#!/bin/bash

mirror_base='/srv/arch-mirror/arch/arch/merged'

if [ ! -f '/tmp/packages' ]; then
  packages=$(
    ssh -p 22222 makepkg@141.35.51.219 '
      find -L "'"${mirror_base}"'" \
        -path '"'"'*testing/os/x86_64'"'"' \
        -prune \
        , \
        -name '"'"'*staging'"'"' \
        -prune \
        , \
        -name '"'"'any'"'"' \
        -prune \
        , \
        -name '"'"'*.db.tar.gz'"'"' \
        -printf '"'"'%%DBNAME%%\n%p\n\n'"'"' \
        -exec bsdtar -Oxf {} \; 2>/dev/null
    ' \
    | sed -n '
      /^%\(DBNAME\|NAME\|VERSION\|DEPENDS\|PROVIDES\)%$/,/^$/p
    ' \
    | sed '
      /^%NAME%$/ i %DUMP%
      $ a %DUMP%
    ' \
    | while read -r line; do
      if [ "${line}" = '%DBNAME%' ]; then
        read -r dbname
        read -r dummy
        if [ -n "${dummy}" ]; then
          >&2 printf 'Syntax error: %s\n' "${line}"
          exit 1
        fi
        continue
      fi
      if [ "${line}" = '%NAME%' ]; then
        read -r name
        read -r dummy
        if [ -n "${dummy}" ]; then
          >&2 printf 'Syntax error: %s\n' "${line}"
          exit 1
        fi
        continue
      fi
      if [ "${line}" = '%VERSION%' ]; then
        read -r version
        read -r dummy
        if [ -n "${dummy}" ]; then
          >&2 printf 'Syntax error: %s\n' "${line}"
          exit 1
        fi
        continue
      fi
      if [ "${line}" = '%PROVIDES%' ]; then
        while read -r provides; do
          if [ -z "${provides}" ]; then
            break
          fi
          printf 'provides %s %s %s %s\n' \
            "${dbname}" \
            "${name}" \
            "${version}" \
            "${provides}"
        done
        continue
      fi
      if [ "${line}" = '%DEPENDS%' ]; then
        while read -r depends; do
          if [ -z "${depends}" ]; then
            break
          fi
          printf 'depends %s %s %s %s\n' \
            "${dbname}" \
            "${name}" \
            "${version}" \
            "${depends}"
        done
        continue
      fi
      if [ "${line}" = '%DUMP%' ]; then
        if [ -n "${name}" ]; then
          printf 'provides %s %s %s %s=%s\n' \
            "${dbname}" \
            "${name}" \
            "${version}" \
            "${name}" \
            "${version}"
        fi
        continue
      fi
      >&2 printf 'Syntax error: %s\n' "${line}"
      exit 1
    done \
    | sed '
      s/\([<>=]\S\+\)-\S\+$/\1/
    '
  )
  
  printf '%s\n' "${packages}" > /tmp/packages
fi

packages=$(cat /tmp/packages)

packages=$(
  printf '%s\n' "${packages}" \
  | sed '
    s,^\(\S\+ \)\S\+/\([^/[:space:]]\+\)/\([^/[:space:]]\+\)\.db\.tar\.gz ,\1\2 \3 ,
    s/\([<=>]\S\+\)\?$/ \1/
  ' \
  | sed '
    s/ $/ X X/
    t
    s/\([<>]=\)\(\S\+\)$/\1 \2/
    t
    s/\([<>=]\)\(\S\+\)$/\1 \2/
    t
    w /dev/stderr
  '
)

matched_dependencies=$(
  join -1 1 -2 3 -o 1.1,2.1,2.2,2.5,1.3,2.4,1.2 <(
    printf '%s\n' "${packages}" \
    | sed -n '
      s/^provides \(\S\+\) \(\S\+ \)\{3\}/\1:/
      T
      p
    ' \
    | sort -k1,1
    # arch:install_target [=X] required_version
  ) <(
    printf '%s\n' "${packages}" \
    | sed -n '
      s/^depends \(\S\+\) archlinuxewe \(\S\+\) \(\S\+\) /\2 \3 \1:/
      T
      p
    ' \
    | sort -k3,3
    # provider_name provider_version arch:install_target version_comparison provided_version
  )
)
# arch:install_target depender_name depender_version required_version
#   provided_version required_version_comparison provided_version_comparison

version_comparisons=$(
  printf '%s\n' "${matched_dependencies}" \
  | grep -v ' X\( \S\+\)\?$' \
  | cut -d' ' -f4,5 \
  | sort -u
)
# required_version provided_version

version_comparisons=$(
  join -j 1 -o 1.2,2.2,2.3 \
  <(
    printf '%s\n' "${version_comparisons}" \
    | tr ' ' '\n' \
    | parallel -j100 -L2 vercmp \
    | cat -n
  ) <(
    printf '%s\n' "${version_comparisons}" \
    | cat -n
  ) \
  | sed '
    s/ \(\S\+\) \(\S\+\)$/ \1<->\2/
  ' \
  | sed '
    s/^-\S\+ /-1 /
    t
    /^0 /b
    s/^\S\+ /1 /
  '
)
# (-1|0|1) required_version<->provided_version

version_comparisons=$(
  {
    join -1 4 -2 2 <(
      printf '%s\n' "${matched_dependencies}" \
      | sed '
        s/ \(\S\+\) \(\S\+ \S\+ \S\+\)$/ \1<->\2/
      ' \
      | sort -k4,4
    ) <(
      printf '%s\n' "${version_comparisons}" \
      | sort -k2,2
    ) \
    | grep ' >=\? \S\+ -1$\| [<>]\?= \S\+ 0$\| <=\? \S\+ 1$' \
    | sed '
      s/^\(\S\+\)<->\S\+ /\1 /
    ' \
    | awk '{print $2" "$3" "$4" "$1" "$5}'
    printf '%s\n' "${matched_dependencies}" \
    | grep ' X\( \S\+\)\?$' \
    | awk '{print $1" "$2" "$3" "$4" "$6}'
  }
)
# arch:install_target depender_name depender_version required_version required_version_comparison

{
  printf '%s\n' "${matched_dependencies}" \
  | awk '{print $1" "$2" "$3" "$4" "$6}'
  printf '%s\n' "${version_comparisons}" \
  | sed p
} \
| sort \
| uniq -u \
| sed 's/^\(\S\+\):\(\S\+\) /\1 \2 /' \
| while read -r arch install_target depender_name depender_version required_version required_version_comparison; do
  printf '%s %s (%s) needs %s' \
    "${depender_name}" \
    "${depender_version}" \
    "${arch}" \
    "${install_target}"
  if [ "${required_version_comparison}" != 'X' ]; then
    printf '%s%s' \
      "${required_version_comparison}" \
      "${required_version}"
  fi
  printf '\n'
done \
| sort