path: root/smart-documents.org

# -*- mode: org; -*-

#+TITLE: Smart Documents
#+AUTHOR: Marius Peter
#+DATE: <2021-02-09 Tue>
#+EMAIL: smart-documents@tuta.io

#+OPTIONS: html-style:nil
#+STARTUP: showall
# LaTeX setup
#+SETUPFILE: ~/.emacs.d/templates/documents/gnu-default.setup
# Title page
#+INCLUDE: ~/.emacs.d/templates/documents/default-title.org

#+LATEX_HEADER_EXTRA: \newfontfamily\garamond{EB Garamond}
#+LATEX_HEADER_EXTRA: \newfontfamily\publicsans{Public Sans}

#+LATEX: \begin{abstract}
The idea of /Smart Documents/ came to me as I was reflecting on how to
improve the document creation process in my workplace. The GNU Emacs
editor had captured my imagination, and I wanted to create an
accessible and highly productive text editor to benefit my
organization. In this paper, I'll lay out my vision for the /Smart
Document/, a file containing both text destined to the reader, and
code describing how to update, validate, and present this text; then,
I'll weave my personal GNU Emacs customizations with a tutorial. This
paper is a /Smart Document/ itself!
#+LATEX: \end{abstract}

* COMMENT All TODOs

** TODO Harmonize ~compagnon~ themes

* Introduction

The following sections were laid out very deliberately. When we start
Emacs, the source code blocks contained in this document are evaluated
sequentially---our editing environment is constructed in real time as
we execute the blocks in order. For instance, we only begin loading
packages once we ensured ~use-package~ is working properly.[fn::For
more information on the detailed steps Emacs takes upon starting,
refer to
[[https://www.gnu.org/software/emacs/manual/html_node/elisp/Startup-Summary.html]].]

Customizing Emacs goes far, far beyond rewriting sections of this
document---feel free to experiment and discover. Here are three
commands that will help you understand all the symbols in this file,
if you are browsing this paper within Emacs itself:

- ~C-h f~ :: describe function
- ~C-h v~ :: describe variable
- ~C-h k~ :: describe key

You can press ~f1~ at any time to access Emacs built-in help.

** TODO User details

One advantage of working with /Smart Documents/ is that they can
automatically be populated with our details in the header, footer, or
other appropriate element.

#+NAME: user-details-get
#+BEGIN_SRC emacs-lisp
  (setq user-full-name "Marius Peter")

  (defun my/user-details-get ()
    "Get user details."
    (interactive)
    (setq user-full-name (read-string "Enter full user name:"))
    (setq user-mail-address (read-string "Enter user e-mail address:"))
    (message "Successfully captured user details."))
#+END_SRC

#+NAME: user-details
#+BEGIN_SRC emacs-lisp
  (defun my/tokenize-user-details ()
    "Tokenize user details."

    (cons 'user-full-name user-full-name))

  (unless (file-exists-p (concat user-emacs-directory
                                 "meta/user-details"))
    (setq user-details '(user-full-name
                         user-mail-address))
    (append-to-file "Foobar\n" nil "~/.emacs.d/meta/foobar"))
#+END_SRC

** File system paths

In this subsection, we tell Emacs about relevant paths to resources.

On my MS Windows machine, I add the path to Portable Git.[fn::Download
from https://git-scm.com/download/win]

#+BEGIN_SRC emacs-lisp :tangle yes
  (when (string-equal system-type "windows-nt")
    (add-to-list 'exec-path "C:/Users/marius.peter/PortableGit/bin/"))
#+END_SRC

* Early setup

** The first file to load
:PROPERTIES:
:sd-unpack-path: init.el
:END:

The contents of this Section was automatically moved to
=~/.emacs.d/init.el=.  Use `sd-pack-section' to copy the contents back
into this section.

This is the very first user-editable file loaded by Emacs.[fn::This
feature became available in version 27.1.] In it, we disable GUI
elements that would otherwise be loaded and displayed once Emacs is
ready to accept user input.

It can be found here: [[file:early-init.el]]

** The second file to load
:PROPERTIES:
:sd-unpack-path: early-init.el
:END:

#+BEGIN_QUOTE
Traditionally, file =~/.emacs= is used as the init file, although
Emacs also looks at the following locations:

- =~/.emacs.el=
- =~/.emacs.d/init.el=
- =~/.config/emacs/init.el=.

From the GNU
website[fn::[[https://www.gnu.org/software/emacs/manual/html_node/emacs/Init-File.html]]]
#+END_QUOTE

This file can be found here: [[file:init.el]]

If no file is found, Emacs then loads in its purely vanilla state.

** Profiling---start

We start the profiler now , and will interrupt it in Section
[[Profiling---stop]]. We will then present profiling report in Section
[[Profiling---report]].

#+NAME: profiler-start
#+BEGIN_SRC emacs-lisp :tangle no
  (profiler-start)
#+END_SRC

** Jumping to this file

We begin by defining a function to open this very file.

#+NAME: shortcut-config
#+BEGIN_SRC emacs-lisp :tangle yes
  (defun my/find-literate-config ()
    "Jump to this very file."
    (interactive)
    (find-file my/literate-config))
#+END_SRC

** Definitions

*** Usual paths

This section defines the paths that structure the overall {{{sd}}}
logic.

#+BEGIN_SRC emacs-lisp :tangle yes
  (defcustom sd-path-meta
    (concat user-emacs-directory "meta/")
    "Directory containing the meta files.")

  (defcustom sd-path-res
    (concat user-emacs-directory "res/")
    "Directory containing the third-party resources.")
#+END_SRC

** Resources

All third-party resources are saved at the following location.

*** Packages

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq package-user-dir
        (concat sd-path-res
                "elpa"))
#+END_SRC

*** Emojis

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq emojify-emojis-dir
        (concat sd-path-res
                "emojis"))
#+END_SRC

** Meta-files

In this section, we'll be tidying up the =.emacs.d/= directory---by
default, many Emacs packages create files useful for themselves in our
~user-emacs-directory~. This leads to undesirable clutter. Certain
packages create files that log recently visited files ([[Recently
visited files]]); log location of known projects ([[Projects' bookmarks]]);
log location in recently visited files ([[Location in previously visited
file]]) The commonality between all these files is that they tend to
reference... other files. Thus, I decided to refer to them as
meta-files.

*** Recently visited files

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq recentf-save-file
        (concat
         sd-path-meta
         "recentf"))
#+END_SRC

*** Projects' bookmarks

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq projectile-known-projects-file
        (concat
         sd-path-meta
         "projectile-bookmarks.eld"))
#+END_SRC

*** Location in previously visited file

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq save-place-file
        (concat
         sd-path-meta
         "places"))
#+END_SRC

*** Auto save file lists

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq auto-save-list-file-prefix
        (concat sd-path-meta
                "auto-save-list/.saves-"))
#+END_SRC

** Custom file

Load settings created automatically by GNU Emacs Custom. (For example,
any clickable option/toggle is saved here.) Useful for fooling around
with ~M-x customize-group <package>~.

#+NAME: custom-file-location
#+BEGIN_SRC emacs-lisp :tangle yes
  (setq custom-file (concat user-emacs-directory "custom.el"))
  (load custom-file)
#+END_SRC

** Backups

Backups are very important!

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq backup-directory-alist
        `((".*" . ,temporary-file-directory))
        auto-save-file-name-transforms
        `((".*" ,temporary-file-directory t))
        backup-by-copying t    ; Don't delink hardlinks
        version-control t      ; Use version numbers on backups
        delete-old-versions t  ; Automatically delete excess backups
        kept-new-versions 20   ; how many of the newest versions to keep
        kept-old-versions 5)   ; and how many of the old
#+END_SRC

** Initial and default frames

We set the dimensions of the initial frame:

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-to-list 'initial-frame-alist '(width  . 70))
  (add-to-list 'initial-frame-alist '(height . 40))
#+END_SRC

We also set the dimensions of subsequent frames:

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-to-list 'default-frame-alist '(width  . 70))
  (add-to-list 'default-frame-alist '(height . 40))
#+END_SRC

Transparency.

: (set-frame-parameter (selected-frame) 'alpha '(<active> . <inactive>))
: (set-frame-parameter (selected-frame) 'alpha <both>)

#+BEGIN_SRC emacs-lisp :tangle yes
  (set-frame-parameter (selected-frame) 'alpha '(95 . 70))
  (add-to-list 'default-frame-alist '(alpha . (95 . 70)))
#+END_SRC

** Secrets

The code contained in the =secrets.org= file is loaded by Emacs, but
not rendered in this PDF for the sake of privacy. It contains
individually identifying information such as names and e-mail
addresses, which are used to populate Org templates (Section
[[~org-mode~]]). You need to create this =secrets.org= file, as it is
ignored by =git= by default.

#+BEGIN_SRC emacs-lisp :tangle yes
  (let ((secrets (concat user-emacs-directory "secrets.org")))
    (when (file-exists-p secrets) (org-babel-load-file secrets)))
#+END_SRC

* Keyboard shortcuts

What follows are the most useful keybindings, as well as the
keybindings to the functions we defined ourselves. It doesn't matter
if we haven't defined the functions themselves yet; Emacs will accept
a keybinding for any symbol and does not check if the symbol's
function definition exists, until the keybinding is pressed.

** CUA mode

The following bindings strive to further enhance CUA mode.[fn::Common
User Access. This is a term coined by IBM which has influenced user
navigation cues on all modern desktop OSes. From IBM's CUA, we get the
=Ctrl-c= and =Ctrl-v= keyboard shortcuts.]

#+BEGIN_SRC emacs-lisp :tangle yes
  (cua-mode)
#+END_SRC

** Files

*** Save a file

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-s") 'save-buffer)
#+END_SRC

*** Open a file

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-o") 'find-file)
#+END_SRC

*** List open files

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-b") 'ivy-switch-buffer)
#+END_SRC

*** Open this very file

(Function defined in Section [[Jumping to this file]])

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-c c") 'my/find-literate-config)
#+END_SRC

*** Open a recently visited file

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-r") 'counsel-recentf)
#+END_SRC

*** Locate a file

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-c l") 'counsel-locate)
#+END_SRC

*** Open the agenda

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-c a") 'org-agenda)
#+END_SRC

*** Open the diary
# SSH headache with lws VPS
#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key [f9]
                  '(lambda ()
                     "Load `org-agenda-diary-file'."
                     (interactive)
                     (find-file org-agenda-diary-file)))
#+END_SRC

*** Open Org mode document properties

#+BEGIN_SRC emacs-lisp :tangle no
  (global-set-key [f9] 'sd-document-properties)
#+END_SRC

** Windows

*** Close window and quit

The following bindings lead to more natural window & frame exit behaviors.

#+NAME: close-window-or-previous-buffer
#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-w") 'sd-delete-window-or-previous-buffer)
#+END_SRC

** Frame

*** Make new frame

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-n") 'make-frame)
#+END_SRC

*** Make only frame

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-`") 'delete-other-windows)
#+END_SRC

*** Delete frame or kill Emacs

#+NAME: delete-frame-or-kill-emacs
#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-q") 'sd-delete-frame-or-kill-emacs)
#+END_SRC

*** Remap =C-z= when using a graphical interface

By default, =C-z= suspends the editor. This is extremely handy when
the editor is started with the =-nw= option (no window, i.e. launched
in a terminal), because it returns control to the terminal command
line without quitting Emacs---it simply places the Emacs process in
the background.  The user may then use the Linux job management tools
to return inside the Emacs process.

However, when using a graphical display, we have no need for
suspending the frame, so we remap =C-z= to the much more sensible
~undo~ behaviour.

#+BEGIN_SRC emacs-lisp :tangle yes
  (when (display-graphic-p)
    (global-set-key (kbd "C-z") 'undo))
#+END_SRC

** Text display

*** Zoom

The typical binding on both GNU/Linux and MS Windows is adequate here:
~C-=~ to zoom in, ~C--~ to zoom out.

It seems that starting with Emacs 27.1, Control + mousewheel works.

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C--") 'text-scale-decrease)
  (global-set-key (kbd "C-=") 'text-scale-increase)
  (global-set-key (kbd "C-+") 'text-scale-increase)
#+END_SRC

** TODO Navigation

=Alt= (=Meta=) is the privileged key for motion in a buffer. It is
followed by an optional numerical argument, and a movement
command. You may navigate in a buffer by keeping =Alt= pressed,
optionally inputting a number from the keypad or number row, then
pressing any of the following movement keys: =j=, =k=, =h=, and
=l=. You will move in that direction in the amount of the numerical
argument.

#+NAME: keybinding-navigation
#+CAPTION[Navigation keybindings]: Navigation keybindings.
#+ATTR_LATEX: :booktabs t
|           | *Backwards* | *Forwards* |
|-----------+-------------+------------|
| Character | =M-h=       | =M-l=      |
| Line      | =M-k=       | =M-j=      |
| Word      | =M-f=       | =M-b=      |
| Paragraph | =M-a=       | =M-e=      |

We prevent Org mode from overriding preferred navigation keys.

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-hook 'org-mode
            '(lambda ()
               (local-unset-key (kbd "M-j"))
               (local-unset-key (kbd "M-k"))
               (local-unset-key (kbd "M-l"))
               (local-unset-key (kbd "M-h"))))
#+END_SRC

*** Move down one line

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "M-j") 'next-line)
#+END_SRC

*** Move up one line

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "M-k") 'previous-line)
#+END_SRC

*** Move left one character

#+BEGIN_SRC emacs-lisp :tangle yes
  (local-unset-key (kbd "M-h"))
  (global-set-key (kbd "M-h") 'left-char)
#+END_SRC

*** Move right one character

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "M-l") 'right-char)
#+END_SRC

** Accessing customization

*** Customize a variable

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-c v") 'customize-variable)
#+END_SRC

*** Customize a face

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-c f") 'customize-face)
#+END_SRC

** One-click workflows

A major advantage of the Emacs document production system: arbitrarily
complicated functions can be assigned to very simple keybindings. This
means we can automate workflows up to a pretty absurd level.

*** Export to PDF

PDF is probably the most prevalent file format for sharing static
documents.

**** Document

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key (kbd "C-p") 'sd-quick-export)
#+END_SRC

**** TODO Presentation

#+BEGIN_SRC emacs-lisp :tangle yes

#+END_SRC

*** Clean up buffer

Clean up buffer in every mode.

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-set-key [f12] 'sd-beautify-buffer)
#+END_SRC

* Packages

Packages are collections of =.el= files providing added functionality
to Emacs.

** Meta

How do we bootstrap packages? First, let's figure out:

1. Where we get our packages from
2. How we upgrade packages
3. How we ensure our required packages are installed

*** Package archives

List of package archives.

#+NAME: package-archives
#+BEGIN_SRC emacs-lisp :tangle yes
  (require 'package)
  (add-to-list 'package-archives '("melpa" . "https://melpa.org/packages/") t)
  (add-to-list 'package-archives '("org" . "https://orgmode.org/elpa/") t)
  (package-initialize)
#+END_SRC

*** TODO Convenient package update

One-function rollup of upgradeable package tagging, download and lazy
install.

#+BEGIN_SRC emacs-lisp :tangle yes

#+END_SRC

*** ~use-package~

We ensure =use-package= is installed, as well as all packages
described in this configuration file.

#+BEGIN_SRC emacs-lisp :tangle yes
  (unless (package-installed-p 'use-package)
    (package-refresh-contents)
    (package-install 'use-package)
    (eval-when-compile (require 'use-package)))
  (setq use-package-always-ensure t)
  (require 'use-package)
  (require 'bind-key)
#+END_SRC

** ~evil-mode~

Forgive me, for I have sinned.

This is the 2^{nd} most significant customization after
~org-mode~. Enabling ~evil-mode~ completely changes editing
keys.[fn::For more information on =vi= keybindings, visit
[[https://hea-www.harvard.edu/~fine/Tech/vi.html]].]

#+BEGIN_SRC emacs-lisp :tangle no
  (use-package evil)
  (setq evil-toggle-key "C-c d")
  (evil-mode 1)
#+END_SRC

** Spelling, completion, and snippets

The following customizations open the doors to vastly increased
typing speed and accuracy.

*** Syntax checking

We require a package to highlight syntax errors and warnings. The
~flycheck~ package ensures we are aware of all our code's syntactical
shortcomings.

#+NAME: flycheck
#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package flycheck)
  (global-flycheck-mode)
#+END_SRC

*** Spelling

#+NAME: flyspell
#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package flyspell)
  (add-hook 'text-mode-hook 'flyspell-mode)
#+END_SRC

*** Completion

#+BEGIN_SRC emacs-lisp :tangle no
  (use-package company)
  (add-hook 'after-init-hook 'global-company-mode)
#+END_SRC

*** Insert template from keyword

Thanks to ~yasnippet~, we can type certain keywords, then press =TAB=,
to automatically insert a predefined text snippet. We can then
navigate through the snippet by using =<tab>= (next field) and
=<backtab>= (previous field).[fn::=<backtab>= is synonymous with
pressing shift-tab.]

For instance: typing =src= then pressing =TAB= will expand the keyword
to the following text:

: #+BEGIN_SRC emacs-lisp :tangle yes
:
: #+END_SRC

We notice that emacs-lisp is highlighted---this is the first
modifiable field. Many clever programming tricks can be performed with
~yasnippet~ to save us a ton of time with boilerplate text!

#+NAME: yasnippet
#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package yasnippet)
  (yas-global-mode 1)
#+END_SRC

*** Delete all consecutive whitespaces

#+NAME: hungry-delete
#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package hungry-delete)
  (global-hungry-delete-mode)
#+END_SRC

** Utilities

*** Versioning of files

Wonderful Git porcelain for Emacs. Enables the administration of a Git
repository in a pain-free way.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package magit
    :bind ("C-c g" . magit-status))
#+END_SRC

*** Navigate between projects

This enables us to better manage our =.git= projects.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package projectile
    :bind ("C-c p" . 'projectile-command-map)
    :init (projectile-mode 1)
    (setq projectile-completion-system 'ivy))
#+END_SRC

*** Display keyboard shortcuts on screen

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package which-key
    :init (which-key-mode))
#+END_SRC

*** Jump to symbol's definition

~dumb-jump~ is a reliable symbol definition finder. It uses different
matching algorithms and heuristics to provide a very educated guess on
the location of a symbol's definition.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package dumb-jump)
  (add-hook 'xref-backend-functions #'dumb-jump-xref-activate)
#+END_SRC

*** Graphical representation of file history

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package undo-tree)
  (global-undo-tree-mode)
#+END_SRC

*** Auto-completion framework

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package ivy
    :config (setq ivy-use-virtual-buffers t
                  ivy-count-format "%d/%d "
                  enable-recursive-minibuffers t))
  (ivy-mode t)
#+END_SRC

**** Smartly suggesting interactive search matches

And he will be called Wonderful *Counselor*, Mighty God,
Everlasting Father, Prince of Peace.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package counsel
    :bind ("M-x" . counsel-M-x)
    :config (counsel-mode t))
#+END_SRC

**** Searching for items in current buffer

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package swiper
    :bind (("C-f" . swiper)))
#+END_SRC

*** Web browsing

Thanks
Xah![fn::[[http://ergoemacs.org/emacs/emacs_set_default_browser.html]]]

#+BEGIN_SRC emacs-lisp :tangle yes
  ;; use browser depending on url
  (setq
   browse-url-browser-function
   '(
     ("wikipedia\\.org" . browse-url-firefox)
     ("github" . browse-url-chromium)
     ("thefreedictionary\\.com" . eww-browse-url)
     ("." . browse-url-default-browser)
     ))
#+END_SRC

*** IRC

Emacs ships with an IRC client called ~erc~.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package erc
    :custom
    (erc-autojoin-channels-alist '(("freenode.net"
                                    "#linux"
                                    "#archlinux"
                                    "#emacs"
                                    "#bitcoin"
                                    "#latex"
                                    "#org-mode"
                                    "#python")))
    (erc-autojoin-timing 'ident) ; Autojoin after NickServ identification.
    (erc-fill-function 'erc-fill-static)
    (erc-fill-static-center 16)
    ;; (erc-hide-list '("JOIN" "PART" "QUIT"))
    (erc-lurker-hide-list '("JOIN" "PART" "QUIT"))
    (erc-lurker-threshold-time (* 3600 4)) ; Four hours
    (erc-prompt-for-nickserv-password nil)
    (erc-server-reconnect-attempts 5)
    (erc-server-reconnect-timeout 3)
    :config
    (add-to-list 'erc-modules 'spelling)
    (erc-services-mode 1)
    (erc-update-modules))
#+END_SRC

*** TODO Telegram

Yeah, a Telegram client exists for Emacs.

#+BEGIN_SRC emacs-lisp :tangle no
  (use-package telega
    :load-path "~/telega.el/telega.el"
    :commands (telega)
    :defer t)
#+END_SRC

*** Drawings



#+BEGIN_SRC ditaa :file img/ditaa.png
  +-----------+    +-----------------+
  | c06F      |    | c06F            |
  | Create a  |    | Open the source |
  | source    |--->| block and       |
  | block for |    | start drawing!  |
  | ditaa     |    |                 |
  +-----------+    +-----------------+
#+END_SRC

#+RESULTS:
[[file:img/ditaa.png]]

*** TODO UML diagrams
# Implement automatically downloading this kind of executable!

#+BEGIN_SRC emacs-lisp :tangle yes
  (require 'plantuml-mode)

  (setq plantuml-default-exec-mode 'jar
        plantuml-jar-path (concat user-emacs-directory
                                  "execs/plantuml.jar")
        org-plantuml-jar-path (concat user-emacs-directory
                                      "execs/plantuml.jar"))
#+END_SRC

#+BEGIN_SRC plantuml :file img/uml.png
  @startuml doob.png
  !theme cerulean-outline
  title Example diagram with Plantuml

  package "Package 1" as pkg1 {
          node node1
          node node2
  }
  package "Package 2" as pkg2 {
          component "Component 1" as comp1
          component "Component 2" as comp2
          interface "Interface" as int
  }

  pkg1 .. pkg2

  comp1 --> int
  comp2 --> int
  @enduml
#+END_SRC

#+RESULTS:
[[file:img/uml.png]]

** Coding languages

*** TODO Emacs Lisp

*** Python

Python is included by default on most Linux distributions.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package py-yapf)
  (add-hook 'python-mode-hook 'py-yapf-enable-on-save)
#+END_SRC

*** Haskell

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package haskell-mode)
#+END_SRC

** File formats

These aren't tied to a particular language per se.

***  =csv= and Excel

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package csv-mode)
#+END_SRC

*** Interacting with PDFs

Org mode shines particularly when exporting to PDF---Org files can
reliably be shared and exported to PDF in a reproducible fashion.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package pdf-tools)
  (pdf-tools-install)
#+END_SRC

*** Accounting

Ledger is a creation of John Wiegley's. It enables double-entry
accounting in a simple plaintext format, and reliable verification of
account balances through time.[fn::For more information, visit
https://www.ledger-cli.org/.]

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package ledger-mode
    :bind
    ("C-c r" . ledger-report)
    ("C-c C" . ledger-mode-clean-buffer))
#+END_SRC

These reports can be generated within Emacs. It is quite useful to
pipe their output to an automated ``smart document''.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq ledger-reports
        '(("bal" "%(binary) -f %(ledger-file) bal")
          ("bal-USD" "%(binary) -f %(ledger-file) bal --exchange USD")
          ("reg" "%(binary) -f %(ledger-file) reg")
          ("net-worth" "%(binary) -f %(ledger-file) bal ^Assets ^Liabilities --exchange USD")
          ("net-income" "%(binary) -f %(ledger-file) bal ^Income ^Expenses --exchange USD --depth 2 --invert")
          ("payee" "%(binary) -f %(ledger-file) reg @%(payee)")
          ("account" "%(binary) -f %(ledger-file) reg %(account)")
          ("budget" "%(binary) -f %(ledger-file) budget --exchange USD")))
#+END_SRC

*** Plotting & charting

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package gnuplot)
#+END_SRC

** Cosmetics

*** Start page

We replace the standard welcome screen with our own.

#+BEGIN_SRC emacs-lisp :tangle yes

#+END_SRC

*** Better parentheses

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package rainbow-delimiters
    :config (add-hook 'prog-mode-hook #'rainbow-delimiters-mode))
  (show-paren-mode 1)
#+END_SRC

*** Highlight /color/ keywords in that color

This highlights hexadecimal numbers which look like colors, in that
same color.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package rainbow-mode
    :init
    (add-hook 'prog-mode-hook 'rainbow-mode))
#+END_SRC

*** Minor modes in mode line

We hide minor modes in the mode line.

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package rich-minority)
  (rich-minority-mode 1)
  (setf rm-whitelist "projectile")
#+END_SRC

*** Emojis

Emojis are a symbol of modernity, and their tasteful use enables
communicating with people from around the world---we're all for that!
B-) \smiley

#+BEGIN_SRC emacs-lisp :tangle yes
  (when (string-equal system-type "gnu/linux")
    (use-package emojify
      :hook (after-init . global-emojify-mode)))
#+END_SRC

* ~org-mode~

Org mode is so significant that this section of the paper deserves its
own introduction.

** Introduction

Phew, after all this initialization, I can finally introduce Org mode!
I am so *excited*.

Org mode replaces aword processor, a presentation creator, and a
spreadsheet editor. The spreadsheet ability captures more than 80% use
cases wherein one wishes to include a table in a text document
destined for physical publication. (It is clear that Excel
spreadsheets are /not/ destined for physical publication---simply
attempt to print an Excel spreadsheet with the default settings.)  In
my opinion, Org mode matches all /useful/ features of the Microsoft
Office suite 1-to-1.

What follows are customizations designed to make Org mode behave more
like Microsoft Word. The end goal is, once again, to draw as many new
users to Emacs as possible!

Check out how much information Org mode keeps concerning the most
recent header:

#+NAME: org-meta-info
#+BEGIN_SRC emacs-lisp :tangle no :results pp :exports both :cache yes
  (save-excursion
    (org-previous-visible-heading 1)
    (org-entry-properties))
#+END_SRC

(This block was evaluated on Microsoft Windows.)

#+RESULTS[cf982044956d8f3ec89e7a9da80976b1b19db423]: org-meta-info
: (("CATEGORY" . "smart-documents")
:  ("BLOCKED" . "")
:  ("FILE" . "c:/Users/blend/AppData/Roaming/.emacs.d/smart-documents.org")
:  ("PRIORITY" . "A")
:  ("ITEM" . "Introduction"))

** Basic customization

*** Base folder

Org base directory is in user home on GNU/Linux, or in =AppData= in MS
Windows.

#+NAME: org-directory
#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-directory (concat user-emacs-directory "~/org"))
#+END_SRC

*** Prevent/warn on invisible edits

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-catch-invisible-edits t)
#+END_SRC

** Org cosmetics

First, we ensure the display of markup symbols for *bold*, /italic/,
_underlined_ and +strikethrough+ text, and ensure our document appears
indented upon loading.[fn::It /appears/ indented, but the underlying
plaintext file does not contain tab characters!]

We then set values for many other Org-related cosmetic symbols.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-hide-emphasis-markers nil
        org-startup-indented t
        org-src-preserve-indentation nil
        org-edit-src-content-indentation 2
        org-ellipsis (propertize " ▷ " ; folding symbol
                                 'mouse-face 'highlight
                                 'help-echo "Unfold section."))
#+END_SRC

*** Pretty LaTeX symbols

We display LaTeX entities as UTF8 symbols \rArr this is a slick idea to
further make Emacs look like the exported PDF. Using symbols in tables
is discouraged?

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-pretty-entities t)
#+END_SRC

*** Dynamic numbering of headlines

We enable the dynamic numbering of headlines in an Org buffer. We also
set the numbering face to ~org-special-keyword~, which specifies a
~:background white~ attribute. This is necessary because otherwise,
the background of the numbering may be overridden by the ~TODO~ face
attribute ~:background coral~.

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-hook 'org-mode-hook 'org-num-mode)
  (setq org-num-face 'org-special-keyword)
#+END_SRC

By default, we hide Org document properties such as =#+TITLE=,
=#+AUTHOR=, and =#+DATE=, because those keywords are defined when the
document template is populated. We can nevertheless always access
those properties and edit them manually, with a simple keyboard
shortcut (cf. Section [[Open Org mode document properties]]).

*** Document properties

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun org-property-value (property)
    "Return the value of a given Org document property."
    (interactive)
    (save-excursion
      (goto-char (point-min))
      (re-search-forward
       (concat
        "^[[:space:]]*#\\+"
        property
        ":[[:space:]]*\\(.*?\\)[[:space:]]*$")
       nil t)
      (nth 3 (car (cdr (org-element-at-point))))))
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle no
  (defun sd-document-properties ()
    "Open separate buffer to edit Org mode properties."
    (interactive)
    (let ((title (car (org-property-value "TITLE")))
          (date (org-property-value "DATE")))
      (with-output-to-temp-buffer "Smart Document Properties"
        (print title)
        (print date))))
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-hook 'org-src-mode-hook
            '(lambda ()
               "Disable flycheck for `emacs-lisp-mode'."
               (setq-local flycheck-disabled-checkers
                           '(emacs-lisp-checkdoc))))
#+END_SRC

*** COMMENT Timestamps

# This is a terrible idea :-(

More literary timestamps are exported to LaTeX using the following
custom format:

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-time-stamp-custom-formats
        '("%d %b. %Y (%a)" . "%d %b. %Y (%a), at %H:%M"))
#+END_SRC

*** Sequence of TODOs

#+begin_src emacs-lisp :tangle yes
  (setq org-todo-keywords
        '((sequence "TODO" "|" "DONE")
          (sequence "STUCK" "WAITING" "|" "N/A" "COMPLETED")
          (sequence "CONSTRUCTION" "REVIEWED" "|" "INSTALLED")))

  (setq org-todo-keyword-faces
        '(("STUCK" . (:height 1.6 :background "red" :foreground "white" :weight bold))
          ("WAITING" . (:height 1.6 :background "yellow"))
          ("N/A" . (:height 1.6 :background "LightSteelBlue3" :foreground "white"))
          ("COMPLETED" . (:height 1.6 :background "green" :foreground "white"))))
#+end_src

** Programming a Smart Documents

The following languages can be used inside =SRC= blocks, in view of
being executed by the Org Babel backend upon document export.

#+BEGIN_SRC emacs-lisp :tangle yes
  (org-babel-do-load-languages
   'org-babel-load-languages
   '((shell . t)
     (python . t)
     (ditaa . t)
     (plantuml . t)
     (emacs-lisp . t)
     (awk . t)
     (ledger . t)
     (latex . t)
     (C . t)
     (gnuplot . t)))
#+END_SRC

** Agenda

The agenda displays a chronological list of headings across all agenda
files for which the heading or body contain a matching
=org-time-stamp=.[fn::An =org-time-stamp= can be inserted with ~C-c .~
(period)]

We open the agenda in a separate window.

#+BEGIN_SRC emacs-lisp :tangle no
  (setq org-agenda-window-setup 'other-frame)
#+END_SRC

** LaTeX export

We'll be compiling our documents with LuaTeX. This will afford us some
future-proofing, since it was designated as the successor to pdfTeX by
the latter's creators.

First, we define the command executed when an Org file is exported to
LaTeX. We'll use =latexmk=, the Perl script which automagically runs
binaries related to LaTeX in the correct order and the right amount of
times.

Options and why we need them:
- ~-shell-excape~ :: required by minted to color source blocks
- ~-pdflatex=lualatex~ :: we use lualatex to generate our PDF
- ~-interaction=nonstopmode~ :: go as far as possible without
  prompting user for input

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-latex-pdf-process
        '("latexmk -pdf -f \
  -pdflatex=lualatex -shell-escape \
  -interaction=nonstopmode -outdir=%o %f"))
#+END_SRC

*** Exporting timestamps

We customize the format for org time stamps to make them appear
monospaced in our exported LaTeX documents. This makes them visually
distinguishable from body text.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-latex-active-timestamp-format
        "\\texttt{%s}")
  (setq org-latex-inactive-timestamp-format
        "\\texttt{%s}")
#+END_SRC

*** LaTeX packages

The following packages are loaded for every time we export to LaTeX.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-latex-packages-alist
        '(("AUTO" "babel" t
           ("pdflatex"))
          ("AUTO" "polyglossia" t ; Babel replacement for LuaLaTeX
           ("xelatex" "lualatex"))
          ("" "fontspec" t ; Fonts for LuaLaTeX
           ("lualatex"))
          ("" "booktabs" t ; Publication quality tables
           ("pdflatex" "lualatex"))
          ("" "wasysym" t ; Emojis and other symbols
           ("pdflatex" "lualatex"))
          ("" "lettrine" t
           ("pdflatex" "lualatex"))
          ("table,svgnames" "xcolor" t ; svgnames opens up ~150 new color keywords
           ("pdflatex" "lualatex"))
          ("skip=0.5\\baselineskip" "caption" t ; Increase space between floats and captions
           ("pdflatex" "lualatex"))))
#+END_SRC

*** COMMENT Colored source blocks in PDF export

# Too distracting. Focus on fonts.

Little bonus for GNU/Linux users: syntax highlighting for source code
blocks in LaTeX exports.

#+BEGIN_SRC emacs-lisp :tangle yes
  (when (string-equal system-type "gnu/linux")
    (add-to-list 'org-latex-packages-alist '("AUTO" "minted" t
                                             ("pdflatex" "lualatex")))
    (setq org-latex-listings 'minted)
    (setq org-latex-minted-options '(("style" "friendly")
                                     ("breaklines" "true")
                                     ("breakanywhere" "true"))))
#+END_SRC

*** Cleaning directory after export

Now, we set the files to be deleted when a LaTeX \rightarrow PDF
compilation occurs. We only care about two files, in the end: the Org
mode file for edition, and the PDF for distribution.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-latex-logfiles-extensions
        '("aux" "bcf" "blg" "fdb_latexmk"
          "fls" "figlist" "idx" "log" "nav"
          "out" "ptc" "run.xml" "snm" "toc" "vrb" "xdv"
          "tex" "lot" "lof"))
#+END_SRC

*** Chronological diary entries

By default, Org agenda inserts diary entries as the first under the
selected date. It is preferable to insert entries in the order that
they were recorded, i.e. chronologically.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-agenda-insert-diary-strategy 'date-tree-last)
#+END_SRC

*** Extra LaTeX class

This /letter/ template completes the other default LaTeX classes.

#+BEGIN_SRC emacs-lisp :tangle yes
  (require 'ox-publish)
  (add-to-list 'org-latex-classes
               '("letter"
                 "\\documentclass[11pt]{letter}"
                 ("\\chapter{%s}" . "\\chapter*{%s}")
                 ("\\section{%s}" . "\\section*{%s}")
                 ("\\subsection*{%s}" . "\\subsection*{%s}")
                 ("\\subsubsection*{%s}" . "\\subsubsection*{%s}")))
#+END_SRC

*** Table of contents

By default, body text can immediately follow the table of contents. It
is however cleaner to separate table of contents with the rest of the
work.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq org-latex-toc-command "\\tableofcontents\\clearpage")
#+END_SRC

The following makes =TODO= items appear red and =CLOSED= items appear
green in Org's LaTeX exports. Very stylish, much flair!

*** AUCTEX

#+BEGIN_SRC emacs-lisp :tangle yes
  (use-package tex
    :defer t
    :ensure auctex
    :ensure auctex-latexmk
    :config
    (setq TeX-auto-save t))

  (auctex-latexmk-setup)
#+END_SRC

*** Groff export

#+BEGIN_SRC emacs-lisp :tangle no
  (require 'ox-groff)
#+END_SRC

** TODO Org links

This is a mind-bending capacity of Org mode: we can assign arbitrary
functions to be executed when a user follows an Org link. Org links
appear like hyperlinks both in buffers and PDF exports---e.g. the
following link to this very section, Section [[Org links]]---but their
in-buffer behavior can be arbitrarily assigned.

#+BEGIN_SRC emacs-lisp :tangle no
  (org-add-link-type
   "tag" 'endless/follow-tag-link)

  (defun endless/follow-tag-link (tag)
    "Display a list of TODO headlines with tag TAG.
  With prefix argument, also display headlines without a TODO keyword."
    (org-tags-view (null current-prefix-arg) tag))

  [[tag:work+phonenumber-boss][Optional Description]]
#+END_SRC

* One-click workflows

In this section, we'll implement useful one-click workflows. It comes
later than the keybinding definitions for two reasons:

1. To a new user, keybindings are more relevant than the
   implementation of the bound function---it is more important to know
   how to drive a car than how a car works.
2. If the following subsections share the same name as the keybinding
   subsection (Section [[Keyboard shortcuts]]), the links to that name
   will resolve to the earliest heading in the document, i.e. the
   keybinding subsection and not the subsection describing the
   `one-click workflow'.

** TODO Export to PDF

This series of ~quick-export~ functions have one objective: harmonize
the export of Emacs buffers to PDF. Org mode does this by design; we
describe additional exports for other modes, most notably Nroff mode
and Ledger mode.

*** From Org mode

This reimplements the most common Org mode export: Org \rightarrow LaTeX \rightarrow
PDF. The binding is defined in Section [[Export to PDF]].

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-quick-export--org ()
    "Org mode async export to PDF and open.
       This basically reimplements `C-c C-e C-a l o'."
    (org-open-file (org-latex-export-to-pdf)))
#+END_SRC

*** From a Ledger report

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-quick-export--ledger-report ()
    "Quick export for `ledger-mode' report buffers."
    (let ((old-buffer (current-buffer)))
      (with-output-to-temp-buffer "**SD Export**"
        (print "#+SETUPFILE: ~/.emacs.d/templates/documents/default.org")
        (newline)
        (insert-buffer-substring old-buffer)
        (forward-line 10)
        (org-table-convert-region (point) (goto-char (point-max)))
        (setq more-lines-p t)
        (while more-lines-p
          (move-end-of-line 1)
          (newline)
          (setq more-lines-p (= 0 (forward-line 1))))
        (org-open-file (org-latex-export-to-pdf)))))
#+END_SRC

*** From Nroff mode

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-quick-export--nroff (macros)
    "Export Nroff/Groff buffer to PDF, with specified macro set."
    (let* ((file-exported-name
            (concat (file-name-sans-extension buffer-file-name)
                    (format "-%s.pdf" macros)))
           (command-export
            (format "groff -%s -Tps %s | ps2pdf - > %s"
                    macros
                    (buffer-file-name)
                    file-exported-name)))
      (shell-command command-export)
      (org-open-file file-exported-name)))
#+END_SRC

*** Quick export

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-quick-export ()
    "Quickly prettify and export current buffer to PDF."
    (interactive)
    (cond ((eq major-mode 'org-mode)
           (sd-quick-export--org))
          ((eq major-mode 'nroff-mode)
           (sd-quick-export--nroff
            (read-string "Macro set used (ms, me, mm...): ")))
          ((eq major-mode 'emacs-lisp-mode)
           (message "No quick-export implemented for emacs-lisp-mode yet."))
          ((eq major-mode 'ledger-report-mode)
           (sd-quick-export--ledger-report))
          (t (message (format "No sd-quick-export backend for %s."
                              major-mode)))))
#+END_SRC

** Operate on whole buffer

*** Fix indentation

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-indent-buffer ()
    "Indent entire buffer."
    (interactive)
    (save-excursion
      (indent-region (point-min) (point-max) nil)))
#+END_SRC

*** Beautify

**** All types of buffers

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-beautify-buffer ()
    "Clean up buffer in the most general sense.

  This means performing the following actions:
  1) indenting the buffer according to the major mode in force,
  2) deleting trailing whitespaces.

  As well as a couple other things."
    (interactive)
    (sd-indent-buffer)
    (delete-trailing-whitespace)
    (when (string-equal
           major-mode "org-mode")
      (sd-org-fix-headlines-spacing)))


#+END_SRC

**** COMMENT For Org mode, specifically

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-org-fix-headlines-spacing ()
    "Insert the proper amount of newlines between Org headlines."
    (save-excursion
      (progn
        (goto-char (point-min))
        (mark-whole-buffer)
        (delete-blank-lines)
        (org-next-visible-heading)
        (re-search-backward "^$")))
#+END_SRC

** Smart quitting

***  Window

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-delete-window-or-previous-buffer ()
    "Delete window; if sole window, previous buffer."
    (interactive)
    (if (> (length (window-list)) 1)
        (delete-window)
      (previous-buffer)))
#+END_SRC

*** Frame

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-delete-frame-or-kill-emacs ()
    (interactive)
    "Delete frame; if sole frame, kill Emacs."
    (if (> (length (frame-list)) 1)
        (delete-frame)
      (save-buffers-kill-terminal)))
#+END_SRC

* Editing preferences

These customizations enhance editor usability. They also encompass
cosmetic changes not brought about a specific package.

** Editor

*** Coding standards

This is just a better default. Don't @ me.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq c-default-style "linux"
        c-basic-offset 4)
#+END_SRC

*** Recent files

The keybinding for opening a recently visited file is described in
paragraph [[Open a recently visited file]].

#+BEGIN_SRC emacs-lisp :tangle yes
  (recentf-mode 1)
  (setq recentf-max-menu-items 100)
  (setq recentf-max-saved-items 100)
  (run-at-time nil (* 5 60) 'recentf-save-list)
#+END_SRC

*** Reload changed files silently

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-auto-revert-mode)
#+END_SRC

** Frame

*** Header & mode lines
# Top of the buffer is more intuitive for buffer info, bottom is more
# intuitive for buffer action.

**** TODO Icons
:PROPERTIES:
:sd-unpack-path: sd-icons.el
:END:

We start by defining some icons we wish to include in our user
interface. Emacs allows the usage of GIF images---this paves the way
for UI elements which may be animated.

#+BEGIN_SRC emacs-lisp :tangle yes
  (defcustom sd-icon-loading
    (create-image
     (concat user-emacs-directory "img/icons/ellipsis.gif")
     'gif nil
     :scale 0.4)
    "The GIF representing \"loading\". Not animated by default."
    :type 'sexp
    :version "27.1"
    :group 'sd)

  (defun sd-icon-loading ()
    "Insert an animated blue ellipsis."
    (insert-image sd-icon-loading)
    (image-animate sd-icon-loading 0 t))

#+END_SRC

**** Header line

In Org mode, the document header line will be the title of the
document we are working on currently. We start by defining keybindings
for our header line buttons for navigating through open windows.

#+BEGIN_SRC emacs-lisp :tangle yes
  (defvar sd-header-line-previous-buffer-keymap
    (let ((map (make-sparse-keymap)))
      (define-key map [header-line mouse-1] 'previous-buffer)
      map)
    "Keymap for what is displayed in the header line, with a single
    window.")

  (defvar sd-header-line-kill-buffer-keymap
    (let ((map (make-sparse-keymap)))
      (define-key map [header-line mouse-1] 'kill-buffer-and-window)
      map)
    "Keymap for closing current window.")

  (defvar sd-header-line-maximize-window-keymap
    (let ((map (make-sparse-keymap)))
      (define-key map [header-line mouse-1] 'delete-other-windows)
      map)
    "Keymap for maximizing the current window.")

  (defvar sd-header-line-minimize-window-keymap
    (let ((map (make-sparse-keymap)))
      (define-key map [header-line mouse-1] 'delete-window)
      map)
    "Keymap for minimizing the current window.")
#+END_SRC

Now, we describe the actual format of the header line.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq-default
   header-line-format
   '(:eval
     (list
      (if (eq (length (window-list)) 1)
          (propertize " ↤ "
                      'face 'org-meta-line
                      'mouse-face 'highlight
                      'keymap sd-header-line-previous-buffer-keymap
                      'help-echo "Return to previous window.")
        (list (propertize " ❌ "
                          'face 'org-meta-line
                          'mouse-face 'org-todo
                          'keymap sd-header-line-kill-buffer-keymap
                          'help-echo "Close this window.")
              (propertize " ⇱"
                          'face 'org-meta-line
                          'mouse-face 'highlight
                          'keymap sd-header-line-maximize-window-keymap
                          'help-echo "Maximize this window.")
              (propertize "⇲ "
                          'face 'org-meta-line
                          'mouse-face 'highlight
                          'keymap sd-header-line-minimize-window-keymap
                          'help-echo "Minimize this window.")))
      mode-line-buffer-identification)))

  (image-animate sd-icon-loading 0 t)
#+END_SRC

**** Mode line

This interpretation of the ideal mode line is the result of carefully
studying the default ~mode-line~, as well as studying various
customizations online.

#+BEGIN_SRC emacs-lisp :tangle yes
  (defvar sd-mode-line-lock-buffer-keymap
    (let ((map (make-sparse-keymap)))
      (define-key map [mode-line mouse-1] 'read-only-mode)
      map)
    "Keymap for locking/unlocking the current buffer.")
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq-default
   mode-line-format
   (list
    mode-line-front-space
    '(:eval (if buffer-read-only
                (propertize "🔒"
                            'keymap sd-mode-line-lock-buffer-keymap
                            'help-echo "C-x C-q: unlock buffer.")
              (propertize "🔓"
                          'keymap sd-mode-line-lock-buffer-keymap
                          'help-echo "C-x C-q: lock buffer.")))
    '(:eval (if (buffer-modified-p)
                (propertize " 🖉 "
                            'help-echo "Buffer is modified.")
              (propertize " ✓ "
                          'help-echo "Buffer is saved.")))
    mode-line-modes " "
    mode-line-end-spaces))
#+END_SRC

** Window

** Buffer

*** Save cursor location

Save cursor location in visited buffer after closing it or Emacs.

#+BEGIN_SRC emacs-lisp :tangle yes
  (save-place-mode 1)
#+END_SRC

*** Column filling

We leave the default ~fill-column~ unchanged, so as to minimally
disrupt a user's existing documents.  We automatically break lines
longer than =fill-column=.

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-hook 'org-mode-hook
            'turn-on-auto-fill)
#+END_SRC

** Text

*** Beautiful symbols

We want the Emacs Lisp keyword =lambda= to be rendered as \lambda
within the editor. This is mostly for a subjective ``cool'' factor.

#+BEGIN_SRC emacs-lisp :tangle yes
  (global-prettify-symbols-mode 1)
#+END_SRC

*** Org mode sugar

Let's pimp out the appearance of our text in Org mode. First, we
prettify checkbox lists when viewed on GNU/Linux systems.

#+BEGIN_SRC emacs-lisp :tangle yes
  (when (string-equal system-type "gnu/linux")
    (add-hook 'org-mode-hook
              (lambda ()
                "Beautify Org symbols."
                (push '("[ ]" .  "○") ; Unchecked item
                      prettify-symbols-alist)
                (push '("[X]" . "◉" ) ; Checked item
                      prettify-symbols-alist)
                (push '("[-]" . "◎" ) ; Partially checked item
                      prettify-symbols-alist)
                (push '("-" . "⁃" ) ; DONE headings
                      prettify-symbols-alist)
                (prettify-symbols-mode))))
#+END_SRC

- [ ] This first item is unticked
- [-] This second item is partially completed
  - [X] This first sub-item is ticked
  - [ ] This sub-item is not ticked
- [ ] This third item is ticked

*** Electric modes

Electricity is a very important technology. In Emacs jargon,
``electric'' modes tend to automate behaviors or present some elegant
simplification to a workflow.[fn::More information can be found at
[[https://www.emacswiki.org/emacs/Electricity]].]

#+BEGIN_SRC emacs-lisp :tangle yes
  (electric-pair-mode) ; Certain character pairs are automatically completed.
  (electric-indent-mode) ; Newlines are always intelligently indented.
#+END_SRC

** Minibuffer

We replace the longer ~yes-or-no-p~ questions with more convenient
~y-or-n-p~.

#+BEGIN_SRC emacs-lisp :tangle yes
  (defalias 'yes-or-no-p 'y-or-n-p)
#+END_SRC

Disable minibuffer scroll bar.

#+BEGIN_SRC emacs-lisp :tangle yes
  (set-window-scroll-bars (minibuffer-window) nil nil)
#+END_SRC

* Themes
# This is just another comment.
Without a carefully designed theme, our editor would become
unusable. Thus, we /describe/ two themes that were developed
*purposefully* and iteratively.

#+BEGIN_SRC emacs-lisp :tangle yes
  (setq custom-theme-directory (concat user-emacs-directory "themes/"))
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle no
  (load-theme 'sd-compagnon-dark)
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle no
  (load-theme 'molokai)
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle yes
  (load-theme 'sd-light)
#+END_SRC

#+BEGIN_SRC emacs-lisp :tangle no
  (load-theme 'sd-dark)
#+END_SRC

** My light and dark themes

A highly legible, unambiguous, and classic theme.

*** Colors

The default face is a black foreground on a white background, this
matches MS Word. We are striving for a simple, intuitive color scheme.

Most of the [[https://www.interaction-design.org/literature/topics/affordances][affordance]] cues derived from color are identical in
both light and dark themes (Table [[theme-color-1]]).

#+NAME: theme-color-1
#+CAPTION[Light and dark themes' colors]: Light and dark themes' colors.
#+ATTR_LATEX: :booktabs t
| Color                           | ~sd-light~                      | ~sd-dark~          |
|---------------------------------+---------------------------------+--------------------|
| Black                           | default text                    | default background |
| \_ Lighter shades               | lesser headers                  | /n/a/              |
| White                           | default background              | default text       |
| \_ Darker shades                | /n/a/                           | lesser headers     |
| \color{Red} Red                 | negative                        | /same/             |
| \color{Tomato} Tomato           | timestamp `TODO'                | /same/             |
| \color{Green} Green             | positive                        | /same/             |
| \color{ForestGreen} ForestGreen | timestamp `DONE'                | /same/             |
| \color{Blue} Blue               | interactive content; links      | /same/             |
| \color{SteelBlue} SteelBlue     | anything Org mode; anchor color | /same/             |
| \color{DeepSkyBlue} DeepSkyBlue | ~highlight~                     | /same/             |
| \color{DodgerBlue} DodgerBlue   | ~isearch~                       | /same/             |
| \color{Purple} Purple           | Code syntax highlighting        | /same/             |

**** Red

**** Green

**** Blue

**** Purple

Purple is Emacs' main logo color. Since we use Emacs for coding a lot,
code syntax highlighting to could be in the pink/purple shades.

*** Cursors

In order to imitate other modern text editors, we resort to a blinking
bar cursor. We choose red, the most captivating color, because the
cursor is arguably the region on our screen:

1. most often looked at;
2. most often searched when lost.

In files containing only ~fixed-pitch~ fonts (i.e. files containing
only code), the cursor becomes a high-visibility box.

In files containing a mix of ~variable-pitch~ and ~fixed-pitch~ fonts,
the cursor is a more MS Word-like bar.

#+BEGIN_SRC emacs-lisp :tangle no
  (setq-default cursor-type 'box)
#+END_SRC

*** TODO Fonts

Here are some fonts I discovered and enjoyed since I began learning
Emacs.

**** Serif

- Crimson Pro[fn::] :: ~variable-pitch~,
  default body text font
  - Inspired by Garamond
- Linux Libertine[fn::] :: ~variable-pitch~,
  default body text font
  - Inspired by Garamond

**** Sans serif

- Public Sans[fn::https://public-sans.digital.gov/] :: ~variable-pitch~,
  default body text font
  - Very modern yet neutral
  - Designed for the U.S. government
  - Exceptional color on screen
- Jost[fn::https://indestructibletype.com/Jost.html] :: ~org-document-title~
  and ~org-level-1~
  - Ultra-modern
  - Tasteful amount of geometric inspiration
- Open Sans[fn::https://www.opensans.com/] :: ~variable-pitch~
  - Ooh geometric Bauhaus influences, look at me
  - Tall leading height is =harmonious=
- Liberation Sans[fn::https://en.wikipedia.org/wiki/Liberation_fonts] :: +~variable-pitch~+
  - Metrically compatible with /Arial/ (ugh)
  - Unoffensive, unambitious forms
  - Pretty angular letters, it's like you're trying to read squares

**** Monospace

- Hack[fn::https://sourcefoundry.org/hack/] :: ~default~ and
  ~fixed-pitch~, default code font
  - Legible, modern monospace font
  - Strict, sharp, uncompromising
- Hermit[fn::https://pcaro.es/p/hermit/] :: ~org-block~, anything
  Org/meta in general
  - Slightly wider than Hack
  - More opinionated shapes
  - Very legible parentheses, very useful for Emacs Lisp!
- Courier Prime[fn::https://quoteunquoteapps.com/courierprime/index.php]  :: monospace
  in print

**** Using proportional fonts when needed

We use ~variable-pitch-mode~ for appropriate modes.

#+BEGIN_SRC emacs-lisp :tangle yes
  (add-hook 'org-mode-hook 'variable-pitch-mode)
  (add-hook 'info-mode-hook 'variable-pitch-mode)
#+END_SRC

**** TODO Default font size

Make default font size larger on displays of which the resolution
is greater than 1920\times1080.

#+BEGIN_SRC emacs-lisp :tangle no
  (if (< screen-width 1920)
      (default-font)
    else)
#+END_SRC

** TODO /Wealthy/ document theme

#+NAME: claude-garamont
#+CAPTION[Claude Garamont, an icon of font design]: Claude Garamont, an icon of font design. World-renowned for his elegant typefaces, which inspired many generations of typographers.
#+ATTR_LATEX: :width 0.2\pagewidth
[[~/.emacs.d/img/smart-documents/ClaudeGaramond.jpeg]]

#+LATEX: \garamond
\lettrine{G}{ood} golly, nobody wishes for a /pedestrian/ theme!  Let
your entourage know that you're rocking an editor fit for a king with
this finely crafted `wealthy' theme. Selecting it shall enable the
following fancitudes:

1. The default font shall be sublimed in the form of /EB Garamond/
2. Bullets will be tastefully replaced with pointing fingers
3. Heading stars will be replaced with Black Queen chess pieces

#+BEGIN_QUOTE
\lettrine{C}{laude} Garamont (c. 1510--1561), known commonly as
*Claude Garamond*, was a French type designer, publisher and
punch-cutter based in Paris. Garamond worked as an engraver of
punches, the masters used to stamp matrices, the moulds used to cast
metal type. He worked in the tradition now called old-style serif
design, which produced letters with a relatively organic structure
resembling handwriting with a pen but with a slightly more structured
and upright design. Considered one of the leading type designers of
all time, he is recognised to this day for the elegance of his
typefaces. Many old-style serif typefaces are collectively known as
Garamond, named after the designer.

From [[https://en.wikipedia.org/wiki/Claude_Garamond]]
#+END_QUOTE

#+LATEX: \publicsans

*** Symbol substitution

#+BEGIN_SRC emacs-lisp :tangle yes
  (defun sd-wealthy ()
    "Beautify symbols for our wealthy theme."
    (push '("-" . "☞" ) prettify-symbols-alist) ; unnumbered bullets
    (push '("*" . "♛" ) prettify-symbols-alist) ; headings
    (prettify-symbols-mode))
#+END_SRC

** TODO ~minimal~

* Late setup

At this point, our editor is almost ready to run. Phew! All that's
left to do is to interrupt our profiling activities, and smartly store
the result of our profiling.

** Profiling---stop

#+BEGIN_SRC emacs-lisp :tangle no
  (profiler-stop)
#+END_SRC

** Profiling---report

#+BEGIN_SRC emacs-lisp :tangle no
  (profiler-report)
#+END_SRC

* Conclusion

In this configuration file, we described a series of customization
steps taken to make Emacs more palatable to modern word processors
users.