#!/bin/bash
set -euo pipefail

ERROR_MSG=""
SUCCESS_MSG=""
RESTORE_OK=0
DA_USER=""

JOB_FILE="${1:-}"
if [ -z "$JOB_FILE" ] || [ ! -f "$JOB_FILE" ]; then
  echo "borg-restore: missing job file" >&2
  exit 1
fi

JOB_BASE="$(basename "$JOB_FILE")"
JOB_ID="${JOB_BASE%%.*}"

PLUGIN_DIR="/usr/local/directadmin/plugins/borg-restore"
LOG_DIR="${PLUGIN_DIR}/data/logs"
LOG_FILE="${LOG_DIR}/${JOB_ID}.log"

mkdir -p "$LOG_DIR"

fail() {
  local msg="$1"
  ERROR_MSG="$msg"
  echo "$msg" >> "$LOG_FILE"
}

format_restore_path() {
  local path="${1:-}"
  path="$(echo "$path" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//')"
  if [ -z "$path" ]; then
    echo ""
    return
  fi
  if [[ "$path" != /* ]]; then
    path="/$path"
  fi
  echo "$path"
}

append_missing_include_explanation() {
  if [ ! -f "$LOG_FILE" ]; then
    return
  fi
  if ! grep -qi "Include pattern '.*' never matched" "$LOG_FILE"; then
    return
  fi
  if grep -Fq "W przywracanej kopii zapasowej nie odnaleziono wskazanej ścieżki" "$LOG_FILE" || grep -Fq "The specified restore path was not found in the backup" "$LOG_FILE"; then
    return
  fi
  local label
  label="$(format_restore_path "${USERRESTOREPATH:-}")"
  local msg
  if [ "${USERLANG:-}" = "en" ]; then
    msg="The specified restore path"
  else
    msg="W przywracanej kopii zapasowej nie odnaleziono wskazanej ścieżki"
  fi
  if [ -n "$label" ]; then
    msg+=" (${label})"
  fi
  if [ "${USERLANG:-}" = "en" ]; then
    msg+=" was not found in the backup. Please try restoring from another archive that may contain those files."
  else
    msg+=". Prosimy spróbować przywrócić dane z innego archiwum, w którym te pliki mogły się znajdować."
  fi
  printf "\n%s\n" "$msg" >> "$LOG_FILE"
}

has_missing_include() {
  if [ ! -f "$LOG_FILE" ]; then
    return 1
  fi
  grep -qi "Include pattern '.*' never matched" "$LOG_FILE"
}

filter_log_content() {
  awk '{
    line=tolower($0);
    if (line ~ /permanently added/) next;
    if (line ~ /known host/) next;
    print;
  }'
}

secure_source_check() {
  local path="$1"
  local label="$2"
  local check_writable="${3:-1}"
  if [ -z "$path" ] || [ ! -e "$path" ]; then
    fail "Missing ${label}: ${path}"
    exit 1
  fi
  if [ -L "$path" ] || [ ! -f "$path" ]; then
    fail "Insecure ${label}: not a regular file (${path})"
    exit 1
  fi
  local owner_uid owner_name mode
  owner_uid="$(stat -c %u "$path" 2>/dev/null || true)"
  owner_name="$(stat -c %U "$path" 2>/dev/null || true)"
  mode="$(stat -c %a "$path" 2>/dev/null || true)"
  if [ -z "$owner_uid" ] || [ -z "$mode" ]; then
    fail "Unable to stat ${label}: ${path}"
    exit 1
  fi
  if [ "$owner_uid" != "0" ] && [ "$owner_uid" != "500" ] && [ "$owner_name" != "root" ] && [ "$owner_name" != "diradmin" ]; then
    fail "Insecure ${label} owner (${owner_name}:${owner_uid}): ${path}"
    exit 1
  fi
  mode=$((10#$mode))
  if [ "$check_writable" = "1" ] && (( (mode & 022) != 0 )); then
    fail "Insecure ${label} permissions (group/other writable): ${path}"
    exit 1
  fi
}

urlencode() {
  local input="$1"
  local hex out i
  hex="$(printf '%s' "$input" | od -An -tx1 | tr -d ' \n')"
  out=""
  for ((i=0; i<${#hex}; i+=2)); do
    out+="%${hex:i:2}"
  done
  printf '%s' "$out"
}

notify_user() {
  local code="$1"
  if [ -z "${DA_USER:-}" ]; then
    return
  fi
  local subject message
  if [ "$code" -eq 0 ] && [ "$RESTORE_OK" -eq 1 ]; then
    if [ "${USERLANG:-}" = "en" ]; then
      subject="BorgBackup restore completed successfully"
      message="Restore of ${USERRESTOREPATH:-} from ${REPONAME:-} completed."
    else
      subject="Przywracanie plików BorgBackup zakończone pomyślnie"
      message="${SUCCESS_MSG:-Przywracanie ${USERRESTOREPATH:-} z ${REPONAME:-} zakończone.}"
    fi
  else
    if [ "${USERLANG:-}" = "en" ]; then
      subject="BorgBackup restore error"
      message="Restore failed for ${USERRESTOREPATH:-} from ${REPONAME:-}."
    else
      subject="Błąd przywracania plików BorgBackup"
      if [ -n "$ERROR_MSG" ]; then
        message="Błąd przywracania: ${ERROR_MSG}"
      else
        message="Błąd przywracania ${USERRESTOREPATH:-} z ${REPONAME:-}."
      fi
    fi
    if [ -n "${LOG_FILE:-}" ] && [ -f "$LOG_FILE" ]; then
      local log_content
      log_content="$(cat "$LOG_FILE" | filter_log_content)"
      message="${message}\n\nLog:\n${log_content}"
    fi
  fi
  local task_queue="/usr/local/directadmin/data/task.queue"
  local users="select1%3D$(urlencode "$DA_USER")"
  local line="action=notify&value=users&subject=$(urlencode "$subject")&message=$(urlencode "$message")&users=${users}"
  printf "%s\n" "$line" >> "$task_queue"
}

on_exit() {
  local code="$1"
  notify_user "$code"
}
trap 'on_exit $?' EXIT

secure_source_check "$JOB_FILE" "job file" 0
# shellcheck disable=SC1090
source "$JOB_FILE"

DA_USER="${DA_USER:-}"
if [ -z "${DA_USER:-}" ]; then
  echo "Missing DA_USER in job file" >&2
  exit 1
fi

CONFIG_FILE="${PLUGIN_DIR}/plugin-settings.conf"

set_owner() {
  local path="$1"
  if [ -z "$path" ] || [ ! -e "$path" ]; then
    return
  fi
  if [ "$RESTORETYPE" = "mail" ]; then
    chown -R "${DA_USER}:mail" "$path"
  else
    chown -R "${DA_USER}:${DA_USER}" "$path"
  fi
}

is_true() {
  local v="${1:-}"
  v="$(printf '%s' "$v" | tr '[:upper:]' '[:lower:]')"
  case "$v" in
    1|true|yes|on) return 0 ;;
    *) return 1 ;;
  esac
}

if [ ! -f "$CONFIG_FILE" ]; then
  fail "Missing ${CONFIG_FILE}"
  exit 1
fi

secure_source_check "$CONFIG_FILE" "plugin-settings.conf"
# shellcheck disable=SC1090
source "$CONFIG_FILE"

BB_PATH="${BB_PATH:-/opt/bb}"
BORG_PATH="${BORG_PATH:-/usr/bin/borg}"
BORG_VARIABLES_FILE="${BORG_VARIABLES_FILE:-}"
WEB_RESTORE_LOCATION="${WEB_RESTORE_LOCATION:-/home/DA_USER/domains}"
MAIL_RESTORE_LOCATION="${MAIL_RESTORE_LOCATION:-/home/DA_USER/imap}"
BLOCK_RESTORE_OUTSIDE_LOCATION="${BLOCK_RESTORE_OUTSIDE_LOCATION:-TRUE}"
CLEAR_DOVECOT_INDEXES_AFTER_MERGE="${CLEAR_DOVECOT_INDEXES_AFTER_MERGE:-TRUE}"
RESTORE_PATH_MODE="${RESTORE_PATH_MODE:-dir}"

if [ -z "$BB_PATH" ]; then
  fail "BB_PATH is empty in plugin-settings.conf"
  exit 1
fi
if [ -z "$BORG_PATH" ]; then
  fail "BORG_PATH is empty in plugin-settings.conf"
  exit 1
fi

BBVARS_PATH="${BORG_VARIABLES_FILE:-}"
BBVARS_PATH="${BBVARS_PATH//DA_USER/${DA_USER}}"
if [ -z "$BBVARS_PATH" ]; then
  BBVARS_PATH="$BB_PATH"
  if [[ "$BBVARS_PATH" != *.sh ]]; then
    BBVARS_PATH="${BBVARS_PATH%/}/bbvars.sh"
  fi
fi

if [ ! -f "$BBVARS_PATH" ]; then
  fail "Missing ${BBVARS_PATH}"
  exit 1
fi

secure_source_check "$BBVARS_PATH" "bbvars.sh" 0
set -a
# shellcheck disable=SC1091
source "$BBVARS_PATH"
set +a

if [ -z "${REPO:-}" ]; then
  fail "Missing REPO in ${BBVARS_PATH}"
  exit 1
fi
if [ -n "${BORG_SSH_KEY:-}" ]; then
  if [ ! -f "${BORG_SSH_KEY}" ]; then
    fail "BORG_SSH_KEY is not a file: ${BORG_SSH_KEY}"
    exit 1
  fi
  export BORG_RSH="ssh -i \"${BORG_SSH_KEY}\""
fi

if [ -z "${REPONAME:-}" ] || [ -z "${USERRESTOREPATH:-}" ]; then
  fail "Missing REPONAME or USERRESTOREPATH in job file"
  exit 1
fi

RESTOREMODE="${RESTOREMODE:-location}"
RESTORETYPE="${RESTORETYPE:-web}"
if [ "$RESTORETYPE" != "mail" ]; then
  RESTORETYPE="web"
fi
if [ "$RESTORETYPE" = "mail" ]; then
  if [ "$RESTOREMODE" != "location" ] && [ "$RESTOREMODE" != "update" ]; then
    RESTOREMODE="update"
  fi
else
  if [ "$RESTOREMODE" != "location" ] && [ "$RESTOREMODE" != "overwrite" ]; then
    RESTOREMODE="location"
  fi
fi

RESTOREPATHMODE="${RESTOREPATHMODE:-$RESTORE_PATH_MODE}"
RESTOREPATHMODE="$(echo "$RESTOREPATHMODE" | tr '[:upper:]' '[:lower:]')"
RESTOREPATHMODE_FLAG="full"
if [ "$RESTOREPATHMODE" = "dir" ]; then
  RESTOREPATHMODE_FLAG="dir"
fi

TARGETPATH="${TARGETPATH:-}"
RESTORE_FULL="/${USERRESTOREPATH#/}"
WEB_BASE="${WEB_RESTORE_LOCATION//DA_USER/$DA_USER}"
MAIL_BASE="${MAIL_RESTORE_LOCATION//DA_USER/$DA_USER}"
BASE_LOCATION="$WEB_BASE"
if [ "$RESTORETYPE" = "mail" ]; then
  BASE_LOCATION="$MAIL_BASE"
fi
if [ -z "$BASE_LOCATION" ]; then
  fail "Base restore location is empty"
  exit 1
fi
TARGET_DIR="$BASE_LOCATION"
if [ -z "$TARGETPATH" ]; then
  TARGETPATH="$TARGET_DIR"
fi

BLOCK_FLAG="$(echo "$BLOCK_RESTORE_OUTSIDE_LOCATION" | tr '[:upper:]' '[:lower:]')"
if [ "$BLOCK_FLAG" = "1" ] || [ "$BLOCK_FLAG" = "true" ] || [ "$BLOCK_FLAG" = "yes" ] || [ "$BLOCK_FLAG" = "on" ]; then
  if [ -n "$BASE_LOCATION" ]; then
    BASE_LOCATION="${BASE_LOCATION%/}"
    if [[ "$RESTORE_FULL" != "$BASE_LOCATION" && "$RESTORE_FULL" != "$BASE_LOCATION/"* ]]; then
      fail "Restore path outside base location: ${RESTORE_FULL}"
      exit 1
    fi
  fi
fi

if [[ "$USERRESTOREPATH" == *".."* ]]; then
  fail "Invalid restore path (contains ..)"
  exit 1
fi

if [[ "$TARGETPATH" == *".."* ]]; then
  fail "Invalid target path (contains ..)"
  exit 1
fi

if [ "$RESTOREMODE" = "overwrite" ] || [ "$RESTOREMODE" = "update" ]; then
  TMP_BASE="/home/${DA_USER}/bb.tmp"
  RESTORE_BASE="${RESTORE_FULL##*/}"
  RESTORE_PARENT="${RESTORE_FULL%/*}"

  if [ -z "$RESTORE_BASE" ] || [ -z "$RESTORE_PARENT" ]; then
    fail "Nieprawidłowa ścieżka do przywrócenia."
    exit 1
  fi

  mkdir -p "$TMP_BASE"
  chown -R "${DA_USER}:${DA_USER}" "$TMP_BASE"

  rm -rf "${TMP_BASE}/${USERRESTOREPATH#/}" "${TMP_BASE}/${RESTORE_BASE}" 2>/dev/null || true

  cd "$TMP_BASE"
  set +e
  "$BORG_PATH" extract --progress "${REPO}::${REPONAME}" -- "${USERRESTOREPATH}" >> "$LOG_FILE" 2>&1
  EXIT_CODE=$?
  set -e
  append_missing_include_explanation

  if [ "$EXIT_CODE" -ne 0 ]; then
    if ! has_missing_include; then
      fail "Borg extract zakończył się błędem. Sprawdź logi w tabeli zdarzeń na stronie pluginu."
    fi
  else
    EXTRACTED_PATH="${TMP_BASE}/${USERRESTOREPATH#/}"
    TMP_ITEM="${TMP_BASE}/${RESTORE_BASE}"
    if [ ! -e "$EXTRACTED_PATH" ]; then
      fail "Nie znaleziono przywróconego katalogu: ${EXTRACTED_PATH}"
      EXIT_CODE=1
    else
      if [ -e "$TMP_ITEM" ]; then
        rm -rf "$TMP_ITEM" 2>/dev/null || true
      fi
      mv "$EXTRACTED_PATH" "$TMP_ITEM"

      if [ "$RESTOREMODE" = "update" ]; then
        if [ -e "$RESTORE_FULL" ]; then
          PRE_SUFFIX="$(date +%d-%m-%Y_%H%M%S)"
          PRE_NAME="${RESTORE_BASE}_przed_przywroceniem_${PRE_SUFFIX}"
          PRE_PATH="${RESTORE_PARENT}/${PRE_NAME}"
          mkdir -p "$PRE_PATH"
          set +e
          rsync -a "$RESTORE_FULL"/ "$PRE_PATH"/ >> "$LOG_FILE" 2>&1
          RSYNC_CODE=$?
          set -e
          if [ "$RSYNC_CODE" -ne 0 ]; then
            fail "Backup katalogu przed aktualizacją zakończył się błędem."
            EXIT_CODE=1
          fi
        else
          mkdir -p "$RESTORE_FULL"
        fi
        if [ "$EXIT_CODE" -eq 0 ]; then
          RSYNC_EXCLUDES=()
          if [ "$RESTORETYPE" = "mail" ]; then
            RSYNC_EXCLUDES+=(--exclude 'dovecot.index*')
            RSYNC_EXCLUDES+=(--exclude 'dovecot-uidlist')
            RSYNC_EXCLUDES+=(--exclude 'dovecot-uidvalidity')
            RSYNC_EXCLUDES+=(--exclude 'dovecot.list.index*')
            RSYNC_EXCLUDES+=(--exclude 'dovecot.list.log')
          fi
          set +e
          rsync -a "${RSYNC_EXCLUDES[@]}" "$TMP_ITEM"/ "$RESTORE_FULL"/ >> "$LOG_FILE" 2>&1
          RSYNC_CODE=$?
          set -e
          if [ "$RSYNC_CODE" -ne 0 ]; then
            fail "Aktualizacja danych przez rsync zakończyła się błędem."
            EXIT_CODE=1
          else
            if [ "$RESTORETYPE" = "mail" ] && is_true "$CLEAR_DOVECOT_INDEXES_AFTER_MERGE"; then
              find "$RESTORE_FULL" -type f \( -name 'dovecot.index*' -o -name 'dovecot-uidlist' -o -name 'dovecot-uidvalidity' -o -name 'dovecot.list.index*' -o -name 'dovecot.list.log' \) -delete >> "$LOG_FILE" 2>&1 || true
            fi
            set_owner "$RESTORE_FULL"
            rm -rf "$TMP_BASE"
            RESTORE_OK=1
            SUCCESS_MSG="Przywracanie ${USERRESTOREPATH} z ${REPONAME} zakończone. Pliki w ${RESTORE_FULL}."
            echo "$SUCCESS_MSG" >> "$LOG_FILE"
          fi
        fi
      else
        if [ -e "$RESTORE_FULL" ]; then
          PRE_SUFFIX="$(date +%d-%m-%Y_%H%M%S)"
          PRE_NAME="${RESTORE_BASE}_przed_przywroceniem_${PRE_SUFFIX}"
          PRE_PATH="${RESTORE_PARENT}/${PRE_NAME}"
          mv "$RESTORE_FULL" "$PRE_PATH"
        fi

        mkdir -p "$RESTORE_PARENT"
        mv "$TMP_ITEM" "$RESTORE_FULL"
        set_owner "$RESTORE_FULL"
        rm -rf "$TMP_BASE"
        RESTORE_OK=1
        SUCCESS_MSG="Przywracanie ${USERRESTOREPATH} z ${REPONAME} zakończone. Pliki w ${RESTORE_FULL}."
        echo "$SUCCESS_MSG" >> "$LOG_FILE"
      fi
    fi
  fi
else
  if [ ! -d "$TARGETPATH" ]; then
    mkdir -p "$TARGETPATH"
  fi
  if [ -d "$TARGETPATH" ] && [ "$(ls -A "$TARGETPATH" 2>/dev/null)" != "" ]; then
    fail "Target directory is not empty: ${TARGETPATH}"
    exit 1
  fi
  set_owner "$TARGETPATH"

  TARGET_DIR="$TARGETPATH"

  if [ "$RESTOREPATHMODE_FLAG" = "dir" ]; then
    IFS='/' read -r -a RESTORE_PARTS <<< "${USERRESTOREPATH#/}"
    PARTS_COUNT="${#RESTORE_PARTS[@]}"
    STRIP_COUNT=0
    if [ "$PARTS_COUNT" -gt 0 ]; then
      STRIP_COUNT=$((PARTS_COUNT - 1))
    fi

    cd "$TARGET_DIR"
    set +e
    "$BORG_PATH" extract --progress --strip-components "$STRIP_COUNT" "${REPO}::${REPONAME}" -- "${USERRESTOREPATH}" >> "$LOG_FILE" 2>&1
    EXIT_CODE=$?
    set -e
    append_missing_include_explanation

    if [ "$EXIT_CODE" -ne 0 ]; then
      if ! has_missing_include; then
        fail "Borg extract zakończył się błędem. Sprawdź logi w tabeli zdarzeń na stronie pluginu."
      fi
    else
      BASE_NAME="$(basename "${USERRESTOREPATH#/}")"
      DEST_PATH="${TARGET_DIR%/}/${BASE_NAME}"
      if [ -e "$DEST_PATH" ]; then
        set_owner "$DEST_PATH"
      fi
      RESTORE_OK=1
      SUCCESS_MSG="Przywracanie ${USERRESTOREPATH} z ${REPONAME} zakończone. Pliki w ${DEST_PATH}."
      echo "$SUCCESS_MSG" >> "$LOG_FILE"
    fi
  else
    cd "$TARGET_DIR"

    set +e
    "$BORG_PATH" extract --progress "${REPO}::${REPONAME}" -- "${USERRESTOREPATH}" >> "$LOG_FILE" 2>&1
    EXIT_CODE=$?
    set -e
    append_missing_include_explanation

    set_owner "$TARGET_DIR"

    if [ "$EXIT_CODE" -eq 0 ]; then
      RESTORE_OK=1
      SUCCESS_MSG="Przywracanie ${USERRESTOREPATH} z ${REPONAME} zakończone. Pliki w ${TARGET_DIR}."
      echo "$SUCCESS_MSG" >> "$LOG_FILE"
    else
      if ! has_missing_include; then
        fail "Borg extract zakończył się błędem. Sprawdź logi w tabeli zdarzeń na stronie pluginu."
      fi
    fi
  fi
fi

exit "$EXIT_CODE"