-
Notifications
You must be signed in to change notification settings - Fork 51
/
lui-track.el
152 lines (123 loc) · 5.33 KB
/
lui-track.el
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
;;; lui-track.el --- Provides a bar to track the last read position
;; Copyright (C) 2016, 2019 Vasilij Schneidermann <v.schneidermann@gmail.com>
;; Author: Vasilij Schneidermann <v.schneidermann@gmail.com>
;; This file is part of LUI.
;; 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, write to the Free Software
;; Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
;; 02110-1301 USA
;;; Commentary:
;; This allows you to track where you've last left off a buffer.
;; Use (enable-lui-track) to enable this mode globally. You can
;; customize `lui-track-behavior' to change when the track indicator
;; moves and `lui-track-indicator' to choose between a bar or a fringe
;; indicator. You can also use M-x lui-track-move to move the track
;; indicator manually, and M-x lui-track-jump-to-indicator to move to
;; the line marked by the indicator.
;;; Code:
(require 'lui)
(require 'tracking)
(require 'cl-macs)
(defgroup lui-track nil
"Last read position tracking for LUI"
:prefix "lui-track-"
:group 'lui)
(defcustom lui-track-behavior 'before-switch-to-buffer
"When to move the track bar.
The following values are possible.
before-switch-to-buffer (default)
Move the bar to the bottom of the buffer when switching away
from a buffer.
before-tracking-next-buffer
Move the bar when switching to the next buffer using
\\[tracking-next-buffer].
after-send
Move the bar after sending a message."
:type '(choice (const :tag "Before switching buffers"
before-switch-to-buffer)
(const :tag "Before tracking switch"
before-tracking-next-buffer)
(const :tag "After sending"
after-send))
:group 'lui-track)
(defcustom lui-track-indicator 'bar
"What indicator to use: either a fringe indicator or a full
line to mark last position."
:type '(choice (const :tag "Full bar" bar)
(const :tag "Fringe indicator" fringe))
:group 'lui-track)
(defface lui-track-bar
'((((type graphic) (background light))
:inherit default :extend t :background "dim gray" :height 0.1)
(((type graphic) (background dark))
:inherit default :extend t :background "light gray" :height 0.1)
(((type tty))
:inherit (font-lock-comment-face default) :extend t :underline t))
"Track bar face"
:group 'lui-track)
(defvar lui-track-bar-overlay nil)
(make-variable-buffer-local 'lui-track-bar-overlay)
(defun lui-track--move-pre-input ()
(when (eq lui-track-behavior 'after-send)
(lui-track-move)))
(defun lui-track-move ()
"Move the track indicator down."
(interactive)
(when (derived-mode-p 'lui-mode)
(cl-case lui-track-indicator
(fringe (when (not overlay-arrow-position)
(setq-local overlay-arrow-position (make-marker)))
(set-marker overlay-arrow-position
(marker-position lui-output-marker)))
(bar (when (not lui-track-bar-overlay)
(setq lui-track-bar-overlay
(make-overlay (point-min) (point-min)))
(overlay-put lui-track-bar-overlay 'after-string
(propertize "\n" 'face 'lui-track-bar)))
(move-overlay lui-track-bar-overlay
lui-output-marker lui-output-marker)))))
(defvar lui-track-enabled nil
"Evaluates to t if `enable-lui-track' has been called before.")
(define-advice switch-to-buffer
(:before (buffer-or-name &optional norecord force-same-window) lui-track)
(when (and lui-track-enabled
(eq lui-track-behavior 'before-switch-to-buffer)
;; Do not move the indicator if the buffer is displayed still
(<= (length (get-buffer-window-list (current-buffer)))
1))
(lui-track-move)))
(define-advice tracking-next-buffer
(:before () lui-track)
(when (and lui-track-enabled
(eq lui-track-behavior 'before-tracking-next-buffer))
(lui-track-move)))
;;;###autoload
(defun enable-lui-track ()
"Enable a bar or fringe indicator in Lui buffers that shows
where you stopped reading."
(interactive)
(setq lui-track-enabled t)
(add-hook 'lui-pre-input-hook 'lui-track--move-pre-input))
;;;###autoload
(defun lui-track-jump-to-indicator ()
"Move the point to the first unread line in this buffer.
If point is already there, jump back to the end of the buffer."
(interactive)
(let ((ipos (cl-case lui-track-indicator
(bar (when lui-track-bar-overlay
(overlay-start lui-track-bar-overlay)))
(fringe (when overlay-arrow-position
(marker-position overlay-arrow-position))))))
(cond ((null ipos) (message "No unread messages"))
((= ipos (point)) (goto-char (point-max)))
(t (goto-char ipos)))))
(provide 'lui-track)
;;; lui-track.el ends here