;;; writeroom-mode.el --- Minor mode for distraction-free writing -*- lexical-binding: t -*-
;; Copyright (c) 2012-2017 Joost Kremers
;; Author: Joost Kremers <joostkremers@fastmail.fm>
;; Maintainer: Joost Kremers <joostkremers@fastmail.fm>
;; Created: 11 July 2012
;; Package-Requires: ((emacs "24.1") (visual-fill-column "1.9"))
;; Version: 3.7
;; Keywords: text
;; Redistribution and use in source and binary forms, with or without
;; modification, are permitted provided that the following conditions
;; are met:
;;
;; 1. Redistributions of source code must retain the above copyright
;; notice, this list of conditions and the following disclaimer.
;; 2. Redistributions in binary form must reproduce the above copyright
;; notice, this list of conditions and the following disclaimer in the
;; documentation and/or other materials provided with the distribution.
;; 3. The name of the author may not be used to endorse or promote products
;; derived from this software without specific prior written permission.
;;
;; THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
;; IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
;; OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
;; IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
;; INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
;; NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES ; LOSS OF USE,
;; DATA, OR PROFITS ; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
;; THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
;; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
;; THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
;;; Commentary:
;; writeroom-mode is a minor mode for Emacs that implements a
;; distraction-free writing mode similar to the famous Writeroom editor for
;; OS X. writeroom-mode is meant for GNU Emacs 24 and isn't tested on older
;; versions.
;;
;; See the README or info manual for usage instructions.
;;
;;; Code:
(require 'visual-fill-column)
(defvar writeroom--frame nil
"The frame in which `writeroom-mode' is activated.
The global effects only apply to this frame.")
(defvar writeroom--buffers nil
"List of buffers in which `writeroom-mode' is activated.")
(defvar writeroom--local-variables '(mode-line-format
header-line-format
line-spacing)
"Local variables whose values need to be saved when `writeroom-mode' is activated.")
(defvar writeroom--saved-data nil
"Buffer-local data to be stored when `writeroom-mode' is activated.
These settings are restored when `writeroom-mode' is
deactivated.")
(make-variable-buffer-local 'writeroom--saved-data)
(defvar writeroom--saved-visual-fill-column nil
"Status of `visual-fill-column-mode' before activating `writeroom-mode'.")
(make-variable-buffer-local 'writeroom--saved-visual-fill-column)
(defvar writeroom--saved-window-config nil
"Window configuration active before `writeroom-mode' is activated.")
(defgroup writeroom nil "Minor mode for distraction-free writing."
:group 'wp
:prefix "writeroom-")
(defcustom writeroom-width 80
"Width of the writeroom writing area.
This can be specified as an absolute width (the number of
characters in a line), or as a fraction of the total window
width, in the latter it should be a number between 0 and 1."
:group 'writeroom
:type '(choice (integer :tag "Absolute width:")
(float :tag "Relative width:" :value 0.5)))
(defcustom writeroom-mode-line nil
"The mode line format to use with `writeroom-mode'.
By default, this option is set to nil, which disables the mode
line when `writeroom-mode' is activated. By setting this option
to t, the standard mode line is retained. Alternatively, it is
possible to specify a special mode line for `writeroom-mode'
buffers. If this option is chosen, the default is to only show
the buffer's modification status and the buffer name, but the
format can be customized. See the documentation for the variable
`mode-line-format' for further information. Note that if you set
this option, it may be more visually pleasing to set
`writeroom-bottom-divider-width' to 0."
:group 'writeroom
:type '(choice (const :tag "Disable the mode line" nil)
(const :tag "Use default mode line" t)
(sexp :tag "Customize mode line"
:value (" " mode-line-modified " " mode-line-buffer-identification))))
(defcustom writeroom-mode-line-toggle-position 'header-line-format
"Position to temporarily show the mode line.
When the mode line is disabled, the function
`writeroom-toggle-mode-line' makes the mode line visible. This
option determines whether it is shown as the mode line or as the
header line."
:group 'writeroom
:type '(choice (const :tag "Use the mode line" 'mode-line-format)
(const :tag "Use the header line" 'header-line-format)))
(defcustom writeroom-bottom-divider-width 1
"Width of the bottom window divider in pixels."
:group 'writeroom
:type '(integer :tag "Width"))
(make-obsolete-variable 'writeroom-disable-fringe
"The variable `writeroom-disable-fringe' is no longer used."
"`writeroom-mode' version 2.9")
(defcustom writeroom-maximize-window t
"Whether to maximize the current window in its frame.
When set to t, `writeroom-mode' deletes all other windows in
the current frame."
:group 'writeroom
:type '(choice (const :tag "Maximize window" t)
(const :tag "Do not maximize window" nil)))
(defcustom writeroom-fullscreen-effect 'fullboth
"Effect applied when enabling fullscreen.
The value can be `fullboth', in which case fullscreen is
activated, or `maximized', in which case the relevant frame is
maximized but window decorations are still available."
:group 'writeroom
:type '(choice (const :tag "Fullscreen" fullboth)
(const :tag "Maximized" maximized)))
(defcustom writeroom-border-width 30
"Width in pixels of the border.
To use this option, select the option \"Add border\" in `Global
Effects'. This adds a border around the text area."
:group 'writeroom
:type '(integer :tag "Border width"))
(defcustom writeroom-fringes-outside-margins t
"If set, place the fringes outside the margins."
:group 'writeroom
:type '(choice (const :tag "Place fringes outside margins" t)
(const :tag "Place fringes inside margins" nil)))
(defcustom writeroom-major-modes '(text-mode)
"List of major modes in which writeroom-mode is activated.
The command `global-writeroom-mode' activates `writeroom-mode' in
every buffer that has one of the major modes listed in this
option. Modes can be specified as symbols or as regular
expressions. If a buffer has one of the specified major modes or
if its major mode name matches one of the regular expressions,
`writeroom-mode' is activated."
:group 'writeroom
:type '(repeat (choice (symbol :tag "Major mode")
(string :tag "Regular expression"))))
(defcustom writeroom-use-derived-modes t
"Activate `writeroom-mode' in derived modes as well.'.
If this option is set, the command `global-writeroom-mode'
activates `writeroom-mode' in modes that are derived from those
listed in `writeroom-major-modes'. Note that this option applies
only to symbols in `writeroom-major-modes'. Regular expressions
are ignored."
:group 'writeroom
:type '(choice (const :tag "Use derived modes" t)
(const :tag "Do not use derived modes" nil)))
(defcustom writeroom-major-modes-exceptions nil
"List of major modes in which `writeroom-mode' should not be activated.
This option lists exceptions to `writeroom-major-modes'. Modes
can be specified as symbols or as regular expressions."
:group 'writeroom
:type '(repeat (choice (symbol :tag "Major mode exception")
(string :tag "Regular expression"))))
(defcustom writeroom-restore-window-config nil
"If set, restore window configuration after disabling `writeroom-mode'.
Setting this option makes sense primarily if `writeroom-mode' is
used in one buffer only. The window configuration that is stored
is the one that exists when `writeroom-mode' is first called, and
it is restored when `writeroom-mode' is deactivated in the last
buffer."
:group 'writeroom
:type '(choice (const :tag "Do not restore window configuration" nil)
(const :tag "Restore window configuration" t)))
(defcustom writeroom-extra-line-spacing nil
"Additional line spacing for `writeroom-mode`."
:group 'writeroom
:type '(choice (const :tag "Do not add extra line spacing" :value nil)
(integer :tag "Absolute height" :value 5)
(float :tag "Relative height" :value 0.8)))
(defcustom writeroom-global-effects '(writeroom-set-fullscreen
writeroom-set-alpha
writeroom-set-menu-bar-lines
writeroom-set-tool-bar-lines
writeroom-set-vertical-scroll-bars
writeroom-set-bottom-divider-width)
"List of global effects for `writeroom-mode'.
These effects are enabled when `writeroom-mode' is activated in
the first buffer and disabled when it is deactivated in the last
buffer."
:group 'writeroom
:type '(set (const :tag "Fullscreen" writeroom-set-fullscreen)
(const :tag "Disable transparency" writeroom-set-alpha)
(const :tag "Disable menu bar" writeroom-set-menu-bar-lines)
(const :tag "Disable tool bar" writeroom-set-tool-bar-lines)
(const :tag "Disable scroll bar" writeroom-set-vertical-scroll-bars)
(const :tag "Enable bottom window divider" writeroom-set-bottom-divider-width)
(const :tag "Add border" writeroom-set-internal-border-width)
(const :tag "Display frame on all workspaces" writeroom-set-sticky)
(repeat :inline t :tag "Custom effects" function)))
(define-obsolete-variable-alias 'writeroom-global-functions 'writeroom-global-effects "`writeroom-mode' version 2.0")
(defmacro define-writeroom-global-effect (fp value)
"Define a global effect for `writeroom-mode'.
The effect is activated by setting frame parameter FP to VALUE.
FP should be an unquoted symbol, the name of a frame parameter;
VALUE must be quoted (unless it is a string or a number, of
course). It can also be an unquoted symbol, in which case it
should be the name of a global variable whose value is then
assigned to FP.
This macro defines a function `writeroom-set-<FP>' that takes one
argument and activates the effect if this argument is 1 and
deactivates it if it is -1. When the effect is activated, the
original value of frame parameter FP is stored in a frame
parameter `writeroom-<FP>', so that it can be restored when the
effect is deactivated."
(declare (indent defun))
(let ((wfp (intern (format "writeroom-%s" fp))))
`(fset (quote ,(intern (format "writeroom-set-%s" fp)))
(lambda (&optional arg)
(when (frame-live-p writeroom--frame)
(cond
((= arg 1) ; activate
(set-frame-parameter writeroom--frame (quote ,wfp) (frame-parameter writeroom--frame (quote ,fp)))
(set-frame-parameter writeroom--frame (quote ,fp) ,value))
((= arg -1) ; deactivate
(set-frame-parameter writeroom--frame (quote ,fp) (frame-parameter writeroom--frame (quote ,wfp)))
(set-frame-parameter writeroom--frame (quote ,wfp) nil))))))))
(define-writeroom-global-effect fullscreen writeroom-fullscreen-effect)
(define-writeroom-global-effect alpha '(100 100))
(define-writeroom-global-effect vertical-scroll-bars nil)
(define-writeroom-global-effect menu-bar-lines 0)
(define-writeroom-global-effect tool-bar-lines 0)
(define-writeroom-global-effect internal-border-width writeroom-border-width)
(define-writeroom-global-effect sticky t)
(define-writeroom-global-effect bottom-divider-width writeroom-bottom-divider-width)
(defun turn-on-writeroom-mode ()
"Turn on `writeroom-mode'.
This function activates `writeroom-mode' in a buffer if that
buffer's major mode matchs against one of `writeroom-major-modes'."
(unless (writeroom--match-major-mode writeroom-major-modes-exceptions)
(if (writeroom--match-major-mode writeroom-major-modes writeroom-use-derived-modes)
(writeroom-mode 1))))
(defun writeroom--match-major-mode (modes &optional derived)
"Match the current buffer's major mode against MODES.
MODES a list of mode names (symbols) or regular expressions.
Return t if the current major mode matches one of the elements of
MODES, nil otherwise. Comparison is done with `eq` (for symbols
in MODES) or with `string-match-p' (for strings in MODES). That
is, if the major mode is e.g., `emacs-lisp-mode', it will not
match the symbol `lisp-mode', but it will match the string
\"lisp-mode\".
If DERIVED is non-nil, also return t if the current buffer's
major mode is a derived mode of one of the major mode symbols in
MODES."
(catch 'match
(dolist (elem modes)
(if (cond ((symbolp elem)
(or (eq elem major-mode)
(and derived (derived-mode-p elem))))
((string-match-p elem (symbol-name major-mode))))
(throw 'match t)))))
(defvar writeroom-mode-map
(let ((map (make-sparse-keymap)))
(define-key map (kbd "s-?") #'writeroom-toggle-mode-line)
map)
"Keymap for writeroom-mode.")
;;;###autoload
(define-minor-mode writeroom-mode
"Minor mode for distraction-free writing."
:init-value nil :lighter nil :global nil
(if writeroom-mode
(writeroom--enable)
(writeroom--disable)))
;;;###autoload
(define-globalized-minor-mode global-writeroom-mode writeroom-mode turn-on-writeroom-mode
:require 'writeroom-mode
:group 'writeroom)
(defun writeroom--kill-buffer-function ()
"Disable `writeroom-mode' before killing a buffer, if necessary.
This function is for use in `kill-buffer-hook'. It checks whether
`writeroom-mode' is enabled in the buffer to be killed and
adjusts `writeroom--buffers' and the global effects accordingly."
(when writeroom-mode
(setq writeroom--buffers (delq (current-buffer) writeroom--buffers))
(when (not writeroom--buffers)
(writeroom--set-global-effects -1)
(setq writeroom--frame nil))))
(add-hook 'kill-buffer-hook #'writeroom--kill-buffer-function)
(defun writeroom--set-global-effects (arg)
"Activate or deactivate global effects.
The effects are activated if ARG is 1, deactivated if it is -1."
(mapc (lambda (fn)
(funcall fn arg))
writeroom-global-effects))
(defun writeroom--calculate-width ()
"Calculate the width of the writing area."
(if (floatp writeroom-width)
(truncate (* (window-total-width) writeroom-width))
writeroom-width))
(defvar writeroom--mode-line-showing nil
"Flag indicating whether the original mode line is displayed.")
(make-variable-buffer-local 'writeroom--mode-line-showing)
(defvar writeroom--orig-header-line nil
"Original format of the header line.
When the header line is used to temporarily display the mode
line, its original format is saved here.")
(make-variable-buffer-local 'writeroom--orig-header-line)
(defun writeroom-toggle-mode-line ()
"Toggle display of the original mode."
(interactive)
(unless (eq writeroom-mode-line t) ; This means the original mode-line is displayed already.
(cond
((not writeroom--mode-line-showing)
(setq writeroom--orig-header-line header-line-format)
(set writeroom-mode-line-toggle-position (or (cdr (assq 'mode-line-format writeroom--saved-data))
(default-value 'mode-line-format)))
(setq writeroom--mode-line-showing t))
(writeroom--mode-line-showing
(if (eq writeroom-mode-line-toggle-position 'header-line-format)
(setq header-line-format writeroom--orig-header-line)
(setq mode-line-format writeroom-mode-line))
(setq writeroom--mode-line-showing nil)))
(force-mode-line-update)))
(defun writeroom-adjust-width (amount)
"Adjust the width of the writing area on the fly by AMOUNT.
A numeric prefix argument can be used to specify the adjustment.
When called without a prefix, this will reset the width to the default value."
(interactive "P")
(if amount
(setq visual-fill-column-width (max 1 (+ visual-fill-column-width amount)))
(setq visual-fill-column-width (writeroom--calculate-width)))
(visual-fill-column--adjust-window)
(message "Writing area is now %d characters wide" visual-fill-column-width))
(defun writeroom-increase-width ()
"Increase the width of the writing area by 2 characters."
(interactive)
(writeroom-adjust-width 2))
(defun writeroom-decrease-width ()
"Decrease the width of the writing area by 2 characters."
(interactive)
(writeroom-adjust-width -2))
(defun writeroom--enable ()
"Set up writeroom-mode for the current buffer.
Also run the functions in `writeroom-global-effects' if the
current buffer is the first buffer in which `writeroom-mode' is
activated."
;; save buffer-local variables, if they have a buffer-local binding
(setq writeroom--saved-data (mapcar (lambda (sym)
(if (local-variable-p sym)
(cons sym (buffer-local-value sym (current-buffer)))
sym))
writeroom--local-variables))
(setq writeroom--saved-visual-fill-column visual-fill-column-mode)
;; activate global effects
(when (not writeroom--buffers)
(setq writeroom--frame (selected-frame))
(writeroom--set-global-effects 1)
(if writeroom-restore-window-config
(setq writeroom--saved-window-config (current-window-configuration))))
(push (current-buffer) writeroom--buffers)
(when writeroom-maximize-window
(delete-other-windows))
(when writeroom-extra-line-spacing
(setq line-spacing writeroom-extra-line-spacing))
(unless (eq writeroom-mode-line t) ; if t, use standard mode line
(setq mode-line-format writeroom-mode-line))
(setq visual-fill-column-width (writeroom--calculate-width)
visual-fill-column-center-text t
visual-fill-column-fringes-outside-margins writeroom-fringes-outside-margins)
(visual-fill-column-mode 1)
;; if the current buffer is displayed in some window, the windows'
;; margins and fringes must be adjusted.
(mapc (lambda (w)
(with-selected-window w
(visual-fill-column--adjust-window)))
(get-buffer-window-list (current-buffer) nil)))
(defun writeroom--disable ()
"Reset the current buffer to its normal appearance.
Also run the functions in `writeroom-global-effects' to undo
their effects if `writeroom-mode' is deactivated in the last
buffer in which it was active."
;; disable visual-fill-column-mode
(visual-fill-column-mode -1)
(kill-local-variable 'visual-fill-column-width)
(kill-local-variable 'visual-fill-column-center-text)
(kill-local-variable 'visual-fill-column-fringes-outside-margins)
;; restore global effects if necessary
(setq writeroom--buffers (delq (current-buffer) writeroom--buffers))
(when (not writeroom--buffers)
(writeroom--set-global-effects -1)
(setq writeroom--frame nil)
(if writeroom-restore-window-config
(set-window-configuration writeroom--saved-window-config)))
;; restore local variables
(mapc (lambda (val)
(if (symbolp val)
(kill-local-variable val)
(set (car val) (cdr val))))
writeroom--saved-data)
;; if the current buffer is displayed in some window, the windows'
;; margins and fringes must be adjusted.
(mapc (lambda (w)
(with-selected-window w
(set-window-margins (selected-window) 0 0)
(set-window-fringes (selected-window) nil)))
(get-buffer-window-list (current-buffer) nil))
;; reenable `visual-fill-colummn-mode' with original settings if it was
;; active before activating `writeroom-mode'.
(if writeroom--saved-visual-fill-column
(visual-fill-column-mode 1)))
(provide 'writeroom-mode)
;;; writeroom-mode.el ends here