scratch.el

;; Scratch
;; This program helps keep a record of ideas.
;; Last edit: 2012-07-05
;; Every time (scratch) is called a new buffer is opened. Title
;; is today's date appended before a user inputed title.

;Needed features
;* An interactive shell that shows me a list of entries
; from a certain time period.

;The journal folder. This should be set in the .emacs file.
;(setq scratch-folder "~/Documents/Ideas")

;Format for entry filename
(setq scratch-entry-format "%Y-%m-%d")


;Internal Constants
(setq sep "/")

;; Functions
(defun todays-filename ()
  "The last modification time of a file.
Returned in the format YYYYMMDDHHMMSS."
  (format-time-string scratch-entry-format))

(defmacro inc (x)
  "increments x by 1."
  `(setq ,x (1+ ,x)))


(defmacro remove-starting-char (string char)
  "removes a char from the start of a string."
  `(if (string= (substring ,string 0 1) ,char)
       (setq ,string (substring ,string 1 (length ,string)))))

(defmacro remove-ending-char (string char)
  "removes a char from the end of a string."
  `(let ((l (length ,string)))
     (if (string= (substring ,string (1- l) l)
		  ,char)
	 (setq ,string (substring ,string 0 (1- l))))))


(defun concat-paths (&rest paths)
  "Given a set of paths concats them.
Makes sure that sep are alright."
  (let ((n (length paths))
	(i 0)
	(concated-path "")
	(path)
	(subpath))
    (while (< i n)
      (setq subpath (nth i paths))
      (if (not (= i 0))
	  (remove-starting-char subpath sep))
      (if (> (length subpath) 0)
	  (progn
	    (remove-ending-char subpath sep)
	    (setq concated-path (concat concated-path
					subpath
					sep))))
      (inc i))
    (remove-ending-char concated-path sep)))
;The following two functions taken from
; https://sites.google.com/site/steveyegge2/my-dot-emacs-file
(defun rename-file-and-buffer (new-name)
 "Renames both current buffer and file it's visiting to NEW-NAME."
 (interactive "sNew name: ")
 (let ((name (buffer-name))
       (filename (buffer-file-name)))
   (if (not filename)
       (message "Buffer '%s' is not visiting a file!" name)
     (if (get-buffer new-name)
	 (message "A buffer named '%s' already exists!" new-name)
       (progn
	 (rename-file name new-name 1)
	 (rename-buffer new-name)
	 (set-visited-file-name new-name)
	 (set-buffer-modified-p nil))))))

(defun move-buffer-file (dir)
 "Moves both current buffer and file it's visiting to DIR." (interactive "DNew directory: ")
 (let* ((name (buffer-name))
	(filename (buffer-file-name))
	(dir
	 (if (string-match dir "\\(?:/\\|\\\\)$")
	     (substring dir 0 -1) dir))
	(newname (concat dir "/" name)))
   (if (not filename)
       (message "Buffer '%s' is not visiting a file!" name)
     (progn
       (copy-file filename newname 1) 	
       (delete-file filename) 	
       (set-visited-file-name newname) 
       (set-buffer-modified-p nil) 	
       t)))) 

(defun scratch ()
  "Create's or appends to today's journal entry."
  (interactive)
  (let ((file (concat-paths scratch-folder (todays-filename))))
    (find-file file)
    (auto-fill-mode -5)
    (restore-buffer-modified-p t)
    (save-buffer)
    (goto-char (point-max))
    (title-scratch)
    (message "Scratch an idea...")))

(defun title-scratch ()
  (interactive)
  (let ((date (substring (buffer-name (current-buffer)) 0 10))
	(title))
    (setq title (read-from-minibuffer "Title for idea: "))
    (if (not (string= title ""))
	(rename-file-and-buffer (concat date " " title)))))