;;; prelude-editor.el --- Emacs Prelude: enhanced core editing experience.
;;
;; Copyright © 2011-2013 Bozhidar Batsov
;;
;; Author: Bozhidar Batsov <bozhidar@batsov.com>
;; URL: https://github.com/bbatsov/prelude
;; Version: 1.0.0
;; Keywords: convenience

;; This file is not part of GNU Emacs.

;;; Commentary:

;; Refinements of the core editing experience in Emacs.

;;; License:

;; 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 GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Code:

;; customize
(defgroup prelude nil
  "Emacs Prelude configuration."
  :prefix "prelude-"
  :group 'convenience)

(defcustom prelude-auto-save t
  "Non-nil values enable Prelude's auto save."
  :type 'boolean
  :group 'prelude)

(defcustom prelude-guru t
  "Non-nil values enable guru-mode."
  :type 'boolean
  :group 'prelude)

(defcustom prelude-whitespace t
  "Non-nil values enable Prelude's whitespace visualization."
  :type 'boolean
  :group 'prelude)

(defcustom prelude-clean-whitespace-on-save t
  "Cleanup whitespace from file before it's saved.
Will only occur if prelude-whitespace is also enabled."
  :type 'boolean
  :group 'prelude)

(defcustom prelude-flyspell t
  "Non-nil values enable Prelude's flyspell support."
  :type 'boolean
  :group 'prelude)

;; Death to the tabs!  However, tabs historically indent to the next
;; 8-character offset; specifying anything else will cause *mass*
;; confusion, as it will change the appearance of every existing file.
;; In some cases (python), even worse -- it will change the semantics
;; (meaning) of the program.
;;
;; Emacs modes typically provide a standard means to change the
;; indentation width -- eg. c-basic-offset: use that to adjust your
;; personal indentation width, while maintaining the style (and
;; meaning) of any files you load.
(setq-default indent-tabs-mode nil)   ;; don't use tabs to indent
(setq-default tab-width 8)            ;; but maintain correct appearance

;; delete the selection with a keypress
(delete-selection-mode t)

;; store all backup and autosave files in the tmp dir
(setq backup-directory-alist
      `((".*" . ,temporary-file-directory)))
(setq auto-save-file-name-transforms
      `((".*" ,temporary-file-directory t)))

;; revert buffers automatically when underlying files are changed externally
(global-auto-revert-mode t)

;; hippie expand is dabbrev expand on steroids
(setq hippie-expand-try-functions-list '(try-expand-dabbrev
                                         try-expand-dabbrev-all-buffers
                                         try-expand-dabbrev-from-kill
                                         try-complete-file-name-partially
                                         try-complete-file-name
                                         try-expand-all-abbrevs
                                         try-expand-list
                                         try-expand-line
                                         try-complete-lisp-symbol-partially
                                         try-complete-lisp-symbol))

;; smart tab behavior - indent or complete
(setq tab-always-indent 'complete)

;; smart pairing for all
(require 'smartparens-config)
(setq sp-base-key-bindings 'paredit)
(setq sp-autoskip-closing-pair 'always)
(setq sp-hybrid-kill-entire-symbol nil)
(sp-use-paredit-bindings)

(show-smartparens-global-mode +1)

(define-key prog-mode-map (kbd "M-(") (prelude-wrap-with "("))
;; FIXME: pick terminal friendly binding
;; (define-key prog-mode-map (kbd "M-[") (prelude-wrap-with "["))
(define-key prog-mode-map (kbd "M-\"") (prelude-wrap-with "\""))

;; disable annoying blink-matching-paren
(setq blink-matching-paren nil)

;; diminish keeps the modeline tidy
(require 'diminish)

;; meaningful names for buffers with the same name
(require 'uniquify)
(setq uniquify-buffer-name-style 'forward)
(setq uniquify-separator "/")
(setq uniquify-after-kill-buffer-p t)    ; rename after killing uniquified
(setq uniquify-ignore-buffers-re "^\\*") ; don't muck with special buffers

;; saveplace remembers your location in a file when saving files
(require 'saveplace)
(setq save-place-file (expand-file-name "saveplace" prelude-savefile-dir))
;; activate it for all buffers
(setq-default save-place t)

;; savehist keeps track of some history
(require 'savehist)
(setq savehist-additional-variables
      ;; search entries
      '(search ring regexp-search-ring)
      ;; save every minute
      savehist-autosave-interval 60
      ;; keep the home clean
      savehist-file (expand-file-name "savehist" prelude-savefile-dir))
(savehist-mode +1)

;; save recent files
(require 'recentf)
(setq recentf-save-file (expand-file-name "recentf" prelude-savefile-dir)
      recentf-max-saved-items 500
      recentf-max-menu-items 15)

(defun prelude-recentf-exclude-p (file)
  "A predicate to decide whether to exclude FILE from recentf."
  (let ((file-dir (file-truename (file-name-directory file))))
    (-any-p (lambda (dir)
              (string-prefix-p dir file-dir))
            (mapcar 'file-truename (list prelude-savefile-dir package-user-dir)))))

(add-to-list 'recentf-exclude 'prelude-recentf-exclude-p)
(recentf-mode +1)

;; use shift + arrow keys to switch between visible buffers
(require 'windmove)
(windmove-default-keybindings)

;; automatically save buffers associated with files on buffer switch
;; and on windows switch
(defun prelude-auto-save-command ()
  "Save the current buffer if `prelude-auto-save' is not nil."
  (when (and prelude-auto-save
             buffer-file-name
             (buffer-modified-p (current-buffer))
             (file-writable-p buffer-file-name))
    (save-buffer)))

(defmacro advise-commands (advice-name commands &rest body)
  "Apply advice named ADVICE-NAME to multiple COMMANDS.

The body of the advice is in BODY."
  `(progn
     ,@(mapcar (lambda (command)
                 `(defadvice ,command (before ,(intern (concat (symbol-name command) "-" advice-name)) activate)
                    ,@body))
               commands)))

;; advise all window switching functions
(advise-commands "auto-save"
                 (switch-to-buffer other-window windmove-up windmove-down windmove-left windmove-right)
                 (prelude-auto-save-command))

(add-hook 'mouse-leave-buffer-hook 'prelude-auto-save-command)

;; Autosave buffers when focus is lost
(defun prelude-save-all-buffers ()
  "Save all modified buffers, without prompts."
  (save-some-buffers 'dont-ask))

(when (version<= "24.4" emacs-version)
  (add-hook 'focus-out-hook 'prelude-save-all-buffers))

;; highlight the current line
(global-hl-line-mode +1)

(require 'volatile-highlights)
(volatile-highlights-mode t)
(diminish 'volatile-highlights-mode)

;; tramp, for sudo access
(require 'tramp)
;; keep in mind known issues with zsh - see emacs wiki
(setq tramp-default-method "ssh")

(set-default 'imenu-auto-rescan t)

;; flyspell-mode does spell-checking on the fly as you type
(require 'flyspell)
(setq ispell-program-name "aspell" ; use aspell instead of ispell
      ispell-extra-args '("--sug-mode=ultra"))

(defun prelude-enable-flyspell ()
  "Enable command `flyspell-mode' if `prelude-flyspell' is not nil."
  (when (and prelude-flyspell (executable-find ispell-program-name))
    (flyspell-mode +1)))

(defun prelude-cleanup-maybe ()
  "Invoke `whitespace-cleanup' if `prelude-clean-whitespace-on-save' is not nil."
  (when prelude-clean-whitespace-on-save
    (whitespace-cleanup)))

(defun prelude-enable-whitespace ()
  "Enable `whitespace-mode' if `prelude-whitespace' is not nil."
  (when prelude-whitespace
    ;; keep the whitespace decent all the time (in this buffer)
    (add-hook 'before-save-hook 'prelude-cleanup-maybe nil t)
    (whitespace-mode +1)))

(add-hook 'text-mode-hook 'prelude-enable-flyspell)
(add-hook 'text-mode-hook 'prelude-enable-whitespace)

;; enable narrowing commands
(put 'narrow-to-region 'disabled nil)
(put 'narrow-to-page 'disabled nil)
(put 'narrow-to-defun 'disabled nil)

;; enabled change region case commands
(put 'upcase-region 'disabled nil)
(put 'downcase-region 'disabled nil)

;; enable erase-buffer command
(put 'erase-buffer 'disabled nil)

(require 'expand-region)

;; bookmarks
(require 'bookmark)
(setq bookmark-default-file (expand-file-name "bookmarks" prelude-savefile-dir)
      bookmark-save-flag 1)

;; projectile is a project management mode
(require 'projectile)
(setq projectile-cache-file (expand-file-name  "projectile.cache" prelude-savefile-dir))
(projectile-global-mode t)

;; anzu-mode enhances isearch by showing total matches and current match position
(require 'anzu)
(diminish 'anzu-mode)
(global-anzu-mode)

;; shorter aliases for ack-and-a-half commands
(defalias 'ack 'ack-and-a-half)
(defalias 'ack-same 'ack-and-a-half-same)
(defalias 'ack-find-file 'ack-and-a-half-find-file)
(defalias 'ack-find-file-same 'ack-and-a-half-find-file-same)

;; dired - reuse current buffer by pressing 'a'
(put 'dired-find-alternate-file 'disabled nil)

;; always delete and copy recursively
(setq dired-recursive-deletes 'always)
(setq dired-recursive-copies 'always)

;; if there is a dired buffer displayed in the next window, use its
;; current subdir, instead of the current subdir of this dired buffer
(setq dired-dwim-target t)

;; enable some really cool extensions like C-x C-j(dired-jump)
(require 'dired-x)

;; ediff - don't start another frame
(require 'ediff)
(setq ediff-window-setup-function 'ediff-setup-windows-plain)

;; clean up obsolete buffers automatically
(require 'midnight)

;; smarter kill-ring navigation
(require 'browse-kill-ring)
(browse-kill-ring-default-keybindings)
(global-set-key (kbd "s-y") 'browse-kill-ring)

;; automatically indenting yanked text if in programming-modes
(defvar yank-indent-modes
  '(LaTeX-mode TeX-mode)
  "Modes in which to indent regions that are yanked (or yank-popped).
Only modes that don't derive from `prog-mode' should be listed here.")

(defvar yank-indent-blacklisted-modes
  '(python-mode slim-mode haml-mode)
  "Modes for which auto-indenting is suppressed.")

(defvar yank-advised-indent-threshold 1000
  "Threshold (# chars) over which indentation does not automatically occur.")

(defun yank-advised-indent-function (beg end)
  "Do indentation, as long as the region isn't too large."
  (if (<= (- end beg) yank-advised-indent-threshold)
      (indent-region beg end nil)))

(defadvice yank (after yank-indent activate)
  "If current mode is one of 'yank-indent-modes,
indent yanked text (with prefix arg don't indent)."
  (if (and (not (ad-get-arg 0))
           (not (member major-mode yank-indent-blacklisted-modes))
           (or (derived-mode-p 'prog-mode)
               (member major-mode yank-indent-modes)))
      (let ((transient-mark-mode nil))
    (yank-advised-indent-function (region-beginning) (region-end)))))

(defadvice yank-pop (after yank-pop-indent activate)
  "If current mode is one of `yank-indent-modes',
indent yanked text (with prefix arg don't indent)."
  (when (and (not (ad-get-arg 0))
             (not (member major-mode yank-indent-blacklisted-modes))
             (or (derived-mode-p 'prog-mode)
                 (member major-mode yank-indent-modes)))
    (let ((transient-mark-mode nil))
      (yank-advised-indent-function (region-beginning) (region-end)))))

;; abbrev config
(add-hook 'text-mode-hook 'abbrev-mode)

;; make a shell script executable automatically on save
(add-hook 'after-save-hook
          'executable-make-buffer-file-executable-if-script-p)

;; .zsh file is shell script too
(add-to-list 'auto-mode-alist '("\\.zsh\\'" . shell-script-mode))

;; whitespace-mode config
(require 'whitespace)
(setq whitespace-line-column 80) ;; limit line length
(setq whitespace-style '(face tabs empty trailing lines-tail))

;; saner regex syntax
(require 're-builder)
(setq reb-re-syntax 'string)

(require 'eshell)
(setq eshell-directory-name (expand-file-name "eshell" prelude-savefile-dir))

(setq semanticdb-default-save-directory
      (expand-file-name "semanticdb" prelude-savefile-dir))

;; Compilation from Emacs
(defun prelude-colorize-compilation-buffer ()
  "Colorize a compilation mode buffer."
  (interactive)
  ;; we don't want to mess with child modes such as grep-mode, ack, ag, etc
  (when (eq major-mode 'compilation-mode)
    (let ((inhibit-read-only t))
      (ansi-color-apply-on-region (point-min) (point-max)))))

(require 'compile)
(setq compilation-ask-about-save nil  ; Just save before compiling
      compilation-always-kill t       ; Just kill old compile processes before
                                      ; starting the new one
      compilation-scroll-output 'first-error ; Automatically scroll to first
                                             ; error
      )

;; Colorize output of Compilation Mode, see
;; http://stackoverflow.com/a/3072831/355252
(require 'ansi-color)
(add-hook 'compilation-filter-hook #'prelude-colorize-compilation-buffer)

;; enable Prelude's keybindings
(prelude-global-mode t)

;; sensible undo
(global-undo-tree-mode)
(diminish 'undo-tree-mode)

;; enable winner-mode to manage window configurations
(winner-mode +1)

;; diff-hl
(global-diff-hl-mode +1)
(add-hook 'dired-mode-hook 'diff-hl-dired-mode)

;; easy-kill
(global-set-key [remap kill-ring-save] 'easy-kill)
(global-set-key [remap mark-sexp] 'easy-mark)

(provide 'prelude-editor)

;;; prelude-editor.el ends here