nixos-config/dotfiles/emacs/config.org

#+TITLE: EMACS Configuration.
#+AUTHOR: Ayham Mamoun
#+EMAIL: ayhamaboualfadl@gmail.com
#+OPTIONS: toc:nil num:nil

* Configure =use-package=

Always compile the packages, and use the newest version available.

#+BEGIN_SRC emacs-lisp
  (require 'use-package-ensure)
  (setq use-package-always-ensure t)
#+END_SRC

Workaround for a bug in EMACS 26. Where there is an issue installing some packages.

#+BEGIN_SRC emacs-lisp
  (setq gnutls-algorithm-priority "NORMAL:-VERS-TLS1.3")
#+END_SRC

* Load Scripts

Load the typing-speed script.

#+BEGIN_SRC emacs-lisp
  (load-file (concat user-emacs-directory "scripts/typing_speed.el"))
#+END_SRC
  
* UI Prefrences
** Tweak EMACS' window

Disable menu, scrollbar and minibuffer scrollbar.

#+BEGIN_SRC emacs-lisp
  (tool-bar-mode -1)
  (menu-bar-mode -1)
  (scroll-bar-mode -1)
  (set-window-scroll-bars (minibuffer-window) nil nil)
#+END_SRC

Bind frame title to the name of the current project.

#+BEGIN_SRC emacs-lisp
(setq frame-title-format '((:eval (projectile-project-name))))
#+END_SRC

** Load theme

Use 'monokai' theme.

#+BEGIN_SRC emacs-lisp
  (defun apply-theme ()
	"Make frames just slightly transparent."
	(interactive)
  (load-theme 'monokai t))

  (use-package monokai-theme
	:config
	(apply-theme))
  (setq ;; foreground and background
		monokai-foreground     "#ABB2BF"
		monokai-background     "#282C34"
		;; highlights and comments
		monokai-comments       "#F8F8F0"
		monokai-emphasis       "#282C34"
		monokai-highlight      "#FFB269"
		monokai-highlight-alt  "#1B1D1E"
		monokai-highlight-line "#1B1D1E"
		monokai-line-number    "#F8F8F0"
		;; colours
		monokai-blue           "#61AFEF"
		monokai-cyan           "#56B6C2"
		monokai-green          "#98C379"
		monokai-gray           "#3E4451"
		monokai-violet         "#C678DD"
		monokai-red            "#E06C75"
		monokai-orange         "#D19A66"
		monokai-yellow         "#E5C07B")
  (setq monokai-height-minus-1 0.8
		monokai-height-plus-1 1.1
		monokai-height-plus-2 1.15
		monokai-height-plus-3 1.2
		monokai-height-plus-4 1.3)
#+END_SRC

** Configure packages that modify the look
*** =powerline=

Install and use EMACS' =powerline=

#+BEGIN_SRC emacs-lisp
(use-package powerline)
(powerline-default-theme)
#+END_SRC

** Environment specific configuration
*** =ORG-mode= Environment

Replace =ORG-mode= ellipsis with a downward arrow.

#+BEGIN_SRC emacs-lisp
(setq org-ellipsis "↲")
#+END_SRC

* Basic Configuration

Increase the garbage collector threshold, to speed up some operations.

#+BEGIN_SRC emacs-lisp
  (setq gc-cons-threshold 20000000)
#+END_SRC

Treat CamelCaseSubWords as seperate words. 
Note: Check if this suits me.

#+BEGIN_SRC emacs-lisp
  (add-hook 'prog-mode-hook 'subword-mode)
#+END_SRC

If a file starts with #!, make it executable.

#+BEGIN_SRC emacs-lisp
  (add-hook 'after-save-hook 'executable-make-buffer-file-executable-if-script-p)
#+END_SRC

If saving a file in a directory doesn't exist, offer to create the parent directories recursively.

#+BEGIN_SRC emacs-lisp
  (add-hook 'before-save-hook
			(lambda ()
			  (when buffer-file-name
				(let ((dir (file-name-directory buffer-file-name)))
				  (when (and (not (file-exists-p dir)) y-or-n-p (format "Directory %s does not exist, Create it?" dir))
					(make-directory dir t ))))))
#+END_SRC

Require having a new line.

#+BEGIN_SRC emacs-lisp
  (setq require-final-newline t)
#+END_SRC

Make file sizes human-readable to dired buffers.

#+BEGIN_SRC emacs-lisp
  (setq-default dired-listing-switches "-alh")
#+END_SRC

Refresh buffer when the file is changed, stoping buffers and file getting out of sync.

#+BEGIN_SRC emacs-lisp
(global-auto-revert-mode t)
#+END_SRC

When pressing the middle mouse button, paste where the curser is rather than where the mouse is.

#+BEGIN_SRC emacs-lisp
(setq mouse-yank-at-point 1)
#+END_SRC

Better increase and decrease text scale.

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

Enable visual parantheses matching.

#+BEGIN_SRC emacs-lisp
(show-paren-mode 1)
#+END_SRC

Enable Line numberings.

#+BEGIN_SRC emacs-lisp
(global-display-line-numbers-mode)
#+END_SRC

Store backups and temperory files in =temporary-file-directory=.
=/tmp= on Unix. Warning: =/tmp= on most Unix-like systems is VOLATILE, IN-MEMORY storage.

#+BEGIN_SRC emacs-lisp
(setq backup-directory-alist `((".*" . ,temporary-file-directory)))
(setq auto-save-file-name-transforms `((".*", temporary-file-directory t)))
#+END_SRC

* Packages Configuration
** =ag=

Set up =ag= on startup.

#+BEGIN_SRC emacs-lisp
  (use-package ag)
#+END_SRC

** =company=

Enable =company-mode= everywhere.

#+BEGIN_SRC emacs-lisp
  (use-package company)
  (add-hook 'after-init-hook 'global-company-mode)
#+END_SRC

Use =M-/= for completion.

#+BEGIN_SRC emacs-lisp
  (global-set-key (kbd "M-/") 'company-complete-common)
#+END_SRC

** =flycheck=

Install flycheck.

#+BEGIN_SRC emacs-lisp
  (use-package flycheck)
#+END_SRC

** =magit=

Use magit for git repos managment.

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

** =projectile=

Use projectile for useful funcationality for project management.

#+BEGIN_SRC emacs-lisp
  (use-package projectile)
#+END_SRC

** =undo-tree=

Use =undo-tree=.

#+BEGIN_SRC emacs-lisp
  (use-package undo-tree)
#+END_SRC

** Environment Specific Packages.
*** =Lisp= Environment

Use =paredit=.

#+BEGIN_SRC emacs-lisp
  (use-package paredit)
#+END_SRC

Use =rainbow-delimiters=.

#+BEGIN_SRC emacs-lisp
  (use-package rainbow-delimiters)
#+END_SRC

* Programming Environments Configuration

Use 4-spaced characters for tabs by default.

#+BEGIN_SRC emacs-lisp
  (setq-default tab-width 4)
#+END_SRC

Use subword mode.

#+BEGIN_SRC emacs-lisp
  (use-package subword
	:config (global-subword-mode 1))
#+END_SRC

** =C/C++= Environment

Set the tab width when using C/C++ mode.

#+BEGIN_SRC emacs-lisp
  (setq-default c-basic-offset 4)
#+END_SRC

** =Lisp= Environment

Uses lisp packages when lisp languages are enabled.

#+BEGIN_SRC emacs-lisp
  (setq lispy-mode-hooks
		'(emacs-lisp-hook lisp-mode-hook))

  (dolist (hook lispy-mode-hooks)
	(add-hook hook (lambda()
					 (setq show-paren-style 'expression)
  (paredit-mode)
  (rainbow-delimeters-mode))))
#+END_SRC

Set tab with

** =ORG-mode= Environment
This might not be a programming environment, but making a seperate section is an overkill.

Enable indentation in =org= source blocks.

#+BEGIN_SRC emacs-lisp
  (setq org-src-tab-acts-natively t)
#+END_SRC

** =sh= Environment

Indent with 4 spaces.

#+BEGIN_SRC emacs-lisp
  (add-hook 'sh-mode-hook
			(lambda ()
			  (setq sh-basic-offset 4
					sh-indentation 4)))
#+END_SRC
* Misc Configuration

Install =speed-type= for typing practice.

#+BEGIN_SRC emacs-lisp
  (use-package speed-type)
#+END_SRC