sirrobert-shell-cmd-help/src/Help.js

A Help command for the nodejs shell.

var fs    = require('fs');
var util  = require("src/util.js");
var path  = require('path');
var color = require("src/color.js");

// A Help file is loaded with a path.  The path looks like this, say:
//
//    shell.commands.quit
//
// which expands to the file
//  
//    ./help/shell/commands/quit.help
//
// This is a plain text file that is displayed without formatting.
function Help (path) {
  this.text = null;
  this.path = path;
  this.cache = false;
};

Help.prototype.display = function (options) {
  // if we've already loaded this help file, great just show it.  If we
  // haven't, we need to load it.
  if (this.text) {
    process.stdout.write(
      color.set.blue("\n" + this.text + "\n")
    );

    if (options && options.after) {
      options.after();
    }

    if (!this.cache) {
      this.text = null;
    }
    return;
  }

  var disk_path = process.program_dir + "/help/" + this.path.replace(/\./g,'/') + ".help";
  var help = this;

  fs.readFile(disk_path, function (err, data) {
    if (err) {
      return util.log(
        "error",
        "Help.display()",
        "File does not exist.",
        [help.path, disk_path]);
    }

    // If we got a file, save it to the help.text variable and then
    // re-call this method.
    help.text = data;
    help.display(options);
  });
}

module.exports = Help;