/**
 * Copyright 2013-2014 Facebook, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*global exports:true*/
"use strict";
var Syntax = require('esprima-fb').Syntax;
var utils = require('jstransform/src/utils');

function renderXJSLiteral(object, state) {
  var value = object.raw;

  utils.catchup(object.range[0], state);

  /*
    This can be used to "annotate spaces" inserted by this transformation,
    so that they can be more easily recognized as such in the final code

    {' '}
    {'\\x20'}
    {(' ')}
    {' '||0}
    {' '||AnyTextYouLike}
    {' '||'AnyTextYouLike'}
    {GlobalVariableWithASpace}
  */

  var space = "{' '}";

  /*
    · space
    ¬ newline
    {expr} = <tag>

    Old whitespace rules:
    {1}··Aaa··Bbb··{2}··{3}  →  {1}·Aaa··Bbb·{2}{3}
    {1}¬¬Aaa¬¬Bbb¬¬{2}¬¬{3}  →  {1}·Aaa·Bbb·{2}{3}

    New whitespace rules:
    {1}··Aaa··Bbb··{2}··{3}  →  {1}··Aaa··Bbb··{2}··{3}
    {1}¬¬Aaa¬¬Bbb¬¬{2}¬¬{3}  →  {1}Aaa·Bbb{2}{3}

    Required transformation:
    {1}··{2}       =  {1}··{2}       →  {1}{2}
    {1}··Aaa··{2}  =  {1}··Aaa··{2}  →  {1}·Aaa·{2}
    {1}¬¬Aaa¬¬{2}  =  {1}Aaa{2}      →  {1}·Aaa·{2}
  */

  // {1}··{2}  =  {1}··{2}  →  {1}{2}
  value = value.replace(/^[ \t]+$/, '');

  // {1}··Aaa··{2}  =  {1}··Aaa··{2}  →  {1}·Aaa·{2}
  value = value.replace(/^[ \t]+([^ \t\r\n])/, " $1");
  value = value.replace(/([^ \t\r\n])[ \t]+$/, "$1 ");

  // {1}¬¬Aaa¬¬{2}  =  {1}Aaa{2}  →  {1}·Aaa·{2}
  value = value.replace(/^([ \t]*[\r\n][ \t\r\n]*)([^ \t\r\n].*)/, "$1" + space + "$2");
  value = value.replace(/([^ \t\r\n])([ \t]*[\r\n][ \t\r\n]*)$/, "$1" + space + "$2");

  // Rendered whitespace tabs are replaced with spaces
  value = value.replace(/[^ \t\r\n][ ]*[\t][ \t]*[^ \t\r\n]/, function(match) {
    return match.replace(/\t/g, ' ');
  });

  utils.append(value, state);
  utils.move(object.range[1], state);
}

function renderXJSExpressionContainer(
  traverse, object,
  isNotAfterLiteral,
  isNotBeforeLiteral,
  path, state)
{
  utils.catchup(object.range[0], state);

  // Unbox the previously required {' '}-workaround
  var raw = object.expression.raw;
  var isSpace = (raw === "' '" || raw === '" "');

  if (isNotAfterLiteral && isNotBeforeLiteral && isSpace) {
    utils.append(' ', state);
    utils.move(object.range[1], state);
  } else {
    utils.catchup(object.range[1], state);
  }

  return false;
}

exports.renderXJSExpressionContainer = renderXJSExpressionContainer;
exports.renderXJSLiteral = renderXJSLiteral;