jao-eww-session: make do sans timers

1 files changed, 40 insertions, 170 deletions

diff --git a/lib/net/jao-eww-session.el b/lib/net/jao-eww-session.el
index 9970481..d3bc5b2 100644
--- a/lib/net/jao-eww-session.el
+++ b/lib/net/jao-eww-session.el
@@ -1,9 +1,9 @@
-;;; jao-eww-session.el --- Persistent emacs-eww sessions -*- lexical-binding: t; -*-
+;;; jao-eww-session.el --- Persistent eww sessions -*- lexical-binding: t; -*-
 
 ;; Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2012, 2021  Jose A Ortega Ruiz
 
 ;; Author: Jose A Ortega Ruiz <jao@gnu.org>
-;; Version: 0.3.6
+;; Version: 0.4
 ;; Keywords: hypermedia, eww, WWW
 
 ;; This file is free software; you can redistribute it and/or modify
@@ -23,133 +23,20 @@
 
 ;;; Commentary:
 
-;; INTRODUCTION:
-;;
-;; jao-eww-session provides persistent emacs-eww browsing sessions. When
+;; jao-eww-session provides persistent eww browsing sessions. When
 ;; quitting eww (or, if you request it, at any other time while using
 ;; it) you can save the current eww session (that is, the set of open
-;; tabs and the URLs they're visiting). Upon restarting emacs-eww
-;; (possibly after restarting Emacs itself) you'll have the possibity
-;; of recovering the saved session (that is, of re-opening the saved
-;; tabs and URLs). You also have at your disposal a command to recover
-;; the saved session at any other time.
-;;
-;; INSTALLATION:
-;;
-;; Just put this file somewhere on your Emacs load path and add the
-;; following line to your .emacs file:
-;;
-;;   (require 'jao-eww-session)
-;;
-;; After restarting Emacs (or evaluating the form above), each time
-;; you start emacs-eww with 'eww' you'll get a prompt asking whether
-;; your last browsing session should be loaded. Likewise, when
-;; quitting the browser, you'll have the possibility of saving your
-;; current session (overwriting the previous one).
-;;
-;; In addition, two new interactive functions are defined:
+;; tabs and the URLs they're visiting). Upon restarting emacs, you'll
+;; have the possibity of recovering the saved session (that is, of
+;; re-opening the saved tabs and URLs). You also have at your disposal
+;; a command to recover the saved session at any other time, via the
+;; commands:
 ;;
 ;;   jao-eww-session-load  --  load the last stored session
 ;;   jao-eww-session-save  --  save the current session
 ;;
-;; These functions can be invoked at any time while running emacs-eww.
-;; Optionally, you can bind them to key shortcuts with the proper
-;; variations of the following elisp magic in your .emacs:
-;;  (defun eww-add-keys ()
-;;    (define-key eww-mode-map "S" 'jao-eww-session-save)
-;;    (define-key eww-mode-map "L" 'jao-eww-session-load))
-;;  (add-hook 'eww-mode-hook 'eww-add-keys)
-;;
-;; CUSTOMIZATION:
-;;
-;; A new customization group, jao-eww-session, is available. There you can
+;; A customization group, jao-eww-session, is available. There you can
 ;; customize the following variables:
-;;
-;;   jao-eww-session-load-always     -- if t, `jao-eww-session-load' will *not* ask
-;;                                for confirmation (default nil)
-;;   jao-eww-session-save-always     -- if t, `jao-eww-session-save' will *not* ask
-;;                                for confirmation (default nil)
-;;   jao-eww-session-show-titles     -- if t, the load prompt will list the
-;;                                session URL titles (default t)
-;;   jao-eww-session-duplicate-tabs  -- what to do when loading a session that
-;;                                contains a URL already open
-;;   jao-eww-session-file            -- the file where eww session info
-;;                                is stored (default "~/.jao-eww-session")
-;;   jao-eww-session-autosave-period -- the period, in seconds, for automatic
-;;                                session backup file updating.
-;;
-;;
-;; You can also customize them in your .emacs file, to wit:
-;;
-;;   (setq jao-eww-session-file "~/.emacs.d/jao-eww-session")
-;;   (setq jao-eww-session-save-always nil)
-;;   (setq jao-eww-session-load-always nil)
-;;   (setq jao-eww-session-show-titles t)
-;;   (setq jao-eww-session-duplicate-tabs 'ask) ;  'never, 'always, 'ask
-;;
-;; HISTORY:
-;;
-;;   Version 0.4 (March, 2021):
-;;
-;;     - Migrated to eww.
-;;
-;;   Version 0.3.7 :
-;;
-;;     - `jao-w3m-session-deactivate-builtin-sessions', to do what it
-;;       says.
-;;
-;;   Version 0.3.6 (Sat Apr 19, 2008):
-;;
-;;     - eww-session -> jao-eww-session to avoid collisions with
-;;       emacs-eww's session manager.
-;;
-;;   Version 0.3.5 (Sun Jan 14, 2007):
-;;
-;;     - automatic session backup every `jao-w3m-session-autosave-period'
-;;       seconds.
-;;
-;;   Version 0.3.4 (Wed Jul 19, 2006):
-;;
-;;     - save session file on quitting Emacs (without using
-;;       desktop.el)
-;;
-;;   Version 0.3.3 (Thu Jun  8, 2006):
-;;
-;;     - save session file with pretty print.
-;;     - handle correctly multiple emacs-eww (re)starts during a
-;;       single emacs session.
-;;     - save URLs in hexified form to allow & in them.
-;;     - code cleanup.
-;;
-;;   Version 0.3.2 (Mon Sep 29, 2003):
-;;
-;;     - bug fix: when searching or going to home/bookmarks/etc,
-;;       keep the current tab's focus.
-;;
-;;   Version 0.3.1 (Tue Aug 26, 2003):
-;;
-;;     - type of `jao-w3m-session-file' set to 'file' in customisation
-;;       buffer.
-;;     - bug fix: syntax error due to a typo in `jao-w3m-session-file'
-;;
-;;   Version 0.3 (Mon Aug 25, 2003):
-;;
-;;     - the load session tab lists the titles of the session's pages
-;;       (customizable via 'jao-eww-session-show-titles').
-;;     - the duplicated tab prompt displays also the URL's title.
-;;     - bug fix: active tab in session now is correctly saved.
-;;
-;;   Version 0.2 (Fri Aug 22, 2003):
-;;
-;;     - the session info now includes the active tab, which gets
-;;       displayed when the session is reloaded.
-;;     - when reloading a session in a running emacs-w3m, if the
-;;       session contains a URL that is already being displayed by the
-;;       browser, the tab can be reused or duplicated (customizable
-;;       via `jao-w3m-session-duplicate-tabs').
-;;
-;;   Version 0.1 (Wed Aug 20, 2003) -- Initial release.
-;;
 
 ;;; Code:
 
@@ -193,28 +80,28 @@ the session is already displayed in a eww tab, jao-eww-session can:
   "File to save the eww session data."
   :type 'file)
 
-(defvar jao-eww-session-autosave-period 180
-  "A backup of the current session is saved with this period (in secs).")
-
 ;;; Internals:
 
 ;;;; auxiliary functions
 
 (defvar jao-eww-current-session '(jao-eww-session 0 nil))
 
-(defun jao-eww-session--list-buffers ()
-  (seq-filter (lambda (b) (with-current-buffer b (derived-mode-p 'eww-mode)))
+(defun jao-eww-session--list-buffers (&optional skip)
+  (seq-filter (lambda (b)
+                (when (not (eq b skip))
+                  (with-current-buffer b (derived-mode-p 'eww-mode))))
               (buffer-list)))
 
 (defun jao-eww--current-url ()
   (when-let (url (eww-current-url)) (url-encode-url url)))
 
-(defun jao-eww-session--current-urls ()
+(defun jao-eww-session--current-urls (&optional skip-current)
   (let ((urls)
         (cb (current-buffer))
         (pos 0)
         (count 0))
-    (dolist (b (jao-eww-session--list-buffers) (list pos (reverse urls)))
+    (dolist (b (jao-eww-session--list-buffers (when skip-current cb))
+               (list pos (reverse urls)))
       (set-buffer b)
       (when-let (url (jao-eww--current-url))
         (when (eq b cb) (setq pos count))
@@ -233,10 +120,10 @@ the session is already displayed in a eww tab, jao-eww-session can:
   (let ((s (or s jao-eww-current-session)))
     (mapcar 'cdr (nth 2 s))))
 
-(defun jao-eww-session-current (&optional s)
+(defun jao-eww-session--update-current (&optional skip-current)
   (save-current-buffer
     (setq jao-eww-current-session
-          (or s (cons 'jao-eww-session (jao-eww-session--current-urls))))))
+          (cons 'jao-eww-session (jao-eww-session--current-urls skip-current)))))
 
 (defun jao-eww-session--find-dups (urls)
   (seq-filter
@@ -259,7 +146,7 @@ the session is already displayed in a eww tab, jao-eww-session can:
                         (format "Load last eww session %S? "
                                 (jao-eww-session-titles new-session))
                       "Load last eww session? "))))
-      (jao-eww-session-current new-session))))
+      (setq jao-eww-current-session new-session))))
 
 (defun jao-eww-session-from-file (fname)
   (let ((fname (jao-eww-session--check--backup fname)))
@@ -272,21 +159,18 @@ the session is already displayed in a eww tab, jao-eww-session can:
 
 (defun jao-eww-session-not-empty () (> (length (jao-eww-session-urls)) 0))
 
-(defun jao-eww-session--to--file (filename &optional is-auto)
+(defun jao-eww-session--to--file (filename &optional is-auto skip)
   (require 'pp)
   (when (jao-eww-session-not-empty)
-    (let ((inhibit-message is-auto))
+    (let ((inhibit-message is-auto)
+          (session (jao-eww-session--update-current skip)))
       (with-temp-buffer
         (insert ";;;; File generated by jao-eww-session. DO NOT EDIT!\n")
-        (pp (jao-eww-session-current) (current-buffer))
+        (pp session (current-buffer))
         (insert "\n" ";;;; End of "
                 (file-name-nondirectory jao-eww-session-file) "\n")
         (write-region (point-min) (point-max) (expand-file-name filename))))))
 
-(defun jao-eww-session-current-to-file ()
-  (jao-eww-session--to--file jao-eww-session-file))
-
-(defvar jao-eww-session--timer nil)
 (defun jao-eww-session--backup-name (fname)
   (concat (expand-file-name fname) ".bak"))
 
@@ -297,19 +181,16 @@ the session is already displayed in a eww tab, jao-eww-session can:
         bfname
       fname)))
 
-(defun jao-eww-session--save-backup ()
-  (jao-eww-session--to--file (jao-eww-session--backup-name jao-eww-session-file) t))
+(defun jao-eww-session--save-backup (&optional skip)
+  (let ((f (jao-eww-session--backup-name jao-eww-session-file)))
+    (jao-eww-session--to--file t skip)))
 
-(defun jao-eww-session--restart--autosave ()
-  (when (> jao-eww-session-autosave-period 0)
-    (when jao-eww-session--timer (cancel-timer jao-eww-session--timer))
-    (setq jao-eww-session--timer
-          (run-at-time jao-eww-session-autosave-period
-                       jao-eww-session-autosave-period
-                       'jao-eww-session--save-backup))))
+(defun jao-eww-session--save-backup-1 ()
+  (when (derived-mode-p 'eww-mode) (jao-eww-session--save-backup t)))
 
 ;;;; save session on checkpoints
-(add-to-list 'kill-emacs-query-functions #'jao-eww-session-save)
+(add-hook 'kill-emacs-query-functions #'jao-eww-session-save)
+(add-hook 'kill-buffer-hook #'jao-eww-session--save-backup-1)
 (add-hook 'eww-after-render-hook #'jao-eww-session--save-backup)
 (advice-add 'eww-back-url :after #'jao-eww-session--save-backup)
 (advice-add 'eww-forward-url :after #'jao-eww-session--save-backup)
@@ -323,33 +204,22 @@ the session is already displayed in a eww tab, jao-eww-session can:
   (interactive)
   (when (and (jao-eww-session-not-empty)
              (or jao-eww-session-save-always (y-or-n-p "Save eww session? ")))
-    (jao-eww-session-current-to-file))
+    (jao-eww-session--to--file jao-eww-session-file))
   t)
 
 ;;;###autoload
 (defun jao-eww-session-load ()
   "Load last stored session into eww."
   (interactive)
-  (let ((s (jao-eww-session-load-aux)))
-    (when s
-      (jao-eww-session--restart--autosave)
-      (let* ((urls (jao-eww-session-urls s))
-             (offset (jao-eww-session-offset s))
-             (buffers (unless (equal jao-eww-session-duplicate-tabs 'always)
-                        (jao-eww-session--find-dups urls))))
-        (dolist (url urls) (eww url 4))
-        (seq-each #'kill-buffer buffers)
-        (unless (zerop offset)
-          (switch-to-buffer (nth offset (jao-eww-session--list-buffers))))))))
-
-;;;###autoload
-(defun jao-eww-session-set-autosave-period (secs)
-  "Set new value for the period between session backup autosaves."
-  (interactive "p")
-  (let ((secs (or secs (read-number "New period (secs): " 0))))
-    (when (> secs 0)
-      (setq jao-eww-session-autosave-period secs)
-      (jao-eww-session--restart--autosave))))
+  (when-let ((s (jao-eww-session-load-aux)))
+    (let* ((urls (jao-eww-session-urls s))
+           (offset (jao-eww-session-offset s))
+           (buffers (unless (equal jao-eww-session-duplicate-tabs 'always)
+                      (jao-eww-session--find-dups urls))))
+      (dolist (url urls) (eww url 4))
+      (seq-each #'kill-buffer buffers)
+      (unless (zerop offset)
+        (switch-to-buffer (nth offset (jao-eww-session--list-buffers)))))))
 
 (provide 'jao-eww-session)
 ;;; jao-eww-session.el ends here