Refactoring to improve code maintainability:

 * Fixing the error handling bug introduced by the config feature

 * Refactor options validation and parsing into a new Options class

 * Move the HTML generation and tool options module to bin

 * Refactor paths for options and generate html modules

 * Improve linting and indentation

bin/index.js

@@ -1,14 +1,13 @@
 #!/usr/bin/env node
 
 const package = require("../package");
-const generateHtml = require("../generateHtml");
-const fs = require("fs");
+const generateHtml = require("./modules/generateHtml");
 const figlet = require("figlet");
-const path = require("path");
-const { exit } = require("process");
+const { Options } = require("./modules/configOptions");
 
 const outputDir = './dist';
 const defaultLang = 'en-CA';
+let options;
 
 const decoratedHeader = figlet.textSync(package.name, {horizontalLayout: 'full'});
 console.log(decoratedHeader);
@@ -52,61 +51,20 @@ var argv = require('yargs/yargs')(process.argv.slice(2))
     }
   })
   .check((argv) => {
+    options = new Options(argv.i, argv.o, argv.s, argv.l);
 
-    //Input
-    if(argv.i){
-
-      if(!fs.existsSync(argv.i)){
-        throw new Error("Input path must be a file or directory");
-      }
-    }
-
-    //Output
-    else if(argv.o != outputDir){
-      if(fs.existsSync(argv.o)){
-        if(!fs.lstatSync(argv.o).isDirectory()){
-          throw new Error("Output path points to a file. Output directory must be valid")
-        }
-      }
-      else throw new Error("Output directory must be valid");
+    if(argv.c){
+      //Parse and use options from the config file
+      options.parseConfig(argv.c);
     }
 
-    //Config
-    else if(argv.c){
-
-      if(isJSON(process.argv[3])){
-
-        if(!fs.existsSync(argv.c)){
-          throw new Error("JSON file path does not exist");
-        }
-        var data = JSON.parse(fs.readFileSync(argv.c));
-
-        if(data.input)      argv.i = data.input
-        if(data.output)     argv.o = data.output
-        if(data.stylesheet) argv.s = data.stylesheet
-        if(data.lang)       argv.l = data.lang
-
-      }else{
-        throw new Error("The passed file should be of JSON format")
-      }
-    }
-    else {
-      throw new Error("A config file(.JSON) or an input file is required");
-    }
-
-    return true;
+    //Validate the options
+    return options.validateInput() && options.validateOutput();
   })
   .argv;
 
 try {
-    generateHtml(argv.i, argv.o, argv.s, argv.l);
-  } catch (err) {
-    console.error(err)
-  }
-
-  function isJSON(stats){
-    if(path.extname(stats) == ".json") 
-      return true
-    else 
-      return false
-  }
+  generateHtml(options.input, options.output, options.stylesheet, options.lang);
+} catch (err) {
+  console.error(err)
+}

bin/modules/configOptions.js

@@ -0,0 +1,76 @@
+const fs = require("fs");
+const path = require("path");
+const chalk = require("chalk");
+
+class Options {
+  constructor(input, output, stylesheet, lang){
+    this.input = input;
+    this.output = output;
+    this.stylesheet = stylesheet;
+    this.lang = lang;
+  }
+  static get DEFAULT_OUTPUT(){ return './dist'; }
+  static get DEFAULT_LANG(){ return 'en-CA'; }
+
+  //Returns true if the input path is validated, otherwise throws an error
+  validateInput(){
+    if(!fs.existsSync(this.input)){
+      throw new Error(`${this.input} does not exist. Input path must be a file or directory`);
+    }
+    return true;
+  }
+
+  //Returns true if the output path is validated, otherwise throws an error
+  validateOutput(){
+    if(this.output != Options.DEFAULT_OUTPUT){
+      if(fs.existsSync((this.output))){
+        if(!fs.lstatSync((this.output)).isDirectory()){
+          throw new Error("Output path points to a file. Output directory must be valid")
+        }
+      }
+      else throw new Error(`${this.output} does not exist. Output directory must be valid`);
+    }
+    return true;
+  }
+
+  /**
+   * Parses options using a file path
+   * @param {string} filePath 
+   * @return {Boolean} true if the options were parsed
+   */
+  parseConfig(filePath){
+    if(fs.existsSync(filePath)){
+      if(path.extname(filePath).toLocaleLowerCase() == '.json'){
+        let fileContents = fs.readFileSync(filePath);
+        let configData;
+
+        try{
+          configData = JSON.parse(fileContents);
+        }
+        catch(err){
+          console.log('Error while parsing JSON: ', err);
+          process.exit(-1);
+        }
+
+        this.input = configData.input;
+        this.output = configData.output ? configData.output : Options.DEFAULT_OUTPUT;
+        this.lang = configData.lang ? configData.lang : Options.DEFAULT_LANG;
+        this.stylesheet = configData.s;
+
+      }
+      else {
+        console.log("Config file must be JSON!", path.extname(filePath));
+        process.exit(-1);
+      }
+    }
+    else {
+      console.log(`${filePath} not found! A JSON config file must be supplied`);
+      process.exit(-1);
+    }
+
+    console.log(chalk.green(`Options successfully retrieved from ${filePath}`));
+    return true;
+  }
+}
+
+module.exports.Options = Options;

generateHtml.js → bin/modules/generateHtml.js

@@ -60,8 +60,6 @@ const convertMdFileToHtml = (filePath, stylesheet, lang) => {
       .replace(/\~\~(.*)\~\~/gim, '<del>$1</del>')
       .replace(/\[(.*?)\]\((.*?)\)/gim, "<a href='$2'>$1</a>")
       .replace(/^<http(.*)$/gim, "<a href='http$1'>http$1</a>");
-
-
 
     const html = encloseInHtml(title[0].slice(2), body.trim(), stylesheet, lang);
     const outputFilePath = path.join(outputDir, path.basename(filePath, '.md') + '.html')
@@ -73,12 +71,12 @@ const convertMdFileToHtml = (filePath, stylesheet, lang) => {
  * @param {string} path
  */
 const parseFile = (path) => {
-    try {
-        const data = fs.readFileSync(path, 'utf8')
-        return data;
-      } catch (err) {
-        console.error(err)
-      }
+  try {
+    const data = fs.readFileSync(path, 'utf8')
+    return data;
+  } catch (err) {
+    console.error(err)
+  }
 }
 
 /**
@@ -102,7 +100,7 @@ const parseFile = (path) => {
       <h1>${title}</h1>
       ${body}
     </body>
-    </html>`
+    </html>`;
 }
 
 /**
@@ -140,8 +138,8 @@ const checkDirForTxt = (dirPath) => {
  * @param {string} stylesheet - optional language attribute for html element
  */
 const main =  (input, output, stylesheet, lang) => {
-
     outputDir = output;
+
     //Create empty directory for output
     if (!fs.existsSync(outputDir)){
         fs.mkdirSync(outputDir, {recursive: true});