/**
   * @fileoverview HTML reporter
   * @author Julian Laval
   */
  "use strict";
  
  const lodash = require("lodash");
  const fs = require("fs");
  const path = require("path");
  
  //------------------------------------------------------------------------------
  // Helpers
  //------------------------------------------------------------------------------
  
  const pageTemplate = lodash.template(fs.readFileSync(path.join(__dirname, "html-template-page.html"), "utf-8"));
  const messageTemplate = lodash.template(fs.readFileSync(path.join(__dirname, "html-template-message.html"), "utf-8"));
  const resultTemplate = lodash.template(fs.readFileSync(path.join(__dirname, "html-template-result.html"), "utf-8"));
  
  /**
   * Given a word and a count, append an s if count is not one.
   * @param {string} word A word in its singular form.
   * @param {int} count A number controlling whether word should be pluralized.
   * @returns {string} The original word with an s on the end if count is not one.
   */
  function pluralize(word, count) {
      return (count === 1 ? word : `${word}s`);
  }
  
  /**
   * Renders text along the template of x problems (x errors, x warnings)
   * @param {string} totalErrors Total errors
   * @param {string} totalWarnings Total warnings
   * @returns {string} The formatted string, pluralized where necessary
   */
  function renderSummary(totalErrors, totalWarnings) {
      const totalProblems = totalErrors + totalWarnings;
      let renderedText = `${totalProblems} ${pluralize("problem", totalProblems)}`;
  
      if (totalProblems !== 0) {
          renderedText += ` (${totalErrors} ${pluralize("error", totalErrors)}, ${totalWarnings} ${pluralize("warning", totalWarnings)})`;
      }
      return renderedText;
  }
  
  /**
   * Get the color based on whether there are errors/warnings...
   * @param {string} totalErrors Total errors
   * @param {string} totalWarnings Total warnings
   * @returns {int} The color code (0 = green, 1 = yellow, 2 = red)
   */
  function renderColor(totalErrors, totalWarnings) {
      if (totalErrors !== 0) {
          return 2;
      } else if (totalWarnings !== 0) {
          return 1;
      }
      return 0;
  }
  
  /**
   * Get HTML (table rows) describing the messages.
   * @param {Array} messages Messages.
   * @param {int} parentIndex Index of the parent HTML row.
   * @returns {string} HTML (table rows) describing the messages.
   */
  function renderMessages(messages, parentIndex) {
  
      /**
       * Get HTML (table row) describing a message.
       * @param {Object} message Message.
       * @returns {string} HTML (table row) describing a message.
       */
      return lodash.map(messages, message => {
          const lineNumber = message.line || 0;
          const columnNumber = message.column || 0;
  
          return messageTemplate({
              parentIndex,
              lineNumber,
              columnNumber,
              severityNumber: message.severity,
              severityName: message.severity === 1 ? "Warning" : "Error",
              message: message.message,
              ruleId: message.ruleId
          });
      }).join("
  ");
  }
  
  /**
   * @param {Array} results Test results.
   * @returns {string} HTML string describing the results.
   */
  function renderResults(results) {
      return lodash.map(results, (result, index) => resultTemplate({
          index,
          color: renderColor(result.errorCount, result.warningCount),
          filePath: result.filePath,
          summary: renderSummary(result.errorCount, result.warningCount)
  
      }) + renderMessages(result.messages, index)).join("
  ");
  }
  
  //------------------------------------------------------------------------------
  // Public Interface
  //------------------------------------------------------------------------------
  
  module.exports = function(results) {
      let totalErrors,
          totalWarnings;
  
      totalErrors = 0;
      totalWarnings = 0;
  
      // Iterate over results to get totals
      results.forEach(result => {
          totalErrors += result.errorCount;
          totalWarnings += result.warningCount;
      });
  
      return pageTemplate({
          date: new Date(),
          reportColor: renderColor(totalErrors, totalWarnings),
          reportSummary: renderSummary(totalErrors, totalWarnings),
          results: renderResults(results)
      });
  };