#!/bin/bash

set -e

mirror_dir='/mnt/archlinux32'
website_dir='/usr/src/github/archlinux32/website'

usage() {
  >&2 echo ''
  >&2 echo 'get-package-updates: check for packages that need to be built,'
  >&2 echo ' and build a list in the proper build order'
  >&2 echo ''
  >&2 echo 'possible options:'
  >&2 echo '  -h|--help:    Show this help and exit.'
  >&2 echo '  --magnet-i686 $link:'
  >&2 echo '                Set archiso-i686 magnet link to $link.'
  >&2 echo '  --magnet-dual $link:'
  >&2 echo '                Set archiso-dual magnet link to $link.'
  [ -z "$1" ] && exit 1 || exit "$1"
}

eval set -- "$(
  getopt -o h \
  --long help \
  --long magnet-i686: \
  --long magnet-dual: \
  -n "$(basename "$0")" -- "$@" || \
  echo usage
)"

tmp_dir="$(mktemp -d)"
cleanup() {
  if mountpoint -q "${tmp_dir}"; then
    sudo umount "${tmp_dir}"
  fi
  rm -rf --one-file-system "${tmp_dir}"
}
trap cleanup EXIT

while [ $# -gt 0 ]; do
  case "$1" in
    '--magnet-i686')
      if [ -s "${tmp_dir}/magnet.i686" ]; then
        printf 'Option %s given multiple times.\n' "$1"
        usage
      fi
      shift
      echo "$1" | \
        tr -d '\n' > \
        "${tmp_dir}/magnet.i686"
    ;;
    '--magnet-dual')
      if [ -s "${tmp_dir}/magnet.dual" ]; then
        printf 'Option %s given multiple times.\n' "$1"
        usage
      fi
      shift
      echo "$1" | \
        tr -d '\n' > \
        "${tmp_dir}/magnet.dual"
    ;;
    '--')
      shift
      break
    ;;
    *)
      >&2 printf 'Whoops, option "%s" is not yet implemented!\n' "$1"
      exit 42
    ;;
  esac
  shift
done

if [ $# -gt 0 ]; then
  >&2 echo 'Too many arguments.'
  exit 2
fi

(
  printf '    <div id="download-mirrors">\n'
  curl -Ss 'https://raw.githubusercontent.com/archlinux32/packages/master/core/pacman-mirrorlist/mirrorlist?'"$(
    head -c 24 /dev/urandom | \
      base64 -w0
  )" | \
    sed '
      0,/^$/d
      /^$/d
      /^## /{
        s|^## |\n        </ul>\n\n        <h5>|
        s|$|</h5>\n\n        <ul>\n|
        '"$(
          while read -r flag country; do
            printf \
              's|<h5>%s</h5>|<h5><span class="fam-flag fam-flag-%s" title="%s"></span> %s</h5>|\n' \
              "${country}" \
              "${flag}" \
              "${country}" \
              "${country}"
          done < \
            "${0%/*}/flag-names"
        )"'
      }
      /^#Server = /{
        s|^#Server = \(.*//\)\([^/]*\)\(/.*\)\$arch/\$repo$|'"$(
          printf \
            '            %s\\n' \
            '<li><a href="\1\2\3archisos/"' \
            '    title="Download from \1\2\3">\2</a></li>'
        )"'|
      }
    ' | \
    sed '
      0,/<\/ul>/d
    '
  printf '        </ul>\n\n'
  printf '    </div>\n'
) | \
  sed -i '
    :emptyLines
    /^\n*$/{
      N
      bemptyLines
    }
    /^\(\s*\n\)*\s*<div id="download-mirrors">$/{
      :a
      s|^.*</div>||
      tb
      $!N
      ba
      :b
      r /dev/stdin
    }
  ' "${website_dir}/download/index.html"

latest_iso_date="$(
  ls "${mirror_dir}/archisos" | \
    grep '^archlinux-[0-9.]\+-\(dual\|i.86\)\.iso$' | \
    sed 's@^archlinux-\([0-9.]\+\)-\(dual\|i.86\)\.iso$@\1@' | \
    sort -k1,1 -u | \
    tail -n1
)"

declare -A desc
desc['i686']='i686 only'
desc['dual']='dual bootable'

unset kernels
unset sizes
declare -A sizes
declare -A md5
declare -A sha512

for arch in "${!desc[@]}"; do
  iso="${mirror_dir}/archisos/archlinux-${latest_iso_date}-${arch}.iso"
  if [ ! -f "${iso}" ]; then
    >&2 echo "Can't find iso to arch ${arch}."
    exit 1
  fi
  sudo mount -o loop,ro "${iso}" "${tmp_dir}"
  kernels="$(
    printf '%s\n' ${kernels} $(
      grep '/linux-[0-9]' "${tmp_dir}/arch/pkglist."*".txt" | \
        grep -v 'pkglist\.x86_64\.txt:' | \
        sed '
          s|^\(.*:\)\?core/linux-||
          s|-[0-9]\+$||
        '
      ) | \
      sort -u
  )"
  sudo umount "${tmp_dir}"
  sizes["${arch}"]="$(
    printf 'scale=1; %s/1024/1024\n' "$(stat -c'%s' "${iso}")" | \
      bc
  )"
  md5["${arch}"]="$(
    grep "\s${iso##*/}\$" "${mirror_dir}/archisos/md5sums" | \
      awk '{print $1}'
  )"
  sha512["${arch}"]="$(
    grep "\s${iso##*/}\$" "${mirror_dir}/archisos/sha512sums" | \
      awk '{print $1}'
  )"
  sign_keys="$(
    printf '%s\n' ${sign_keys} $(
      gpg --status-fd=1 --verify "${iso}.sig" "${iso}" 2> /dev/null | \
        grep '^\[GNUPG:] VALIDSIG [0-9A-F]\+ ' | \
        cut -d' ' -f3
    ) | \
      sort -u
  )"
done

if [ $(echo "${kernels}" | grep -c '\S') -ne 1 ]; then
  >&2 echo 'Not exactly one kernel on the iso:'
  >&2 echo "${kernels}"
  exit 1
fi

if [ $(echo "${sign_keys}" | grep -c '\S') -ne 1 ]; then
  >&2 echo 'Not exactly one key used for signing the iso:'
  >&2 echo "'${sign_keys}'"
  exit 1
fi

if [ "${sign_keys}" != 'F2955C3B63EE4E421F30670A3B08EFC6BA974CFC' ] &&
  [ "${sign_keys}" != '248BF41F9BDD61D41D060AE774EDA3C6B06D0506' ] &&
  [ "${sign_keys}" != 'DE9F7688CACF04FEB81A6C590AEEC90755DA7B5A' ]; then
  >&2 echo "Unknown signing key '${sign_keys}'."
  exit 1
fi

values=(
  'Current Release' "${latest_iso_date}"
  'Included Kernel' "${kernels}"
  'PGP Key' '<a href="http://pgp.mit.edu/pks/lookup?search=0x'"${sign_keys}"'\&op=index">'"${sign_keys}"'</a>'
)
for arch in 'i686' 'dual'; do
  values+=(
    "ISO Size (${desc["${arch}"]})" "${sizes["${arch}"]} MB"
    "MD5 (${desc["${arch}"]})" "${md5["${arch}"]}"
    "SHA512 (${desc["${arch}"]})" "${sha512["${arch}"]}"
  )
done

sed -i "$(
  printf '/%s:/s|</strong>.*</li>|</strong> %s</li>|\n' "${values[@]}"
  printf '/archlinux-[0-9.]\+-%s\.iso\.sig/s@archlinux-[0-9.]\+-%s\.iso\.sig@archlinux-%s-%s.iso.sig@\n' \
    'i686' 'i686' "${latest_iso_date}" 'i686' \
    'dual' 'dual' "${latest_iso_date}" 'dual'
)
" \
  "${website_dir}/download/index.html"

for arch in "${!desc[@]}"; do
  if [ ! -s "${tmp_dir}/magnet.${arch}" ]; then
    continue
  fi
  if ! tr '&' '\n' < \
    "${tmp_dir}/magnet.${arch}" | \
    grep -qxF "dn=archlinux-${latest_iso_date}-${arch}.iso"; then
    >&2 printf 'Magnet link for %s is not for %s, skipping.\n' "${arch}" "archlinux-${latest_iso_date}-${arch}.iso"
    continue
  fi
  sed -i '
    /<li><a href="magnet:?.*-'"${arch}"'\.iso/ s/href="[^"]\+"/href="'"$(sed 's|&|\\&|g' "${tmp_dir}/magnet.${arch}")"'"/
    /title="Magnet link">Magnet link for \S\+ ('"${desc["${arch}"]}"')/ s/>Magnet link for \S\+ />Magnet link for '"${latest_iso_date}"' /
  ' "${website_dir}/download/index.html"
done