office: Rename mail module to office module

Reflecting the somewhat expanding scope of the module, renamed it to
office. Still keeps the old files and setups but also got a new README
file.

office/.local/bin/sync-mail

@@ -0,0 +1,166 @@
+#!/usr/bin/env bash
+#
+# Runs mbsync, with pre-hooks and post-hooks
+# by default, the pre-hook first runs imapfilter
+# and afterwards the post-hook indexes with notmuch.
+#
+# At the very least, you will have to set up a gpg
+# encrypted file containing the password for your
+# remote mailbox. It can be set directly below or
+# through the environment variable
+# `MBSYNC_PASSWORD_FILE` and should point to any
+# gpg decryptable file.
+#
+# To run without invoking any hooks or retry attempts,
+# run `checkmail raw`.
+# this will simply invoke a single isync run on all
+# boxes with the correct config file set.
+#
+# To invoke mbsync for a specific group or channel,
+# simply run it with `checkmail <channelname>` and
+# it will only sync the correspondingly named.
+#
+# To run your own commands as hooks overwrite the
+# environment variables `MBSYNC_PRE` and
+# `MBSYNC_POST`. If you want to not have anything run
+# for either of them the easiest way is to set the
+# corresponding environment variable to true.
+# Be careful which commands you put here since they
+# will be evaluated without any special precautions.
+#
+# for more advanced, per-account/channel hooks, see
+# https://sourceforge.net/p/isync/feature-requests/8/
+
+# available env vars:
+# MBSYNC_MAX_TRIES=3
+# MBSYNC_PRE="/bin/usr/cmd-to-run"
+# MBSYNC_POST="/bin/usr/cmd-to-run"
+# MBSYNC_NOTIFY=1
+# MBSYNC_PASSWORD_FILE="/path/to/gpg/file.gpg"
+
+# What to run before and after decrypting the password file.
+PASSWORD_CMD="pass open -t 1min"
+# POST_PASSWORD_CMD=""
+
+prehook() {
+    if [ -n "$MBSYNC_PRE" ]; then
+        eval "$MBSYNC_PRE"
+        return 0
+    fi
+    imapfilter -c "${XDG_CONFIG_HOME:-$HOME/.config}/imapfilter/config.lua"
+}
+
+posthook() {
+    if [ -n "$MBSYNC_POST" ]; then
+        eval "$MBSYNC_POST"
+        return 0
+    fi
+
+    notmuch new 2>/dev/null
+    countnew
+}
+
+# use notmuch to index incoming mail and set the
+# correct number of mails if new ones arrived for notifications
+countnew() {
+    num=$(notmuch count tag:unread and tag:inbox)
+    HASMAIL="${num:-0}"
+}
+
+# fail the routine and optionally send a message why
+fail() {
+    [ -n "$1" ] && echo "$1"
+    exit 1
+}
+
+checkmail() {
+    mbsync -c "${XDG_CONFIG_HOME:-$HOME/.config}/isync/mbsyncrc" "${1:--a}"
+}
+
+checkonline() {
+    # Ping 1.1.1.1 to confirm that we are on the internet
+    ping -c 1 "1.1.1.1" >/dev/null 2>/dev/null || fail "checkmail can not access the internet."
+}
+
+# warn user that he has to enter his password in a moment
+# to stop catching him offguard or entering something by accident
+checkwarnuser() {
+    enablegpgagent
+    if echo "$agt" | grep -qE 'No secret key'; then
+        notify "Mail" "Password phrase needed!"
+        sleep 2.5
+    fi
+}
+
+enablegpgagent() {
+    [ -n "$agt" ] && return
+
+    if [ -n "$PASSWORD_CMD" ]; then
+        IFS=" " read -r -a PASSWORD_CMD <<<"$PASSWORD_CMD"
+        # shellcheck disable=SC2068
+        agt=$(${PASSWORD_CMD[@]})
+    fi
+
+    if [ -n "$POST_PASSWORD_CMD" ]; then
+        IFS=" " read -r -a POST_PASSWORD_CMD <<<"$POST_PASSWORD_CMD"
+        "${POST_PASSWORD_CMD[@]}"
+    fi
+
+    ## exit program after first failed attempt
+    if echo "$agt" | grep -qE 'decryption failed' ||
+        echo "$agt" | grep -qE 'No such file'; then
+        notify "Mail" "Process aborted."
+        exit 1
+    fi
+}
+
+# send out a notification on new mail, to libnotify and stdout
+notify_on_new_mail() {
+    [ "${MBSYNC_NOTIFY:-1}" -eq 0 ] && return
+
+    if [ "${HASMAIL:-0}" -gt 0 ]; then
+        notify "Mail" "New Mail ($HASMAIL)"
+    fi
+}
+
+notify() {
+    command -v notify-send >/dev/null && notify-send "$@"
+    echo "$@"
+}
+
+# Routine start
+
+# check
+
+# skip any retries and pre/post hooks, just run mbsync
+if [ "$1" = "raw" ]; then
+    checkmail
+    exit
+# any other argument passed through selects mbsync targets
+elif [ -n "$1" ]; then
+    selected_mailbox="$1"
+fi
+
+main() {
+    checkwarnuser
+    enablegpgagent
+    prehook
+
+    tries=0
+    while true; do
+        if checkmail "$selected_mailbox"; then
+            break
+        fi
+
+        tries=$((tries + 1))
+        if [ $tries -gt "${MBSYNC_MAX_TRIES:-3}" ]; then
+            fail "maximum retries reached without success."
+        fi
+    done
+    unset tries
+
+    posthook
+    notify_on_new_mail
+}
+
+main