export let warn = () => { };
export let tip = () => { };

if (process.env.NODE_ENV !== 'production')
{
  warn = (msg, vm) =>
  {
    const trace = vm ? generateComponentTrace(vm) : '';
    console.error(`[zero warn]: ${msg}${trace}`);
  };


  tip = (msg, vm) =>
  {
    const trace = vm ? generateComponentTrace(vm) : '';
    console.warn(`[zero tip]: ${msg}${trace}`);
  };


  let generateComponentTrace = vm =>
  {
    if (vm._isVue && vm.$parent)
    {
      const tree = [];
      let currentRecursiveSequence = 0;
      while (vm)
      {
        if (tree.length > 0)
        {
          const last = tree[tree.length - 1];
          if (last.constructor === vm.constructor)
          {
            currentRecursiveSequence++;
            vm = vm.$parent;
            continue;
          } else if (currentRecursiveSequence > 0)
          {
            tree[tree.length - 1] = [last, currentRecursiveSequence];
            currentRecursiveSequence = 0;
          }
        }
        tree.push(vm);
        vm = vm.$parent;
      }
      return '\n\nfound in\n\n' + tree
        .map((vm, i) => `${
          i === 0 ? '---> ' : repeat(' ', 5 + i * 2)
          }${
          Array.isArray(vm)
            ? `${formatComponentName(vm[0])}... (${vm[1]} recursive calls)`
            : formatComponentName(vm)
          }`)
        .join('\n');
    } else
    {
      return `\n\n(found in ${formatComponentName(vm)})`;
    }
  };


  let formatComponentName = (vm, includeFile) =>
  {
    if (vm.$root === vm)
    {
      return '<Root>';
    }
    const options = typeof vm === 'function' && vm.cid
      ? vm.options
      : vm._isVue
        ? vm.$options || vm.constructor.options
        : vm;
    let name = options.name || options._componentTag;
    const file = options.__file;
    if (!name && file)
    {
      const match = file.match(/([^/\\]+)\.vue$/);
      name = match && match[1];
    }

    return (
      (name ? `<${classify(name)}>` : `<Anonymous>`) +
      (file && includeFile !== false ? ` at ${file}` : '')
    );
  };

  const repeat = (str, n) =>
  {
    let res = '';
    while (n)
    {
      if (n % 2 === 1) res += str;
      if (n > 1) str += str;
      n >>= 1;
    }
    return res;
  };
}