#!/bin/bash
# I, Ian Kelling, follow the GNU license recommendations at
# https://www.gnu.org/licenses/license-recommendations.en.html. They
# recommend that small programs, < 300 lines, be licensed under the
# Apache License 2.0. This file contains or is part of one or more small
# programs. If a small program grows beyond 300 lines, I plan to switch
# its license to GPL.

# Copyright 2024 Ian Kelling

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at

#     http://www.apache.org/licenses/LICENSE-2.0

# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# basic yum/apt package manager abstraction, plus a few minor conveniences
if command -v yum &> /dev/null; then
  # package manager
  p() {
    local s; [[ $EUID != 0 ]] && s=sudo
    $s yum "$@"
  }
  # package install
  pi() {
    local s; [[ $EUID != 0 ]] && s=sudo
    $s yum -y install "$@"
  }
  # package find
  pfd() {
    local s; [[ $EUID != 0 ]] && s=sudo
    $s yum search "$@"
  }
  # package remove/uninstall
  pu() {
    local s; [[ $EUID != 0 ]] && s=sudo
    $s yum autoremove "$@"
  }
  # shellcheck disable=SC2120
  pup() { # upgrade
    local s; [[ $EUID != 0 ]] && s=sudo
    $s yum -y distro-sync full "$@"
  }
  # package list info
  pl() {
    yum info "$@"
  }
  pfile() {
    yum whatprovides \*/$1
  }

elif command -v apt-get &>/dev/null; then
  plock-wait() {
    local i
    i=0
    while fuser /var/lib/dpkg/lock &>/dev/null; do
      sleep 1
      i=$(( i+1 ))
      if (( i > 300 )); then
        echo "error: timed out waiting for /var/lib/dpkg/lock" >&2
        return 1
      fi
    done
  }
  pcheck() {
    for arg; do
      if [[ $1 == -* ]]; then
        shift
      else
        break
      fi
    done
    if dpkg -s -- "$@" |& grep -Fx "Status: install ok installed" &>/dev/null; then
      return 1
    fi
    return 0
  }
  pp() { # package policy
    apt-cache policy $@
  }
  p() {
    local s; [[ $EUID != 0 ]] && s=sudo
    case $1 in
      install)
        $s apt-get --purge --auto-remove "$@"
        ;;
      *)
        $s apt-get "$@"
        ;;
    esac
  }
  pupdate() {
    local now t s f cachetime limittime; [[ $EUID != 0 ]] && s=sudo
    # update package list if its more than an 2 hours old
    f=/var/cache/apt/pkgcache.bin
    if [[ -r $f ]]; then
      cachetime=$(stat -c %Y $f )
    else
      cachetime=0
    fi
    now=$(date +%s)
    limittime=$(( now - 60*60*2 ))
    for f in /etc/apt/sources.list /etc/apt/sources.list.d/*.list; do
      if [[ -r $f ]]; then
        t=$(stat  -c %Y $f )
        if (( t > limittime )); then
          limittime=$t
        fi
      fi
    done
    if (( cachetime > limittime )); then
      $s apt-get update
    fi
  }
  pi() {
    pcheck "$@" || return 0
    pupdate
    if [[ $- != *i* ]]; then
      echo pi "$*"
    fi
    if [[ $EUID == 0 ]]; then
      DEBIAN_FRONTEND=noninteractive apt-get -y install --purge --auto-remove "$@"
    else
      sudo DEBIAN_FRONTEND=noninteractive apt-get -y install --purge --auto-remove "$@"
    fi

  }

  pi-nostart() {
    local ret=
    pcheck "$@" || return 0
    plock-wait
    pupdate
    local f=/usr/sbin/policy-rc.d
    if [[ $- != *i* ]]; then
      echo pi-nostart "$@"
    fi
    if [[ $EUID == 0 ]]; then
      dd of=$f status=none <<EOF
#!/bin/sh
exit 101
EOF
      chmod +x $f
      DEBIAN_FRONTEND=noninteractive apt-get -y install --purge --auto-remove "$@" || ret=$?
      rm $f
    else
      sudo dd of=$f status=none <<EOF
#!/bin/sh
exit 101
EOF
      sudo chmod +x $f
      sudo DEBIAN_FRONTEND=noninteractive apt-get -y install --purge --auto-remove "$@" || ret=$?
      sudo rm $f
    fi
    return $ret
  }
  # package find description
  pfd() {
    # package name and descriptions
    apt-cache search "$@"
  }
  # package find file
  pff() {
    local s; [[ $EUID != 0 ]] && s=sudo
    # nice aptitude search from emacs shell. package description width as
    # wide as the screen, and package name field small aptitude
    # manual can't figure out how wide emacs terminal is, of course
    # it doesn't consult the $COLUMNS variable...  and in a normal
    # terminal, it makes the package name field ridiculously big
    # also, remove that useless dash before the description
    aptitude -F "%c%a%M %p %$((COLUMNS - 30))d" -w $COLUMNS search "$@"
  }
  pu() {
    local s; [[ $EUID != 0 ]] && s=sudo
    local needed=false
    for arg; do
      if dpkg -s -- "$arg" &>/dev/null; then
        needed=true
        break
      fi
    done
    $needed || return 0
    plock-wait
    $s apt-get -y remove --purge --auto-remove  "$@"
    # seems slightly redundant, but it removes more stuff sometimes.
    $s apt-get -y autoremove
  }
  # shellcheck disable=SC2120
  pup() { # upgrade
    plock-wait
    pupdate
    local s; [[ $EUID != 0 ]] && s=sudo
    $s apt-get -y dist-upgrade --purge --auto-remove "$@"
    $s apt-get -y autoremove
  }
  # package info
  pl() {
    if type -p aptitude &>/dev/null; then
      aptitude show "$@"
    else
      apt-cache show "$@"
    fi
  }
  pfile() {
    # -a = search all repos
    local -a arg all
    all=false
    case $1 in
      -a)
        all=true
        shift
        ;;
    esac
    local file=$1
    # ucfq can tell us about config files which are not tracked
    # with apt-file. but, for at least a few files I tested
    # which are tracked with apt-file, ucfq doesn't show their
    # package name. So, commenting this, waiting to find
    # a config file only tracked by ucfq to see if it gives the
    # package name and if I can identify this kind of file.
    # if [[ $file == /* ]] && ! ucfq -w $file | grep ::: &>/dev/null; then
    #    ucfq $file

    if [[ $file == /* ]]; then
      dpkg -S "$file"
    else
      if ! $all; then
        arg=(--filter-origins "$(positive-origins)")
      fi
      if [[ $file == /* ]]; then
        apt-file "${arg[@]}" find -x /"$file"\$
        update-alternatives --list "$file" 2>/dev/null
      else
        apt-file "${arg[@]}" find -x "$file"\$
      fi
    fi
  }
  pkgfiles() {
    if dpkg -s "$1" &>/dev/null; then
      dpkg-query -L $1 | while read -r l; do [[ -f $l ]] && printf "%s\n" "$l"; done
    else
      apt-file -x list "^$1$"
    fi
  }

elif command -v pacman &>/dev/null; then
  p() {
    pacaur "$@"
  }
  pi() {
    pacaur -S --noconfirm --needed --noedit "$@"
  }
  pfd() {
    pacaur -Ss "$@"
  }
  pu() {
    pacaur -Rs --noconfirm "$@"
    if p=$(pacaur -Qdtq); then
      pacaur -Rs $p
    fi
  }
  aurex() {
    p="$1"
    aur='https://aur.archlinux.org'
    curl -s $aur/"$(curl -s "$aur/rpc.php?type=info&arg=$p" \
                     | jq -r .results.URLPath)" | tar xz
    cd "$p"

  }
  pmirror() {
    local s; [[ $EUID != 0 ]] && s=sudo
    local x
    x=$(mktemp)
    curl -s "https://www.archlinux.org/mirrorlist/\
?country=US&protocol=https&ip_version=4&ip_version=6&use_mirror_status=on" \
      | sed -r 's/^[ #]*(Server *=)/\1/' > $x
    if (( $(stat -c %s $x ) > 10 )); then
      $s cp $x /etc/pacman.d/mirrorlist
      rm $x
    fi
  }
  # shellcheck disable=SC2120
  pup() { # upgrade
    local s; [[ $EUID != 0 ]] && s=sudo
    # file_time + 24 hours > current_time
    if ! (( $(stat -c%Y /etc/pacman.d/mirrorlist) + 60*60*24 > $(date +%s) ))
    then
      pmirror
    fi
    pacaur -Syu --noconfirm "$@"
  }
  # package info
  pl() {
    pacaur -Si "$@"
  }
  pfile() {
    pkgfile "$1"
  }
  pkgfiles() {
    if pacaur -Qs "^$1$" &>/dev/null; then
      pacman -Ql $1
    else
      pkgfile -l $1
    fi
  }
fi