1;;; url-history.el --- Global history tracking for URL package
2
3;; Copyright (C) 1996, 1997, 1998, 1999, 2004,
4;;   2005, 2006, 2007 Free Software Foundation, Inc.
5
6;; Keywords: comm, data, processes, hypermedia
7
8;; This file is part of GNU Emacs.
9;;
10;; GNU Emacs is free software; you can redistribute it and/or modify
11;; it under the terms of the GNU General Public License as published by
12;; the Free Software Foundation; either version 2, or (at your option)
13;; any later version.
14;;
15;; GNU Emacs is distributed in the hope that it will be useful,
16;; but WITHOUT ANY WARRANTY; without even the implied warranty of
17;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18;; GNU General Public License for more details.
19;;
20;; You should have received a copy of the GNU General Public License
21;; along with GNU Emacs; see the file COPYING.  If not, write to the
22;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
23;; Boston, MA 02110-1301, USA.
24
25;;; Commentary:
26
27;;; Code:
28
29;; This can get a recursive require.
30;;(require 'url)
31(eval-when-compile (require 'cl))
32(require 'url-parse)
33(autoload 'url-do-setup "url")
34
35(defgroup url-history nil
36  "History variables in the URL package."
37  :prefix "url-history"
38  :group 'url)
39
40(defcustom url-history-track nil
41  "*Controls whether to keep a list of all the URLs being visited.
42If non-nil, the URL package will keep track of all the URLs visited.
43If set to t, then the list is saved to disk at the end of each Emacs
44session."
45  :set #'(lambda (var val)
46	   (set-default var val)
47	   (and (bound-and-true-p url-setup-done)
48		(url-history-setup-save-timer)))
49  :type '(choice (const :tag "off" nil)
50		 (const :tag "on" t)
51		 (const :tag "within session" 'session))
52  :group 'url-history)
53
54(defcustom url-history-file nil
55  "*The global history file for the URL package.
56This file contains a list of all the URLs you have visited.  This file
57is parsed at startup and used to provide URL completion."
58  :type '(choice (const :tag "Default" :value nil) file)
59  :group 'url-history)
60
61(defcustom url-history-save-interval 3600
62  "*The number of seconds between automatic saves of the history list.
63Default is 1 hour.  Note that if you change this variable outside of
64the `customize' interface after `url-do-setup' has been run, you need
65to run the `url-history-setup-save-timer' function manually."
66  :set #'(lambda (var val)
67	   (set-default var val)
68	   (if (bound-and-true-p url-setup-done)
69	       (url-history-setup-save-timer)))
70  :type 'integer
71  :group 'url-history)
72
73(defvar url-history-timer nil)
74
75(defvar url-history-changed-since-last-save nil
76  "Whether the history list has changed since the last save operation.")
77
78(defvar url-history-hash-table (make-hash-table :size 31 :test 'equal)
79  "Hash table for global history completion.")
80
81;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
82
83(defun url-history-setup-save-timer ()
84  "Reset the history list timer."
85  (interactive)
86  (ignore-errors
87   (cancel-timer url-history-timer))
88  (setq url-history-timer nil)
89  (if (and (eq url-history-track t) url-history-save-interval)
90      (setq url-history-timer (run-at-time url-history-save-interval
91					   url-history-save-interval
92					   'url-history-save-history))))
93
94(defun url-history-parse-history (&optional fname)
95  "Parse a history file stored in FNAME."
96  ;; Parse out the mosaic global history file for completions, etc.
97  (or fname (setq fname (expand-file-name url-history-file)))
98  (cond
99   ((not (file-exists-p fname))
100    ;; It's completely normal for this file not to exist, so don't complain.
101    ;; (message "%s does not exist." fname)
102    )
103   ((not (file-readable-p fname))
104    (message "%s is unreadable." fname))
105   (t
106    (condition-case nil
107	(load fname nil t)
108      (error (message "Could not load %s" fname))))))
109
110(defun url-history-update-url (url time)
111  (setq url-history-changed-since-last-save t)
112  (puthash (if (vectorp url) (url-recreate-url url) url) time
113           url-history-hash-table))
114
115(defun url-history-save-history (&optional fname)
116  "Write the global history file into `url-history-file'.
117The type of data written is determined by what is in the file to begin
118with.  If the type of storage cannot be determined, then prompt the
119user for what type to save as."
120  (interactive)
121  (or fname (setq fname (expand-file-name url-history-file)))
122  (unless (file-directory-p (file-name-directory fname))
123    (ignore-errors (make-directory (file-name-directory fname))))
124  (cond
125   ((not url-history-changed-since-last-save) nil)
126   ((not (file-writable-p fname))
127    (message "%s is unwritable." fname))
128   (t
129    (let ((make-backup-files nil)
130	  (version-control nil)
131	  (require-final-newline t))
132      (with-current-buffer (get-buffer-create " *url-tmp*")
133	(erase-buffer)
134	(let ((count 0))
135	  (maphash (lambda (key value)
136                     (while (string-match "[\r\n]+" key)
137                       (setq key (concat (substring key 0 (match-beginning 0))
138                                         (substring key (match-end 0) nil))))
139                     (setq count (1+ count))
140                     (insert "(puthash \"" key "\""
141                             (if (not (stringp value)) " '" "")
142                             (prin1-to-string value)
143                             " url-history-hash-table)\n"))
144                   url-history-hash-table)
145          ;; We used to add this in the file, but it just makes the code
146          ;; more complex with no benefit.  Worse: it makes it harder to
147          ;; preserve preexisting history when loading the history file.
148	  ;; (goto-char (point-min))
149	  ;; (insert (format
150	  ;;          "(setq url-history-hash-table (make-hash-table :size %d :test 'equal))\n"
151	  ;;          (/ count 4)))
152	  ;; (goto-char (point-max))
153	  (insert "\n")
154	  (write-file fname))
155	(kill-buffer (current-buffer))))))
156  (setq url-history-changed-since-last-save nil))
157
158(defun url-have-visited-url (url)
159  (url-do-setup)
160  (gethash url url-history-hash-table nil))
161
162(defun url-completion-function (string predicate function)
163  ;; Completion function to complete urls from the history.
164  ;; This is obsolete since we can now pass the hash-table directly as a
165  ;; completion table.
166  (url-do-setup)
167  (cond
168   ((eq function nil)
169    (let ((list nil))
170      (maphash (lambda (key val) (push key list))
171               url-history-hash-table)
172      ;; Not sure why we bother reversing the list.  --Stef
173      (try-completion string (nreverse list) predicate)))
174   ((eq function t)
175    (let ((stub (concat "\\`" (regexp-quote string)))
176	  (retval nil))
177      (maphash
178       (lambda (url time)
179         (if (string-match stub url) (push url retval)))
180       url-history-hash-table)
181      retval))
182   ((eq function 'lambda)
183    (and (gethash string url-history-hash-table) t))
184   (t
185    (error "url-completion-function very confused"))))
186
187(provide 'url-history)
188
189;; arch-tag: fbbbaf63-db36-4e88-bc9f-2939aa93afb2
190;;; url-history.el ends here
191