support ivy-occur-grep-mode; refactor code

README.org

@@ -48,20 +48,29 @@ If you want to set up this minor mode further:
 (workgroups-mode 1)   ; put this one at the bottom of .emacs
 #+end_src
 ** Tips (OPTIONAL)
-You can use =M-x customize-group workgroups= to see all variables and
-faces to change.
-
+*** Change workgroups session file
+Use below code
 #+begin_src elisp
-;; Change workgroups session file
 (setq wg-session-file "~/.emacs.d/.emacs_workgroups")
 #+end_src
-
-Hooks' names can tell when they are executed
-
+*** Support some special buffer,
+Here is minimum sample code to support =ivy-occur-grep-mode=,
 #+begin_src elisp
-wg-after-switch-to-workgroup-hook
+(with-eval-after-load 'workgroups2
+  ;; provide major mode, package to require, and functions
+  (wg-support 'ivy-occur-grep-mode 'ivy
+              `((serialize . ,(lambda (_buffer)
+                                (list default-directory
+                                      (base64-encode-string (buffer-string) t))))
+                (deserialize . ,(lambda (buffer _vars)
+                                  (switch-to-buffer (wg-buf-name buffer))
+                                  (setq default-directory (nth 0 _vars))
+                                  (insert (base64-decode-string (nth 1 _vars)))
+                                  ;; easier than `ivy-occur-grep-mode' to set up
+                                  (grep-mode)
+                                  ;; need return current buffer at the end of function
+                                  (current-buffer))))))
 #+end_src
-
 ** License
 workgroups2 is free software: you can redistribute it and/or modify it under the terms of the [[https://github.com/raw/redguardtoo/workgroups2/master/LICENSE][GNU General Public License]] as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
 

src/workgroups2-sdk.el

@@ -0,0 +1,55 @@
+;;; workgroups2-sdk.el --- sdk of workgroups2  -*- lexical-binding: t -*-
+
+;; This file is NOT part of GNU Emacs.
+
+;; 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, 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:
+
+;;
+
+;;; Code:
+(require 'cl-lib)
+
+(defvar wg-special-buffer-serdes-functions
+  '(wg-serialize-comint-buffer)
+  "Functions providing serialization/deserialization for complex buffers.
+
+Use `wg-support' macro and this variable will be filled
+automatically.
+
+An entry should be either a function symbol or a lambda, and should
+accept a single Emacs buffer object as an argument.
+
+When a buffer is to be serialized, it is passed to each of these
+functions in turn until one returns non-nil, or the list ends.  A
+return value of nil indicates that the function can't handle
+buffers of that type.  A non-nil return value indicates that it
+can.  The first non-nil return value becomes the buffer's special
+serialization data.  The return value should be a cons, with a
+deserialization function (a function symbol or a lambda) as the car,
+and any other serialization data as the cdr.
+
+When it comes time to deserialize the buffer, the deserialization
+function (the car of the cons mentioned above) is passed the
+wg-buf object, from which it should restore the buffer.  The
+special serialization data itself can be accessed
+with (cdr (wg-buf-special-data <wg-buf>)).  The deserialization
+function must return the restored Emacs buffer object.
+
+See the definitions of the functions in this list for examples of
+how to write your own.")
+
+(provide 'workgroups2-sdk)
+;;; workgroups2-sdk.el ends here