-(defvar darkroom-margins 0.15
- "Margins to use in darkroom-mode.
-
-It's value can be:
+;;; darkroom.el --- Remove visual distractions and focus on writing -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2014 João Távora
+
+;; Author: João Távora <joaotavora@gmail.com>
+;; Keywords: convenience, emulations
+;; Version: 0.1
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; The main entrypoints to this extension are two minor modes
+;;
+;; M-x darkroom-mode
+;; M-x darkroom-tentative-mode
+;;
+;; The first makes current buffer to enter `darkroom-mode'
+;; immediately: keeping the window configuration untouched, text is
+;; enlarged, centered on the window with margins, and the modeline is
+;; elided.
+;;
+;; The second, `darkroom-tentative-mode', makes the current buffer
+;; turn on `darkroom-mode' whenever all other windows are deleted,
+;; i.e. the buffer is solo on the current Emacs frame. Whenever the
+;; window is split to display some other buffer, the original buffer's
+;; configuration is reset.
+;;
+;; Personally, I always use `darkroom-tentative-mode'.
+;;
+;; See also the customization options `darkroom-margins' and
+;; `darkroom-fringes-outside-margins', which affect both modes.
+
+;;; Code:
+
+(defgroup darkroom nil
+ "Remove visual distractions and focus on writing"
+ :prefix "darkroom-"
+ :group 'emulations)
+
+(defcustom darkroom-margins 0.15
+ "Margins to use in `darkroom-mode'.
+
+Its value can be:
- a floating point value betweeen 0 and 1, specifies percentage of
window width in columns to use as a margin.
- a cons cell (LEFT RIGHT) specifying the left and right margins
in columns.
-- a function that returns a cons cell interpreted like the
- previous option.
-
-Value is effective when `darkroom-minor-mode' is toggled, when
-changing window or by calling `darkroom-set-margins'")
-
-(defvar darkroom-turns-on-visual-line-mode t
- "If non-nil pair `visual-line-mode' with
- `darkroom-minor-mode'")
-(defvar darkroom-fringes-outside-margins t
- "If non-nil use fringes outside margins for `darkroom-minor-mode'")
-
-(defun darkroom-margins ()
- (cond ((functionp darkroom-margins)
- (funcall darkroom-margins))
- ((consp darkroom-margins)
- darkroom-margins)
- ((and (floatp darkroom-margins)
- (< darkroom-margins 1))
- (let ((delta (darkroom-float-to-columns darkroom-margins)))
- (cons delta delta)))))
+- a function of no arguments that returns a cons cell interpreted
+ like the previous option.
+
+Value is effective when `darkroom-mode' is toggled, when
+changing window or by calling `darkroom-set-margins'"
+ :type 'float
+ :group 'darkroom)
+
+(defcustom darkroom-text-scale-increase 2
+ "Steps to increase text size when in `darkroom-mode'.
+Value is passed to `text-scale-increase'."
+ :type 'integer
+ :group 'darkroom)
+
+(defcustom darkroom-fringes-outside-margins t
+ "If non-nil use fringes outside margins for `darkroom-mode'"
+ :type 'boolean
+ :group 'darkroom)
+
+(defcustom darkroom-margin-increment 0.05
+ "Increment to add used in `darkroom-increase-margins'."
+ :type 'float
+ :group 'darkroom)
+
+(defun darkroom-compute-margins ()
+ (or darkroom-buffer-margins
+ (cond ((functionp darkroom-margins)
+ (funcall darkroom-margins))
+ ((consp darkroom-margins)
+ darkroom-margins)
+ ((and (floatp darkroom-margins)
+ (< darkroom-margins 1))
+ (let ((delta (darkroom-float-to-columns darkroom-margins)))
+ (cons delta delta))))))
(defun darkroom-float-to-columns (f)
(ceiling (* (let ((edges (window-edges)))
(- (nth 2 edges) (nth 0 edges)))
f)))
+(defvar darkroom-buffer-margins nil
+ "Buffer-local version of `darkroom-margins' defcustom.
+Set by `darkroom-set-margins'")
+
(defun darkroom-set-margins (&optional margins)
- "Adjust margins to `darkroom-margins' or optional MARGINS."
- (let ((margins
- (or margins
- (darkroom-margins))))
+ "Set margins from MARGINS or `darkroom-compute-margins'."
+ (let* ((window-configuration-change-hook nil))
(when margins
- (set-window-margins (selected-window) (car margins) (cdr margins)))))
-
-(defun darkroom-increase-margins ()
- (interactive)
- (when (floatp darkroom-margins)
- (setq darkroom-margins (+ 0.05 darkroom-margins))
- (darkroom-set-margins)))
-
-(defun darkroom-decrease-margins ()
- (interactive)
- (when (floatp darkroom-margins)
- (setq darkroom-margins (- darkroom-margins 0.05))
- (darkroom-set-margins)))
-
-(defun darkroom-confirm-fill-paragraph ()
- (interactive)
- (when (yes-or-no-p "Really fill paragraph?")
- (call-interactively 'fill-paragraph)))
-
-(defvar darkroom-minor-mode-map (let ((map (make-sparse-keymap)))
- (define-key map (kbd "C-M-+") 'darkroom-increase-margins)
- (define-key map (kbd "C-M--") 'darkroom-decrease-margins)
- (define-key map (kbd "M-q") 'darkroom-confirm-fill-paragraph)
- map))
+ (when (null (car margins)) (setcar margins 0))
+ (when (null (cdr margins)) (setcdr margins 0)))
+ (set (make-local-variable 'darkroom-buffer-margins)
+ (or margins (darkroom-compute-margins)))
+ (walk-windows #'(lambda (w)
+ (when (eq (window-buffer w) (current-buffer))
+ (setq fringes-outside-margins
+ darkroom-fringes-outside-margins)
+ ;; See description of
+ ;; `fringes-outside-margins' for the reason
+ ;; for this apparent noop
+ (set-window-buffer w (current-buffer))
+ (set-window-margins w (car darkroom-buffer-margins)
+ (cdr darkroom-buffer-margins))))
+ nil
+ 'all-frames)))
+
+(defun darkroom-increase-margins (increment)
+ (interactive (list darkroom-margin-increment))
+ (unless (and (consp darkroom-buffer-margins)
+ (numberp (car darkroom-buffer-margins))
+ (numberp (cdr darkroom-buffer-margins)))
+ (error "`darkroom-buffer-margins' corrupted. Must be a cons of numbers."))
+ (setcar darkroom-buffer-margins
+ (round (* (+ 1 increment) (car darkroom-buffer-margins))))
+ (setcdr darkroom-buffer-margins
+ (round (* (+ 1 increment) (cdr darkroom-buffer-margins))))
+ (darkroom-set-margins darkroom-buffer-margins))
+
+(defun darkroom-decrease-margins (decrement)
+ (interactive (list darkroom-margin-increment))
+ (darkroom-increase-margins (- decrement)))
+
+(defvar darkroom-mode-map
+ (let ((map (make-sparse-keymap)))
+ (define-key map (kbd "C-M-+") 'darkroom-increase-margins)
+ (define-key map (kbd "C-M--") 'darkroom-decrease-margins)
+ map))
(defvar darkroom-saved-mode-line-format nil)
-(defvar darkroom-saved-visual-mode nil)
-(define-minor-mode darkroom-minor-mode
- "A minor mode that emulates the darkroom editor."
- nil
- " dark"
- nil
- (cond (darkroom-minor-mode
- (setq darkroom-saved-mode-line-format mode-line-format
- mode-line-format nil)
- (setq fringes-outside-margins darkroom-fringes-outside-margins)
- (add-hook 'window-configuration-change-hook 'darkroom-set-margins nil t)
- (darkroom-set-margins)
- (setq header-line-format t)
- ;; a hack shoulnd't be needed but apparently is
- (set-window-buffer (selected-window) (current-buffer))
- (when darkroom-turns-on-visual-line-mode
- (visual-line-mode 1)))
+(defvar darkroom-saved-header-line-format nil)
+(defvar darkroom-saved-margins nil)
+
+(define-minor-mode darkroom-mode
+ "Remove visual distractions and focus on writing.
+When this mode is active, everything but the buffer's text is
+elided from view. The buffer margins are set so that text is
+centered on screen. Text size is increased (display engine
+allowing) by `darkroom-text-scale-increase'." nil nil nil
+(cond (darkroom-mode
+ (set (make-local-variable 'darkroom-saved-mode-line-format)
+ mode-line-format)
+ (set (make-local-variable 'darkroom-saved-header-line-format)
+ header-line-format)
+ (set (make-local-variable 'darkroom-saved-margins) (window-margins))
+ (setq mode-line-format nil)
+ (setq header-line-format nil)
+ (darkroom-set-margins)
+ (text-scale-increase darkroom-text-scale-increase)
+ (add-hook 'window-configuration-change-hook 'darkroom-set-margins
+ nil t))
+ (t
+ (setq mode-line-format darkroom-saved-mode-line-format
+ header-line-format darkroom-saved-header-line-format)
+ (text-scale-decrease 2)
+ (let (darkroom-buffer-margins)
+ (darkroom-set-margins darkroom-saved-margins))
+ (remove-hook 'window-configuration-change-hook 'darkroom-set-margins
+ t))))
+
+(defun darkroom-maybe-enable ()
+ (cond ((and (not darkroom-mode) (= (count-windows) 1))
+ (darkroom-mode 1))
+ ((and darkroom-mode (> (count-windows) 1))
+ (darkroom-mode -1))
(t
- (setq header-line-format nil)
- (setq mode-line-format darkroom-saved-mode-line-format)
- (when darkroom-turns-on-visual-line-mode
- (visual-line-mode -1))
- (remove-hook 'window-configuration-change-hook 'darkroom-set-margins t)
- (set-window-margins (selected-window) 0 0))))
-
+ ;; (message "debug: buffer: %s windows: %s darkroom-mode: %s"
+ ;; (current-buffer) (count-windows) darkroom-mode)
+ )))
+
+
+(define-minor-mode darkroom-tentative-mode
+ "Minor mode that enters `darkroom-mode' when all windws are deleted"
+ nil "DarkroomT" nil
+ (cond (darkroom-tentative-mode
+ (add-hook 'window-configuration-change-hook
+ 'darkroom-maybe-enable nil t)
+ (darkroom-maybe-enable))
+ (t
+ (if darkroom-mode (darkroom-mode -1))
+ (remove-hook 'window-configuration-change-hook
+ 'darkroom-maybe-enable t))))
(provide 'darkroom)
+;;; darkroom.el ends here