(function () {
'use strict';

/* ================================================================== helpers */
var $ = function (id) { return document.getElementById(id); };
function el(tag, cls, text) {
  var e = document.createElement(tag);
  if (cls) e.className = cls;
  if (text !== undefined && text !== null) e.textContent = text;
  return e;
}
function clear(n) { while (n.firstChild) n.removeChild(n.firstChild); }
function plural(n, w) { return n + ' ' + w + (n === 1 ? '' : 's'); }
function basename(p) { var i = p.lastIndexOf('/'); return i < 0 ? p : p.slice(i + 1); }
function dirname(p) { var i = p.lastIndexOf('/'); return i < 0 ? '' : p.slice(0, i); }
function joinPath(d, n) { return d ? d + '/' + n : n; }
function stem(n) { var i = n.lastIndexOf('.'); return i <= 0 ? n : n.slice(0, i); }
function isGrammarFile(p) { return /\.g4$/i.test(p); }
function human(n) { return n < 1024 ? n + ' B' : n < 1048576 ? (n / 1024).toFixed(1) + ' KB' : (n / 1048576).toFixed(1) + ' MB'; }

var store = {
  get: function (k, d) {
    try { var v = localStorage.getItem('antlrlab:' + k); return v === null ? d : JSON.parse(v); } catch (e) { return d; }
  },
  set: function (k, v) { try { localStorage.setItem('antlrlab:' + k, JSON.stringify(v)); } catch (e) { /* ignore */ } }
};

function debounce(fn, ms) {
  var t = null;
  var d = function () { clearTimeout(t); var a = arguments; t = setTimeout(function () { fn.apply(null, a); }, ms); };
  d.cancel = function () { clearTimeout(t); };
  return d;
}

/* ==================================================================== state */
var S = {
  info: null,
  tabs: [],
  active: null,        // id of the visible tab
  lastGrammar: null,   // the grammar that Run uses
  lastInput: null,     // the input that Run uses
  results: {},         // input tab id -> { data, rev, grev }
  gres: null,          // last grammar outcome from the server
  crash: null,         // set when the last run crashed, timed out or failed in the worker
  grev: 0,             // bumps on every grammar edit
  start: {},           // grammar name -> chosen start rule
  prefs: { autorun: true, theme: 'auto', fs: 13, diagram: true, output: true, view: 'diagram', out: 'problems' },
  running: false,
  queued: false,
  untitled: { grammar: 0, input: 0 }
};

/* ====================================================================== API */
function api(method, path, body) {
  var opts = { method: method, credentials: 'same-origin', headers: { 'X-Requested-With': 'antlrlab' } };
  if (body !== undefined) {
    opts.body = JSON.stringify(body);
    opts.headers['Content-Type'] = 'application/json';
  }
  return fetch(path, opts).then(function (r) {
    return r.text().then(function (t) {
      var data = null;
      try { data = JSON.parse(t); } catch (e) { /* not JSON */ }
      if (!r.ok) {
        var err = new Error((data && data.error) || ('HTTP ' + r.status));
        err.status = r.status;
        err.data = data;
        throw err;
      }
      return data;
    });
  });
}

/* ==================================================================== toast */
function toast(msg, kind) {
  var t = el('div', 'toast' + (kind ? ' ' + kind : ''), msg);
  $('toasts').appendChild(t);
  setTimeout(function () { if (t.parentNode) t.parentNode.removeChild(t); }, kind === 'error' ? 6500 : 2600);
}

/* ================================================================== dialogs */
// modal({title, build(ctx) -> Node, buttons: [{label, value, primary}]}) -> Promise(value | null)
function modal(opts) {
  return new Promise(function (resolve) {
    var root = $('modal-root');
    var prev = document.activeElement;
    clear(root);
    var back = el('div', 'modal-back');
    var box = el('div', 'modal');
    box.setAttribute('role', 'dialog');
    box.setAttribute('aria-modal', 'true');
    box.appendChild(el('h3', '', opts.title));
    var body = el('div', 'mbody');
    var ctx = { close: close, box: box, accept: null };
    if (opts.message) body.appendChild(el('p', '', opts.message));
    if (opts.build) body.appendChild(opts.build(ctx));
    box.appendChild(body);
    var foot = el('div', 'mfoot');
    var primary = null;
    (opts.buttons || []).forEach(function (b) {
      var btn = el('button', 'btn' + (b.primary ? ' primary' : ''), b.label);
      btn.type = 'button';
      btn.onclick = function () {
        if (b.check && !b.check()) return;
        close(b.value === undefined ? b.label : b.value);
      };
      if (b.primary) primary = btn;
      foot.appendChild(btn);
    });
    box.appendChild(foot);
    back.appendChild(box);
    root.appendChild(back);

    function onKey(ev) {
      if (ev.key === 'Escape') { ev.preventDefault(); ev.stopPropagation(); close(null); }
      else if (ev.key === 'Enter' && primary && ev.target.tagName !== 'BUTTON' && !(ev.target.closest && ev.target.closest('.flist'))) {
        ev.preventDefault();
        ev.stopPropagation();
        primary.click();
      }
    }
    back.addEventListener('mousedown', function (ev) { if (ev.target === back) close(null); });
    document.addEventListener('keydown', onKey, true);
    function close(v) {
      document.removeEventListener('keydown', onKey, true);
      clear(root);
      if (prev && prev.focus) prev.focus();
      resolve(v);
    }
    var first = box.querySelector('[data-focus]') || primary || box.querySelector('button');
    if (first) first.focus();
  });
}

function ask(title, message, buttons) { return modal({ title: title, message: message, buttons: buttons }); }

/* ===================================================================== menus */
var menus = [];      // [{label, items: function() -> [...]}]
var openMenu = -1;
var dropdown = null;

function defineMenus(list) {
  menus = list;
  var bar = $('menubar');
  clear(bar);
  menus.forEach(function (m, i) {
    var b = el('button', 'menu-btn', m.label);
    b.type = 'button';
    b.setAttribute('role', 'menuitem');
    b.setAttribute('aria-haspopup', 'true');
    b.setAttribute('aria-expanded', 'false');
    b.onclick = function () { if (openMenu === i) closeMenu(); else showMenu(i, false); };
    b.onmouseenter = function () { if (openMenu >= 0 && openMenu !== i) showMenu(i, false); };
    b.onkeydown = function (ev) {
      if (ev.key === 'ArrowDown' || ev.key === 'Enter' || ev.key === ' ') { ev.preventDefault(); showMenu(i, true); }
      else if (ev.key === 'ArrowRight') { ev.preventDefault(); bar.children[(i + 1) % menus.length].focus(); }
      else if (ev.key === 'ArrowLeft') { ev.preventDefault(); bar.children[(i + menus.length - 1) % menus.length].focus(); }
    };
    bar.appendChild(b);
  });
  var rn = el('span', '', '');
  rn.id = 'rootname';
  bar.appendChild(rn);
}

function closeMenu(refocus) {
  if (dropdown) { dropdown.remove(); dropdown = null; }
  var bar = $('menubar');
  Array.prototype.forEach.call(bar.querySelectorAll('.menu-btn'), function (b) { b.setAttribute('aria-expanded', 'false'); });
  var was = openMenu;
  openMenu = -1;
  if (refocus && was >= 0) bar.children[was].focus();
}

function showMenu(i, focusFirst) {
  closeMenu();
  openMenu = i;
  var btn = $('menubar').children[i];
  btn.setAttribute('aria-expanded', 'true');
  var dd = el('div', 'dropdown');
  dd.setAttribute('role', 'menu');
  menus[i].items().forEach(function (it) {
    if (it.sep) { dd.appendChild(el('div', 'sep')); return; }
    var row = el('div', 'mi');
    row.setAttribute('role', 'menuitem');
    row.tabIndex = -1;
    if (it.disabled) row.setAttribute('aria-disabled', 'true');
    if (it.checked) { row.appendChild(el('span', 'ck', '\u2713')); row.setAttribute('aria-checked', 'true'); }
    row.appendChild(el('span', '', it.label));
    if (it.key) row.appendChild(el('span', 'k', it.key));
    var run = function () { closeMenu(); setTimeout(it.action, 0); };
    row.onclick = run;
    row.onkeydown = function (ev) {
      var items = Array.prototype.filter.call(dd.children, function (c) { return c.classList.contains('mi') && c.getAttribute('aria-disabled') !== 'true'; });
      var at = items.indexOf(row);
      if (ev.key === 'ArrowDown') { ev.preventDefault(); items[(at + 1) % items.length].focus(); }
      else if (ev.key === 'ArrowUp') { ev.preventDefault(); items[(at + items.length - 1) % items.length].focus(); }
      else if (ev.key === 'Enter' || ev.key === ' ') { ev.preventDefault(); run(); }
      else if (ev.key === 'Escape') { ev.preventDefault(); closeMenu(true); }
      else if (ev.key === 'ArrowRight' || ev.key === 'ArrowLeft') {
        ev.preventDefault();
        var n = (i + (ev.key === 'ArrowRight' ? 1 : menus.length - 1)) % menus.length;
        showMenu(n, true);
        $('menubar').children[n].focus();
        var first = dropdown && dropdown.querySelector('.mi:not([aria-disabled=true])');
        if (first) first.focus();
      }
    };
    dd.appendChild(row);
  });
  document.body.appendChild(dd);
  var r = btn.getBoundingClientRect();
  dd.style.left = Math.max(0, Math.min(r.left, window.innerWidth - dd.offsetWidth - 4)) + 'px';
  dd.style.top = r.bottom + 'px';
  dropdown = dd;
  if (focusFirst) {
    var f = dd.querySelector('.mi:not([aria-disabled=true])');
    if (f) f.focus();
  }
}

document.addEventListener('mousedown', function (ev) {
  if (dropdown && !dropdown.contains(ev.target) && !ev.target.closest('.menu-btn')) closeMenu();
});
window.addEventListener('blur', function () { closeMenu(); });