;;; ibuffer-vc.el --- Group ibuffer's list by VC project, or show VC status
;;
;; Copyright (C) 2011-2014 Steve Purcell
;;
;; Author: Steve Purcell <steve@sanityinc.com>
;; Keywords: themes
;; Package-Version: 20181025.324
;; Package-Requires: ((cl-lib "0.2"))
;; X-URL: http://github.com/purcell/ibuffer-vc
;; URL: http://github.com/purcell/ibuffer-vc
;; Version: DEV
;;
;; 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 <http://www.gnu.org/licenses/>.
;;
;;; Commentary:
;;
;; Adds functionality to ibuffer for grouping buffers by their parent
;; vc root directory, and for displaying and/or sorting by the vc
;; status of listed files.
;;
;;; Use:
;;
;; To group buffers by vc parent dir:
;;
;;   M-x ibuffer-vc-set-filter-groups-by-vc-root
;;
;; or, make this the default:
;;
;;   (add-hook 'ibuffer-hook
;;     (lambda ()
;;       (ibuffer-vc-set-filter-groups-by-vc-root)
;;       (unless (eq ibuffer-sorting-mode 'alphabetic)
;;         (ibuffer-do-sort-by-alphabetic))))
;;
;; Alternatively, use `ibuffer-vc-generate-filter-groups-by-vc-root'
;; to programmatically obtain a list of filter groups that you can
;; combine with your own custom groups.
;;
;; To include vc status info in the ibuffer list, add either
;; vc-status-mini or vc-status to `ibuffer-formats':
;;
;; (setq ibuffer-formats
;;       '((mark modified read-only vc-status-mini " "
;;               (name 18 18 :left :elide)
;;               " "
;;               (size 9 -1 :right)
;;               " "
;;               (mode 16 16 :left :elide)
;;               " "
;;               (vc-status 16 16 :left)
;;               " "
;;               filename-and-process)))
;;
;; To sort by vc status, use `ibuffer-do-sort-by-vc-status', which can
;; also be selected by repeatedly executing
;; `ibuffer-toggle-sorting-mode' (bound to "," by default).
;;
;;; Code:

;; requires

(require 'ibuffer)
(require 'ibuf-ext)
(require 'vc-hooks)
(require 'cl-lib)


(defgroup ibuffer-vc nil
  "Group ibuffer entries according to their version control status."
  :prefix "ibuffer-vc-"
  :group 'convenience)

(defcustom ibuffer-vc-skip-if-remote t
  "If non-nil, don't query the VC status of remote files."
  :type 'boolean
  :group 'ibuffer-vc)

(defcustom ibuffer-vc-include-function 'identity
  "A function which tells whether a given file should be grouped.

The function is passed a filename, and should return non-nil if the file
is to be grouped.

This option can be used to exclude certain files from the grouping mechanism."
  :type 'function
  :group 'ibuffer-vc)

;;; Group and filter ibuffer entries by parent vc directory

(defun ibuffer-vc--include-file-p (file)
  "Return t iff FILE should be included in ibuffer-vc's filtering."
  (and file
       (or (null ibuffer-vc-skip-if-remote)
           (not (file-remote-p file)))
       (funcall ibuffer-vc-include-function file)))

(defun ibuffer-vc--deduce-backend (file)
  "Return the vc backend for FILE, or nil if not under VC supervision."
  (if (fboundp 'vc-responsible-backend)
      (ignore-errors (vc-responsible-backend file))
    (or (vc-backend file)
        (cl-loop for backend in vc-handled-backends
                 when (vc-call-backend backend 'responsible-p file)
                 return backend))))

(defun ibuffer-vc-root (buf)
  "Return a cons cell (backend-name . root-dir) for BUF.
If the file is not under version control, nil is returned instead."
  (let ((file-name (with-current-buffer buf
                     (file-truename (or buffer-file-name
					default-directory)))))
    (when (ibuffer-vc--include-file-p file-name)
      (let ((backend (ibuffer-vc--deduce-backend file-name)))
        (when backend
          (let* ((root-fn-name (intern (format "vc-%s-root" (downcase (symbol-name backend)))))
                 (root-dir
                  (cond
                   ((fboundp root-fn-name) (funcall root-fn-name file-name)) ; git, svn, hg, bzr (at least)
                   ((memq backend '(darcs DARCS)) (vc-darcs-find-root file-name))
                   ((memq backend '(cvs CVS)) (vc-find-root file-name "CVS"))
                   ((memq backend '(rcs RCS)) (or (vc-find-root file-name "RCS")
                                                  (concat file-name ",v")))
                   ((memq backend '(src SRC)) (or (vc-find-root file-name ".src")
                                                  (concat file-name ",v")))
                   (t (error "ibuffer-vc: don't know how to find root for vc backend '%s' - please submit a bug report or patch" backend)))))
            (cons backend root-dir)))))))

(defun ibuffer-vc-read-filter ()
  "Read a cons cell of (backend-name . root-dir)."
  (cons (car (read-from-string
              (completing-read "VC backend: " vc-handled-backends nil t)))
        (read-directory-name "Root directory: " nil nil t)))

(define-ibuffer-filter vc-root
    "Toggle current view to buffers with vc root dir QUALIFIER."
  (:description "vc root dir"
                :reader (ibuffer-vc-read-filter))
  (ibuffer-awhen (ibuffer-vc-root buf)
    (equal qualifier it)))

;;;###autoload
(defun ibuffer-vc-generate-filter-groups-by-vc-root ()
  "Create a set of ibuffer filter groups based on the vc root dirs of buffers."
  (let ((roots (ibuffer-remove-duplicates
                (delq nil (mapcar 'ibuffer-vc-root (buffer-list))))))
    (mapcar (lambda (vc-root)
              (cons (format "%s:%s" (car vc-root) (cdr vc-root))
                    `((vc-root . ,vc-root))))
            roots)))

;;;###autoload
(defun ibuffer-vc-set-filter-groups-by-vc-root ()
  "Set the current filter groups to filter by vc root dir."
  (interactive)
  (setq ibuffer-filter-groups (ibuffer-vc-generate-filter-groups-by-vc-root))
  (message "ibuffer-vc: groups set")
  (let ((ibuf (get-buffer "*Ibuffer*")))
    (when ibuf
        (with-current-buffer ibuf
          (pop-to-buffer ibuf)
          (ibuffer-update nil t)))))


;;; Display vc status info in the ibuffer list

(defun ibuffer-vc--state (file)
  "Return the `vc-state' for FILE, or nil if unregistered."
  (ignore-errors (vc-state file)))

(defun ibuffer-vc--status-string ()
  "Return a short string to represent the current buffer's status."
  (when (and buffer-file-name (ibuffer-vc--include-file-p buffer-file-name))
    (let ((state (ibuffer-vc--state buffer-file-name)))
      (if state
          (symbol-name state)
        "-"))))

;;;###autoload (autoload 'ibuffer-make-column-vc-status "ibuffer-vc")
(define-ibuffer-column vc-status
  (:name "VC status")
  (ibuffer-vc--status-string))

;;;###autoload (autoload 'ibuffer-make-column-vc-status-mini "ibuffer-vc")
(define-ibuffer-column vc-status-mini
  (:name "V")
  (if (and buffer-file-name (ibuffer-vc--include-file-p buffer-file-name))
      (let ((state (ibuffer-vc--state buffer-file-name)))
        (cond
         ((eq 'added state) "A")
         ((eq 'removed state) "D")
         ((eq 'up-to-date state) "=")
         ((eq 'edited state) "*")
         ((eq 'needs-update state) "O")
         ((memq state '(conflict needs-merge unlocked-changes)) "!")
         ((eq 'ignored state) "I")
         ((memq state '(() unregistered missing)) "?")))
    " "))

;;;###autoload (autoload 'ibuffer-do-sort-by-vc-status "ibuffer-vc")
(define-ibuffer-sorter vc-status
  "Sort the buffers by their vc status."
  (:description "vc status")
  (let ((file1 (with-current-buffer (car a)
                 buffer-file-name))
        (file2 (with-current-buffer (car b)
                 buffer-file-name)))
    (if (and file1 file2)
        (string-lessp (with-current-buffer (car a)
                        (ibuffer-vc--status-string))
                      (with-current-buffer (car b)
                        (ibuffer-vc--status-string)))
      (not (null file1)))))


(provide 'ibuffer-vc)
;;; ibuffer-vc.el ends here