#!/bin/bash

. "${0%/*}/common"

if [ -z "$(git -C "${git_dir}" diff)" ]; then
  exit
fi

find_vcfs \
| while read -r file; do
  if [ ! -f "${file}" ]; then
    >&2 printf 'File "%s" is in git, but not in the worktree.\n' "${file##*/}"
    exit 1
  fi
  if ! git -C "${git_dir}" archive HEAD -- "${file##*/}" >/dev/null; then
    >&2 printf 'File "%s" is in the worktree but not in git.\n' "${file##*/}"
    exit 1
  fi
  if ! git -C "${git_dir}" archive HEAD -- "${file##*/}" \
  | tar -Ox \
  | diff -q - "${file}"; then
    >&2 printf 'File "%s" was changed relative to git.\n' "${file##*/}"
    exit 1
  fi
done

print_cnt() {
  printf 'BEGIN:VCARD\n'
  printf 'VERSION:3.0\n'
  for key in "${keys[@]}"; do
    eval 'value="${'"$1${key}"'}"'
    if [ -n "${value}" ]; then
      printf '%s:%s\n' "${key}" "${value}"
    fi
  done
  printf 'END:VCARD\n'
}

read_line() {
  local line
  read -r line
  for key in "${alpine_keys[@]}"; do
    eval "${1}${key}"'="${line%%'"$(printf '\t')"'*}"'
    eval 'line="${line#${'"${1}${key}"'}}"'
    line="${line#$(printf '\t')}"
  done
}

sed -i '
  /^#/d
' "${git_dir}"'/addressbook'

last_uids=()
git -C "${git_dir}" diff -U0 -- addressbook \
| sed '
  1,/^+++/d
  $ s#$#\n@@ #
' \
| while read line; do
  case "${line}" in
    '@@ '*)
      for last_uid in "${last_uids[@]}"; do
        sed -i '/^'"${last_uid}"'\s/d' "${git_dir}/uids"
        rm "${git_dir}/${last_uid}.vcf"
      done
      last_uids=()
      removals=false
    ;;
    '+'*)
      newUID="${last_uids[${#last_uids[@]}]}"
      mapfile -t last_uids < <(
        printf '%s\n' "${last_uids[@]}" \
        | sed '$d'
      )
      read_line 'new' < <(
        printf '%s\n' "${line#+}"
      )
      newREV=$(
        date -u -Iseconds \
        | sed 's@+00:00$@Z@'
      )
      if [ -z "${newUID}" ]; then
        if ${removals}; then
          >&2 printf 'There were more addresses added than removed.\n'
          exit 1
        fi
        newUID=$(uuidgen)
        printf '%s\t%s\n' "${newUID}" "${line#+}" \
        >> "${git_dir}/uids"
        print_cnt 'new' > "${git_dir}/${newUID}.vcf"
      else
        read_line 'old' < <(
          sed '
            s/^'"${newUID}"'\t//
            t
            d
          ' "${git_dir}/uids"
        )
        sed -i '
          /^'"${newUID}"'\t/ {
            i '"${newUID}$(printf '\t')${line#+}"'
            d
          }
        ' "${git_dir}/uids"
        for key in "${alpine_keys[@]}"; do
          if eval '[ "${old'"${key}"'}" != "${new'"${key}"'}" ]'; then
            for insert in "${key}:" 'VERSION:' 'BEGIN:VCARD$' ''; do
              if [ -z "${insert}" ]; then
                >&2 printf 'Cannot find any place to insert into "%s".\n' "${uid}.vcf"
                exit 1
              fi
              if ! grep -q '^'"${insert}" "${git_dir}/${uid}.vcf"; then
                continue
              fi
              if [ "${insert}" = "${key}:" ]; then
                delete_command='d'
              else
                delete_command=''
              fi
              eval 'value="${new'"${key}"'}"'
              if [ -z "${value}" ]; then
                insert_command=''
              else
                insert_command='a '"${key}"':'"${value}"
              fi
              sed -i '
                /^'"${key}"'/ {
                  '"${insert_command}"'
                  '"${delete_command}"'
                }
              ' "${git_dir}/${uid}.vcf"
              break
            done
          fi
        done
      fi
    ;;
    '-'*)
      removals=true
      if num=$(
        sed 's@^\S\+ @@' "${git_dir}/uids" \
        | grep -nxF "${line#-}"
      ); then
        last_uid=$(
          sed -n '
            '"${num}"' {
              s@\s.*$@@
              p
            }'
        )
      else
        >&2 printf 'cannot find line "%s" for removal\n' "${line#-}"
        exit 1
      fi
      last_uids=(
        "${last_uids[@]}"
        "${last_uid}"
      )
    ;;
  esac
done