 1]) {
            val = row[j - 1] // match
          } else {
            val = Math.min(row[j - 1] + 1, // substitution
                  Math.min(prev + 1,     // insertion
                           row[j] + 1))  // deletion
          }
          row[j - 1] = prev
          prev = val
        }
        row[a.length] = prev
      }
      return row[a.length]
    }

    return function(e){
        if (e.keyCode != 9 && !e.shiftKey)
            suggestionsDiv.innerHTML = '',
            lastMatch = null
        else if (e.keyCode == 9){
            //emotes
            if (lastMatch) {
                //toggle matches
                if (Object.prototype.toString.call(lastMatch) === '[object Array]')
                    //usernames
                    chatline.value = chatline.value.replace(/[a-z0-9-]+$/i, lastMatch[++lastMatchNum % lastMatch.length])
                else
                    //emotes
                    e.shiftKey ? lastMatchNum = (--lastMatchNum + suggestionsDiv.children.length) % suggestionsDiv.children.length :
                    lastMatchNum = ++lastMatchNum % suggestionsDiv.children.length,
                    clearBorders(),suggestionsDiv.children[lastMatchNum] && suggestionsDiv.children[lastMatchNum].onclick()
            } else {

                var emoteStr = chatline.value.match(/\/[a-z0-9?!&]*$/i)
                if (emoteStr){
                    //show emotesuggestions
                    var emoteList = CHANNEL.emotes.slice(),
                        suggestions = []
                    //find matches based on levenshtein distance
                    emoteStr = emoteStr[0].replace(/\?/g,'\\?')
                    for (var i = 0, emoteStr_withoutslash = emoteStr.replace('/',''); i < emoteList.length; i++)
                        if (emoteList[i].name.match(emoteStr_withoutslash) || levenshtein(emoteStr, emoteList[i].name) < 3)
                            suggestions.push(new emoteImg(emoteList[i]))
                    //sort suggestions
                    suggestions.sort(function(a, b){
                        var indexofa = a.title.indexOf(emoteStr),
                            indexofb = b.title.indexOf(emoteStr)

                        if (indexofa === 0 && indexofb !== 0)
                            return -1
                        else if (indexofb === 0 && indexofa !== 0)
                            return 1
                        else {
                            //sort aphabetically with respect for numbers at the end
                            var i = 0;
                            while (a.title.charAt(i) === b.title.charAt(i) && i < a.title.length && i < b.title.length)
                                i++;
                            if (a.title.length !== b.title.length &&
                               (i == a.title.length - 1 || i == b.title.length - 1) &&
                               !isNaN(parseInt(a.title.charAt(i))) && !isNaN(parseInt(b.title.charAt(i))))
                                return a.title.charAt(i) < b.title.charAt(i) ? 1 : -1
                            return a.title.charAt(i) < b.title.charAt(i) ? -1 : 1
                        }
                    })
                    //populate suggestionsDiv
                    suggestionsDiv.innerHTML = ''
                    for (var i=0; i<suggestions.length; i++)
                        suggestionsDiv.appendChild(suggestions[i])
                    lastMatchNum = 0,
                    lastMatch = emoteStr,
                    suggestionsDiv.children[0] && (suggestionsDiv.children[0].style.border = '2px solid white') && suggestionsDiv.children[lastMatchNum].onclick()

                } else {
                    //usernames
                    var userStr = chatline.value.match(/[a-z0-9-]+$/i),
                        userlistElems = $('#userlist .userlist_item');//document.getElementById("userlist").children
                    lastMatch = [],
                    lastMatchNum = 0
                    for (var i = 0; i < userlistElems.length; i++)
                        if (userlistElems[i].children[1].textContent != CLIENT.name &&
                            userlistElems[i].children[1].textContent.match(new RegExp('^' + userStr, 'i')))
                            lastMatch.push(userlistElems[i].children[1].textContent);
                    if (lastMatch.length != 0)
                        chatline.value = chatline.value.replace(/[a-z0-9-]+$/i, lastMatch[0])
                    else
                        lastMatch = null
                }
            }
        }
    }
})()

chatTabComplete = function(){return false},
$("#chatline").keydown(tabSuggestions)