# -*- mode: sh; sh-basic-offset: 2; indent-tabs-mode: nil; -*-
# vim: set filetype=sh sw=2 sts=2 expandtab autoindent:
#
# restic script for backupninja
#

### GETCONF ###################################################################

setsection general

getconf testconnect yes
getconf nicelevel
getconf ionicelevel

getconf run_backup        "no"
getconf run_forget        "no"
getconf run_check         "no"
getconf run_prune         "no"

getconf cacert
getconf cache_dir
getconf cleanup_cache
getconf json
getconf limit_download
getconf limit_upload
getconf no_cache
getconf no_lock
getconf option
getconf password
getconf password_file
getconf quiet
getconf repository
getconf tls_client_cert

setsection s3

getconf aws_access_key_id
getconf aws_secret_access_key
getconf aws_session_token

setsection swift

getconf os_auth_url
getconf os_tenant_id
getconf os_tenant_name
getconf os_username
getconf os_password
getconf os_region_name

setsection b2

getconf b2_account_id
getconf b2_account_key

setsection azure

getconf azure_account_name
getconf azure_account_key

setsection gs

getconf google_project_id
getconf google_application_credentials

# Check that the ionicelevel is valid
if [ -n "$nicelevel" ] && { [ "$nicelevel" -lt -20 ] || [ "$nicelevel" -gt 19 ]; }; then
   fatal "The value of nicelevel is expected to be either empty or an integer from -20 to 19. Got: $nicelevel"
fi

# Check that the ionicelevel is valid
if [ -n "$ionicelevel" ] && echo "$ionicelevel" | grep -vq "^[0-7]$"; then
   fatal "The value of ionicelevel is expected to be either empty or an integer from 0 to 7. Got: $ionicelevel"
fi

### HELPERS ###################################################################

function export_debug {
  export "$1"="$2"
  debug "$1=${!1}"
}

function test_sftp_connection() {
  local remote
  local sftpport
  local output
  local ret

  remote=$1

  if echo "$remote" | grep -q ':[0-9]\+$'; then
    sftpport="-P $(echo $remote | @AWK@ -F ':' '{print $2}') "
    remote=$(echo $remote | @AWK@ -F ':' '{print $1}')
  fi

  debug "echo | sftp -o PasswordAuthentication=no ${sftpport}${remote}"
  output=$(echo | sftp -o PasswordAuthentication=no ${sftpport}${remote})
  ret=$?

  if [ $ret -eq 0 ]; then
    debug "Connection test to SFTP backend ${remote} succeeded."
  else
    debug $output
    fatal "Failed connecting to SFTP backend at ${remote}."
  fi
}

function test_rest_connection() {
  local remote
  local output
  local ret

  local remote=$1

  if [ ! -x $(which wget) ]; then
    error "Unable to test REST connection, wget executable not found!"
    return
  fi

  debug "wget --tries=1 --method=HEAD \"${remote}/config\""
  output=$(wget --tries=1 --method=HEAD "${remote}/config")
  ret=$?

  if [ $ret -eq 0 ]; then
    debug "Connection test to REST backend at ${remote} succeeded."
  elif [ $ret -eq 8 ]; then
    debug $output
    fatal "REST backend at ${remote} returned an error, repository may not be created."
  else
    debug $output
    fatal "Failed connecting to REST backend at ${remote}."
  fi
}

### PRE-COMMANDS ##############################################################

[ -n "$nicelevel" ] && \
  precmd+="nice -n $nicelevel "

[ -n "$ionicelevel" ] && \
  precmd+="ionice -c2 -n $ionicelevel "



### GLOBAL OPTIONS ############################################################

[ -z "$repository" ] && \
  fatal "The repository option must be set."

[ -z "$password" ] && [ -z "$password_file" ] && \
    fatal "The password must be set by option 'password' or 'password_file'."

[ -n "$repository" ] && \
  cmd_global_options+="--repo $repository "

[ -n "$password" ] && \
  export_debug RESTIC_PASSWORD "$password"

[ -n "$password_file" ] && \
  cmd_global_options+="--password-file $password_file "

[ -n "$cacert" ] && \
  cmd_global_options+="--cacert $cacert "

[ -n "$cache_dir" ] && \
  cmd_global_options+="--cache-dir $cache_dir "

[ -n "$cleanup_cache" ] && \
  cmd_global_options+="--cleanup-cache "

[ -n "$json" ] && \
  cmd_global_options+="--json "

[ -n "$limit_download" ] && \
  cmd_global_options+="--limit-download $limit_download "

[ -n "$limit_upload" ] && \
  cmd_global_options+="--limit-upload $limit_upload "

[ -n "$no_cache" ] && \
  cmd_global_options+="--no-cache "

[ -n "$no_lock" ] && \
  cmd_global_options+="--no-lock "

[ -n "$option" ] && \
  cmd_global_options+="$(for i in "${option[@]}"; do echo "--option $i "; done)"

[ -n "$quiet" ] && \
  cmd_global_options+="--quiet "

[ -n "$tls_client_cert" ] && \
  cmd_global_options+="--tls-client-cert $tls_client_cert "

### REPOSITORY ################################################################

# SFTP repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "sftp" ]; then

  # connection test
  if [ "$testconnect" = "yes" ] || [ "$test" -eq 1 ]; then

    if echo "$repository" | grep -q '^sftp://'; then
      remote=$(echo "$repository" | @AWK@ -F '//' '{print $2}')
    elif echo "$repository" | grep -q '^sftp:'; then
      remote=$(echo "$repository" | @AWK@ -F ':' '{print $2}')
    fi

    [ -n "$remote" ] || fatal "Unable to parse SFTP repository URL ${repository}."
    test_sftp_connection $remote

  fi

fi

# REST Server repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "rest" ]; then

  # connection test
  if [ "$testconnect" = "yes" ] || [ "$test" -eq 1 ]; then

    remote="${repository#rest:}"
    test_rest_connection $remote

  fi

fi

# Amazon S3 repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "s3" ]; then

  ( [ -z "$aws_access_key_id" ] || [ -z "$aws_secret_access_key" ] ) && \
    fatal "Missing some S3 credentials."

  export_debug AWS_ACCESS_KEY_ID "$aws_access_key_id"
  export_debug AWS_SECRET_ACCESS_KEY "$aws_secret_access_key"
  [ -n "$aws_session_token" ] && \
    export_debug AWS_SESSION_TOKEN "$aws_session_token"

fi

# OpenStack Swift repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "swift" ]; then

  (
    [ -z "$os_auth_url" ] || [ -z "$os_tenant_id" ] || [ -z "$os_tenant_name" ] || \
    [ -z "$os_username" ] || [ -z "$os_password" ] || [ -z "$os_region_name" ]
  ) && \
    fatal "Missing some Swift credentials."

  export_debug OS_AUTH_URL "$os_auth_url"
  export_debug OS_TENANT_ID "$os_tenant_id"
  export_debug OS_TENANT_NAME "$os_tenant_name"
  export_debug OS_USERNAME "$os_username"
  export_debug OS_PASSWORD "$os_password"
  export_debug OS_REGION_NAME "$os_region_name"

fi

# Backblaze B2 repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "b2" ]; then

  ( [ -z "$b2_account_id" ] || [ -z "$b2_account_key" ] ) && \
    fatal "Missing some B2 credentials."

  export_debug B2_ACCOUNT_ID "$b2_account_id"
  export_debug B2_ACCOUNT_KEY "$b2_account_key"

fi

# Microsoft Azure Blob Storage repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "azure" ]; then

  ( [ -z "$azure_account_name" ] || [ -z "$azure_account_key" ] ) && \
    fatal "Missing some Azure credentials."

  export_debug AZURE_ACCOUNT_NAME "$azure_account_name"
  export_debug AZURE_ACCOUNT_KEY "$azure_account_key"

fi

# Google Cloud Storage repository
if [ "$(echo "$repository" | @AWK@ -F ':' '{print $1}')" == "gs" ]; then

  ( [ -z "$google_project_id" ] || [ -z "$google_application_credentials" ] ) && \
    fatal "Missing some Google credentials."

  export_debug GOOGLE_PROJECT_ID "$google_project_id"
  export_debug GOOGLE_APPLICATION_CREDENTIALS "$google_application_credentials"

fi

### BACKUP #####################################################################

if [ "$run_backup" == "yes" ]; then

  setsection backup

  getconf include "/"
  getconf exclude "/dev /lost+found /media /mnt /proc /run /sys /tmp /var/cache /var/lock /var/spool /var/run /var/tmp"
  getconf exclude_caches
  getconf exclude_file
  getconf exclude_if_present
  getconf files_from
  getconf force
  getconf hostname
  getconf one_file_system
  getconf parent
  getconf tag
  getconf time
  getconf with_atime

  # prevent bash from expanding glob
  set -f

  [ -z "$include" ] && [ -z "$files_from" ] && \
    fatal "No files or directories specified for backup."

  [ -n "$include" ] && \
    cmd_options+="$(for i in $include; do echo "$i "; done)"

  [ -n "$files_from" ] && \
    cmd_options+="$(for i in $files_from; do echo "--files-from $i "; done)"

  [ -d "$repository" ] && \
    cmd_options+="--exclude $repository "

  [ -n "$exclude" ] && \
    cmd_options+="$(for i in $exclude; do echo "--exclude $i "; done)"

  [ "$exclude_caches" == "yes" ] && \
    cmd_options+="--exclude-caches "

  [ -n "$exclude_file" ] && \
    cmd_options+="$(for i in $exclude_file; do echo "--exclude-file $i "; done)"

  [ -n "$exclude_if_present" ] && \
    cmd_options+="$(for i in $exclude_if_present; do echo "--exclude-if-present $i "; done)"

  [ "$force" == "yes" ] && \
    cmd_options+="--force "

  [ -n "$hostname" ] && \
    cmd_options+="--hostname $hostname "

  [ -n "$one_file_system" ] && \
    cmd_options+="--one-file-system "

  [ -n "$parent" ] && \
    cmd_options+="--parent $parent "

  [ -n "$tag" ] && \
    cmd_options+="$(for i in $tag; do echo "--tag=$i "; done)"

  [ -n "$time" ] && \
    cmd_options+="--time $time "

  [ "$with_atime" == "yes" ] && \
    cmd_options+="--with_atime "

  # format command
  cmd="restic backup"
  execstr="${precmd}${cmd} ${cmd_global_options//$'\n'}${cmd_options//$'\n'}"

  # debug
  debug "executing restic backup"
  debug "$execstr"

  # execute
  if [ $test -eq 1 ]; then
    info "Test mode enabled, skipping restic backup."
  else
    info "Creating new backup snapshot."
    output=$($execstr 2>&1)
    ret=$?
    if [ $ret -eq 0 ]; then
      debug $output
      info "Restic backup successful."
    else
      error $output
      fatal "Restic backup failed."
    fi
  fi

  # set bash orginal globbing behavior
  set +f

  debug "Unsetting variables"
  unset cmd_options
  unset execstr
  unset output
  unset ret

fi

### FORGET #####################################################################

if [[ "$run_forget" == "yes" ]]; then

  setsection forget

  getconf keep_last "7"
  getconf keep_hourly
  getconf keep_daily
  getconf keep_weekly
  getconf keep_monthly
  getconf keep_yearly
  getconf keep_within
  getconf keep_tag
  getconf host
  getconf tag
  getconf path
  getconf compact
  getconf group_by
  getconf dry_run
  getconf prune

  [ -n "$keep_last" ] && \
    cmd_options+="--keep-last $keep_last "

  [ -n "$keep_hourly" ] && \
    cmd_options+="--keep-hourly $keep_hourly "

  [ -n "$keep_daily" ] && \
    cmd_options+="--keep-daily $keep_daily "

  [ -n "$keep_weekly" ] && \
    cmd_options+="--keep-weekly $keep_weekly "

  [ -n "$keep_monthly" ] && \
    cmd_options+="--keep-monthly $keep_monthly "

  [ -n "$keep_yearly" ] && \
    cmd_options+="--keep-yearly $keep_yearly "

  [ -n "$keep_within" ] && \
    cmd_options+="--keep-within $keep_within "

  [ -n "$keep_tag" ] && \
    cmd_options+="$(for i in $keep_tag; do echo "--keep-tag=$i "; done)"

  [ -n "$host" ] && \
    cmd_options+="--host $host "

  [ -n "$tag" ] && \
    cmd_options+="$(for i in $tag; do echo "--tag=$i "; done)"

  [ -n "$path" ] && \
    cmd_options+="$(for i in $path; do echo "--path=$i "; done)"

  [ -n "$compact" ] && \
    cmd_options+="--compact "

  [ -n "$group_by" ] && \
    cmd_options+="--group-by $group_by "

  [ -n "$dry_run" ] && \
    cmd_options+="--dry-run "

  [ -n "$prune" ] && \
    cmd_options+="--prune "

  # format command
  cmd="restic forget"
  execstr="${precmd}${cmd} ${cmd_global_options//$'\n'}${cmd_options//$'\n'}"

  # debug
  debug "executing restic forget"
  debug "$execstr"

  # execute
  if [ $test -eq 1 ]; then
    info "Test mode enabled, skipping restic forget."
  else
    info "Removing old snapshots based on defined retention policy."
    output=$($execstr 2>&1)
    ret=$?
    if [ $ret -eq 0 ]; then
      debug $output
      info "Restic forget successful."
    else
      error $output
      fatal "Restic forget failed."
    fi
  fi

  debug "Unsetting variables"
  unset cmd_options
  unset execstr
  unset output
  unset ret

fi

### CHECK ######################################################################

if [ "$run_check" == "yes" ]; then

  setsection check

  getconf check_unused
  getconf read_data
  getconf read_data_subset
  getconf with_cache

  [ -n "$check_unused" ] && \
    cmd_options+="--check-unused "

  [ -n "$read_data" ] && \
    cmd_options+="--read-data "

  [ -n "$read_data_subset" ] && \
    cmd_options+="--read-data-subset $read_data_subset "

  [ -n "$with_cache" ] && \
    cmd_options+="--with-cache "

  # format command
  cmd="restic check"
  execstr="${precmd}${cmd} ${cmd_global_options//$'\n'}${cmd_options//$'\n'}"

  # debug
  debug "executing restic check"
  debug "$execstr"

  # execute
  if [ $test -eq 1 ]; then
    info "Test mode enabled, skipping restic check."
  else
    info "Checking repository integrity and consistency."
    output=$($execstr 2>&1)
    ret=$?
    if [ $ret -eq 0 ]; then
      debug $output
      info "Restic check successful."
    else
      error $output
      fatal "Restic check failed."
    fi
  fi

  debug "Unsetting variables"
  unset cmd_options
  unset execstr
  unset output
  unset ret

fi

### PRUNE ######################################################################

if [ "$run_prune" == "yes" ]; then

  # format command
  cmd="restic prune"
  execstr="${precmd}${cmd} ${cmd_global_options//$'\n'}"

  # debug
  debug "executing restic prune"
  debug "$execstr"

  # execute
  if [ $test -eq 1 ]; then
    info "Test mode enabled, skipping restic prune."
  else
    info "Removing unreferenced data from repository."
    output=$($execstr 2>&1)
    ret=$?
    if [ $ret -eq 0 ]; then
      debug $output
      info "Restic prune successful."
    else
      error $output
      fatal "Restic prune failed."
    fi
  fi

  debug "Unsetting variables"
  unset execstr
  unset output
  unset ret

fi

### CLEAN UP ###################################################################

debug "Unsetting environment variables"
unset RESTIC_PASSWORD
unset AWS_ACCESS_KEY_ID
unset AWS_SECRET_ACCESS_KEY
unset AWS_SESSION_TOKEN
unset OS_AUTH_URL
unset OS_TENANT_ID
unset OS_TENANT_NAME
unset OS_USERNAME
unset OS_PASSWORD
unset OS_REGION_NAME
unset B2_ACCOUNT_ID
unset B2_ACCOUNT_KEY
unset AZURE_ACCOUNT_NAME
unset AZURE_ACCOUNT_KEY
unset GOOGLE_PROJECT_ID
unset GOOGLE_APPLICATION_CREDENTIALS
unset cmd_global_options

return 0