;;; feature/evil/config.el

;; I'm a vimmer at heart. Its modal philosophy suits me better, and this module
;; strives to make Emacs a much better vim than vim was.

(def-setting! :evil-state (&rest mode-state-list)
  "Set the initialize STATE of MODE using `evil-set-initial-state'."
  (if (cl-every #'listp mode-state-list)
      `(progn
         ,@(let (forms)
             (dolist (it mode-state-list (nreverse forms))
               (unless (consp it)
                 (error ":evil-state expected cons cells, got %s" it))
               (push `(evil-set-initial-state ',(car it) ',(cdr it)) forms))))
    (let ((argc (length mode-state-list)))
      (unless (= argc 2)
        (error ":evil-state expected 2 arguments, got %s" argc)))
    `(evil-set-initial-state ',(car mode-state-list) ',(cadr mode-state-list))))


;;
;; evil-mode
;;

(def-package! evil :demand t
  :init
  (setq evil-want-C-u-scroll t
        evil-want-visual-char-semi-exclusive t
        evil-want-fine-undo nil
        evil-want-Y-yank-to-eol t
        evil-magic t
        evil-echo-state t
        evil-indent-convert-tabs t
        evil-ex-search-vim-style-regexp t
        evil-ex-substitute-global t
        evil-ex-visual-char-range t  ; column range for ex commands
        evil-insert-skip-empty-lines t

        ;; don't activate mark on shift-click
        shift-select-mode nil)

  :config
  (evil-mode +1)
  (evil-select-search-module 'evil-search-module 'evil-search)

  (set! :popup
    '("*evil-registers*" :size 0.3)
    '("*Command Line*" :size 8))

  ;; Set cursor colors later, presumably once theme is loaded
  (defun +evil*init-cursors (&rest _)
    (setq evil-default-cursor (face-attribute 'cursor :background nil t)
          evil-normal-state-cursor 'box
          evil-emacs-state-cursor  `(,(face-attribute 'warning :foreground nil nil) box)
          evil-insert-state-cursor 'bar
          evil-visual-state-cursor 'hollow))
  (advice-add #'load-theme :after #'+evil*init-cursors)

  ;; highlight matching delimiters where it's important
  (defun +evil|show-paren-mode-off () (show-paren-mode -1))
  (add-hook 'evil-insert-state-entry-hook   #'show-paren-mode)
  (add-hook 'evil-insert-state-exit-hook    #'+evil|show-paren-mode-off)
  (add-hook 'evil-visual-state-entry-hook   #'show-paren-mode)
  (add-hook 'evil-visual-state-exit-hook    #'+evil|show-paren-mode-off)
  (add-hook 'evil-operator-state-entry-hook #'show-paren-mode)
  (add-hook 'evil-operator-state-exit-hook  #'+evil|show-paren-mode-off)
  (add-hook 'evil-normal-state-entry-hook   #'+evil|show-paren-mode-off)

  (dolist (mode '(tabulated-list-mode view-mode comint-mode term-mode calendar-mode Man-mode grep-mode))
    (evil-set-initial-state mode 'emacs))

  ;; make `try-expand-dabbrev' from `hippie-expand' work in mini-buffer
  ;; @see `he-dabbrev-beg', so we need re-define syntax for '/'
  (defun minibuffer-inactive-mode-hook-setup ()
    (set-syntax-table (let* ((table (make-syntax-table)))
                        (modify-syntax-entry ?/ "." table)
                        table)))
  (add-hook 'minibuffer-inactive-mode-hook #'minibuffer-inactive-mode-hook-setup))

(defsubst +evil--textobj (key inner-fn &optional outer-fn)
  "Define a text object."
  (define-key evil-inner-text-objects-map key inner-fn)
  (define-key evil-outer-text-objects-map key (or outer-fn inner-fn)))


;;
;; evil hacks
;;

(defun +evil*esc ()
  "Disable search highlights and quit the minibuffer if open."
  (when (minibuffer-window-active-p (minibuffer-window))
    (abort-recursive-edit))
  (when (evil-ex-hl-active-p 'evil-ex-search)
    (evil-ex-nohighlight)))
(advice-add #'evil-force-normal-state :after #'+evil*esc)

(defun +evil*static-reindent (orig-fn &rest args)
  "Don't move cursor on indent."
  (save-excursion (apply orig-fn args)))
(advice-add #'evil-indent :around #'+evil*static-reindent)

;; Move to new split
(defun +evil*window-follow (&rest _)  (evil-window-down 1))
(defun +evil*window-vfollow (&rest _) (evil-window-right 1))
(advice-add #'evil-window-split  :after #'+evil*window-follow)
(advice-add #'evil-window-vsplit :after #'+evil*window-vfollow)

;; monkey patch `evil-ex-replace-special-filenames' to add more ex
;; substitution flags to evil-mode
(advice-add #'evil-ex-replace-special-filenames
            :override #'+evil*ex-replace-special-filenames)

;; Add extra argument types that highlight matches in the current buffer.
;; TODO Must be simpler way to do this
(evil-ex-define-argument-type buffer-match :runner +evil-ex-buffer-match)
(evil-ex-define-argument-type global-match :runner +evil-ex-global-match)

(evil-define-interactive-code "<//>"
  :ex-arg buffer-match (list (when (evil-ex-p) evil-ex-argument)))
(evil-define-interactive-code "<g//>"
  :ex-arg global-match (when (evil-ex-p) (evil-ex-parse-global evil-ex-argument)))

(evil-define-operator +evil:global (beg end pattern command &optional invert)
  "Rewritten :g[lobal] that will highlight buffer matches. Takes the same arguments."
  :motion mark-whole-buffer :move-point nil
  (interactive "<r><g//><!>")
  (evil-ex-global beg end pattern command invert))

(evil-define-operator +evil:align (&optional beg end bang pattern)
  "Ex interface to `align-regexp'. Accepts vim-style regexps."
  (interactive "<r><!><//>")
  (align-regexp
   beg end
   (concat "\\(\\s-*\\)"
           (if bang
               (regexp-quote pattern)
             (evil-transform-vim-style-regexp pattern)))
   1 1))

(evil-ex-define-cmd "g[lobal]" #'+evil:global)
(evil-ex-define-cmd "al[ign]"  #'+evil:align)


;;
;; Plugins
;;

(def-package! evil-args
  :commands (evil-inner-arg evil-outer-arg
             evil-forward-arg evil-backward-arg
             evil-jump-out-args)
  :init (+evil--textobj "a" #'evil-inner-arg #'evil-outer-arg))


(def-package! evil-commentary
  :commands (evil-commentary evil-commentary-yank evil-commentary-line)
  :config (evil-commentary-mode 1))


(def-package! evil-easymotion
  :defer 1
  :commands evilem-define
  :config
  (let ((prefix "g SPC"))
    (evilem-default-keybindings prefix)
    (evilem-define (kbd (concat prefix " n")) #'evil-ex-search-next)
    (evilem-define (kbd (concat prefix " N")) #'evil-ex-search-previous)
    (evilem-define (kbd (concat prefix " s")) 'evil-snipe-repeat
                   :pre-hook (save-excursion (call-interactively #'evil-snipe-s))
                   :bind ((evil-snipe-scope 'buffer)
                          (evil-snipe-enable-highlight)
                          (evil-snipe-enable-incremental-highlight)))
    (evilem-define (kbd (concat prefix " S")) #'evil-snipe-repeat-reverse
                   :pre-hook (save-excursion (call-interactively #'evil-snipe-s))
                   :bind ((evil-snipe-scope 'buffer)
                          (evil-snipe-enable-highlight)
                          (evil-snipe-enable-incremental-highlight))))

  (defvar +evil--snipe-repeat-fn
    (evilem-create #'evil-snipe-repeat
                   :bind ((evil-snipe-scope 'whole-buffer)
                          (evil-snipe-enable-highlight)
                          (evil-snipe-enable-incremental-highlight)))))


(def-package! evil-embrace
  :after evil-surround
  :config
  (setq evil-embrace-show-help-p nil)
  (evil-embrace-enable-evil-surround-integration)

  ;; Defuns
  (defun +evil--embrace-get-pair (char)
    (if-let (pair (cdr-safe (assoc (string-to-char char) evil-surround-pairs-alist)))
        pair
      (if-let (pair (assoc-default char embrace--pairs-list))
          (if-let (real-pair (and (functionp (embrace-pair-struct-read-function pair))
                                  (funcall (embrace-pair-struct-read-function pair))))
              real-pair
            (cons (embrace-pair-struct-left pair) (embrace-pair-struct-right pair)))
        (cons char char))))

  (defun +evil--embrace-escaped ()
    "Backslash-escaped surround character support for embrace."
    (let ((char (read-char "\\")))
      (if (eq char 27)
          (cons "" "")
        (let ((pair (+evil--embrace-get-pair (string char)))
              (text (if (sp-point-in-string) "\\\\%s" "\\%s")))
          (cons (format text (car pair))
                (format text (cdr pair)))))))

  (defun +evil--embrace-latex ()
    "LaTeX command support for embrace."
    (cons (format "\\%s{" (read-string "\\")) "}"))

  (defun +evil--embrace-elisp-fn ()
    "Elisp function support for embrace."
    (cons (format "(%s " (or (read-string "(") "")) ")"))

  ;; Add escaped-sequence support to embrace
  (push (cons ?\\ (make-embrace-pair-struct
                   :key ?\\
                   :read-function #'+evil--embrace-escaped
                   :left-regexp "\\[[{(]"
                   :right-regexp "\\[]})]"))
        (default-value 'embrace--pairs-list))

  ;; Add extra pairs
  (add-hook 'LaTeX-mode-hook #'embrace-LaTeX-mode-hook)
  (add-hook 'org-mode-hook   #'embrace-org-mode-hook)
  (add-hook! emacs-lisp-mode
    (embrace-add-pair ?\` "`" "'"))
  (add-hook! (emacs-lisp-mode lisp-mode)
    (embrace-add-pair-regexp ?f "([^ ]+ " ")" #'+evil--embrace-elisp-fn))
  (add-hook! (org-mode LaTeX-mode)
    (embrace-add-pair-regexp ?l "\\[a-z]+{" "}" #'+evil--embrace-latex)))


(def-package! evil-escape
  :commands evil-escape-mode
  :init
  (defun +evil|escape-disable () (evil-escape-mode -1))
  (defun +evil|escape-enable ()  (evil-escape-mode +1))
  ;; I only need evil-escape in insert and replace modes.
  (add-hook 'evil-insert-state-entry-hook  #'+evil|escape-enable)
  (add-hook 'evil-insert-state-exit-hook   #'+evil|escape-disable)
  (add-hook 'evil-replace-state-entry-hook #'+evil|escape-enable)
  (add-hook 'evil-replace-state-exit-hook  #'+evil|escape-disable)
  :config
  (setq evil-escape-key-sequence "jk"
        evil-escape-delay 0.25))


(def-package! evil-exchange
  :commands evil-exchange
  :config
  (defun +evil*exchange-off ()
    (if evil-exchange--overlays (evil-exchange-cancel)))
  (advice-add #'evil-force-normal-state :after #'+evil*exchange-off))


(def-package! evil-indent-plus
  :commands (evil-indent-plus-i-indent
             evil-indent-plus-a-indent
             evil-indent-plus-i-indent-up
             evil-indent-plus-a-indent-up
             evil-indent-plus-i-indent-up-down
             evil-indent-plus-a-indent-up-down)
  :init
  (+evil--textobj "i" #'evil-indent-plus-i-indent #'evil-indent-plus-a-indent)
  (+evil--textobj "I" #'evil-indent-plus-i-indent-up #'evil-indent-plus-a-indent-up)
  (+evil--textobj "J" #'evil-indent-plus-i-indent-up-down #'evil-indent-plus-a-indent-up-down))


(def-package! evil-matchit
  :commands (evilmi-jump-items evilmi-text-object global-evil-matchit-mode)
  :config (global-evil-matchit-mode 1)
  :init
  (+evil--textobj "%" #'evilmi-text-object)
  (defun +evil|simple-matchit ()
    "Force evil-matchit to favor simple bracket jumping. Helpful where the new
algorithm is just confusing, like in python or ruby."
    (setq-local evilmi-always-simple-jump t)))


(def-package! evil-multiedit
  :commands (evil-multiedit-match-all
             evil-multiedit-match-and-next
             evil-multiedit-match-and-prev
             evil-multiedit-match-symbol-and-next
             evil-multiedit-match-symbol-and-prev
             evil-multiedit-toggle-or-restrict-region
             evil-multiedit-next
             evil-multiedit-prev
             evil-multiedit-abort
             evil-multiedit-ex-match)
  :config (evil-multiedit-default-keybinds))


(def-package! evil-textobj-anyblock
  :commands (evil-numbers/inc-at-pt evil-numbers/dec-at-pt)
  :init
  (+evil--textobj "B" #'evil-textobj-anyblock-inner-block #'evil-textobj-anyblock-a-block))


(def-package! evil-search-highlight-persist :demand t
  :commands (evil-textobj-anyblock-inner-block evil-textobj-anyblock-a-block)
  :config
  (global-evil-search-highlight-persist t)
  (advice-add #'evil-force-normal-state :after #'evil-search-highlight-persist-remove-all))


(def-package! evil-snipe :demand t
  :init
  (setq evil-snipe-smart-case t
        evil-snipe-scope 'line
        evil-snipe-repeat-scope 'visible
        evil-snipe-override-evil-repeat-keys nil
        evil-snipe-char-fold t
        evil-snipe-aliases '((?\[ "[[{(]")
                             (?\] "[]})]")
                             (?\; "[;:]")))

  :config
  ;; (evil-snipe-mode +1)
  (evil-snipe-override-mode +1)
  ;; Switch to evil-easymotion/avy after first snipe
  (map! :map evil-snipe-parent-transient-map
        "C-;" (λ! (require 'evil-easymotion)
                  (call-interactively +evil--snipe-repeat-fn))))


(def-package! evil-surround
  :commands (global-evil-surround-mode
             evil-surround-edit
             evil-Surround-edit
             evil-surround-region)
  :config (global-evil-surround-mode 1))


(def-package! evil-visualstar
  :commands (global-evil-visualstar-mode
             evil-visualstar/begin-search
             evil-visualstar/begin-search-forward
             evil-visualstar/begin-search-backward)
  :config (global-evil-visualstar-mode 1))


;; A side-panel for browsing my project files. Inspired by vim's NERDTree.
(def-package! neotree
  :commands (neotree-show
             neotree-hide
             neotree-toggle
             neotree-dir
             neotree-find
             neo-global--with-buffer
             neo-global--window-exists-p)
  :config
  (setq neo-create-file-auto-open t
        neo-auto-indent-point nil
        neo-mode-line-type 'none
        neo-window-width 25
        neo-show-updir-line nil
        neo-theme 'nerd ; fallback
        neo-banner-message nil
        neo-show-hidden-files nil
        neo-hidden-regexp-list
        '(;; vcs folders
          "^\\.\\(git\\|hg\\|svn\\)$"
          ;; compiled files
          "\\.\\(pyc\\|o\\|elc\\|lock\\|css.map\\)$"
          ;; generated files, caches or local pkgs
          "^\\(node_modules\\|vendor\\|.\\(project\\|cask\\|yardoc\\|sass-cache\\)\\)$"
          ;; org-mode folders
          "^\\.\\(sync\\|export\\|attach\\)$"
          "~$"
          "^#.*#$"))

  (set! :evil-state 'neotree-mode 'motion)

  (push neo-buffer-name winner-boring-buffers)

  ;; Don't ask for confirmation when creating files
  (defun +evil*neotree-create-node (orig-fun &rest args)
    "Don't ask for confirmation when creating files"
    (cl-letf (((symbol-function 'yes-or-no-p) (lambda (&rest _) t)))
      (apply orig-fun args)))
  (advice-add #'neotree-create-node :around #'+evil*neotree-create-node)

  ;; Adding keybindings to `neotree-mode-map' wouldn't work for me (they get
  ;; overridden when the neotree buffer is spawned). So we bind them in a hook.
  (add-hook 'neo-after-create-hook #'+evil|neotree-init-keymap)
  (defun +evil|neotree-init-keymap (&rest _)
    (map! :Lm "\\\\"     'evil-window-prev
          :Lm "RET"      'neotree-enter
          :Lm "<return>" 'neotree-enter
          :Lm "ESC ESC"  'neotree-hide
          :Lm [return]   'neotree-enter
          :Lm "q"        'neotree-hide
          :Lm "J"        'neotree-select-next-sibling-node
          :Lm "K"        'neotree-select-previous-sibling-node
          :Lm "H"        'neotree-select-up-node
          :Lm "L"        'neotree-select-down-node
          :Lm "h"        '+evil/neotree-collapse-or-up
          :Lm "j"        'neotree-next-line
          :Lm "k"        'neotree-previous-line
          :Lm "l"        '+evil/neotree-expand-or-open
          :Lm "v"        'neotree-enter-vertical-split
          :Lm "s"        'neotree-enter-horizontal-split
          :Lm "c"        'neotree-create-node
          :Lm "d"        'neotree-delete-node
          :Lm "\C-r"     'neotree-refresh
          :Lm "r"        'neotree-rename-node
          :Lm "R"        'neotree-change-root)))