#+title: TMR May Ring
#+author: Protesilaos Stavrou
#+email: info@protesilaos.com
#+language: en
#+options: ':t toc:nil author:t email:t num:t
#+startup: content

#+macro: stable-version 0.2.0
#+macro: release-date 2022-04-21
#+macro: development-version 0.3.0-dev
#+macro: file @@texinfo:@file{@@$1@@texinfo:}@@
#+macro: space @@texinfo:@: @@
#+macro: kbd @@texinfo:@kbd{@@$1@@texinfo:}@@

#+export_file_name: tmr.texi

#+texinfo_filename: tmr.info
#+texinfo_dir_category: Emacs misc features
#+texinfo_dir_title: TMR May Ring: (tmr)
#+texinfo_dir_desc: Set timers using a convenient notation
#+texinfo_header: @set MAINTAINERSITE @uref{https://protesilaos.com,maintainer webpage}
#+texinfo_header: @set MAINTAINER Protesilaos Stavrou
#+texinfo_header: @set MAINTAINEREMAIL @email{info@protesilaos.com}
#+texinfo_header: @set MAINTAINERCONTACT @uref{mailto:info@protesilaos.com,contact the maintainer}

This manual, written by Protesilaos Stavrou, describes the customization
options for =tmr= (or =tmr.el=, tmr, TMR, TMR May Ring, ...), and
provides every other piece of information pertinent to it.

The documentation furnished herein corresponds to stable version
{{{stable-version}}}, released on {{{release-date}}}.  Any reference to
a newer feature which does not yet form part of the latest tagged
commit, is explicitly marked as such.

Current development target is {{{development-version}}}.

+ Homepage: https://protesilaos.com/emacs/tmr.
+ Git repository: https://git.sr.ht/~protesilaos/tmr.
+ Mailing list: https://lists.sr.ht/~protesilaos/tmr.

#+toc: headlines 8 insert TOC here, with eight headline levels

* COPYING
:PROPERTIES:
:CUSTOM_ID: h:c002f811-ea06-4123-988b-a73183581fb9
:END:

Copyright (C) 2021-2022  Free Software Foundation, Inc.

#+begin_quote
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.3 or
any later version published by the Free Software Foundation; with no
Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and
with the Back-Cover Texts as in (a) below.  A copy of the license is
included in the section entitled “GNU Free Documentation License.”

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and
modify this GNU manual.”
#+end_quote

* Overview
:PROPERTIES:
:CUSTOM_ID: h:7b3966d3-43c6-47f1-816a-8104f634bbd1
:END:
#+cindex: Overview of features

#+findex: tmr
TMR is an Emacs package that provides facilities for setting timers
using a convenient notation.  The first point of entry is the ~tmr~
command.  It prompts for a unit of time, which is represented as a
string that consists of a number and, optionally, a single character
suffix which specifies the unit of time.  Without a suffix, the number
is interpreted as a count in minutes.  Valid input formats:

| Input | Meaning   |
|-------+-----------|
| 5     | 5 minutes |
| 5m    | 5 minutes |
| 5s    | 5 seconds |
| 5h    | 5 hours   |

The input can be a floating point:

| Input | Meaning                  |
|-------+--------------------------|
| 1.5   | 1.5 minutes (90 seconds) |
| 1.5h  | 1.5 hours (90 minutes)   |

#+vindex: tmr-descriptions-list
If ~tmr~ is called with an optional prefix argument (=C-u=), it asks for
a description to accompany the given timer.  Preconfigured candidates
are specified in the user option ~tmr-descriptions-list~, though any
arbitrary input is acceptable at the minibuffer prompt.

#+findex: tmr-with-description
An alternative to the ~tmr~ command is ~tmr-with-description~.  The
difference between the two is that the latter always prompts for a
description.

When the timer is set, a message is sent to the echo area recording the
current time and the point in the future when the timer elapses.  Echo
area messages can be reviewed with the ~view-echo-area-messages~ which
is bound to =C-h e= by default.  To check all timers, use the command
~tmr-tabulated-view~ ([[#h:51fe78e0-d614-492b-b7a3-fb6d5bd52a9a][About tmr-tabulated]]).

[ The following are part of {{{development-version}}}. ]

#+findex: tmr-cancel
The ~tmr-cancel~ command is used to cancel running timers (as set by the
~tmr~ or ~tmr-with-description~ commands).  If there is only one timer,
it cancels it outright.  If there are multiple running timers, it
produces a minibuffer completion prompt which asks for one among them.
Timers at the completion prompt are described by the exact time they
were set and the input that was used to create them, including the
optional description that ~tmr~ and ~tmr-with-description~ accept.

#+findex: tmr-clone
A timer can be cloned with the ~tmr-clone~ command.  It directly copies
the duration and optional description of a timer into a new one.  With
an optional prefix argument, this command prompts for a duration and, if
the underlying timer had a description, for a description as well.  The
default values of such prompts as those of the original timer.

Timers have hooks associated with their creation, cancellation, or
completion ([[#h:c908f440-da08-462e-be4e-a61fb274ecbc][Hooks]]).  TMR can also integrate with the desktop environment
to send notifications ([[#h:56bbbd6f-5b63-4375-9c86-e1eb231be356][Sound and desktop notifications]]).

** About tmr-tabulated
:PROPERTIES:
:CUSTOM_ID: h:51fe78e0-d614-492b-b7a3-fb6d5bd52a9a
:END:
#+cindex: About tmr-tabulated and relevant commands

[ Part of {{{development-version}}}. ]

#+findex: tmr-tabulated-view
Active timers can be viewed in a grid with ~tmr-tabulated-view~ (part of
the =tmr-tabulated.el= file).  The grid is placed in the
=*tmr-tabulated-view*= buffer and looks like this:

#+begin_example
Start      End        Finished?  Description
12:26:50   12:51:50   ✔         Update tmr manual
12:26:35   12:56:35              Bake bread
12:26:26   12:36:26              Prepare tea
#+end_example

If a timer has elapsed, it has a check mark associated with it,
otherwise the =Finished?= column is empty.  A =Description= is shown
only if it is provided while setting the timer, otherwise the field is
left blank.

The ~tmr-tabulated-view~ command relies on Emacs' ~tabulated-list-mode~.
From the =*tmr-tabulated-view*= buffer, invoke the command
~describe-mode~ to learn about the generic applicable key bindings, such
as how to expand/contract columns and toggle their sort.

While in this grid view, one can perform several operations on timers:

+ The =+= key creates a new timer by calling the standard ~tmr~ command.
  As always, use a prefix argument to also prompt for a description.

#+findex: tmr-tabulated-clone
+ The =c= key invokes the ~tmr-tabulated-clone~ command.  It is the same
  as ~tmr-clone~ plus some tweaks for the grid view.

#+findex: tmr-tabulated-cancel
+ The =k= key runs the ~tmr-tabulated-cancel~ command.  It immediately
  cancels the timer at point.

#+findex: tmr-tabulated-reschedule
+ The =s= key runs the ~tmr-tabulated-reschedule~ command.  It
  effectively replaces the timer at point with a new one, using the
  aforementioned "cancel" and "clone" operations.  If the timer being
  rescheduled has a description, this command will also prompt for a
  description while creating the new timer, otherwise it will just ask
  for a duration.

#+findex: tmr-tabulated-rewrite-description
+ The =w= key invokes the ~tmr-tabulated-rewrite-description~ command.
  It prompts for user input and uses it to rewrite the description of
  the timer at point.

** Hooks
:PROPERTIES:
:CUSTOM_ID: h:c908f440-da08-462e-be4e-a61fb274ecbc
:END:
#+cindex: Hooks triggered by timer operations

TMR provides the following hooks:

#+vindex: tmr-timer-created-functions
+ ~tmr-timer-created-functions~ :: This is triggered by the ~tmr~
  command.  By default, it will print a message in the echo area showing
  the newly created timer's start and end time as well as its optional
  description (if provided).

#+vindex: tmr-timer-completed-functions
+ ~tmr-timer-completed-functions~ :: This runs when a timer elapses.  By
  default, it will (i) produce a desktop notification which describes
  the timers start/end time and optional description (if available),
  (ii) play an alarm sound ([[#h:56bbbd6f-5b63-4375-9c86-e1eb231be356][Sound and desktop notifications]]), and (iii)
  print a message in the echo area which is basically the same as the
  desktop notification.

#+vindex: tmr-timer-cancelled-functions
+ ~tmr-timer-cancelled-functions~ :: This is called by ~tmr-cancel~.  By
  default, it will print a message in the echo area describing the timer
  that was cancelled.

** Sound and desktop notifications
:PROPERTIES:
:CUSTOM_ID: h:56bbbd6f-5b63-4375-9c86-e1eb231be356
:END:
#+cindex: Alarm sound and settings for desktop notifications

#+vindex: tmr-sound-file
#+vindex: tmr-notification-urgency
Once the timer runs its course, it produces a desktop notification and
plays an alarm sound.  The notification's message is practically the
same as that which is sent to the echo area.

The sound file for the alarm is defined in ~tmr-sound-file~, while the
urgency of the notification can be set through the user option
~tmr-notification-urgency~.  Note that it is up to the desktop
environment or notification daemon to decide how to handle the urgency
value.

If the ~tmr-sound-file~ is nil, or the file is not found, no sound will
be played.

Sound playback depends on the =ffplay= executable which is part of
=ffmpeg=.

* Installation
:PROPERTIES:
:CUSTOM_ID: h:46378bdf-f6cc-469e-b0b0-1b90dd9aa595
:END:
#+cindex: Installation instructions

** GNU ELPA package
:PROPERTIES:
:CUSTOM_ID: h:807c2a8c-3d49-4fb3-bfb9-84d10675c95b
:END:

The package is available as =tmr=.  Simply do:

: M-x package-refresh-contents
: M-x package-install

And search for it.

** Manual installation
:PROPERTIES:
:CUSTOM_ID: h:39fae83f-a49a-4887-8132-eb42e61919ea
:END:

Assuming your Emacs files are found in =~/.emacs.d/=, execute the
following commands in a shell prompt:

#+begin_src sh
cd ~/.emacs.d

# Create a directory for manually-installed packages
mkdir manual-packages

# Go to the new directory
cd manual-packages

# Clone this repo, naming it "tmr"
git clone https://git.sr.ht/~protesilaos/tmr tmr
#+end_src

Finally, in your =init.el= (or equivalent) evaluate this:

#+begin_src emacs-lisp
;; Make Elisp files in that directory available to the user.
(add-to-list 'load-path "~/.emacs.d/manual-packages/tmr")
#+end_src

Everything is in place to set up the package.

* Sample configuration
:PROPERTIES:
:CUSTOM_ID: h:69eeb3fb-f11d-431e-ae16-2d9b322871cc
:END:
#+cindex: Package configuration

#+begin_src emacs-lisp
;; Load the `tmr' library
(require 'tmr)

;; set to nil to disable the sound
(setq tmr-sound-file
      "/usr/share/sounds/freedesktop/stereo/alarm-clock-elapsed.oga")

(setq tmr-notification-urgency 'normal)
(setq tmr-descriptions-list (list "Boil water" "Prepare tea" "Bake bread"))

;; OPTIONALLY set global key bindings:
(let ((map global-map))
  (define-key map (kbd "C-c t t") #'tmr)
  (define-key map (kbd "C-c t T") #'tmr-with-description)
  (define-key map (kbd "C-c t l") #'tmr-tabulated-view) ; "list timers" mnemonic
  (define-key map (kbd "C-c t c") #'tmr-clone)
  (define-key map (kbd "C-c t k") #'tmr-cancel))
#+end_src

* Acknowledgements
:PROPERTIES:
:CUSTOM_ID: h:047ecc52-ca02-4424-a037-c5b6a02383de
:END:
#+cindex: Contributors

TMR is meant to be a collective effort.  Every bit of help matters.

+ Authors :: Protesilaos Stavrou (maintainer), Damien Cassou.

+ Contributions to the code or manual :: Christian Tietze, Damien
  Cassou.

* GNU Free Documentation License
:PROPERTIES:
:CUSTOM_ID: h:b8b7def2-5ab0-4623-b3ef-2a1bd17bb42a
:END:

#+texinfo: @include doclicense.texi

#+begin_export html
<pre>

                GNU Free Documentation License
                 Version 1.3, 3 November 2008


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translation of this License, and all the license notices in the
Document, and any Warranty Disclaimers, provided that you also include
the original English version of this License and the original versions
of those notices and disclaimers.  In case of a disagreement between
the translation and the original version of this License or a notice
or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements",
"Dedications", or "History", the requirement (section 4) to Preserve
its Title (section 1) will typically require changing the actual
title.


9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense, or distribute it is void, and
will automatically terminate your rights under this License.

However, if you cease all violation of this License, then your license
from a particular copyright holder is reinstated (a) provisionally,
unless and until the copyright holder explicitly and finally
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Moreover, your license from a particular copyright holder is
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Termination of your rights under this section does not terminate the
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10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the
GNU Free Documentation License from time to time.  Such new versions
will be similar in spirit to the present version, but may differ in
detail to address new problems or concerns.  See
https://www.gnu.org/licenses/.

Each version of the License is given a distinguishing version number.
If the Document specifies that a particular numbered version of this
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of any later version that has been published (not as a draft) by the
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11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any
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"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0
license published by Creative Commons Corporation, a not-for-profit
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"Incorporate" means to publish or republish a Document, in whole or in
part, as part of another Document.

An MMC is "eligible for relicensing" if it is licensed under this
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The operator of an MMC Site may republish an MMC contained in the site
under CC-BY-SA on the same site at any time before August 1, 2009,
provided the MMC is eligible for relicensing.


ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of
the License in the document and put the following copyright and
license notices just after the title page:

    Copyright (c)  YEAR  YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.3
    or any later version published by the Free Software Foundation;
    with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
    A copy of the license is included in the section entitled "GNU
    Free Documentation License".

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this:

    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other
combination of the three, merge those two alternatives to suit the
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If your document contains nontrivial examples of program code, we
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to permit their use in free software.
</pre>
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