setup

#!/usr/bin/env sh

# init
# Author: Lucas Larson
#
# Description: bootstrap a new machine
# Assumptions: installation target is one of Arch Linux or Alpine Linux

# Alpine Linux
# wget -O- https://lucaslarson.net/setup | sh

# Arch Linux
# curl https://lucaslarson.net/setup | sh

if command -v -- apk >/dev/null 2>&1; then
  alias install='command apk add --verbose'
elif command -v -- pacman >/dev/null 2>&1; then
  alias install='command pacman --sync --verbose --noconfirm'
elif command -v -- apt-get >/dev/null 2>&1; then
  alias install='command apt-get install --show-progress --assume-yes'
fi

command -p -- printf -- '\n\n   .\137\137       .\137\137  \137\137\n' >&2
command -p -- printf -- '   \174\137\137\174 \137\137\137\137 \174\137\137\174\057  \174\137\n' >&2
command -p -- printf -- '   \174  \174\057    \134\174  \134   \137\137\134\n' >&2
command -p -- printf -- '   \174  \174   \174  \134  \174\174  \174\n' >&2
command -p -- printf -- '   \174\137\137\174\137\137\137\174' >&2
command -p -- printf -- '  \057\137\137\174\174\137\137\174\n' >&2
command -p -- printf -- '           \134\057\n\n' >&2
command -p -- printf -- '        Linux setup\n' >&2
command -p -- sleep 1
command -p -- printf -- '  a Lucas Larson production\n\n' >&2
command -p -- sleep 1

# save `date` for backup files
now="$(command -p -- date -- '+%Y%m%d%H%M%S')"

# unset `$PS4`
# if this quaternary prompt string is already unset, then
# set it to the POSIX default: `+ `
# https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
ps4_temporary="${PS4:-+ }"
unset -v -- PS4 2>/dev/null || PS4=''
set -o xtrace

# pacman
# https://askubuntu.com/a/459425
command -v -- pacman >/dev/null 2>&1 && {
  install --refresh --refresh ||
    # https://wiki.archlinux.org/?oldid=667441#Installing_packages
    install --refresh --sysupgrade 2>/dev/null
}

# apk
command -v -- apk >/dev/null 2>&1 || {
  # trust apk only if it matches a known checksum
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'verifying apk tools integrity...\n' >&2
  set -o xtrace
  # https://web.archive.org/web/20201127045648id_/github.com/ish-app/ish/wiki/Installing-apk-on-the-App-Store-Version#wiki-body
  command wget --output-document=- -- 'https://dl-cdn.alpinelinux.org/alpine/v3.16/main/'"$(command -p -- uname -m)"'/apk-tools-static-2.12.9-r3.apk' |
    command tar --extract --gzip --strip-components=1 --verbose -- sbin/apk.static &&
    ./apk.static add apk-tools &&
    command -p -- rm -- ./apk.static

  # configure only main and community repositories at first
  command -p -- mkdir -p -- '/etc/apk' && {
    command -p -- printf -- 'https://dl-cdn.alpinelinux.org/alpine/latest-stable/main\n'
    command -p -- printf -- 'https://dl-cdn.alpinelinux.org/alpine/latest-stable/community\n'
  } >'/etc/apk/repositories'

  # update
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'updating Alpine Linux repositories...\n' >&2
  set -o xtrace
  command apk update --verbose --progress
  command apk upgrade --verbose --progress
}

# https://wiki.alpinelinux.org/w/index.php?oldid=17773&title=How_to_get_regular_stuff_working#Man_pages
# man-pages adds `man0`, `man2`, man4`, `man6` to `/usr/share/man/`
{ command -p -- test -d '/usr/share/man/man0' &&
  command -p -- test -d '/usr/share/man/man2' &&
  command -p -- test -d '/usr/share/man/man4' &&
  command -p -- test -d '/usr/share/man/man6'; } || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing man pages...\n' >&2
  set -o xtrace
  install man-pages
}
command -v -- mandoc >/dev/null 2>&1 || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing mandoc for man pages...\n' >&2
  set -o xtrace
  install mandoc
}
command -v -- less >/dev/null 2>&1 || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing less to read man pages...\n' >&2
  set -o xtrace
  install less
}

# https://wiki.alpinelinux.org/w/index.php?oldid=17773&title=How_to_get_regular_stuff_working#Shell_.40_commandline
# https://web.archive.org/web/20210218201739id_/web.archive.org/screenshot/docs.google.com/document/d/10-8wjANQGbG43XZ0wN57M1RYOLUwu9RZATNe9vJQYKw/mobilebasic
# https://wiki.alpinelinux.org/w/index.php?oldid=18038&title=Alpine_newbie_apk_packages#coreutils_libc_and_utmps_in_alpine
install coreutils
{ command -p -- test -x '/usr/bin/coreutils' &&
  command -p -- find --version >/dev/null 2>&1 | command -p -- grep -e 'findutils' >/dev/null 2>&1; } || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing Linux utilities...\n' >&2
  set -o xtrace
}
install util-linux pciutils usbutils coreutils binutils findutils grep wget curl openssl sudo sed attr dialog readline

# add additional Alpine Linux repositories if applicable
command -v -- apk >/dev/null 2>&1 &&
  command -p -- test -s '/etc/apk/repositories' && {
  {
    command -p -- printf -- 'https://dl-cdn.alpinelinux.org/alpine/edge/main\n'
    command -p -- printf -- 'https://dl-cdn.alpinelinux.org/alpine/edge/community\n'
    command -p -- printf -- 'https://dl-cdn.alpinelinux.org/alpine/edge/testing\n'
  } >>'/etc/apk/repositories' &&
    command apk update
}

# ssh
# https://wiki.alpinelinux.org/w/index.php?oldid=13842&title=Setting_up_a_ssh-server#OpenSSH
command -p -- test -d '/etc/ssh' || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing OpenSSH...\n' >&2
  set -o xtrace
  install openssh
}

# gpg
# https://wiki.alpinelinux.org/w/index.php?oldid=17295&title=Setting_up_a_laptop#Creating_GPG_keys
command -p -- test -x '/usr/bin/gpg2' || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing GPG...\n' >&2
  set -o xtrace
  install gnupg
}

# git
command -v -- git >/dev/null 2>&1 || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing Git...\n' >&2
  set -o xtrace
  install git
}

# git user
command git config --global --get user.name >/dev/null 2>&1 || {
  command git config --global user.name 'Lucas Larson'
}

# git default branch
command git config --global --get init.defaultBranch >/dev/null 2>&1 || {
  command git config --global init.defaultBranch 'main'
}

# time zone
{ set +o xtrace; } 2>/dev/null
command -p -- printf -- 'updating time zone information...\n' >&2
set -o xtrace
install --no-cache tzdata

# python
{ set +o xtrace; } 2>/dev/null
command -p -- printf -- 'checking Python installation...\n' >&2
set -o xtrace
command -v -- python >/dev/null 2>&1 || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing Python...\n' >&2
  set -o xtrace
  install python3
}

# zsh
command -v -- zsh >/dev/null 2>&1 || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing Zsh...\n' >&2
  set -o xtrace
  install zsh
}

# chsh
# part of shadow on Alpine Linux
command -v -- chsh >/dev/null 2>&1 || {
  install shadow
}

# Oh My Zsh
command -v -- omz >/dev/null 2>&1 ||
  command -p -- test -d "${ZSH:=${HOME%/}/.oh-my-zsh}" || {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'installing Oh My Zsh...\n' >&2
  if command -v -- wget >/dev/null 2>&1; then
    set -o xtrace
    command -p -- sh -c "$(command wget 'https://github.com/ohmyzsh/ohmyzsh/raw/HEAD/tools/install.sh' --output-document=-)" --unattended --keep-zshrc
  elif command -v -- curl >/dev/null 2>&1; then
    set -o xtrace
    command -p -- sh -c "$(command curl --location --url 'https://github.com/ohmyzsh/ohmyzsh/raw/HEAD/tools/install.sh')" --unattended --keep-zshrc
  fi
  { set +o xtrace; } 2>/dev/null
}

# update, repair everything again before close
command -v -- apk >/dev/null 2>&1 && {
  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'updating...\n' >&2
  set -o xtrace
  command apk update --verbose --verbose --progress

  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'upgrading...\n' >&2
  set -o xtrace
  command apk upgrade --verbose --verbose --progress

  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'repairing and resolving dependencies...\n' >&2
  set -o xtrace
  command apk fix --verbose --verbose --depends --progress

  { set +o xtrace; } 2>/dev/null
  command -p -- printf -- 'verifying installations...\n' >&2
  set -o xtrace
  command apk verify --verbose --verbose --progress
}

# cleanup
{ set +o xtrace; } 2>/dev/null
command -p -- printf -- 'cleaning up temporary installation files and performing housekeeping...\n' >&2
set -o xtrace

# message of the day
command -p -- test -w '/etc/motd' &&
  command -p -- cp -- '/etc/motd' '/etc/motd-'"${now-}" &&
  command -p -- printf -- '' >'/etc/motd'

# delete thumbnail cache files
command -p -- find -- . \
  -type f \
  '(' \
  -name '.DS_Store' -o \
  -name 'Desktop.ini' -o \
  -name 'Thumbs.db' -o \
  -name 'desktop.ini' -o \
  -name 'thumbs.db' \
  ')' \
  -delete 2>/dev/null

# delete empty files
# except those within `.git/` directories
# and those with specific names
command -p -- find -- . \
  -type f \
  -size 0 \
  -path '*/.git' -prune -o \
  -path '*example*' -prune -o \
  -path '*sample*' -prune -o \
  -path '*template*' -prune -o \
  -path '*test*' -prune -o \
  ! -name "$(command -p -- printf -- 'Icon\015\012')" \
  ! -name '*LOCK' \
  ! -name '*empty*' \
  ! -name '*hushlogin' \
  ! -name '*ignore' \
  ! -name '*journal' \
  ! -name '*lock' \
  ! -name '*lockfile' \
  ! -name '.dirstamp' \
  ! -name '.gitkeep' \
  ! -name '.gitmodules' \
  ! -name '.keep' \
  ! -name '.sudo_as_admin_successful' \
  ! -name '.watchmanconfig' \
  ! -name '__init__.py' \
  ! -name 'favicon.*' \
  -delete 2>/dev/null

# delete empty directories recursively
# but skip Git-specific and `/.well-known/` directories
command -p -- find -- . -type d -links 2 \
  -path '*/.git' -prune -o \
  -path '*/.well-known' -prune -o \
  -delete 2>/dev/null

# if the shell can be changed and
# if zsh is available, then replace bash, ash, and sh with zsh in `/etc/passwd`
command -p -- test -w '/etc/passwd' &&
  command -v -- zsh >/dev/null 2>&1 &&
  command -p -- grep -E -e '/bin/b?a?sh' '/etc/passwd' >/dev/null 2>&1 &&
  command -p -- cp -- '/etc/passwd' '/etc/passwd-'"${now-}" &&
  command -p -- sed -e 's|/bin/b\{0,1\}a\{0,1\}sh$|'"$(command -v -- zsh)"'|' '/etc/passwd-'"${now-}" >'/etc/passwd'

# done
{ set +o xtrace; } 2>/dev/null
command -p -- printf -- 'installation complete\n' >&2
command -p -- sleep 1
command -p -- printf -- 'exiting to apply updates...\n' >&2

# restore `$PS4`
PS4="${ps4_temporary:-+ }"
unset -v -- ps4_temporary 2>/dev/null || ps4_temporary=''

{
  command -p -- printf -- '\n'
  command -p -- printf -- 'done!\n'
} >&2

exit