path: root/lisp/ravi-init-completion.el

;;; ravi-init-completion.el --- selectrum/prescient/orderless/marginalia/embark/consult  -*- lexical-binding: t; -*-

;; Copyright (C) 2021  Ravi R Kiran

;; Author: Ravi R Kiran <aine.marina@gmail.com>
;; Keywords:

;; 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 this program.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Try out newfangled completion UI

;;; Code:

;; Use selectrum as completion UI with orderless for filtering and
;; prescient for frecency sorting

(use-package vlf)
(use-package sudo-edit)

(use-package orderless
  :if (member ravi/use-selection-system '(selectrum vertico))
  :custom (completion-styles '(orderless))
  :config
  (when (equal ravi/use-selection-system 'selectrum)
    (setq orderless-skip-highlighting (lambda () selectrum-is-active))))

(use-package selectrum
  :if (equal ravi/use-selection-system 'selectrum)
  :config
  (setq selectrum-highlight-candidates-function #'orderless-highlight-matches)
  (setq selectrum-max-window-height 22)
  (selectrum-mode +1)
  (bind-key "C-l" 'backward-kill-word selectrum-minibuffer-map)

  (autoload 'ffap-guesser "ffap")
  (setq minibuffer-default-add-function
        (defun minibuffer-default-add-function+ ()
          (with-selected-window (minibuffer-selected-window)
            (delete-dups
             (delq nil
                   (list (thing-at-point 'symbol)
                           (thing-at-point 'list)
                           (ffap-guesser)
                           (thing-at-point-url-at-point))))))))
(use-package selectrum-prescient
  :if (equal ravi/use-selection-system 'selectrum)
  :config
  (setq selectrum-prescient-enable-filtering nil)
  (selectrum-prescient-mode +1)
  (prescient-persist-mode +1))

(use-package vertico
  :if (equal ravi/use-selection-system 'vertico)
  :init
  (vertico-mode))

(defun ravi/bind-key-selection-system-map (key func)
  "Bind to appropriate minibuffer completion map"
  (bind-key key func
            (pcase ravi/use-selection-system
              ('selectrum selectrum-minibuffer-map)
              ('vertico vertico-map))))

(use-package marginalia
  :if (member ravi/use-selection-system '(selectrum vertico))
  :config (marginalia-mode))
(use-package embark
  :if (member ravi/use-selection-system '(selectrum vertico))
  :after (sudo-edit vlf)
  :commands (embark-act)
  :bind (("H-t" . embark-act)
         :map
         embark-file-map
         ("s" . sudo-edit)
         ("l" . vlf)
         ("G" . embark-magit-status))
  :init
  ;; Optionally replace the key help with a completing-read interface
  (setq prefix-help-command #'embark-prefix-help-command)
  (ravi/bind-key-selection-system-map "C-t" #'embark-act)
  :config
  (defun embark-magit-status (file)
    "Run `magit-status` on repo containing the embark target."
    (interactive "GFile: ")
    (magit-status (locate-dominating-file file ".git")))

  ;; Hide the mode line of the Embark live/completions buffers
  (add-to-list 'display-buffer-alist
               '("\\`\\*Embark Collect \\(Live\\|Completions\\)\\*"
                 nil
                 (window-parameters (mode-line-format . none)))))

(use-package consult
  :if (member ravi/use-selection-system '(selectrum vertico))
  :after (which-key)
  :bind (;; C-c bindings (mode-specific-map)
         ("C-c h" . consult-history)
         ("C-c m" . consult-mode-command)
         ("C-c b" . consult-bookmark)
         ("C-c k" . consult-kmacro)
         ;; C-x bindings (ctl-x-map)
         ("C-x M-:" . consult-complex-command)     ;; orig. repeat-complex-command
         ("C-x b" . consult-buffer)                ;; orig. switch-to-buffer
         ("C-x 4 b" . consult-buffer-other-window) ;; orig. switch-to-buffer-other-window
         ("C-x 5 b" . consult-buffer-other-frame)  ;; orig. switch-to-buffer-other-frame
         ;; Custom M-# bindings for fast register access
         ("M-#" . consult-register-load)
         ("M-'" . consult-register-store)          ;; orig. abbrev-prefix-mark (unrelated)
         ("C-M-#" . consult-register)
         ;; Other custom bindings
         ("M-y" . consult-yank-pop)                ;; orig. yank-pop
         ("<help> a" . consult-apropos)            ;; orig. apropos-command
         ;; M-g bindings (goto-map)
         ("M-g e" . consult-compile-error)
         ("M-g f" . consult-flymake)               ;; Alternative: consult-flycheck
         ;; Don't use consult-goto-line because avy-goto-line keeps fingers on home row
         ;; ("M-g g" . consult-goto-line)             ;; orig. goto-line
         ;; ("M-g M-g" . consult-goto-line)           ;; orig. goto-line
         ("M-g o" . consult-outline)               ;; Alternative: consult-org-heading
         ("M-g m" . consult-mark)
         ("M-g k" . consult-global-mark)
         ("M-g i" . consult-imenu)
         ("M-g I" . consult-imenu-multi)
         ;; M-s bindings (search-map)
         ("M-s f" . consult-find)
         ("M-s F" . consult-locate)
         ("M-s g" . consult-grep)
         ("M-s G" . consult-git-grep)
         ;; ("M-s r" . consult-ripgrep)
         ("M-i" . consult-line)
         ("M-s l" . consult-line)
         ("M-s L" . consult-line-multi)
         ("M-s m" . consult-multi-occur)
         ("M-s k" . consult-keep-lines)
         ("M-s u" . consult-focus-lines)
         ;; Isearch integration
         ("M-s e" . consult-isearch)
         :map isearch-mode-map
         ("M-e" . consult-isearch)                 ;; orig. isearch-edit-string
         ("M-s e" . consult-isearch)               ;; orig. isearch-edit-string
         ("M-s l" . consult-line)                  ;; needed by consult-line to detect isearch
         ("M-s L" . consult-line-multi)            ;; needed by consult-line to detect isearch
         :map consult-narrow-map
         ("C-r" . consult-narrow-cycle-backward)
         ("C-s" . consult-narrow-cycle-forward))

  ;; Enable automatic preview at point in the *Completions* buffer.
  ;; This is relevant when you use the default completion UI,
  ;; and not necessary for Vertico, Selectrum, etc.
  ;; :hook (completion-list-mode . consult-preview-at-point-mode)

  ;; The :init configuration is always executed (Not lazy)
  :init

  ;; Optionally configure the register formatting. This improves the register
  ;; preview for `consult-register', `consult-register-load',
  ;; `consult-register-store' and the Emacs built-ins.
  (setq register-preview-delay 0
        register-preview-function #'consult-register-format)

  ;; Optionally tweak the register preview window.
  ;; This adds thin lines, sorting and hides the mode line of the window.
  (advice-add #'register-preview :override #'consult-register-window)

  ;; Optionally replace `completing-read-multiple' with an enhanced version.
  (advice-add #'completing-read-multiple :override #'consult-completing-read-multiple)

  ;; Use Consult to select xref locations with preview
  (setq xref-show-xrefs-function #'consult-xref
        xref-show-definitions-function #'consult-xref)

  ;; Configure other variables and modes in the :config section,
  ;; after lazily loading the package.
  :config

  ;; Optionally configure preview. The default value
  ;; is 'any, such that any key triggers the preview.
  ;; (setq consult-preview-key 'any)
  (setq consult-preview-key (kbd "C-o"))
  ;; (setq consult-preview-key (list (kbd "<S-down>") (kbd "<S-up>")))
  ;; For some commands and buffer sources it is useful to configure the
  ;; :preview-key on a per-command basis using the `consult-customize' macro.
  (consult-customize
   consult-theme
   :preview-key '(:debounce 0.2 any)
   consult-ripgrep consult-git-grep consult-grep consult-xref
   :preview-key 'any
   consult-bookmark consult-recent-file
   consult--source-file consult--source-project-file consult--source-bookmark
   :preview-key "C-o")
  (consult-customize consult-buffer :preview-key nil) ; preview is just too intrusive

  ;; Optionally configure the narrowing key.
  ;; Both < and C-+ work reasonably well.
  (setq consult-narrow-key "<") ;; (kbd "C-+")

  ;; Optionally make narrowing help available in the minibuffer.
  ;; You may want to use `embark-prefix-help-command' or which-key instead.
  (define-key consult-narrow-map (vconcat consult-narrow-key "?") #'consult-narrow-help)

  ;; Optionally configure a function which returns the project root directory.
  ;; There are multiple reasonable alternatives to chose from.
  ;;;; 1. project.el (project-roots)
  ;; (setq consult-project-root-function
  ;;       (lambda ()
  ;;         (when-let (project (project-current))
  ;;           (car (project-roots project)))))
  ;;;; 2. projectile.el (projectile-project-root)
  (autoload 'projectile-project-root "projectile")
  (setq consult-project-root-function #'projectile-project-root)
  ;;;; 3. vc.el (vc-root-dir)
  ;; (setq consult-project-root-function #'vc-root-dir)
  ;;;; 4. locate-dominating-file
  ;; (setq consult-project-root-function (lambda () (locate-dominating-file "." ".git")))

  ;; First line as default is entirely useless
  (consult-customize
   consult-line consult-line-multi
   :default nil)

  ;; Replace by embark-prefix-help-command?
  (defun immediate-which-key-for-narrow (fun &rest args)
    (let* ((refresh t)
           (timer (and consult-narrow-key
                       (memq :narrow args)
                       (run-at-time 0.05 0.05
                                    (lambda ()
                                      (if (eq last-input-event (elt consult-narrow-key 0))
                                          (when refresh
                                            (setq refresh nil)
                                            (which-key--update))
                                        (setq refresh t)))))))
      (unwind-protect
          (apply fun args)
        (when timer
          (cancel-timer timer)))))
  (advice-add #'consult--read :around #'immediate-which-key-for-narrow)

  (defun consult-narrow-cycle-backward ()
    "Cycle backward through the narrowing keys."
    (interactive)
    (when consult--narrow-keys
      (consult-narrow
       (if consult--narrow
           (let ((idx (seq-position consult--narrow-keys
                                    (assq consult--narrow consult--narrow-keys))))
             (unless (eq idx 0)
               (car (nth (1- idx) consult--narrow-keys))))
         (caar (last consult--narrow-keys))))))

  (defun consult-narrow-cycle-forward ()
    "Cycle forward through the narrowing keys."
    (interactive)
    (when consult--narrow-keys
      (consult-narrow
       (if consult--narrow
           (let ((idx (seq-position consult--narrow-keys
                                    (assq consult--narrow consult--narrow-keys))))
             (unless (eq idx (1- (length consult--narrow-keys)))
               (car (nth (1+ idx) consult--narrow-keys))))
         (caar consult--narrow-keys)))))
  )

(use-package embark-consult
  :if (member ravi/use-selection-system '(selectrum vertico))
  :after (embark consult)
  :demand t ; only necessary if you have the hook below
  ;; if you want to have consult previews as you move around an
  ;; auto-updating embark collect buffer
  :hook
  (embark-collect-mode . consult-preview-at-point-mode))

(use-package dash-docs
  :if (member ravi/use-selection-system '(selectrum vertico))
  :bind (("M-s d" . 'ravi/dash)
         ("M-s D" . 'ravi/dash-at-point))
  :config
  (require 'cl-lib)                   ; for cl-remove-duplicates, cl-find-if
  (require 'subr-x)                   ; for when-let

  (defvar ravi/dash-history-input nil)
  (defvar ravi/dash--results nil
    "Stores the previously retrieved docset results")
  (defvar-local ravi/dash-docsets nil
    "Docsets to use for this buffer")

  (advice-add #'dash-docs-buffer-local-docsets :around
              (lambda (old-fun &rest args)
                (let ((old (apply old-fun args)))
                  (cl-remove-duplicates (append old ravi/dash-docsets)))))

  (defun ravi/dash--collection (s &rest _)
    "Given a string S, query docsets and retrieve result."
    (message "Trying to search for: %s" (prin1-to-string s))
    (setq ravi/dash--results (dash-docs-search s))
    (mapcar 'car ravi/dash--results))

  (defun ravi/dash--browse-matching-result (match)
    "Given a MATCH, find matching result and browse it's url."
    (when-let ((result
                (cdr (cl-find-if (lambda (e)
                                   (string= match (car e))) ravi/dash--results))))
      (dash-docs-browse-url result)))

  ;; The following does not work, because vertico and selectrum don't support dynamic completions
  (defun ravi/dash (&optional initial)
    "Query dash docsets.
INITIAL will be used as the initial input, if given."
    (interactive)
    (dash-docs-initialize-debugging-buffer)
    (dash-docs-create-buffer-connections)
    (dash-docs-create-common-connections)
    (if t
        (ravi/dash--browse-matching-result
         (let ((cb (current-buffer)))
           (completing-read
            "Documentation for: "
            ;; (completion-table-dynamic (lambda (s) (with-current-buffer cb (ravi/dash--collection s))))
            (completion-table-dynamic #'ravi/dash--collection t)
            nil                         ; predicate
            t                           ; require-match
            nil                         ; initial-input
            ravi/dash-history-input     ; history
            (when-let ((sym (thing-at-point 'symbol))) (substring-no-properties sym))))) ; default, a.k.a future history
      (message "%s" (prin1-to-string (ravi/dash--collection "C++ throw")))))

  (defun ravi/dash-at-point-what-it-should-be ()
    "Bring up a `ravi/dash' search interface with symbol at point."
    (interactive)
    (ravi/dash
     (substring-no-properties (or (thing-at-point 'symbol) ""))))

  (defun ravi/dash-at-point ()
    "Bring up a `ravi/dash' search interface with symbol at point."
    (interactive)
    (dash-docs-initialize-debugging-buffer)
    (dash-docs-create-buffer-connections)
    (dash-docs-create-common-connections)
    (if-let* ((sym (thing-at-point 'symbol))
              (sym-only (substring-no-properties sym))
              (cb (current-buffer))
              (table (with-current-buffer cb (ravi/dash--collection sym-only)))
              (result (completing-read (format "Documentation for '%s':" sym-only)
                                       table nil t nil ravi/dash-history-input)))
        (progn
          (ravi/dash--browse-matching-result result)
          (add-to-list 'ravi/dash-history-input sym-only))
      (user-error "No symbol at point or documentation not found")))
  )

(provide 'ravi-init-completion)
;;; ravi-init-completion.el ends here