Robot Traversal

returnsToOrigin.js

const returnsToOrigin = (commandString) => {

  let heading = 'n';
  let distanceX = 0;
  let distanceY = 0;

  const adjustDistance = (command) => {
    if (command ==='g') {
      if      (heading === 'n') { distanceY++ } 
      else if (heading ==='e') { distanceX++ }
      else if (heading ==='s') { distanceY-- }
      else if (heading ==='w') { distanceX-- }
      }
    else if (command ==='r') {
      if      (heading === 'n') { heading = 'e' } 
      else if (heading ==='e') { heading = 's' }
      else if (heading ==='s') { heading = 'w' }
      else if (heading ==='w') { heading = 'n' }
    }
    else if (command ==='l') {
      if      (heading === 'n') { heading = 'w' } 
      else if (heading ==='e') { heading = 'n' }
      else if (heading ==='s') { heading = 'e' }
      else if (heading ==='w') { heading = 's' }
    }
  }

  const batchCommands = (commandString) => {
    const commandArray = commandString.toLowerCase().split('');
    commandArray.forEach( command => {
      adjustDistance(command)
    });
  }

  batchCommands(commandString)

  return distanceX === 0 && distanceY === 0;

}