/**
 * 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.
 *
 * @typechecks static-only
 * @providesModule ReactServerRendering
 */
"use strict";

var ReactDescriptor = require('ReactDescriptor');
var ReactInstanceHandles = require('ReactInstanceHandles');
var ReactMarkupChecksum = require('ReactMarkupChecksum');
var ReactServerRenderingTransaction =
  require('ReactServerRenderingTransaction');

var instantiateReactComponent = require('instantiateReactComponent');
var invariant = require('invariant');

/**
 * @param {ReactComponent} component
 * @return {string} the HTML markup
 */
function renderComponentToString(component) {
  invariant(
    ReactDescriptor.isValidDescriptor(component),
    'renderComponentToString(): You must pass a valid ReactComponent.'
  );

  invariant(
    !(arguments.length === 2 && typeof arguments[1] === 'function'),
    'renderComponentToString(): This function became synchronous and now ' +
    'returns the generated markup. Please remove the second parameter.'
  );

  var transaction;
  try {
    var id = ReactInstanceHandles.createReactRootID();
    transaction = ReactServerRenderingTransaction.getPooled(false);

    return transaction.perform(function() {
      var componentInstance = instantiateReactComponent(component);
      var markup = componentInstance.mountComponent(id, transaction, 0);
      return ReactMarkupChecksum.addChecksumToMarkup(markup);
    }, null);
  } finally {
    ReactServerRenderingTransaction.release(transaction);
  }
}

/**
 * @param {ReactComponent} component
 * @return {string} the HTML markup, without the extra React ID and checksum
* (for generating static pages)
 */
function renderComponentToStaticMarkup(component) {
  invariant(
    ReactDescriptor.isValidDescriptor(component),
    'renderComponentToStaticMarkup(): You must pass a valid ReactComponent.'
  );

  var transaction;
  try {
    var id = ReactInstanceHandles.createReactRootID();
    transaction = ReactServerRenderingTransaction.getPooled(true);

    return transaction.perform(function() {
      var componentInstance = instantiateReactComponent(component);
      return componentInstance.mountComponent(id, transaction, 0);
    }, null);
  } finally {
    ReactServerRenderingTransaction.release(transaction);
  }
}

module.exports = {
  renderComponentToString: renderComponentToString,
  renderComponentToStaticMarkup: renderComponentToStaticMarkup
};
