refactor: muttrc configuration source order

Script to source muttrc configuration is preferred as it can choose what
files must exist and not throw extraneous error messages on optional
files. Adding the example configuration files to slim out the readme
from the qusal project, also helps with copying the file from inside
the qube itself instead of having to copy inter-qube.

.reuse/dep5

@@ -7,6 +7,10 @@ Files: files/git/.config/git/message
 Copyright: 2023 Benjamin Grande M. S. <ben.grande.b@gmail.com>
 License: MIT
 
+Files: files/mutt/.config/mutt/sample/*.example
+Copyright: 2024 Benjamin Grande M. S. <ben.grande.b@gmail.com>
+License: GPL-3.0-or-later
+
 Files: files/sh/.config/less/lesskey-old
 Copyright: 2023 Benjamin Grande M. S. <ben.grande.b@gmail.com>
 License: GPL-3.0-or-later

files/mutt/.config/mutt/00_mailbox.muttrc

@@ -23,6 +23,9 @@ set charset           = "utf-8"
 set pager_index_lines = 5
 set my_editor         = "vim -c 'setf mail' "
 set editor            = "$my_editor "
+set mailcap_path      = "~/.mailcap"
+unauto_view *
+auto_view text/plain text/html
 
 ## Composing
 ## Option 'use_envelope_from' does not work reliably, force Message-ID
@@ -46,6 +49,10 @@ set forward_format    = "Fwd: %s"
 set forward_quote
 
 ## Cache
+set spoolfile         = "+INBOX"
+## GMail duplicates sent mails if the 'record' option is set.
+#set record            = "+Sent"
+unset record
 set mbox                = "~/.cache/mutt/archived"
 set record              = "~/.cache/mutt/sent"
 set postponed           = "~/.cache/mutt/postponed"

files/mutt/.config/mutt/00_server.muttrc

@@ -4,7 +4,6 @@
 
 ## IMAP
 set folder            = "imaps://imap.$my_server"
-set spoolfile         = "+INBOX"
 set imap_user         = "$my_user"
 set imap_pass         = "$my_pass"
 set imap_check_subscribed
@@ -20,9 +19,6 @@ set pop_last          = yes
 
 ## SMTP
 set smtp_url          = "smtps://$my_user@smtp.$my_server"
-## GMail duplicates sent mails if the 'record' option is set.
-#set record            = "+Sent"
-unset record
 set smtp_pass         = "$my_pass"
 set realname          = "$my_name"
 set ssl_starttls      = yes

files/mutt/.config/mutt/05_pgp.muttrc

@@ -8,10 +8,9 @@
 
 ## Hooks
 send-hook "~A" "set pgp_autoinline=no"
-send-hook "~t ^security@qubes-os\\.org$" "set pgp_autoinline=yes crypt_autoencrypt=yes"
-send-hook "~t @invisiblethingslab\\.com" "set pgp_autoinline=yes crypt_autoencrypt=yes"
+send-hook "~t ^security@qubes-os\\.org$" "set pgp_autoinline=no crypt_autoencrypt=yes"
+send-hook "~t @invisiblethingslab\\.com" "set pgp_autoinline=no crypt_autoencrypt=yes"
 send-hook "~t @googlegroups\\.com" "set pgp_autoinline=yes crypt_autoencrypt=no"
-send-hook "~t $from" "set pgp_autoinline=yes"
 
 ## General Encryption and Signature
 set crypt_autopgp            = yes # Use PGP for encryption

files/mutt/.config/mutt/muttrc

@@ -2,14 +2,7 @@
 ##
 ## SPDX-License-Identifier: AGPL-3.0-or-later
 
-## Source configuration
+## Source all configurations
 cd ~/.config/mutt
-source ~/.muttrc-credentials.local
-source server.muttrc
-source mailbox.muttrc
-source pgp.muttrc
-source bindings.muttrc
-source colors.muttrc
-source ~/.muttrc-aliases.local
-source ~/.muttrc.local
+source mutt-sorcerer|
 ## vim: ft=muttrc

files/mutt/.config/mutt/sample/muttrc-aliases.local.example

@@ -0,0 +1,4 @@
+## Copy to ~/.muttrc-aliases.local and modify.
+## Optional configuration.
+
+alias qubes-devel <qubes-devel@googlegroups.com>

files/mutt/.config/mutt/sample/muttrc-credentials.local.example

@@ -0,0 +1,12 @@
+## Copy to ~/.muttrc-credentials.local and modify.
+## Mandatory configuration.
+## First file to be sourced: defines variables to be referenced by other files.
+
+set pgp_default_key = "0x1234567890ABCDEF"
+set pgp_sign_as     = "0x1234567890ABCDEF"
+set my_name         = "Bilbo Baggins"
+set my_user         = "bilbo"
+set my_server       = "shire.org"
+
+## Password is unnecessary if Mutt is permanently offline.
+set my_pass         = "mypassword"

files/mutt/.config/mutt/sample/muttrc.local.example

@@ -0,0 +1,8 @@
+## Copy to ~/.muttrc.local and modify.
+## Optional configuration.
+## Last file to be source: overrides previous definitions.
+
+lists .*@googlegroups\\.com
+subscribe qubes-(announce|devel)@googlegroups\\.com
+fcc-save-hook qubes-announce@googlegroups\\.com =list/qubes-announce/
+fcc-save-hook qubes-devel@googlegroups\\.com =list/qubes-devel/

files/mutt/.config/mutt/sample/offline.muttrc.example

@@ -0,0 +1,19 @@
+## Copy to ~/.config/mutt/offline.muttrc and modify.
+
+## SPDX-FileCopyrightText: 2023 Benjamin Grande M. S. <ben.grande.b@gmail.com>
+##
+## SPDX-License-Identifier: AGPL-3.0-or-later
+
+set read_only     = yes
+
+unset spoolfile
+unset folder
+unset smtp_url
+set imap_passive  = yes
+
+set sendmail      = "env EMAIL_CONN_TEST=x /usr/libexec/msmtp/msmtpq/msmtpq"
+set sendmail_wait = 0
+set folder        = "~/mail"
+set spoolfile     = "+INBOX"
+
+## vim: ft=muttrc

files/mutt/.config/mutt/sample/signature.example

@@ -0,0 +1,4 @@
+## Copy to ~/.signature and modify, including deleting all commends.
+## Optional configuration.
+Regards,
+John Doe

files/mutt/.local/bin/mutt-sorcerer

@@ -0,0 +1,35 @@
+#!/bin/sh
+##
+## SPDX-FileCopyrightText: 2023 Benjamin Grande M. S. <ben.grande.b@gmail.com>
+##
+## SPDX-License-Identifier: AGPL-3.0-or-later
+##
+## Mutt Sorcerer - source Mutt configuration like a wizard
+## Useful if some configurations files in non-default locations might exist.
+
+set -eu
+
+credentials_file="${HOME}/.muttrc-credentials.local"
+aliases_file="${HOME}/.muttrc-aliases.local"
+local_file="${HOME}/.muttrc.local"
+
+## source_redable(): do not require that the file exists in the first place.
+source_existent(){
+  for file in "${@}"; do
+    if test -f "${file}"; then
+      echo source "\"${file}\""
+    fi
+  done
+  unset file
+}
+
+## Source files that must exist, let mutt fail otherwise.
+echo source "\"${credentials_file}\""
+
+## PWD is inherited from the muttrc that called this script.
+for file in *.muttrc; do
+  echo source "\"${file}\""
+done
+unset file
+
+source_existent "${aliases_file}" "${local_file}"