#!/bin/bash

# update an archlinux32 package
#   devtools
#   linux-pae (no upstream)
#   linux
#   linux-lts
#   linux-zen

git_repo_path='/usr/src/archlinux32/packages'
upstream_git_path='/usr/src/archlinux/packages'
archlinuxewe_git_path=~erich/'eigeneSkripte/archPackages'
vagrant_path=$(
  readlink -f ~/"virtual-boxes/archlinux32-test"
)
base_dir=$(
  dirname "$(
    readlink -f "$0"
  )"
)

if [ "x$1" = "x-" ]; then
  shift
else
  if ! git -C "${git_repo_path}" pull --ff-only || \
    ! git -C "${upstream_git_path}" pull --ff-only || \
    ! git -C "${archlinuxewe_git_path}" pull --ff-only; then
    >&2 echo 'Your git repos cannot cleanly be updated'
    exit 1
  fi
fi

case $# in
  0)
    >&2 echo "usage: $0 pkg1 pkg2 ..."
    exit 1
  ;;
  1)
  ;;
  *)
    for param in "$@"; do
      "$0" - "${param}" || exit $?
    done
    exit 0
  ;;
esac

pkgname="$1"
repo=$(
  git -C "${git_repo_path}" archive HEAD -- | \
    tar -t --wildcards "*/${pkgname}/PKGBUILD" | \
    cut -d/ -f1
)

if [ "$(printf '%s\n' "${repo}" | wc -l)" -ne 1 ]; then
  >&2 printf 'package "%s" does not exist in exactly one repository\n' "${pkgname}"
  exit 1
fi

update_checksum() {
  checksums=$(
    ssh arch32-test '
      cd '"${pkgname}"'
      makepkg -g
    ' | \
      sed '
        $! s/$/\\n/
      ' | \
      tr -d '\n'
  )
  sed -i '
    /^\S\+sums=(/{
      :a
      N
      /)/!ba
      s/^\S\+sums=(.*)/'"${checksums}"'/
    }
  ' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
}

# selecting the "update path"
case "${pkgname}" in
  'devtools')
    # a package which is in [archlinuxewe] -> mostly upstream, but with
    # replaced sources, checksums and pkgver (might be identical to
    # upstream, though)
    update_path='archlinuxewe'
  ;;
  'flashplugin')
    # an upstream package which is updated by solely updating its checksum
    update_path='checksum'
  ;;
  'linux'|'linux-lts'|'linux-zen')
    # a kernel which exists upstream -> different config and checksums
    update_path='kernel with upstream'
  ;;
  'linux-pae')
    # a kernel which does not exist upstream -> complete package sources
    # in our repository
    update_path='kernel without upstream'
  ;;
  *)
    >&2 printf 'I don'"'"'t know how to update package "%s"\n' "${pkgname}"
    exit 1
  ;;
esac

if ssh -o ConnectTimeout=1 arch32-test true; then
  vm_is_running=true
else
  vm_is_running=false
fi

if ! ${vm_is_running}; then
  cd "${vagrant_path}"
  vagrant up
fi

ssh arch32-test 'rm -rf --one-file-system "'"${pkgname}"'"'

case ${update_path} in
  'archlinuxewe')
    archlinuxewe_PKGBUILD=$(
      git -C "${archlinuxewe_git_path}" archive HEAD -- "${pkgname}32/PKGBUILD" | \
        tar -Ox
    )
    repo_arch=$(
      printf '%s\n' "${archlinuxewe_PKGBUILD}" | \
        grep '^arch=' | \
        cut -d'=' -f2 | \
        tr '()"'"'" '\n' | \
        grep -xF 'x86_64' || \
        echo any
    )
    old_pkgver=$(
      grep '^pkgver=' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD" | \
        cut -d'=' -f2
    )
    if [ "${old_pkgver}" = "${new_pkgver}" ]; then
      >&2 echo 'nothing to do'
      exit
    fi
    new_pkgver=$(
      printf '%s\n' "${archlinuxewe_PKGBUILD}" | \
        grep '^pkgver=' | \
        cut -d'=' -f2
    )
    sha512sums=$(
      cd "${archlinuxewe_git_path}/${pkgname}32"
      makepkg -g | \
        sed '
          s/^/\\1/
          $! s/$/\\n/
        ' | \
        tr -d '\n'
    )
    sed -i '
      s/^pkgver=.*/pkgver='"${new_pkgver}"'/
      s/^pkgrel=.*/pkgrel=1/
      /^\s*sha512sums=(/ {
        :sum_loop
        $b
        N
        s/^\(\s*\)sha512sums=(.*)/'"${sha512sums}"'/
        T sum_loop
      }
    ' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    scp -r "${upstream_git_path}/${pkgname}/repos/${repo}-${repo_arch}" \
      "arch32-test:${pkgname}"
    if ! ssh arch32-test '
        cd "'"${pkgname}"'"
        cat >> PKGBUILD
        makepkg --verifysource
      ' < \
        "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"; then
      >&2 echo 'something went wrong'
      exit 1
    fi
    git -C "${git_repo_path}" commit "${repo}/${pkgname}/PKGBUILD" -m "${repo}/${pkgname}: ${old_pkgver} -> ${new_pkgver}"
  ;;
  'checksum')
    repo_arch=$(
      git -C "${upstream_git_path}/${pkgname}/repos" archive HEAD -- | \
        tar -t | \
        sed 's/^'"${repo}-"'//;t;d' | \
        head -n1
    )
    scp -r "${upstream_git_path}/${pkgname}/repos/${repo}-${repo_arch}" \
      "arch32-test:${pkgname}"
    sums=$(
      ssh arch32-test '
        cd "'"${pkgname}"'"
        cat >> PKGBUILD
        echo "arch+=(i686)" >> PKGBUILD
        makepkg -g
      ' < "${git_repo_path}/${repo}/${pkgname}/PKGBUILD" \
        | sed '
          $! s/$/\\n/
        ' | \
        tr -d '\n'
    )
    echo "'$sums'"
    sed -i '
      /^\S\+sums=(/{
        :a
          $b
          N
          s/^\S\+sums=(.*)/'"${sums}"'/
      }
    ' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    if ! cat "${upstream_git_path}/${pkgname}/repos/${repo}-${repo_arch}/PKGBUILD" "${git_repo_path}/${repo}/${pkgname}/PKGBUILD" \
      | ssh arch32-test '
        cd "'"${pkgname}"'"
        cat > PKGBUILD
        echo "arch+=(i686)" >> PKGBUILD
        makepkg --verifysource
      '; then
      >&2 echo 'something went wrong'
      exit 1
    fi
    git -C "${git_repo_path}" commit "${repo}/${pkgname}/PKGBUILD" -m "${repo}/${pkgname}: new version => new checksum"
  ;;
  'kernel without upstream')
    infos=$(
      "${base_dir}/watch-versions" "${pkgname}"
    )
    if [ -z "${infos}" ]; then
      >&2 echo 'Nothing to do.'
      exit
    fi
    old_pkgver=$(
      printf '%s\n' "${infos}" | \
        cut -d' ' -f4
    )
    new_pkgver=$(
      printf '%s\n' "${infos}" | \
        cut -d' ' -f2
    )
    sed -i '
      s/^pkgver=.*$/pkgver='"'${new_pkgver}'"'/
      s/^pkgrel=.*$/pkgrel='"'1'"'/
    ' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    scp -r "${git_repo_path}/${repo}/${pkgname}" 'arch32-test:'
    update_checksum

    case "${pkgname}" in
      'linux-pae')
        scp "${git_repo_path}/${repo}/${pkgname}/PKGBUILD" 'arch32-test:'"${pkgname}/"
        ssh arch32-test '
          cd '"${pkgname}"'
          sed -i '"'"'
            /make oldconfig/ s/^\s*#//
            s/^}$/return 1\n\0/
          '"'"' PKGBUILD
          makepkg -fcrs --asdeps --noconfirm
          cp src/linux-'"${new_pkgver}"'/.config config
        '
        update_checksum
        scp 'arch32-test:'"${pkgname}"'/config' "${git_repo_path}/${repo}/${pkgname}/"
        git -C "${git_repo_path}/${repo}/${pkgname}" add 'PKGBUILD' 'config'
      ;;
      *)
        >&2 printf 'Whoops, I thought %s should be updated as %s, but I don'"'"'t know the details.\n' \
          "${pkgname}" "${update_path}"
        exit 1
      ;;
    esac

    git -C "${git_repo_path}" commit -m "${repo}/${pkgname}: ${old_pkgver} -> ${new_pkgver}"
  ;;
  'kernel with upstream')
    old_revision=$(
      sed -n '
        s/^# upstream git\( revision\)\?: *//
        T
        p
      ' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    )
    if [ -z "${old_revision}" ]; then
      >&2 printf 'Cannot determine old upstream git revision of "%s".\n' "${pkgname}"
      >&2 echo '"# upstream git revision: ..." line is missing.'
      exit 1
    fi
    config_names=$(
      git -C "${git_repo_path}/${repo}/${pkgname}" archive HEAD -- | \
        tar -t | \
        grep '^config\($\|\.\)' | \
        tr '\n' ' '
    )
    diff=$(
      diff -u <(
          git -C "${upstream_git_path}/${pkgname}/repos/${repo}-x86_64" archive "${old_revision}" -- config | \
            tar -Ox | \
            sort
        ) \
        <(
          git -C "${upstream_git_path}/${pkgname}/repos/${repo}-x86_64" archive HEAD -- config | \
            tar -Ox | \
            sort
        ) | \
        grep '^[+-].' | \
        grep -v '^+++\|^---'
    )
    if [ -z "${diff}" ]; then
      >&2 echo 'nothing changed.'
      exit 0
    fi
    for config_name in ${config_names}; do
      {
        grep -vxF "$(
          printf '%s\n' "${diff}" | \
            sed '
              s/^-//
              t
              d
            '
        )" "${git_repo_path}/${repo}/${pkgname}/${config_name}"
        printf '%s\n' "${diff}" | \
          sed '
            s/^+//
            t
            d
          '
      } | \
        sponge "${git_repo_path}/${repo}/${pkgname}/${config_name}"
    done
    sed -i '
      1 s/^#.*$/# upstream git revision: '"$(
        git -C "${upstream_git_path}" rev-parse HEAD
      )"'/
      s/'"$(
        git -C "${upstream_git_path}/${pkgname}/repos/${repo}-x86_64" archive "${old_revision}" -- config | \
          tar -Ox | \
          sha256sum | \
          awk '{print $1}'
      )"'/'"$(
        git -C "${upstream_git_path}/${pkgname}/repos/${repo}-x86_64" archive HEAD -- config | \
          tar -Ox | \
          sha256sum | \
          awk '{print $1}'
      )"'/g
      ' "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    {
      git -C "${upstream_git_path}/${pkgname}/repos/${repo}-x86_64" archive HEAD --
      for config_name in ${config_names}; do
        tar -c -C "${git_repo_path}/${repo}/${pkgname}" "${config_name}"
      done
    } | \
      ssh arch32-test '
        mkdir "'"${pkgname}"'"
        tar -xiC "'"${pkgname}"'"
      '
    ssh arch32-test '
      cd "'"${pkgname}"'"
      cat >> PKGBUILD
      sed -i '"'"'
        '"$(
          for config_name in ${config_names}; do
            printf 's/'
            git -C "${git_repo_path}/${repo}/${pkgname}" archive HEAD -- "${config_name}" | \
              tar -Ox | \
              sha256sum | \
              awk '{print $1}' | \
              tr -d '\n'
            printf '/SKIP/g\n'
          done
        )"'
        /^arch=[^#]*any/!{
          /^arch=(/s/(/(i486 i686 pentium3 /
        }
        /make oldconfig/ s/^\s*#//
        s/^}$/return 1\n\0/
      '"'"' PKGBUILD
    ' < \
      "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    ssh arch32-test '
      cd "'"${pkgname}"'"
      eval "$(grep '"'"'^_srcname='"'"' PKGBUILD)"
      for config_name in '"${config_names}"'; do
        rm -rf --one-file-system src pkg
        if [ "${config_name}" = "config" ]; then
          makepkg -fcrs --asdeps --noconfirm
        else
          CARCH=${config_name#config.} makepkg -fcrs --asdeps --noconfirm
        fi
        mv src/${_srcname}/.config ${config_name}
      done
    '
    for config_name in ${config_names}; do
      scp "arch32-test:${pkgname}/${config_name}" "${git_repo_path}/${repo}/${pkgname}/"
    done
    sed -i "$(
      for config_name in ${config_names}; do
        printf 's/'
        git -C "${git_repo_path}/${repo}/${pkgname}" archive HEAD -- "${config_name}" | \
          tar -Ox | \
          sha256sum | \
          awk '{print $1}' | \
          tr -d '\n'
        printf '/'
        sha256sum "${git_repo_path}/${repo}/${pkgname}/${config_name}" | \
          awk '{print $1}' | \
          tr -d '\n'
        printf '/g\n'
      done
    )" "${git_repo_path}/${repo}/${pkgname}/PKGBUILD"
    git -C "${git_repo_path}/${repo}/${pkgname}" commit PKGBUILD ${config_names} -m "${repo}/${pkgname}: new version => new config => new checksum"
  ;;
  *)
    >&2 printf 'Whoops, I thought I knew how to update %s, but apparently I don'"'"'t.\n' \
      "${update_path}"
    exit 1
  ;;
esac

ssh arch32-test 'rm -rf --one-file-system '"${pkgname}"

if ! ${vm_is_running}; then
  ssh arch32-test 'sudo poweroff'
  err=$?
  if [ ${err} -eq 255 ]; then
    err=0
  fi
  exit ${err}
fi