#!/bin/sh

. "${0%/*}/../conf/default.conf"

# Create a lock file.

if [ $# -eq 0 ]; then
  broken="$(
    ls "${work_dir}/package-states" | \
      grep '\.broken$'
  )"
  broken="$(
    echo "${broken}" | \
      sed 's|\(\.[^.]\+\)\{4\}$||'
  )"
  "$0" ${broken}
  exit $?
fi

if ps ax | \
  grep -v grep | \
  grep -v "^\s*$$\s" | \
  grep -wF "$0$(
    printf ' %s' "$@"
  )"; then

  >&2 echo $$
  >&2 echo 'I was running already.'
  exit
fi

exec 9> "${work_dir}/${0##*/}.lock"
if ! flock -n 9; then
  echo 'Cannot get lock.'
  exit
fi

tmp_dir="$(mktemp -d)"
trap 'rm -rf --one-file-system "${tmp_dir}"' EXIT

sort -u "${work_dir}/build-order" | \
  grep -v '^\(\S\+\) \1$' | \
  grep '^\S\+ \S\+$' > \
  "${tmp_dir}/original-build-order"

(
  sort -k1,1 "${tmp_dir}/original-build-order" | \
    join -1 1 -2 1 -o 1.1,1.2 - "${work_dir}/build-list.sorted-by-package"
  sort -k2,2 "${tmp_dir}/original-build-order" | \
    join -1 2 -2 1 -o 1.1,1.2 - "${work_dir}/build-list.sorted-by-package"
) | \
  sort -u | \
  sponge "${tmp_dir}/original-build-order"

ls "${work_dir}/package-infos" | \
  sed 's|\(\.[^.]\+\)\{4\}$||' | \
  sort -u > \
  "${tmp_dir}/known-packages"

ls "${work_dir}/package-infos" | \
  grep '\.groups$' | \
  sed "s|^|${work_dir}/package-infos/|" | \
  xargs -r cat | \
  sort -u > \
  "${tmp_dir}/known-groups"

ls "${work_dir}/package-infos" | \
  grep '\.packages$' | \
  while read -r pf; do
    grep -vxF "${pf%.*.*.*.*}" "${work_dir}/package-infos/${pf}" | \
      xargs -r printf "${pf%.*.*.*.*} %s\n" >> \
      "${tmp_dir}/known-split-packages"
  done

for target_package in "$@"; do

  rm -f \
    "${tmp_dir}/knots" \
    "${tmp_dir}/build-order"
  touch "${tmp_dir}/knots"

  output="${graphs_directory}/${target_package}.png"

  (
    grep " $(str_to_regex "${target_package}")\$" "${tmp_dir}/original-build-order" || \
      true
    printf '0 target-package %s\n' "${target_package}" >> \
      "${tmp_dir}/knots"
  ) | \
    sort -u > \
    "${tmp_dir}/build-order"

  last_sum=''
  current_sum="$(sha512sum "${tmp_dir}/build-order")"
  while ! [ "${last_sum}" = "${current_sum}" ]; do

    last_sum="${current_sum}"

    while read -r s t; do
      printf '%s %s\n' "${s}" "${t}"
      grep -h " $(str_to_regex "${s}")\$" \
        "${tmp_dir}/original-build-order" \
        "${tmp_dir}/known-split-packages" \
        "${tmp_dir}/known-groups" || \
        true
    done < \
      "${tmp_dir}/build-order" | \
      sort -u | \
      sponge "${tmp_dir}/build-order"

    current_sum="$(sha512sum "${tmp_dir}/build-order")"

  done

  tr ' ' '\n' < \
    "${tmp_dir}/build-order" | \
    sort -u | \
    join -j 1 - "${work_dir}/build-list.sorted-by-package" | \
    while read pkg rev mod_rev repo; do
      if [ -f "${work_dir}/package-states/${pkg}.${rev}.${mod_rev}.${repo}.broken" ]; then
        printf '1 broken-build-list-package %s\n' "${pkg}"
      else
        printf '2 build-list-package %s\n' "${pkg}"
      fi
    done >> \
    "${tmp_dir}/knots"

  (
    awk '{print $2}' "${tmp_dir}/known-split-packages" | \
      sort -u
    tr ' ' '\n' < \
      "${tmp_dir}/build-order" | \
      sort -u
  ) | \
    sort | \
    uniq -d | \
    xargs -r printf '3 split-package %s\n' >> \
    "${tmp_dir}/knots"

  (
    cat "${tmp_dir}/known-packages"
    tr ' ' '\n' < \
      "${tmp_dir}/build-order" | \
      sort -u
  ) | \
    sort | \
    uniq -d | \
    xargs -r printf '4 package %s\n' >> \
    "${tmp_dir}/knots"

  (
    cat "${tmp_dir}/known-groups"
    tr ' ' '\n' < \
      "${tmp_dir}/build-order" | \
      sort -u
  ) | \
    sort | \
    uniq -d | \
    xargs -r printf '5 group %s\n' >> \
    "${tmp_dir}/knots"

  tr ' ' '\n' < \
    "${tmp_dir}/build-order" | \
    sort -u | \
    xargs -r printf '100 unknown %s\n' >> \
    "${tmp_dir}/knots"

  printf '%s\n' \
    'digraph dependencies {' \
    '  fontname=dejavu;' > \
    "${tmp_dir}/input"

  sort -k3,3 -k1n,1 "${tmp_dir}/knots" | \
    uniq -f2 | \
    while read -r num what who; do
      if [ "${what}" = 'broken-build-list-package' ]; then
        color='#ff0000'
      elif [ "${what}" = 'build-list-package' ]; then
        color='#800000'
      elif [ "${what}" = 'target-package' ]; then
        color='#00ff00'
      elif [ "${what}" = 'package' ]; then
        color='#000000'
      elif [ "${what}" = 'split-package' ]; then
        color='#808080'
      elif [ "${what}" = 'group' ]; then
        color='#0000ff'
      else
        color='#ff80ff'
      fi
      printf '  "%s" [fontcolor="%s"];\n' "${who}" "${color}"
    done >> \
    "${tmp_dir}/input"

  xargs -rn2 printf '  "%s" -> "%s";\n' < \
    "${tmp_dir}/build-order" | \
    sort -u >> \
    "${tmp_dir}/input"

  printf '%s\n' \
    '}' >> \
    "${tmp_dir}/input"

  line_count="$(wc -l < "${tmp_dir}/input")"
  if [ "${line_count}" -gt 500 ]; then
    >&2 printf 'Skipping graph for "%s" - would be too big (%d).\n' \
      "${target_package}" \
      "${line_count}"
    continue
  fi
  printf 'small enough (%s): %d\n' \
    "${target_package}" \
    "${line_count}"

  touch "${output}"
  chmod 644 "${output}"

  dot -Tpng -o "${output}" "${tmp_dir}/input" || continue

done

rm "${work_dir}/${0##*/}.lock"