diff --git a/src/nicethings.rkt b/src/nicethings.rkt index 60ed1dd..fce07bd 100644 --- a/src/nicethings.rkt +++ b/src/nicethings.rkt @@ -6,165 +6,179 @@ racket/string) ;; ------------------------------------------------ -;; values +;; Constants ;; ------------------------------------------------ -(define help-command "help") +(define help-command-1 "help") +(define help-command-2 "--help") +(define help-command-3 "-h") +(define init-command "init") (define ls-command "ls") (define rm-command "rm") (define add-command "add") (define program-name "nicethings") -(define program-name-dotted (string-append "." program-name)) -;; /home/username/ -(define home-directory-path (find-system-path 'home-dir)) -(define program-path (build-path home-directory-path program-name-dotted)) -(define correct-permissions 420) ;; -rw-r--r-- permissions -(define message-prefix "> ") +(define program-file (string-append "." program-name)) +(define program-path (build-path (find-system-path 'home-dir) program-file)) +(define program-permissions 420) ;; 644/-rw-r--r-- permissions +(define newline "\n") +(define double-newline "\n\n") ;; ------------------------------------------------ -;; messages +;; Messages ;; ------------------------------------------------ (define messages (hash - 'error-add (list (format "Error: No arguments were found after the '~a' command." add-command) - (format "Suggestion: Try using a quoted argument after the '~a' command." ls-command) - (format "Example: ~a add \"Go for a walk\"" program-name)) + 'error-too-many-arguments + (format (string-append "Error: Too many arguments." newline + "Try running '~a ~a' for more information.") + program-name + help-command-1) - 'item-not-found (list "Error: Item not found." - (format "Suggestion: Try using the '~a' command to see which number " ls-command) - " correlates to which message in your list." - (format "Example: ~a ~a" program-name ls-command)) + 'error-incorrect-usage + (format (string-append "Error: Incorrect usage." newline + "Try running '~a ~a' for more information.") + program-name + help-command-1) - 'error-rm (list (format "Error: No arguments were found after the '~a' command." rm-command) - (format "Suggestion: Try using a number after the '~a' command." rm-command) - (format "Example: ~a ~a 2" program-name rm-command) - "" - (format "Note: You may need to run the '~a' command to see which " ls-command) - " number correlates to which item in your list." - (format "Example: ~a ~a" program-name ls-command)) + 'error-file-already-exists + (format "Error: The file '~a' already exists." program-path) - 'error-usage (list "Error: Incorrect usage." - (format "Suggestions: Try running the '~a' command." help-command) - (format "Example: ~a ~a" program-name help-command)) + 'error-fake-file-exists + (format (string-append "Error: The directory '~a' exists." newline + "Try moving, renaming, or deleting this directory.") + program-path) - 'error-ls (list (format "Error: Found arguments after the '~a' command." ls-command) - (format "Suggestions: Try using '~a' without any arguments." ls-command) - (format "Example: ~a ~a" program-name ls-command)) + 'error-file-doesnt-exist + (format (string-append "Error: '~a' doesn't exist." newline + "Try running '~a ~a'.") + program-path + program-name + init-command) - 'error-fake-file (list (format "Error: A '~a' directory was found in your home directory." program-name-dotted) - (format "Suggestion 1: Move the '~a' directory out of your " program-name-dotted) - (format " home directory before using ~a." program-name) - (format "Suggestion 2: Rename the '~a' directory before using ~a." program-name-dotted program-name)) + 'error-item-not-found + "Error: Item not found." - 'error-permissions-prompt (list (format "Error: '~a''s permissions are incorrect." program-path) - "Would you like to fix them? [y/n]") - 'cancel-creation (list (format "Cancelled the creation of ~a." program-path)) + 'warning-permissions + (format (string-append "Warning: The permissions on your '~a' file are incorrect." newline + "Other users on this host may be able to read your file." newline + "Try running 'chmod 600 ~a' to fix this." newline) + program-path + program-path) - 'permissions-fixed (list (format "'~a''s permissions were successfully fixed." program-path)) + 'init-cancelled + (format "Cancelled the creation of '~a'." program-path) - 'file-created (list (format "'~a' was successfully created." program-path)) + 'init-prompt + (format (string-append "~a will create '~a'." newline + "Is this okay? [y/n]") + program-name + program-path) - 'not-found-prompt (list (format "'~a' wasn't found." program-path) - "Would you like to create it? [y/n]") + 'file-created + (format "Successfully created ~a." program-path) - 'error-option (list "Error: '~a' is not an option.") + 'empty-list + "There is nothing in your list.")) - 'empty-list (list "There is nothing in your list.") +(define formatees + (hash + 'error-not-an-option + (string-append "Error: '~a' is not an option." newline + "Please choose 'y' or 'n'.") - 'added (list "Added '~a' to your list.") + 'error-not-a-number + (string-append "Error: '~a' is not a number.") - 'removed (list "Removed '~a' from your list."))) + 'added + "Added '~a' to your list." + + 'removed + "Removed '~a' from your list.")) ;; ------------------------------------------------ ;; helpers ;; ------------------------------------------------ (define (messages-ref key) - (map (lambda (element) (string-append message-prefix element)) - (hash-ref messages key))) + (hash-ref messages key)) -(define-syntax-rule (displayln-message-format key string ...) - (let ([string-to-format (string-join (messages-ref key) "\n")]) - (displayln (format string-to-format string ...)))) +(define (formatees-ref key) + (hash-ref formatees key)) -(define (displayln-message-list key) - (let ([listof-strings (messages-ref key)]) - (for ([string listof-strings]) - (displayln string)))) +(define (displayln-messages-ref key) + (let ([message (messages-ref key)]) + (displayln message))) -(define (displayln-for . strings) - (for ([string strings]) - (displayln string))) +(define (displayln-formatees-ref key string) + (let* ([formatee (formatees-ref key)] + [formatee-formatted (format formatee string)]) + (displayln formatee-formatted))) -(define (file-has-correct-permissions? file) - (equal? correct-permissions (file-or-directory-permissions file 'bits))) +(define (create-file string) + (close-output-port + (open-output-file string))) + +(define (has-program-permissions? string) + (equal? program-permissions (file-or-directory-permissions string 'bits))) ;; ------------------------------------------------ -;; repair +;; Check conditions ;; ------------------------------------------------ -(define (repair/not-an-option user-input) - (displayln-message-format 'error-option user-input) - (exit)) - -(define (repair/cancel) - (displayln-message-list 'cancel-creation) - (exit)) - -(define (repair/fake-file) - (displayln-message-list 'error-fake-file) - (exit)) - -(define (repair/create-exit-mode key) - (match key - [(or 'ls 'rm) (exit)] - ['add 'do-nothing])) - -(define (repair/fix-permissions key) - (file-or-directory-permissions program-path correct-permissions) - (displayln-message-list 'permissions-fixed) - (repair/create-exit-mode key)) - -(define (repair/wrong-permissions key) - (displayln-message-list 'error-permissions-prompt) - (display message-prefix) - (let ([user-input (read-line)]) - (case (string->symbol user-input) - ['y (repair/fix-permissions key)] - ['n (repair/cancel)] - [else (repair/not-an-option user-input)]))) - -(define (repair/create-file key) - (close-output-port (open-output-file program-path)) - (file-or-directory-permissions program-path correct-permissions) - (displayln-message-list 'file-created) - (repair/create-exit-mode key)) - -(define (repair/not-found key) - (displayln-message-list 'not-found-prompt) - (display message-prefix) - (let ([user-input (read-line)]) - (case (string->symbol user-input) - ['y (repair/create-file key)] - ['n (repair/cancel)] - [else (repair/not-an-option user-input)]))) - -(define (repair key) +(define (check-conditions) (cond [(directory-exists? program-path) - (repair/fake-file)] + (begin (displayln-messages-ref 'error-fake-file-exists) + (exit))] [(not (file-exists? program-path)) - (repair/not-found key)] + (begin (displayln-messages-ref 'error-file-doesnt-exist) + (exit))] - [(not (file-has-correct-permissions? program-path)) - (repair/wrong-permissions key)] + [(not (has-program-permissions? program-path)) + (displayln-messages-ref 'warning-permissions)] [else 'do-nothing])) + +;; ------------------------------------------------ +;; init +;; ------------------------------------------------ +(define (init/create-file) + (create-file program-path) + (file-or-directory-permissions program-path + program-permissions) + (displayln-messages-ref 'file-created)) + +(define (init/cancel) + (displayln-messages-ref 'init-cancelled) + (exit)) + +(define (init/prompt) + (displayln-messages-ref 'init-prompt) + (display "> ") + (let* ([input (read-line)] + [input-symbol (string->symbol input)]) + (case input-symbol + ['y (init/create-file)] + ['n (init/cancel)] + [else (displayln-formatees-ref 'error-not-an-option input)]))) + +(define (init) + (cond + [(file-exists? program-path) + (displayln-messages-ref 'error-file-already-exists)] + + [(directory-exists? program-path) + (displayln-messages-ref 'error-fake-file-exists)] + + [else (init/prompt)])) + ;; ------------------------------------------------ ;; ls ;; ------------------------------------------------ (define (ls/display-list listof-items) - ;; add1 starts the listof-numbers at 1 instead of 0 + ;; The add1 in the first binding starts the + ;; listof-numbers at 1 instead of 0 to make the + ;; list numbering more human-friendly (let* ([listof-numbers (map add1 (range (length listof-items)))] [listof-number-strings (map number->string listof-numbers)] [combine-lists (lambda (a b) (string-append a ". " b))] @@ -172,87 +186,87 @@ listof-number-strings listof-items)]) (for ([item listof-numbered-items]) - (displayln item)))) + (displayln item)))) (define (ls) - (repair 'ls) + (check-conditions) (let ([listof-items (file->lines program-path)]) (if (null? listof-items) - (displayln-message-list 'empty-list) + (displayln-messages-ref 'empty-list) (ls/display-list listof-items)))) ;; ------------------------------------------------ ;; rm ;; ------------------------------------------------ -(define (rm/remove-item listof-items item-number-sub1) - (let* ([item-to-remove (list-ref listof-items item-number-sub1)] +(define (rm/remove-item listof-items item-number) + (let* ([item-to-remove (list-ref listof-items item-number)] [list-without-item (remove item-to-remove listof-items)]) (display-lines-to-file list-without-item program-path #:exists 'truncate) - (displayln-message-format 'removed item-to-remove))) + (displayln-formatees-ref 'removed item-to-remove))) -(define (rm string) - (repair 'rm) +(define (rm/process-string string) (let* ([listof-items (file->lines program-path)] - ;; subtract 1 because the index starts at - ;; 0 under the hood, but the numbers presented from 'ls' - ;; start at 1. - [item-number (string->number string)] - [item-number-sub1 (sub1 item-number)] - [list-length (length listof-items)]) + [item-number (string->number string)] + ;; Subtract 1 from the user's original number, + ;; because we want to convert the number from + ;; human numbers (1 2 3) to index numbers + ;; (0 1 2) + [item-number-sub1 (sub1 item-number)] + [list-length (length listof-items)]) (if (and (not (null? listof-items)) (number? item-number) (positive? item-number) - ;; 1 less than length, because we want to - ;; remove the index number, which is one less - ;; than the item the user chose + ;; Don't allow numbers that are equal to + ;; or greater than list-length, because + ;; the list index starts at 0 + ;; ;; Example: - ;; We have a list length of 3: - ;; '(1 2 3) - ;; `list-ref` in rm/remove-item above - ;; uses an index that starts at 0, so - ;; the index of the numbers above are: - ;; '(0 1 2) - ;; The 2 is the last index number in a - ;; list of length 3, which is what we - ;; want, because if you try to remove - ;; an index larger than 2, such as the - ;; list length 3, then that would be - ;; an error + ;; Length of (1 2 3) = 3 + ;; + ;; To reference the highest number, we + ;; use (list-ref (1 2 3) 2) (< item-number-sub1 list-length)) (rm/remove-item listof-items item-number-sub1) - (displayln-message-list 'item-not-found)))) + (displayln-messages-ref 'error-item-not-found)))) + +(define (rm string) + (check-conditions) + (if (string->number string) + (rm/process-string string) + (displayln-formatees-ref 'error-not-a-number string))) ;; ------------------------------------------------ ;; add ;; ------------------------------------------------ -;; The string-cleaned and -remade is incase there -;; are multiple newline characters. This ensures -;; there is only one newline character. (define (add string) - (repair 'add) + (check-conditions) + ;; The removing and adding of the '\n' is to + ;; ensure only one '\n' exists at the end of the + ;; item to be added. (let* ([string-no-newline (string-replace string "\n" "")] [string-newline (string-append string-no-newline "\n")]) (display-to-file string-newline program-path #:exists 'append) - (displayln-message-format 'added string-no-newline))) + (displayln-formatees-ref 'added string-no-newline))) ;; ------------------------------------------------ ;; random message ;; ------------------------------------------------ -(define (random-message/append-nicethings-file home-directory) - (build-path home-directory program-name-dotted)) +(define (random-message/append-program-file home-directory) + (build-path home-directory program-file)) (define (random-message) (let* ([root (find-system-path 'sys-dir)] ;; / [root-home (build-path root "home")] ;; /home - [listof-homes (directory-list root-home #:build? #t)] - [paths-to-nicethings (map random-message/append-nicethings-file listof-homes)] - [directories-with-nicethings (filter file-exists? paths-to-nicethings)] - [directories-with-420 (filter file-has-correct-permissions? directories-with-nicethings)] - [listof-nicethings (apply append (map file->lines directories-with-420))] + ;; `#:build? #t` Builds full paths for all items listed in /home/ + [listof-home-directories (directory-list root-home #:build? #t)] + [listof-nicethings-paths (map random-message/append-program-file listof-home-directories)] + [directories-with-nicethings (filter file-exists? listof-nicethings-paths)] + [directories-with-644 (filter has-program-permissions? directories-with-nicethings)] + [listof-nicethings (apply append (map file->lines directories-with-644))] [list-length (length listof-nicethings)]) (when (not (zero? list-length)) (let* ([random-number (random list-length)] @@ -263,40 +277,63 @@ ;; help ;; ------------------------------------------------ (define (help) - (displayln-for - "Usage:" - (format " ~a [] []" program-name) - "" - "Commands:" - (format " ~a - Adds an item to your list." add-command) - (format " ~a - Prints a numbered list of your items." ls-command) - (format " ~a - Removes an item from your list." rm-command) - "" - "Examples:" - (format " ~a ~a \"You are beautiful\"" program-name add-command) - (format " ~a ~a" program-name ls-command) - (format " ~a ~a 2" program-name rm-command))) + (displayln + (string-append + "Usage:" newline + (format " ~a [] []" program-name) + double-newline + + "Commands:" newline + " No command - Displays a random nicething from a random user." newline + (format " ~a - Creates a file in ~a, which allows you to contribute to the town-wide list of nicethings." + init-command + program-path) newline + (format " ~a - Adds a nicething to your list." add-command) newline + (format " ~a - Prints a numbered list of the nicethings you've added." ls-command) newline + (format " ~a - Removes a nicething from your list." rm-command) + double-newline + + "Examples:" newline + (format " ~a" program-name) newline + (format " ~a ~a" program-name init-command) newline + (format " ~a ~a \"You are wonderful\"" program-name add-command) newline + (format " ~a ~a" program-name ls-command) newline + (format " ~a ~a 2" program-name rm-command)))) (define (process-args vectorof-args) (define (args-ref number) (vector-ref vectorof-args number)) (match vectorof-args - ;; Proper usage - [(or '#("-h") - '#("--help") - '#("help")) (help)] - [(vector "add" _) (add (args-ref 1))] - [(vector "rm" _) (rm (args-ref 1))] - [(vector "ls") (ls)] - [(vector) (random-message)] - ;; Improper usage - ;; This is checked so we can give the user hints on how to - ;; use the software if they have part of the command - ;; correct - [(vector "ls" _) (displayln-message-list 'error-ls)] - [(vector "add") (displayln-message-list 'error-add)] - [(vector "rm") (displayln-message-list 'error-rm)] - [(vector _ ...) (displayln-message-list 'error-usage)])) + [(vector a) + (cond + [(ormap (lambda (x) (equal? a x)) + (list help-command-1 + help-command-2 + help-command-3)) + (help)] + + [(equal? a ls-command) + (ls)] + + [(equal? a init-command) + (init)] + + [else (displayln-messages-ref 'error-incorrect-usage)])] + + [(vector a _) + (cond + [(equal? a add-command) + (add (args-ref 1))] + + [(equal? a rm-command) + (rm (args-ref 1))] + + [else (displayln-messages-ref 'error-incorrect-usage)])] + + [(vector _ _ _ ...) + (displayln-messages-ref 'error-too-many-arguments)] + + [_ (random-message)])) (define (main vectorof-args) (process-args vectorof-args))