#compdef opkg ipkg

# Notes:
#
# - This function has been designed with opkg in mind, but much of it should
#   also work with ipkg.
#
# - Caching doesn't appear to save a HUGE amount of time given the scale of most
#   opkg repos (compared to e.g. APT) and the resources available to the devices
#   that use them.
#
# - _opkg_pkg_* functions can be called with --update to update their respective
#   cache files without actually completing.
#
# - Lots of code redundancy here (@todo).
#
# Notable styles supported:
#
# % zstyle ':completion:*:opkg:*' use-cache <yes/no>
#   Set to yes to enable caching of package names. Usually disabled by default.
#
# % zstyle ':completion:*:opkg:*' cache-path <directory>
#   Set to a directory path to override the default cache-file directory.
#
# % zstyle ':completion:*:opkg:*' cache-persists <yes/no>
#   Set to yes to keep cache data in memory for the remainder of the shell
#   session. Most completion functions do this always, but opkg tends to be used
#   on fairly resource-constrained devices, so it's disabled by default here.
#
# % zstyle ':completion:*:opkg:*' status-paths <pattern> ...
#   Set to one or more paths or glob patterns to override the defaults used when
#   checking cache validity. If any of the specified files has been modified
#   more recently than the cache, the cache is considered invalid.
#
# % zstyle ':completion:*:opkg:*' conf-paths <pattern> ...
#   Set to one or more paths or glob patterns to override the defaults used when
#   searching opkg configuration data.
#
# Elevated privileges may be necessary to complete package names, etc.; consider
# setting the gain-privileges style as follows:
# zstyle ':completion:*:(ipkg|opkg)/*' gain-privileges yes

##
# Check cache validity.
__opkg_cache_policy() {
  local -a tmp

  # Always invalidate if it's been over a week
  tmp=( $1(#qmw+1N) )
  (( $#tmp )) && return 0

  zstyle -a ":completion:$curcontext:" status-paths tmp

  if (( $#tmp )); then
    tmp=( $~tmp(#qN) )
  else
    tmp=(
      {/opt,/usr,/var}/lib/{i,o}pkg/status(#q-.N)
      {/opt,/usr,/var}/lib/{i,o}pkg/lists/packages(#q-.N)
      /opt/var/opkg-lists/packages(#q-.N)
    )
  fi

  # Always invalidate if we found no status files
  (( $#tmp )) || return 0

  # Invalidate if any status file is newer than the cache file
  for 2 in $tmp; do
    [[ $2 -nt $1 ]] && return 0
  done

  return 1
}

##
# Search opkg config files.
__opkg_grep_conf() {
  local -aU tmp

  zstyle -a ":completion:$curcontext:" conf-paths tmp

  if (( $#tmp )); then
    tmp=( $~tmp(#qN) )
  else
    tmp=(
      {,/opt}/etc/{i,o}pkg*.conf(#q-.N)
      {,/opt}/etc/{i,o}pkg/*.conf(#q-.N)
    )
  fi

  (( $#tmp )) || return 1

  GREP_OPTIONS= command grep -sE "$@" $tmp
}

##
# Complete architecture/priority pair.
#
# Architecture names are essentially arbitrary (up to the packager), so we can't
# really complete every possibility here — but we'll account for most of the
# popular ones.
_opkg_arch_prio() {
  local -a copts=( "$@" )
  local -aU tmp

  [[ -prefix *: ]] && {
    _message priority
    return
  }

  # Already configured arches
  tmp=( ${(f)"$( _call_program -p architectures $svc print-architecture )"} )
  tmp=( ${${tmp##arch[ ]##}%% *} )

  tmp+=(
    # 'Meta' arches
    all any noarch
    # Arches supported by entware-ng
    armv5soft armv7soft mipselsf x86-32 x86-64
    # Arches mentioned in the optware-ng source
    arm armeb fsg3be hpmv2 i686 ixp4xxbe ixp4xxle mssii nslu2 powerpc qemux86
    slugosbe slugosle
    # Arches mentioned in the Ångström distribution's narcissus source
    a780 ac100 akita am180x-evm am3517-crane am3517-evm am37x-evm archos5
    archos5it arm arm-oabi armeb armv4 armv4b armv4t armv4tb armv5 armv5-vfp
    armv5e armv5e-vfp armv5eb armv5t armv5t-vfp armv5te armv5te-vfp armv5teb
    armv6 armv6-vfp armv6t-vfp armv7 armv7-vfp armv7a armv7a-vfp armv7a-vfp-neon
    armv7at2-vfp armv7at2-vfp-neon armv7t2-vfp at32stk1000 at91sam9263ek
    atngw100 avr32 beagleboard beaglebone bug20 c6a816x-evm c6a816x_evm c7x0
    cm-t35 collie da830-omapl137-evm da850-omapl138-evm davinci-dvevm dht-walnut
    dm355-evm dm355-leopard dm357-evm dm365-evm dm3730-am3715-evm dm37x-evm
    dm6446-evm dm6467-evm dm6467t-evm dns323 eee701 efika h2200 h3900 h4000
    h5000 hawkboard htcalpine hx4700 i386 i486 i586 i686 igep0020 iwmmxt
    ixp4xxbe ixp4xxle kuropro lsppchd lsppchg lspro mini2440 mini6410 mips
    mv2120 n1200 n2100 neuros-osd2 nokia800 om-gta01 om-gta02 omap3-pandora
    omap3-touchbook omap3evm omap4430-panda omap4430_panda omap5912osk omapzoom
    omapzoom2 omapzoom36x openrd-base openrd-client overo palmt650 poodle
    powerpc ppc ppc405 ppc603e qemuarm qemumips qemuppc qemux86 sheevaplug
    simpad smartq5 spitz tosa ts409 tsx09 usrp-e1xx x86
  )

  _values -O copts -w -S : architecture ${^tmp}:priority
}

##
# Complete destination name.
_opkg_dest() {
  local -a copts=( "$@" )
  local -aU tmp

  tmp=( ${(f)"$( __opkg_grep_conf '^\s*dest\s+\S+\s+\S+' )"} )
  tmp=( ${tmp##[[:space:]]#dest[[:space:]]##} )
  tmp=( ${tmp%%[[:space:]]*} )

  (( $#tmp )) || {
    _message destination
    return
  }
  _values -O copts -w destination $tmp
}

##
# Complete destination-name/path pair.
_opkg_dest_path() {
  local -a copts=( "$@" )
  local -aU tmp

  tmp=( ${(f)"$( __opkg_grep_conf '^\s*dest\s+\S+\s+\S+' )"} )
  tmp=( ${tmp##[[:space:]]#dest[[:space:]]##} )
  tmp=( ${tmp%%[[:space:]]*} )

  (( $#tmp )) || {
    _message destination:path
    return
  }
  _values -O copts -w -S : destination ${^tmp}': :_directories'
}

##
# Complete any package name.
_opkg_pkg_all() {
  local -a upd copts

  zparseopts -a upd -D -E - -update
  copts=( "$@" )

  { (( ! $#_opkg_cache_pkg_all )) || _cache_invalid opkg-pkg-all } &&
  ! _retrieve_cache opkg-pkg-all && {
    _opkg_cache_pkg_all=( ${(f)"$(
      _call_program -p pkg-all ${svc:-opkg} list )"}
    )
    _opkg_cache_pkg_all=( ${(@)_opkg_cache_pkg_all##[[:space:]]*} )
    _opkg_cache_pkg_all=( ${(@)_opkg_cache_pkg_all%%[[:space:]]*} )
    _store_cache opkg-pkg-all _opkg_cache_pkg_all
  }
  (( $#upd )) && return 0

  (( $#_opkg_cache_pkg_all )) || {
    _message package
    return
  }
  _values -O copts -w package $_opkg_cache_pkg_all
}

##
# Complete installed package name.
_opkg_pkg_inst() {
  local -a upd copts

  zparseopts -a upd -D -E - -update
  copts=( "$@" )

  { (( ! $#_opkg_cache_pkg_inst )) || _cache_invalid opkg-pkg-inst } &&
  ! _retrieve_cache opkg-pkg-inst && {
    _opkg_cache_pkg_inst=( ${(f)"$(
      _call_program -p pkg-inst ${svc:-opkg} list-installed
    )"} )
    _opkg_cache_pkg_inst=( ${(@)_opkg_cache_pkg_inst##[[:space:]]*} )
    _opkg_cache_pkg_inst=( ${(@)_opkg_cache_pkg_inst%%[[:space:]]*} )
    _store_cache opkg-pkg-inst _opkg_cache_pkg_inst
  }
  (( $#upd )) && return 0

  (( $#_opkg_cache_pkg_inst )) || {
    _message 'installed package'
    return
  }
  _values -O copts -w 'installed package' $_opkg_cache_pkg_inst
}

##
# Complete new (installable) package name.
_opkg_pkg_new() {
  local -a upd copts

  zparseopts -a upd -D -E - -update
  copts=( "$@" )

  { (( ! $#_opkg_cache_pkg_new )) || _cache_invalid opkg-pkg-new } &&
  ! _retrieve_cache opkg-pkg-new && {
    _opkg_pkg_all  --update
    _opkg_pkg_inst --update
    _opkg_cache_pkg_new=( ${_opkg_cache_pkg_all:|_opkg_cache_pkg_inst} )
    _store_cache opkg-pkg-new _opkg_cache_pkg_new
  }
  (( $#upd )) && return 0

  (( $#_opkg_cache_pkg_new )) || {
    _message 'installable package'
    return
  }
  _values -O copts -w 'installable package' $_opkg_cache_pkg_new
}

##
# Complete upgradeable package name.
_opkg_pkg_upgr() {
  local -a upd copts

  zparseopts -a upd -D -E - -update
  copts=( "$@" )

  { (( ! $#_opkg_cache_pkg_upgr )) || _cache_invalid opkg-pkg-upgr } &&
  ! _retrieve_cache opkg-pkg-upgr && {
    _opkg_cache_pkg_upgr=( ${(f)"$(
      _call_program -p pkg-upgr ${svc:-opkg} list-upgradable
    )"} )
    _opkg_cache_pkg_upgr=( ${(@)_opkg_cache_pkg_upgr##[[:space:]]*} )
    _opkg_cache_pkg_upgr=( ${(@)_opkg_cache_pkg_upgr%%[[:space:]]*} )
    _store_cache opkg-pkg-upgr _opkg_cache_pkg_upgr
  }
  (( $#upd )) && return 0

  (( $#_opkg_cache_pkg_upgr )) || {
    _message 'upgradable package'
    return
  }
  _values -O copts -w 'upgradable package' $_opkg_cache_pkg_upgr
}

_opkg() {
  local curcontext=$curcontext ret=1 cache_policy help variant svc=$words[1]
  local -a line state state_descr args tmp
  local -A opt_args val_args

  if
    zstyle -t ":completion:*:*:$service:*" cache-persists &&
    (( ! $+_opkg_cache_pkg_all ))
  then
    typeset -gaU _opkg_cache_pkg_all
    typeset -gaU _opkg_cache_pkg_inst
    typeset -gaU _opkg_cache_pkg_new
    typeset -gaU _opkg_cache_pkg_upgr
  else
    local -aU _opkg_cache_pkg_all
    local -aU _opkg_cache_pkg_inst
    local -aU _opkg_cache_pkg_new
    local -aU _opkg_cache_pkg_upgr
  fi

  zstyle -s ":completion:*:*:$service:*" cache-policy cache_policy
  [[ -n $cache_policy ]] ||
  zstyle ":completion:*:*:$service:*" cache-policy __opkg_cache_policy

  # Options are ordered by long name. Alternative names not listed in the usage
  # help are (mostly) ignored
  args=(
    '*--add-arch=[register architecture with priority]: :_opkg_arch_prio'
    '*--add-dest=[register destination with path]: :_opkg_dest_path'
    '--autoremove[remove unnecessary packages]'
    '--combine[combine upgrade and install operations]'
    '(-f --conf)'{-f+,--conf=}'[specify opkg config file]:config file:_files'
    '(-d --dest)'{-d+,--dest=}'[specify root directory for package operations]: :_opkg_dest'
    '--download-only[make no changes (download only)]'
    '--force-checksum[ignore checksum mismatches]'
    '--force-downgrade[allow package downgrades]'
    '--force-depends[ignore failed dependencies]'
    '(--force-maintainer --ignore-maintainer)--force-maintainer[overwrite local config files with upstream changes]'
    '--force-overwrite[overwrite files from other packages]'
    '--force-postinstall[always run postinstall scripts]'
    '--force-reinstall[reinstall packages]'
    # This is obnoxiously long; maybe add --force-removal-* to ignored-patterns
    '--force-removal-of-dependent-packages[remove packages and all dependencies]'
    '--force-remove[ignore failed prerm scripts]'
    '--force-space[disable free-space checks]'
    '(--force-maintainer --ignore-maintainer)--ignore-maintainer[ignore upstream changes to config files]'
    '(-l --lists-dir)'{-l+,--lists-dir=}'[specify package-list directory]:list directory:_directories'
    '(--noaction --test)'{--noaction,--test}'[make no changes (test only)]'
    '--nodeps[do not follow dependencies]'
    # Undocumented variant
    '!(-o --offline --offline-root)--offline=:root directory:_directories'
    '(-o --offline --offline-root)'{-o+,--offline-root=}'[specify root directory for offline package operations]:root directory:_directories'
    '(-A --query-all)'{-A,--query-all}'[query all packages (not just installed)]'
    '--recursive[remove packages and all their dependencies]'
    '--size[show package sizes]'
    '(-t --tmp-dir)'{-t+,--tmp-dir=}'[specify temp directory]:temp directory:_directories'
    '(-V --verbosity)'{-V+,--verbosity=}'[specify output verbosity level]: :->verbosity-levels'
    '(: -)'{-v,--version}'[display version information]'
    '1: :->commands'
    '*::: :->extra'
  )

  # There are a few different variants of opkg, but we'll concern ourselves
  # mainly with OpenWRT/Entware vs (up-stream) Yocto
  _pick_variant -r variant openwrt=--nocase yocto --help

  if [[ $variant == openwrt ]]; then
    args+=(
      '--cache=[specify cache directory]:cache directory:_directories'
      '--nocase[match patterns case-insensitively]'
    )
  else
    args+=(
      '*--add-exclude=[register package for exclusion]: :_opkg_pkg_all'
      '--cache-dir=[specify cache directory]:cache directory:_directories'
      '--host-cache-dir[do not place cache in offline root directory]'
      '--no-install-recommends[do not install recommended packages]'
      '--prefer-arch-to-version[prefer higher architecture priorities to higher versions]'
      '--volatile-cache[use volatile download cache]'
    )
  fi

  _arguments -s -S -C : $args && ret=0

  case $state in
    commands)
      tmp=(
        'compare-versions[compare version numbers]'
        'configure[configure unpacked package]'
        'depends[display dependencies of package]'
        'download[download package]'
        'files[display files belonging to package]'
        'find[search package names and descriptions]'
        'flag[flag package]'
        'info[display package information]'
        'install[install package]'
        'list[display available packages]'
        'list-changed-conffiles[display user-modified config files]'
        'list-installed[display installed packages]'
        'list-upgradable[display upgradable packages]'
        'print-architecture[display installable architectures]'
        'remove[remove package]'
        'search[display packages providing file]'
        'status[display package status]'
        'update[update list of available packages]'
        'upgrade[upgrade installed package]'
        'whatconflicts[display what conflicts with package]'
        'whatdepends[display what depends on package]'
        'whatdependsrec[display what depends on package (recursive)]'
        'whatprovides[display what provides package]'
        'whatrecommends[display what recommends package]'
        'whatreplaces[display what replaces package]'
        'whatsuggests[display what suggests package]'
      )
      [[ $variant == openwrt ]] ||
      tmp+=( 'clean[clean internal cache]' )

      _values sub-command $tmp && ret=0
      ;;
    verbosity-levels)
      _values 'verbosity level' \
        '0[show errors only]' \
        '1[show normal messages (default)]' \
        '2[show informational message]' \
        '3[show debug messages (level 1)]' \
        '4[show debug messages (level 2)]' \
      && ret=0
      ;;
    extra)
      case $line[1] in
        compare-versions)
          case $CURRENT in
            1|3) _message 'version string' && ret=0 ;;
            2)
              _values operator \
                '<<[earlier]' \
                '<=[earlier or equal]' \
                '=[equal]' \
                '>=[later or equal]' \
                '>>[later]' \
              && ret=0
              ;;
          esac
          ;;
        configure|files|list-*|status)
          (( CURRENT == 1 )) && _opkg_pkg_inst && ret=0
          ;;
        depends|what*)
          if [[ -n ${opt_args[(I)-A|--query-all]} ]]; then
            _opkg_pkg_all && ret=0
          else
            _opkg_pkg_inst && ret=0
          fi
          ;;
        download)
          _opkg_pkg_all && ret=0
          ;;
        find|info|list)
          (( CURRENT == 1 )) && _opkg_pkg_all && ret=0
          ;;
        flag)
          if (( CURRENT == 1 )); then
            _values flag hold noprune user ok installed unpacked && ret=0
          else
            _opkg_pkg_inst && ret=0
          fi
          ;;
        install)
          _opkg_pkg_new && ret=0
          ;;
        remove)
          _opkg_pkg_inst && ret=0
          ;;
        search)
          (( CURRENT == 1 )) && _files && ret=0
          ;;
        upgrade)
          _opkg_pkg_upgr && ret=0
          ;;
      esac
      ;;
  esac

  (( ret && $#state )) && _message 'no more arguments' && ret=0
  return ret
}

_opkg "$@"
