Commit 2322969f26ac

@@ -72,5 +72,15 @@ switch to it. Otherwise, create a new vterm shell."
   :init
   (require 'vterm))
 
+(use-package project-x
+  :after project
+  :config
+  (add-hook 'project-find-functions 'project-x-try-local 90)
+  (add-hook 'kill-emacs-hook 'project-x--window-state-write)
+  (add-to-list 'project-switch-commands
+               '(?j "Restore windows" project-x-windows) t)
+    :bind (("C-x p w" . project-x-window-state-save)
+           ("C-x p j" . project-x-window-state-load)))
+
 (provide 'config-projects)
 ;;; config-projects.el ends here

@@ -0,0 +1,217 @@
+;;; project-x.el --- Extra convenience features for project.el -*- lexical-binding: t -*-
+
+;; Copyright (C) 2021  Karthik Chikmagalur
+
+;; Author: Karthik Chikmagalur <karthik.chikmagalur@gmail.com>
+;; URL: https://github.com/karthink/project-x
+;; Version: 0.1.5
+;; Package-Requires: ((emacs "27.1"))
+
+;; This file is NOT part of GNU Emacs.
+
+;; This file 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.
+;;
+;; For a full copy of the GNU General Public License
+;; see <http://www.gnu.org/licenses/>.
+;;
+;;; Commentary:
+;;
+;; project-x provides some convenience features for project.el:
+;; - Recognize any directory with a `.project' file as a project.
+;; - Save and restore project files and window configurations across sessions
+;;
+;; COMMANDS:
+;;
+;; project-x-window-state-save : Save the window configuration of currently open project buffers
+;; project-x-window-state-load : Load a previously saved project window configuration
+;;
+;; CUSTOMIZATION:
+;;
+;; `project-x-window-list-file': File to store project window configurations
+;; `project-x-local-identifier': String matched against file names to decide if a
+;; directory is a project
+;; `project-x-save-interval': Interval in seconds between autosaves of the
+;; current project.
+;;
+;; by Karthik Chikmagalur
+;; <karthik.chikmagalur@gmail.com>
+
+;;; Code:
+
+(require 'project)
+(eval-when-compile (require 'subr-x))
+(eval-when-compile (require 'seq))
+(defvar project-prefix-map)
+(defvar project-switch-commands)
+(declare-function project-prompt-project-dir "project")
+(declare-function project--buffer-list "project")
+(declare-function project-buffers "project")
+
+(defgroup project-x nil
+  "Convenience features for the Project library."
+  :group 'project)
+
+;; Persistent project sessions
+;; -------------------------------------
+(defcustom project-x-window-list-file
+  (locate-user-emacs-file "project-window-list")
+  "File in which to save project window configurations by default."
+  :type 'file
+  :group 'project-x)
+
+(defcustom project-x-save-interval nil
+  "Saves the current project state with this interval.
+
+When set to nil auto-save is disabled."
+  :type '(choice (const :tag "Disabled" nil)
+                 integer)
+  :group 'project-x)
+
+(defvar project-x-window-alist nil
+  "Alist of window configurations associated with known projects.")
+
+(defvar project-x-save-timer nil
+  "Timer for auto-saving project state.")
+
+(defun project-x--window-state-write (&optional file)
+  "Write project window states to `project-x-window-list-file'.
+If FILE is specified, write to it instead."
+  (when project-x-window-alist
+    (require 'pp)
+    (unless file (make-directory (file-name-directory project-x-window-list-file) t))
+    (with-temp-file (or file project-x-window-list-file)
+      (insert ";;; -*- lisp-data -*-\n")
+      (let ((print-level nil) (print-length nil))
+        (pp project-x-window-alist (current-buffer))))
+    (message (format "Wrote project window state to %s" project-x-window-list-file))))
+
+(defun project-x--window-state-read (&optional file)
+  "Read project window states from `project-x-window-list-file'.
+If FILE is specified, read from it instead."
+  (and (or file
+           (file-exists-p project-x-window-list-file))
+       (with-temp-buffer
+         (insert-file-contents (or file project-x-window-list-file))
+         (condition-case nil
+             (if-let ((win-state-alist (read (current-buffer))))
+                 (setq project-x-window-alist win-state-alist)
+               (message (format "Could not read %s" project-x-window-list-file)))
+           (error (message (format "Could not read %s" project-x-window-list-file)))))))
+
+(defun project-x-window-state-save (&optional arg)
+  "Save current window state of project.
+With optional prefix argument ARG, query for project."
+  (interactive "P")
+  (when-let* ((dir (cond (arg (project-prompt-project-dir))
+                         ((project-current)
+                          (project-root (project-current)))))
+              (default-directory dir))
+    (unless project-x-window-alist (project-x--window-state-read))
+    (let ((file-list))
+      ;; Collect file-list of all the open project buffers
+      (dolist (buf
+               (funcall (if (fboundp 'project--buffers-list)
+                            #'project--buffers-list
+                          #'project-buffers)
+                        (project-current))
+               file-list)
+        (if-let ((file-name (or (buffer-file-name buf)
+                                (with-current-buffer buf
+                                  (and (derived-mode-p 'dired-mode)
+                                       dired-directory)))))
+            (push file-name file-list)))
+      (setf (alist-get dir project-x-window-alist nil nil 'equal)
+            (list (cons 'files file-list)
+                  (cons 'windows (window-state-get nil t)))))
+    (message (format "Saved project state for %s" dir))))
+
+(defun project-x-window-state-load (dir)
+  "Load the saved window state for project with directory DIR.
+If DIR is unspecified query the user for a project instead."
+  (interactive (list (project-prompt-project-dir)))
+  (unless project-x-window-alist (project-x--window-state-read))
+  (if-let* ((project-x-window-alist)
+            (project-state (alist-get dir project-x-window-alist
+                                      nil nil 'equal)))
+      (let ((file-list (alist-get 'files project-state))
+            (window-config (alist-get 'windows project-state)))
+        (dolist (file-name file-list nil)
+          (find-file file-name))
+        (window-state-put window-config nil 'safe)
+        (message (format "Restored project state for %s" dir)))
+    (message (format "No saved window state for project %s" dir))))
+
+(defun project-x-windows ()
+  "Restore the last saved window state of the chosen project."
+  (interactive)
+  (project-x-window-state-load (project-root (project-current))))
+
+;; Recognize directories as projects by defining a new project backend `local'
+;; -------------------------------------
+(defcustom project-x-local-identifier ".project"
+  "Filename(s) that identifies a directory as a project.
+
+You can specify a single filename or a list of names."
+  :type '(choice (string :tag "Single file")
+                 (repeat (string :tag "Filename")))
+  :group 'project-x)
+
+(cl-defmethod project-root ((project (head local)))
+  "Return root directory of current PROJECT."
+  (cdr project))
+
+(defun project-x-try-local (dir)
+  "Determine if DIR is a non-VC project.
+DIR must include a .project file to be considered a project."
+  (if-let ((root (if (listp project-x-local-identifier)
+                     (seq-some (lambda (n)
+                                 (locate-dominating-file dir n))
+                               project-x-local-identifier)
+                   (locate-dominating-file dir project-x-local-identifier))))
+      (cons 'local root)))
+
+;;;###autoload
+(define-minor-mode project-x-mode
+  "Minor mode to enable extra convenience features for project.el.
+When enabled, save and load project window states.
+Recognize any directory that contains (or whose parent
+contains) a special file as a project."
+  :global t
+  :version "0.10"
+  :lighter ""
+  :group 'project-x
+  (if project-x-mode
+      ;;Turning the mode ON
+      (progn
+        (add-hook 'project-find-functions 'project-x-try-local 90)
+        (add-hook 'kill-emacs-hook 'project-x--window-state-write)
+        (project-x--window-state-read)
+        (define-key project-prefix-map (kbd "w") 'project-x-window-state-save)
+        (define-key project-prefix-map (kbd "j") 'project-x-window-state-load)
+        (if (listp project-switch-commands)
+            (add-to-list 'project-switch-commands
+                         '(?j "Restore windows" project-x-windows) t)
+          (message "`project-switch-commands` is not a list, not adding 'restore windows' command"))
+        (when project-x-save-interval
+          (setq project-x-save-timer
+                (run-with-timer 0 (max project-x-save-interval 5)
+                                #'project-x-window-state-save))))
+    (remove-hook 'project-find-functions 'project-x-try-local 90)
+    (remove-hook 'kill-emacs-hook 'project-x--window-state-write)
+    (define-key project-prefix-map (kbd "w") nil)
+    (define-key project-prefix-map (kbd "j") nil)
+    (when (listp project-switch-commands)
+      (delete '(?j "Restore windows" project-x-windows) project-switch-commands))
+    (when (timerp project-x-save-timer)
+      (cancel-timer project-x-save-timer))))
+
+(provide 'project-x)
+;;; project-x.el ends here