// Copyright IBM Corp. 2016. All Rights Reserved.
  // Node module: strong-error-handler
  // This file is licensed under the MIT License.
  // License text available at https://opensource.org/licenses/MIT
  
  'use strict';
  var ejs = require('ejs');
  var fs = require('fs');
  var path = require('path');
  
  var assetDir = path.resolve(__dirname, '../views');
  var compiledTemplates = {
    // loading default template and stylesheet
    default: loadDefaultTemplates(),
  };
  
  module.exports = sendHtml;
  
  function sendHtml(res, data, options) {
    var toRender = {options: {}, data: data};
    // TODO: ability to call non-default template functions from options
    var body = compiledTemplates.default(toRender);
    sendReponse(res, body);
  }
  
  /**
   * Compile and cache the file with the `filename` key in options
   *
   * @param filepath (description)
   * @returns {Function} render function with signature fn(data);
   */
  function compileTemplate(filepath) {
    var options = {cache: true, filename: filepath};
    var fileContent = fs.readFileSync(filepath, 'utf8');
    return ejs.compile(fileContent, options);
  }
  
  // loads and cache default error templates
  function loadDefaultTemplates() {
    var defaultTemplate = path.resolve(assetDir, 'default-error.ejs');
    return compileTemplate(defaultTemplate);
  }
  
  function sendReponse(res, body) {
    res.setHeader('Content-Type', 'text/html; charset=utf-8');
    res.end(body);
  }