path: root/content-org/emacs.org

#+TITLE: Michał Sapka's Emacs Config
#+AUTHOR: Michał Sapka
#+URL: https://michal.sapka.me
#+STARTUP: show2levels indent logdone

#+HUGO_BASE_DIR: ~/ghq/vcs.sapka.me/michal-sapka-me/
#+HUGO_WEIGHT: auto
#+HUGO_SECTION: emacs


* C-X Emacs                                             :@emacs:
CLOSED: [2023-12-24 Wed 20:00]
:PROPERTIES:
:EXPORT_FILE_NAME: home
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: abstract My little website about Emacs
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: type special
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: hardback true
:EXPORT_HUGO_PAIRED_SHORTCODES: recent-updates st-logo menu
:END:

I am new to Emacs (a little over a year, with a break), so I am in outsider's position.
Most users of Emacs I've met have been using this editor for decades, and since it's not that popular, there are not many noobs out there.
This website is a recording of my findings, as Emacs is a completely different best compared to any other editor I've ever used.

*** Guides

#+attr_shortcode: "emacs-guides" 
#+begin_menu
Guides
#+end_menu

*** Varia

#+attr_shortcode: "emacs-varia" 
#+begin_menu
Varia
#+end_menu

* Guides                                                :@emacs:
:PROPERTIES:
:EXPORT_HUGO_MENU: :menu emacs-guides
:END:
** DONE Input Completiton in Emacs
CLOSED: [2023-05-26 Wed 23:00]
:PROPERTIES:
:EXPORT_FILE_NAME: input-completition-in-emacs
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: abstract Icomplete, IDO and FIDO
:EXPORT_HUGO_MENU: :menu emacs-guides :name "Input completition (Icomplete, IDO, and FIDO)"
:END:
Emacs consists of a massive set of tools with a long history.
Therefore, whatever the problem is, someone likely has already created a package for it.
In many cases, this package is already baked in Emacs.
This is great for veterans but very confusing to newcomers - like me. 

*** The three modes

Emacs comes with three modes for input completion: Icomplete, IDO, and FIDO.
Input completion works with whatever you select in the Minibuffer section.
For text competition, you must use a different solution, like Company mode[fn:company].

The oldest one of those is /icomplete/[fn:icomplete] mode.
It allows you to select from a list of choices incrementally[fn:hist], so you need to type the beginning, and icomplete will narrow the list of propositions.
For example, when searching for "magit", the user needs to type "m" first as omitting it and starting with "i" will instead narrow to options beginning with "i".
Similarly, "mgt" will not limit to "magit" as we're missing"a".
Newer Emacs versions allowallow us to use "flex" matching with icomplete, but more on this later.
Incomplete work for all lists using a mini buffer, like filenames or imenu. 

Then /IDO/[fn:ido] mode (Interactively Do) came in.
It uses the aforementioned "flex" matching, where you can search for any part of the word.
"Magit" would be found with "agit", "mgt" or just "git".
IDO, however, works only with files and buffers, so `M-x` would still fall back to icomplete.

Starting with Emacs 27, we've got /fido/ mode (Fake Ido).
It combines the best things about icomplete (works anywhere) with flex matching.
In fact, all Fido does under the hood is to enable Icomplete with flex matching.

There are also other solutions for competition, not baked into emacs, with the most popular being Helm[fn:helm] and Ivy[fn:ivy].
Personally, I always try the default option, and only if their limits become annoying do I look at the alternatives.
So, I am now a happy FIDO mode user.

[fn:company] [[https://company-mode.github.io/][Company-mode website]]
[fn:hist] According to a [[https://www.reddit.com/r/emacs/comments/13szol7/comment/jltmaud/?utm_source=reddit&utm_medium=web2x&context=3][Reddit comment]] this behavior is relatively new.
Until recently, Icompelete only showed the narrowed selection in a dedicated buffer, similar to using `Tab-Tab` now.
The actual input was still up to the user to type in. Thanks for the tidbit
[fn:icomplete] [[https://www.gnu.org/software/emacs/manual/html_node/emacs/Icomplete.html][Icomplete documentation]]
[fn:ido] [[https://www.gnu.org/software/emacs/manual/html_mono/ido.html][IDO documentation]]
[fn:helm] [[https://emacs-helm.github.io/helm/][Helm website]]
[fn:ivy] [[https://oremacs.com/swiper/][Ivy website]]

*** Using FIDO

To start FIDO mode run

#+BEGIN_SRC emacs-lisp
fido-mode
#+END_SRC

or, if you find a vertical list to be more readable, use

#+BEGIN_SRC emacs-lisp
fido-veritcal-mode
#+END_SRC

You can also customize variables to have it auto-load in your `init.el`:

#+BEGIN_SRC emacs-lisp
(fido-mode t)
;; or
(fido-vertical-mode t)
#+END_SRC

As I've stated above, FIDO is nothing more than flex-enabled Icomplete, so all keybindings work the same.
For vertical mode:

- Typing a string will narrow the selection
- `C-n` and `C-p` will select the next/prev element on the list
- `Tab` will display a buffer with a list of narrowed elements
- `enter` or `C-j` will select the option

One cool thing you can do with FIDO is file deletion (when selecting files) or closing buffers (when selecting buffers) using `C-k`.

*** Customizing the Minibuffer

We can, of course, customize how Icomplete looks works[^savanah].

- /icompleteatches-format/ (default "%s/%s") - how the number of filtered and total options is presented
- /complete-first-match/ (default (t :weight bold)) - how the first filtered option is presented
- /icomplete-selected-match/ (default (t :inherit highlight)) - the same as above, but for vertical mode
- /icomplete-section/ (default (t :inherit shadow :slant italic)) - how the section title for vertical mode is presented
- /icomplete-compute-delay/ (default .15) - how fast the filtering will start after a keypress when a larger number of options is presented
- /icomplete-delay-completions-threshold/ (default 400) - defines the "large number" for icomplete-compute-delay
- /icomplete-max-delay-chars/ (default 2) - maximum number of initial characters before applying /icomplete-compute-delay/. I have no idea what it means, nor have I the knowledge of Elisp to dig into it.
- /icomplete-in-buffer/ (default nil) - enables usage of Icomplete outside of the Minibuffer. I have not tested it.

We can also use /icomplete-minibuffer-setup-hook/ hook if needed.
[^savanah]: list based on [[https://git.savannah.gnu.org/cgit/emacs.git/tree/lisp/icomplete.el][Icomplete source code]]

*** Using Completions from Elisp

The great thing about FIDO is that it, like Icomplete, uses Minibuffer API[fn:minibuffer], so you can simply:

#+BEGIN_SRC emacs-lisp
(completing-read
 "prompt: "
 '(("option1" 1) ("option" 2))
 nil t "default query")
#+END_SRC

[fn:minibuffer] [[https://www.gnu.org/software/emacs/manual/html_node/elisp/Minibuffer-Completion.html][Guide on Minibuffer completition]]
** DONE Moving My RSS Reading to Emacs With Elfeed
CLOSED: [2023-05-19 Wed 23:00]
:PROPERTIES:
:EXPORT_FILE_NAME: moving-my-rss-reading-to-emacs-with-elfeed
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: abstract Setting up config inside an org file
:EXPORT_HUGO_PAIRED_SHORTCODES: img-c
:EXPORT_HUGO_MENU: :menu "emacs-guides" :identifier "elfeed" :name "Following RSS with Elfeed"
:END:
Since Emacs became my shell of choice[fn:1], I am abandoning more and more dedicated applications in favor of different packages.
As it turns out, Emacs packages are very feature rich.
This time: I moved my RSS reading from newsboat[fn:2] to elfeed[fn:3].

Elfeed has very simple keybindings:
- g will refresh the items list
- G will refresh the items list and fetch new items
- r will mark currently selected item is read (remove unread tag)[^4]
- b will open item in the browser


One huge upside of elfeed compared to newsboat is image support.
Emacs is a GUI application, so all images are present in their glory!

#+attr_shortcode: "elfeed-details.png"
#+begin_img-c
Images!
#+end_img-c

My setup is near stock.
I have a few dozen feeds that are auto-tagged.
Three essential tags are "important", "news", and "company".
I want to read each "important", then I want to see all normal, and finally I can just skim "news" and "company".
Adding auto-tagging is very simple: just define the tag when defining the RSS feed list:

#+BEGIN_SRC emacs-lisp
("https://rubenerd.com/feed/" blog important)
("https://www.pine64.org/feed/" company)
#+END_SRC
Now, each new article will be tagged with matching tags.
Elfeed allows to define of custom faces that will be applied to items matching tag[fn:6]:

#+BEGIN_SRC emacs-lisp
(defface important-elfeed-entry
  '((t :foreground "#f77"))
  "Marks an important Elfeed entry."
  :group 'elfeed)
  
(defface nonimportant-elfeed-entry
  '((t :foreground "#C0C0C0"))
  "Marks an nonimportant Elfeed entry."
  :group 'elfeed)

(push '(important important-elfeed-entry)
       elfeed-search-face-alist)
(push '(company nonimportant-elfeed-entry)
      elfeed-search-face-alist)
(push '(news nonimportant-elfeed-entry)
      elfeed-search-face-alist)
#+END_SRC
      

Now important items will be dark red, while company & news will be dark gray

#+attr_shortcode: "elfeed-list.png"
#+begin_img-c
No important things to read at this moment.
#+end_img-c

Elfeed has a few packages expanding its functionality, but I found the default behavior to be exactly right.

[fn:1] [[/2023/emacs-as-a-shell/][Emacs as a Shell]]
[fn:2] [[https://newsboat.org/][Newsboat homepage]]
[fn:3] [[https://github.com/skeeto/elfeed][Elfeed repository on Github]]
[fn:4] The "r" key messes with my muscle memory, as notmuch[^5] uses "ku" for the same action while "r" will start composing a reply.
[fn:5] [[https://d-s.sh/tags/notmuch][Posts tagged about notmuch]]
[fn:6] my elisp-fu not good

** DONE Literate configuration of Elfeed
CLOSED: [2023-06-02 Wed 23:00]
:PROPERTIES:
:EXPORT_FILE_NAME: elfeed-literate-config
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: abstract Setting up config inside an org file
:EXPORT_HUGO_MENU: :menu "emacs-guides" :parent "elfeed" :name "Literate configuration"
:END:
Recently I've been toying with a literate configuration[fn:literate] of Emacs.
My init.el took a straightforward form:

#+BEGIN_SRC emacs-lisp
(org-babel-load-file "~/.emacs.d/config.org")
#+END_SRC

And all of my configuration lives in an org-file.
This alone gives me very little benefit for now, but in the future, it will make it easier to have it as a dedicated page on this site.

However, one thing completely surprised me: the elfeed configuration.
Until now, I used the standard way of configuring feeds with Elisp.
It works, but what it is not is readable.
A list of:

#+BEGIN_SRC emacs-lisp
("https://gideonwolfe.com/index.xml" blog imporant)
("https://fabiensanglard.net/rss.xml" blog important)
("https://protesilaos.com/master.xml" emacs)
#+END_SRC

is far from being manageable and requires constant manual labor.

[fn:literate]: https://en.wikipedia.org/wiki/Literate_programming
*** Elfeed-org

One of the packages expanding capabilities of elfeed is elfeed-org[fn:elf-org].
It allows configuring the list of feeds with a standard org tree.
Since my config is now also an org file, nothing stops me from adding the list as an org-tree inside my config org-file! I set it up via:

{{<highlight lisp "linenos=table,linenostart=199,hl_lines=7">}}
#+BEGIN_SRC org
  ,*** elfeed-org

  ,#+BEGIN_SRC emacs-lisp
  (use-package elfeed-org
    :ensure t
    :config
    (setq rmh-elfeed-org-files (list "~/.emacs.d/config.org"))
    (elfeed-org))
  ,#+END_SRC
#+END_SRC

Therefore, I am now pointing at the same file to become the data source for elfeed-org as the rest of my config.
Just a few lines down, I start to define my list of subscriptions:

#+BEGIN_SRC org
  ,*** Feeds :elfeed:

  ,**** Blogs

  ,***** https://gideonwolfe.com/index.xml      :important:
  ,***** https://fabiensanglard.net/rss.xml.    :important:

  ,**** Emacs

  ,***** https://protesilaos.com/master.xml     :important:
#+END_SRC
Much more readable! Elfeed-org will ignore the entire outer tree and extract the feeds from leaves under the `:elfeed:` tag.
[fn:elf-org]: https://github.com/remyhonig/elfeed-org

** DONE Managing email with Notmuch and Emacs
CLOSED: [2023-07-03 Wed 23:00]
:PROPERTIES:
:EXPORT_FILE_NAME: notmuch
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: abstract My email based workflow for GitHub Pull Review Requests
:EXPORT_HUGO_MENU: :menu emacs-guides :name "Reading and automating email using Notmuch"
:END:
Web email interfaces have taken over the world a long time ago.
Except for Outlook users, only a few people even consider using an actual application for it.
This is one of the primary reasons for our low opinion of electronic mail today, since with limited tools, you get limited capabilities.
While there are options for automatic filtering, tagging, or folding with most clients, those capabilities are barebones. 

Luckily there are still compelling alternatives.

*** Managing email locally
Back in the day of POP, this was the standard: your computer downloaded new messages from the server, and you had local copies from this point.
Then IMAP came, and after it, Exchange.
Now you have a fast and convenient option to sync all changes with other clients and not bother with hard drive space.
But this also puts us at the mercy of email providers.
If a given service doesn't support tags, folders, or saved searches, you cannot use it.
I tried to reverse this direction and never looked back.
I want all my email to be on my machine, available at all times, and accessible instantly.

Mbsync(1)[fn:mbs] is a popular application to populate local ~/Mail folder with remote messages fetched via IMAP.
The config is quite simple. For Gmail[fn:gmail][fn:frosty]:


#+BEGIN_SRC shell -r -n
  MaildirStore gmail-local (ref:local-start)
  Path ~/Mail/gmail/
  Inbox ~/Mail/gmail/INBOX
  Subfolders Verbatim (ref:local-end)

  IMAPStore gmail-remote (ref:remote-start)
  Host imap.gmail.com
  SSLType IMAPS
  AuthMechs LOGIN
  User <username>
  PassCmd <password> (ref:remote-end)

  Channel gmail (ref:chan)
  Far :gmail-remote:
  Near :gmail-local:
  Create Both
  Expunge Both
  Patterns * !"[Gmail]/All Mail" !"[Gmail]/Important" !"[Gmail]/Starred" !"[Gmail]/Bin"
  SyncState *
#+END_SRC

Then type `mbsybc -a`, wait for a few (hundred? depending on the mailbox size) minutes, and voila.
Your `~/Mail/gmail/` is now populated with all your messages. Let's break down the config.

Mbsync(1) assumes two stores exist: local (on your computer) and remote (the IMAP server).
A store is a place where mail exists.
We have then configured in lines [[(local-start)]]-[[(local-end)]] and [[(remote-start)]]-[[(remote-end)]].  

The remote one is self-explanatory.
One thing to remember: some providers will require you to use an app-specific password and reject auth attempts with the normal one.
Our password in line 11 can be either a string with the password or an arbitrary command (think `cat ~/my-secret-password` or a CLI password manager).

The local store is just a definition of local folders to use.
It can be anywhere, but `~/Mail` is the standard, anxd many mail clients will assume that you store your email there.

On line [[(chan)]], we start to define a channel, which is how mbsync(1) works.
One store is `far` (remote), while the other is `near` (on your machine).
The rest of the config defines behavior.
Refer to the manual, but in my case:
- it will create non-matching mailboxes
- it will delete messages in a store if a message was deleted on the other
- it will sync all messages except a few matching the pattern.
- it will store the synchronization state file in the Mail dir.

One last thing to add is a simple cron rule.
You can force mail fetching manually, but I opted for the automatic option.
Therefore, my crontab(1) has:

#+BEGIN_SRC cron
1/5 * * * * killall mbsync &>/dev/null; <msync_dir>/mbsync -a -V 2>&1 > ~/.mbsync_log
#+END_SRC

We will now fetch new messages every 5 minutes.

[fn:mbs] [[https://isync.sourceforge.io/mbsync.html][mbsync on sourceforge]]
[fn:gmail] I have my gripes with Gmail, but it is still the standard.
While this article assumes Gmail, you can easily use mbsync(1) with any IMAP service.
[fn:frosty] Originally I took the config from [[https://frostyx.cz/posts/synchronize-your-2fa-gmail-with-mbsync][Frosty]]

*** Local clients

Now we need to choose a local email client to use.
There is a lot to choose from! Thunderbird[fn:thunderbrid] seems to be the most popular option for GUI users.
For terminal users, we have Mutt(1)[fn:mutt], its successor Neomutt(1)[fn:neomutt], and many, many more.
I used Neomutt(1)[fn:luke] for a while, and it was a pleasure compared to web clients.

However, ever since I started to use Emacs more, I wanted to move my Email inside Emacs.
And to little surprise, we also have a lot to choose from.
By default, Emacs comes with Gnus[fn:gnus], a newsgroups reader with an email client capability.
However, the two most popular packages are Mu4e[fn:mu4e] and notmuch(1)[fn:notmuch]

The last two are based on fast email indexing and searching but assume different workflows.
Mu4e is based on filtering, while notmuch around tagging. 

A friend[fn:alex] recommended Notmuch(1) to me.
I have never tried mu4e as notmuch fully satisfies my needs.

[fn:thunderbrid] [[https://www.thunderbird.net/][Thunderbird website]]
[fn:mutt] [[https://www.mutt.org/][Mutt website]]
[fn:neomutt] [[https://neomutt.org/][Neomutt website]]
[fn:luke] Luke Smith has a few excellent vlogs about Mutt/NeoMutt like [[https://www.youtube.com/watch?v=2jMInHnpNfQ&t=683s)"][Email on the terminal with mutt]]
[fn:gnus] [[https://www.gnu.org/software/emacs/manual/html_node/gnus/][Gnus on gnu.org]]
[fn:mu4e] [[https://www.djcbsoftware.nl/code/mu/][mu4e website]]
[fn:notmuch] [[https://notmuchmail.org/][notmuch website]]
[fn:alex] Thanks, [[https://se30.xyz/][Alex]]

**** Setting up notmuch(1)

Notmuch(1) is not a client but an indexer.
It indexes and tags existing email and allows one to search messages.
It should be present on most systems package management, so install it.
They run `notmuch`, answer a few questions, and you've got yourself a ready notmuch.

Whenever a new mail arrives, it won't be known to notmuch before indexing.
You can manually run `notmuch new` or make a cron definition for it.

One killer feature of notmuch is its sheer speed.
The name comes from the fact that it can work on gigantic mailboxes very swiftly - oh, you have one million messages? That's not much!

Let's try a simple search:

#+BEGIN_SRC shell
$ notmuch search 'from:*@github.com'
#+END_SRC

You can search based on sender, receiver, dates, attachments, contents, titles, etc.
Refer to man pages for `notmuch-search-terms(7)`.
However, to get the most out of notmuch, we need to learn about tags.

Let's add a "gh" tag for messages from Git Hub.

#+BEGIN_SRC shell
$ notmuch search 'from:*@github.com'
$ notmuch tag "+gh" -- "from:@github.com"
#+END_SRC

Now, we can search for such messages

#+BEGIN_SRC shell
$ notmuch search "tag:gh"
#+END_SRC

We can also join multiple search criteria with "and", "or" and other boolean operators.
We now have a fully working local email reader - however we can not send email.
I will not discuss sending email here as it's a separate subject. Notmuch(1) is not for sending email.

Using CLI for reading email is far from pleasant.
All those commands will come in handy, but first, let's add a user interface.

**** Notmuch(1) in Emacs(1)

Notmuch(1) can be used with different UIs, like Mutt(1).
However, it comes with an Emacs(1) package, so let's enable it.

#+BEGIN_SRC emacs-lisp
(use-package notmuch
  :commands notmuch-hello
  :bind (("C-c m" . notmuch-hello)))
#+END_SRC

The key binding "C-c m" is very popular, but you can use whatever you want.

After running `notmuch-hello`, we are not greeted with a list of messages but with a search interface.
You've got access to saved searches, recent searches, and a list of tags.
This tells us that we are dealing with a completely different beast than webmail, and the user needs to think of new workflows.

The way we are thought of thinking of email is a list of messages.
Some clients can mark messages that are more important, favorite, tag them, move them into folders, etc.
But everywhere I know, the primary interface is just a list - unread email on top, read on the bottom.
The behavior I always expect is to open (or mark as read) all incoming messages and then ignore most of them.
If you spent some time on configuration, maybe you have automatic rules - like moving all newsletters to a "newsletter" folder and removing them from your inbox.
Hey[^hey] is even based on separating all incoming messages into three tiers: important mail, newsletters, and paper trial. 
[^hey]: [Hey email website](https://www.hey.com/). It's the best email service I know, but it doesn't allow any external clients, and the pricing is unacceptable for me.

But back to notmuch.
Look at saved searches - we will use them later.
Open "unread," and we see a semi-normal list of messages.
Use "n" and "p" to select email, enter to open it, and so on - standard Emacs stuff.
One thing to remember is that by default, reading an email will not mark it as read.
You need to manually remove the tag via `k u` - either one by one, or on all messages in a selected region (C-spc, it's still a buffer, after all).
"Unread" here is just another tag.
We can be much smarter with marking actionable items.

*** Automatic Github Pull Review workflow

What we've seen before is nothing more than a normal email client with extra steps.
We read emails in Emacs(1), which is great, but we don't get anything extra.
It's time for a real-world example.

I am a software engineer forced to work with GitHub.
One thing I do is to review pull requests.
The primary problem here is knowing that someone wants me to review something.
The review itself is the easy part :-)

I rely solely on email for this information, ostensibly ignoring all nudges on Slack[^slack].
[^slack]: Back when Slack was first sold, it was proposed not only as a chat tool but also as a single place for all information.
We see it now: we connect Slack to everything - GitHub, jira, Data Dog, or pager duty.
The general idea is great, but Slack is a pretty mediocre application.
The only way to manage what you receive is to leave a channel.
But then you lose all other messages sent there, so the price may be high. 

First of all, we need to enable email notifications from GitHub.
Remember to mark that you want to get emails about your own actions.

Now, let's think about what we want to achieve.
For me it is "I want to know about all the pull requests I should look at without opening browser[fn:gh-cli]".
This means I want to see all the review requests I was assigned (personally or by being part of a team) that I have not yet reviewed.
And it can achieve the same.
However, let's ignore it for now, as the same model of email-based dashboards can be expanded to many other things.

Luckily, GitHub allows us to get that from email:
1. When you are first assigned a review, you get a dedicated email
2. When you approve or reject a PR, you get an email
3. When someone asks you to re-review an email, you get the same email as it was the first request for this PR.

We now know that we can use Notmuch(1).
There are two ways: we can use `notmuch-hooks(5)` and place a shell script in `~/Mail/.notmuch/hooks/post-new, but it never worked reliably for me.
Instead, I have a cron job that runs a script:

#+BEGIN_SRC shell -n
#!/usr/bin/env sh

notmuch tag +gh -unread -- '(from:notifications@github.com)'

# Mark new review requests
for thread in $(notmuch search --sort=oldest-first --output=threads -- "\"requested your review on\" and tag:gh and -tag:gh-pr-done"); do
    for msg in $(notmuch search --sort=oldest-first --output=messages -- "$thread"); do
	txt=$(notmuch show "$msg")

	(echo "$txt" | grep "requested your review on") && notmuch tag +gh-pr-todo -- "$thread"
	(echo "$txt" | grep "@michalsapka approved this pull request") && notmuch tag -gh-pr-todo -- "$thread"
	(echo "$txt" | grep "@michalsapka requested changes on this pull request") && notmuch tag -gh-pr-todo -- "$thread"
	(echo "$txt" | grep "Merged.*into") && notmuch tag -gh-pr-todo +gh-pr-done -- "$thread"
    done
done
#+END_SRC

Let's break it down:
1. First, we add a "gh" tag to all notification emails from GitHub and remove the "unread" tag.
   I don't need to be notified about all such emails, but I can still look at the "gh" tag if needed.
2. Then we search for threads where an email informs me about a review request.
   I limit the search to emails from GitHub via the tag from #1 and those without "gh-pr-done" tag. More on the second one in a moment
3. Then I search for all messages in such threads.
   I force order as oldest-first to make it possible to reason about.
   In normal PR, all actions happen with a significant delay between them, so this should be enough not to get lost in the timeframe.
   If I ask for a change in review, the re-request will not happen instantly.
   Note that I get the email body as a variable on line 8.
4. Then comes the meat.
   I will tag the entire thread multiple times based on the body of the message.
   When a request comes, a "gh-pr-todo" is added.
   I need to look at it.
   When I approve or reject a PR, the tag is removed.
   If someone asks for a review, logic from line 10 will be triggered, and the tag will be added again.
   This means that I want to handle all email threads with the "gh-pr-todo" tag.
6. Lastly, when a PR is merged, I ensure that the "gh-pr-todo" tag is removed, and I add the "gh-pr-done" tag so this thread will not be found in step 2 in the future.

There are other ways to tag, like afew(1)[fn:afew], but keeping it to simple shell script working with notmuch(1) directly gives us the greatest amount of freedom and made it easier for me to tell this story.
[fn:afew] [[https://github.com/afewmail/afew][Afew on Github]]
[fn:gh-cli] There is the GitHub CLI which is amazing by itself - one of the best things that GitHub has done in the last few years.

**** Making it more visible

This alone would be a challenge to manage.
An email with a tag would be easily missed.
Notmuch has us covered yet again! My emacs config has a few dedicated lines:

#+BEGIN_SRC emacs-lisp -n
(setq notmuch-search-line-faces
     '(("gh-pr-todo" . ((t :foreground "#f77"))))
     notmuch-saved-searches
     ;; other saved searches omitted
     ( :name "GitHub[reviews]"
       :query "tag:gh-pr-todo"
       :sort-order newest-first))
#+END_SRC

This makes two changes.

1. Firstly, all messages with "gh-pr-todo" will be shown in red in any email list.
   All red items are actionable since we remove this tag in the workflow.
2. Secondly, amongst other saved searches, I have one dedicated to PRs.

With those two things, every time I enter `notmuch-hello` screen, I get instant information about the work I need to do.

**** Making it extra visible

But we can go one step further.
Prot's[fn:prot] excellent notmuch-indicator[fn: not-ind] allows us to add saved searches to the mode line.
After installing it, the configuration is straightforward:

#+BEGIN_SRC emacs-lisp
(notmuch-indicator-mode 1)
(setq notmuch-indicator-refresh-count 60
      notmuch-indicator-hide-empty-counters t
      notmuch-indicator-args
      '((:terms "tag:gh-pr-todo":label "pr:")))
#+END_SRC

This adds a "pr:<count>" to the mode line.
The count is the number of messages, not threads, but frankly, I want it to be 0.
The counter will be refreshed every 60 seconds.
And lastly, if the count is 0, the label will not be added to the mode line.

[fn:prot] [Prot's website](https://protesilaos.com/)
[fn:not-ind] [notmuch-indicator repository](https://git.sr.ht/~protesilaos/notmuch-indicator)

*** The downsides

Notmuch comes with one significant downside: lack of multi-device support.
It's 2023, and most of us have more than one computer and those pesky mobile phones. 

As for the mobile - I have no solution.
The read statuses will sync via mbsync(1), but not much else.
I try to purge myself from phone addiction, so maybe that's a plus?

As for the other computers, we have muchsync(1)[fn:muchsync].
It's an external application designed to sync entire mailboxes and tags between devices over ssh.
I have not tried it yet[fn:boundries], but it looks promising. 

[fn:muchsync] [[https://www.muchsync.org/][Muchsync homepage]]
[fn:boundries] my work computer gets all work messages, and my private one gets all private ones—complete separation. When I get a second personal machine, I will set it up, but for now, there is no use case for me.

*** Summary

With local email and tools like notmuch(1), we are not at the mercy of external tools for even sophisticated workflows. If you get transactional emails, you can extract actionable data. It can be JIRA tickets, Pager Duty alerts, heck - even Amazon deliveries. Here I have demonstrated how easy it is to leverage notmuch(1), simple shell script, and emacs(1) to have a  fully automated notification setup. It does not try to hijack your attention (like mobile notifications do) and is not hidden on some webpage (like GitHub notification), but it still gives actionable results. And all that without leaving the comfort of Emacs. 

One cool thing I plan to apply soon is integrating notmuch(1) with Org-mode with the ol-notmich[oln] package. But for now, I am in the process of moving as many external services to a similar workflow as possible.
[^oln]: [ol-notmuch on sourcehut](https://git.sr.ht/~tarsius/ol-notmuch)

* Varia                                                              :@emacs:
:PROPERTIES:
:EXPORT_HUGO_MENU: :menu emacs-varia
:END:
** DONE Emacs as a Shell
CLOSED: [2023-04-13 Wed 23:00]
:PROPERTIES:
:EXPORT_FILE_NAME: emacs-as-a-shell
:EXPORT_HUGO_CUSTOM_FRONT_MATTER: abstract My current understanding of Emcs
:END:

Pavel Korytov writes in his [[https://sqrtminusone.xyz/posts/2023-04-13-emacs/][recent post]];

#+BEGIN_QUOTE
So over time, Emacs has become my programming environment, email client, window manager, knowledge base, and a lot more. I think I ended up using Emacs for almost as many things as possible;
#+END_QUOTE

This is where I want to be in the near future. So far I've moved my development environment and email to Emacs. Next up are notes, RSS reading, and music listening. 

What I love about Emacs is the consistency between modes/packages. They accomplish widely different things, but the general control scheme is the same. It's great since all TUI programs I use tend to support Vim's way of doing things. Having it all inside Emacs changes the dynamic. I'm trying to think of Emacs as a shell rather than an editor. 

What Emacs really is, is a virtual machine running LISP code. Some say that Emacs violates Linux philosophy. I don't see it this way. Does shell violate it? It's also a way to run different programs. Emacs is an abstraction over real shell which adds some calm to it. It's a way to have an interactive layer over OS... which also does text editing.

So, when you look at it this way, Emacs makes a lot of sense:
- It runs programs. Bigger packages, like Magit, are nothing short of real programs.
- It's scriptable. Elisp all the way!
- It allows for interoperability between programs. 
- It runs above basic OS. You can replace your window manager with Emacs, but you need some sort of kernel.
- You can live entirely inside Emacs, just like you can live entirely inside a terminal. 






* Local vars
# Local Variables:
# org-num-skip-tags: ("UNNUMBERED")
# End: