#!/bin/bash
# Copyright (C) 2019 Ian Kelling
# SPDX-License-Identifier: AGPL-3.0-or-later

# usage: runs 4 times every 15 seconds unless any args are passed, or we
# are on battery power, then just runs once.

if [ -z "$BASH_VERSION" ]; then echo "error: shell is not bash" >&2; exit 1; fi

source /a/bin/errhandle/err
status_file=/dev/shm/iank-status

shopt -s nullglob
shopt -s dotglob
shopt -s extglob

for p in ~/.gem/ruby/*/bin; do
  PATH="$PATH:$p"
done


verbose=false
if [[ $1 ]]; then
  verbose=true
fi
v() {
  if $verbose; then
    printf "%s\n" "$*"
  fi
}
# log-once COUNT NAME [MESSAGE]
lo() {
  /usr/local/bin/log-once "$@" | ifne mail -s "$HOSTNAME: system-status $2" root@localhost
}

write-status() {
  chars=("${first_chars[@]}")

  # clock us out in timetrap if are idle too long
  if [[ -e /p/.timetrap.db ]]; then
    export DISPLAY=:0
    if type -p xprintidle &>/dev/null && xidle=$(xprintidle 2>/dev/null); then
      if [[ $xidle == [0-9]* ]]; then
        sheet=$(sqlite3 /p/.timetrap.db "select sheet from entries where end is NULL;")
        idle=300000
        if [[ $sheet == w ]]; then
          idle=900000
        fi
        if [[ $sheet && $xidle -gt $idle ]]; then
          timetrap out
        fi
      fi
    fi
  fi

  if pgrep -f 'emacs --daemon' &>/dev/null; then
    emacsfiles="$(emacsclient --eval "$(cat /a/bin/ds/unsaved-buffers.el)"| sed '/^"nil"$/d;s/^"(/E: /;s/)"$//')"
    if [[ $emacsfiles ]]; then
      chars+=("$emacsfiles")
    fi
  fi

  glob=(/nocow/btrfs-stale/*)
  if [[ -e ${glob[0]} ]]; then
    chars+=("STALE")
  fi
  if [[ $(find /var/mail -type f \! -empty -print -quit) ]]; then
    var_mail_msg="message in /var/mail"
  fi
  lo -1 var_mail $var_mail_msg
  glob=(/m/md/bounces/new/*)
  if [[ -e ${glob[0]} ]]; then
    chars+=("BOUNCE")
    bouncemsg="message in /m/md/bounces/new"
  fi
  lo -1 bounce $bouncemsg
  # emails without the S (seen) flag. this only checks the last flag,
  # but its good enough for me.
  glob=(/m/md/alerts/{new,cur}/!(*,S))
  if [[ -e ${glob[0]} ]]; then
    chars+=("A")
  fi
  tmp=(/var/local/cron-errors/mailtest-check*)
  if (( ${#tmp[@]} )); then
    chars+=("MAILPING")
  fi
  tmp=(/var/local/cron-errors/mailtest-slow*)
  if (( ${#tmp[@]} )); then
    chars+=("SPAMD")
  fi

  # early in install process, we dont have permission yet for exiqgrep
  qlen=$(/usr/sbin/exiqgrep -o 600 -c -b | awk '{print $1}') ||:
  if ((qlen)); then
    qmsg="queue length $qlen"
    chars+=("q $qlen")
  fi
  case $HOSTNAME in
    # No point in emailing about the mailq on a host where we don't
    # check email.
    $MAIL_HOST|bk)
      lo -120 qlen $qmsg
      ;;
  esac

  begin=false
  if ! make -C /b/ds -q ~/.local/distro-begin || [[ $(<~/.local/distro-begin) != 0 ]]; then
    begin=true
  fi

  end=false
  if ! make -C /b/ds -q ~/.local/distro-end || [[ $(<~/.local/distro-end) != 0 ]]; then
    end=true
  fi

  # these conditions are so we dont have an overly verbose prompt
  if $begin && $end; then
    chars+=("D")
  elif $begin; then
    chars+=("DB")
  elif $end; then
    chars+=("DE")
  else
    f=~/.local/conflink
    # shellcheck disable=SC2043
    for _ in 1; do
      if [[ -e $f ]]; then
        now=$(date +%s)
        fsec=$(stat -c%Y $f)
        # the / 60 makes it 0-59 seconds less strict, +1 to help make sure we
        # dont have any false positives.
        fmin=$(( (fsec - now + 1 ) / 60 ))
        fminplus=$(( fmin + 60*24 ))
        # Filesystem files get copied, so find any newer than the last run.
        # The rest are hueristics:
        # Given the last time we added a file in git, is that newer than the last conflink run.
        # Given new files not added to git, were they modified more recently than the last conflink? but,
        # push their modification time back by a day so we can develop them before needing to add them to git.

        all_dirs=({/a/bin/ds,/p/c}{/filesystem,/machine_specific/$HOSTNAME/filesystem})
        # This part is copied from conflink
        for x in /p/c/machine_specific/*.hosts /a/bin/ds/machine_specific/*.hosts; do
          if grep -qxF $HOSTNAME $x; then all_dirs+=( ${x%.hosts} ); fi
        done

        # Just because i forget a lot, -mmin -NUM means files modified <= NUM minutes ago
        if (( fmin < 0 )) && [[ $(find ${all_dirs[@]} -mmin $fmin -type f -print -quit 2>/dev/null) ]]; then
          v conflink newer filesystem files
          chars+=("CONFLINK")
          break
        fi

        for d in /a/bin/distro-setup /p/c; do
          cd $d
          if [[ ! -e .git ]]; then
            # some hosts i dont push all of /p/c
            continue
          fi
          if (( $(date -d "$(git log --diff-filter=ACR --format=%aD -1)" +%s) > fsec )); then
            v conflink: newer files checked in to git
            chars+=("CONFLINK")
            break
          fi

          untracked=()
          while read -r l; do
            untracked+=("$l")
          done < <(git ls-files -o --exclude-standard)
          if [[ ${untracked[0]} && $(find "${untracked[@]}" -mmin $fminplus -type f -print -quit) ]]; then
            v conflink: untracked in $d
            chars+=("CONFLINK")
            break
          fi
        done
        cd /

      fi
      if [[ ! -e $f || $(<$f) != 0 ]]; then
        v conflink: last run not found or failed
        chars+=("CONFLINK")
        break
      fi
    done
  fi

  if [[ -s /var/log/exim4/paniclog ]]; then
    chars+=("PANIC!")
    # leave it up to epanic-clean to send email notification
  fi

  source /a/bin/bash_unpublished/source-state
  if [[ $MAIL_HOST == "$HOSTNAME" ]]; then
    bbkmsg=
    if [[ $(systemctl is-active btrbk.timer) != active ]]; then
      chars+=("BTRBK.TIMER")
      bbkmsg="btrbk.timer not enabled"
    fi
    lo -960 btrbk.timer $bbkmsg

    ## check if last snapshot was within an hour
    vol=o
    # this section generally copied from btrbk scripts, but
    # this part modified to speed things up by about half a second.
    # I'm not sure if its quite as reliable, but it looks pretty safe.
    # Profiled it using time and also adding to the top of the file:
    # set -x
    # PS4='+ $(date "+%2N") '
    # allow failure in case there are no snapshots yet.
    # shellcheck disable=SC2012
    shopt -u nullglob
    files=(/mnt/root/btrbk/$vol.20*)
    shopt -s nullglob
    snaps=()
    if (( ${#files[@]} )); then
      snaps=($(ls -1avdr "${files[@]}" 2>/dev/null |head -n1 || : ))
    fi
    now=$(date +%s)
    maxtime=0
    for s in ${snaps[@]}; do
      file=${s##*/}
      t=$(date -d $(sed -r  's/(.{4})(..)(.{5})(..)(.*)/\1-\2-\3:\4:\5/' <<<${file#$vol.}) +%s)
      if (( t > maxtime )); then
        maxtime=$t
      fi
    done
    if (( maxtime < now - 4*60*60 )); then
      chars+=("OLD-SNAP")
      snapshotmsg="/o snapshot older than 4 hours"
    fi
    lo -1 old-snapshot $snapshotmsg
  fi

  cat /a/bin/bash_unpublished/source-state >$status_file

  if [[ ${chars[*]} ]]; then
    echo "ps_char=\"${chars[*]} \$ps_char\"" >>$status_file
  fi

}
# use this if we want to do something just once per minute
first_chars=()

power=true
if [[ -e /sys/class/power_supply/AC/online && $(</sys/class/power_supply/AC/online) == 0 ]]; then
  power=false
fi

write-status
if [[ $1 ]]; then
  cat $status_file
  exit 0
fi

if ! $power; then
  exit 0
fi

# about 15 minutes
for ((i=1; i<=60; i++)); do
  sleep 15
  write-status
done