rodo/rodo.rkt

#! /usr/bin/env racket 
#lang racket/base

(require racket/vector)

(define program-name "rodo")
(define program-directory ".rodo/")
(define program-path "~/")

(define (d-hash-ref hash-list key)
  (display (hash-ref messages key)))

(define (d-vector-ref args key)
  (display (vector-ref args key)))

(define messages 
  (hash 
    'incorrect-usage (string-append 
                       "> For usage type " 
                       "`" program-name " -h`" 
                       " or " 
                       "`" program-name " --help`\n")

    'creating (string-append 
                "> Creating a " 
                program-directory 
                " folder in " 
                program-path " ...\n")

    'creation-error (string-append 
                      "> Error: Could not create " 
                      program-directory 
                      " in " 
                      program-path ".\n" 
                      "> This may be due to directory permissions\n")

    'already-exists (string-append 
                      "> " 
                      program-directory 
                      " folder already exists in " 
                      program-path "\n")

    'successfully-created (string-append 
                            "> " 
                            program-path program-directory 
                            " has been successfully created\n") 

    'not-found (string-append 
                 "> " 
                 program-directory 
                 " has not been setup in " 
                 program-path "\n"
                 "> Would you like to set it up now? [y/n]\n")

    'choose-y/n "> Error: Please choose y or n\n"

    'item-added-prefix "> Added " 
    'item-added-suffix " to list\n" 

    'item-removed-prefix "> Removed "
    'item-removed-suffix " from list\n"

    'terminating (string-append "> Exiting " program-name " ...\n")))

;; some possible user-input related "mistakes" that 
;; will be accepted for input
(define y/n 
  (hash
    'yes '("yes" "Yes" "y" "Y")
    'no '("no" "No" "n" "N")))

(define (open/create-file list-name)
  (let ([path (expand-user-path (string-append 
                                  program-path 
                                  program-directory 
                                  list-name))])
    (let ([opened-file (open-output-file path
                                         #:mode 'text
                                         #:exists 'can-update)])
      (close-output-port opened-file))))

(define (create-folder)
  (make-directory (expand-user-path (string-append 
                                      program-path 
                                      program-directory))))

(define (check-for-folder)
  (directory-exists? (expand-user-path (string-append 
                                         program-path 
                                         program-directory))))

;; prompt user for file initial file creation 
(define (prompt-user chosen-message)
  (d-hash-ref messages chosen-message)
  (display "> ")
  (let ([user-input (read-line)])
    (cond
      [(member user-input (hash-ref y/n 'yes))  
       (d-hash-ref messages 'creating)
       (create-folder)
       (if (check-for-folder)
         (d-hash-ref messages 'successfully-created)
         (d-hash-ref messages 'creation-error))]

      [(member user-input (hash-ref y/n 'no))  
       (d-hash-ref messages 'terminating)]

      [else 
        (prompt-user 'choose-y/n)])))

(define (check-args args)
  (let ([args-length (vector-length args)])
    (cond
      [(and (equal? args-length 2) (equal? (vector-member "add" args) 0))
       (d-hash-ref messages 'item-added-prefix) 
       (d-vector-ref args 1) 
       (d-hash-ref messages 'item-added-suffix)]

      [(and (equal? args-length 2) (equal? (vector-member "remove" args) 0))
       (d-hash-ref messages 'item-removed-prefix) 
       (d-vector-ref args 1) 
       (d-hash-ref messages 'item-removed-suffix)]

      [(and (equal? args-length 1) (equal? (vector-member "init" args) 0))
       (todo-list-exist?)]

      [else (d-hash-ref messages 'incorrect-usage)])))

;; does the file exist that holds the list(s?)
(define (todo-list-exist?)
  (if (check-for-folder)
    (d-hash-ref messages 'already-exists)
    (prompt-user 'not-found)))

(define (main)
  (check-args (current-command-line-arguments)))

(main)