(function() {
  this.ReactOnRails = {};

  ReactOnRails.clientRenderReactComponent = function(options) {
    var componentName = options.componentName;
    var domId = options.domId;
    var propsVarName = options.propsVarName;
    var props = options.props;
    var trace = options.trace;
    var generatorFunction = options.generatorFunction;
    var expectTurboLinks = options.expectTurboLinks;

    this[propsVarName] = props;

    var renderIfDomNodePresent = function() {
      try {
        var domNode = document.getElementById(domId);
        if (domNode) {
          var reactElement = createReactElement(componentName, propsVarName, props,
            domId, trace, generatorFunction);
          React.render(reactElement, domNode);
        }
      }
      catch (e) {
        handleError(e, componentName);
      }
    };

    var turbolinksInstalled = typeof(Turbolinks) !== 'undefined';
    if (!expectTurboLinks || (!turbolinksInstalled && expectTurboLinks)) {
      if (expectTurboLinks) {
        console.warn("WARNING: NO TurboLinks detected in JS, but it's in your Gemfile");
      }
      document.addEventListener("DOMContentLoaded", function(event) {
        renderIfDomNodePresent();
      });
    } else {
      function onPageChange(event) {
        var removePageChangeListener = function() {
          document.removeEventListener("page:change", onPageChange);
          document.removeEventListener("page:before-unload", removePageChangeListener);
          var domNode = document.getElementById(domId);
          React.unmountComponentAtNode(domNode);
        };
        document.addEventListener("page:before-unload", removePageChangeListener);

        renderIfDomNodePresent();
      }

      document.addEventListener("page:change", onPageChange);
    }
  };

  ReactOnRails.serverRenderReactComponent = function(options) {
    var componentName = options.componentName;
    var domId = options.domId;
    var propsVarName = options.propsVarName;
    var props = options.props;
    var trace = options.trace;
    var generatorFunction = options.generatorFunction;

    var htmlResult = '';
    var consoleReplay = '';

    try {
      var reactElement = createReactElement(componentName, propsVarName, props,
        domId, trace, generatorFunction);
      htmlResult = React.renderToString(reactElement);
    }
    catch (e) {
      htmlResult = handleError(e, componentName);
    }

    consoleReplay = ReactOnRails.buildConsoleReplay();
    return JSON.stringify([htmlResult, consoleReplay]);
  };

  function createReactElement(componentName, propsVarName, props, domId, trace, generatorFunction) {
    if (trace) {
      console.log('RENDERED ' + componentName + ' with data_variable ' +
        propsVarName + ' to dom node with id: ' + domId);
    }

    if (generatorFunction) {
      return this[componentName](props);
    } else {
      return React.createElement(this[componentName], props);
    }
  }

  // Passing either componentName or jsCode
  function handleError(e, componentName, jsCode) {
    var lineOne =
      'ERROR: You specified the option generator_function (could be in your defaults) to be\n';
    var lastLine =
      'A generator function takes a single arg of props and returns a ReactElement.';

    console.error('Exception in rendering!');

    var msg = '';
    if (componentName) {
      var shouldBeGeneratorError = lineOne +
        'false, but the React component \'' + componentName + '\' seems to be a generator function.\n' +
        lastLine;
      var reMatchShouldBeGeneratorError = /Can't add property context, object is not extensible/;
      if (reMatchShouldBeGeneratorError.test(e.message)) {
        msg += shouldBeGeneratorError + '\n\n';
        console.error(shouldBeGeneratorError);
      }

      var shouldBeGeneratorError = lineOne +
        'true, but the React component \'' + componentName + '\' is not a generator function.\n' +
        lastLine;
      var reMatchShouldNotBeGeneratorError = /Cannot call a class as a function/;
      if (reMatchShouldNotBeGeneratorError.test(e.message)) {
        msg += shouldBeGeneratorError + '\n\n';
        console.error(shouldBeGeneratorError);
      }
    }

    if (jsCode) {
      console.error('JS code was: ' + jsCode);
    }

    if (e.fileName) {
      console.error('location: ' + e.fileName + ':' + e.lineNumber);
    }
    console.error('message: ' + e.message);
    console.error('stack: ' + e.stack);
    msg += 'Exception in rendering!\n' +
      (e.fileName ? '\nlocation: ' + e.fileName + ':' + e.lineNumber : '') +
      '\nMessage: ' + e.message + '\n\n' + e.stack;

    var reactElement = React.createElement('pre', null, msg);
    return React.renderToString(reactElement);
  }

  ReactOnRails.buildConsoleReplay = function() {
    var consoleReplay = '';

    var history = console.history;
    if (history && history.length > 0) {
      consoleReplay += '\n<script>';
      history.forEach(function(msg) {
        consoleReplay += '\nconsole.' + msg.level + '.apply(console, ' +
          JSON.stringify(msg.arguments) + ');';
      });
      consoleReplay += '\n</script>';
    }

    return consoleReplay;
  }
}.call(this));