#!/usr/bin/env bash

set -eo pipefail

DOCKER_VOLUMES="sentry-postgres sentry-data sentry-redis sentry-zookeeper sentry-kafka sentry-clickhouse sentry-symbolicator"
BACKUP_BASE_DIR="."
BACKUP_DIR_PREFIX="backup-"
CONTAINER_VOLUME_BASE_DIR="/volumes"
CONTAINER_BACKUP_BASE_DIR="/backup"
SCRIPT_DIR="$( cd "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"
SCRIPT_NAME="sentry-util.sh"

function_exists() {
  set +e
  declare -f -F $1 > /dev/null
  local ret=$?
  set -e
  echo $ret
}

function backup {
  [ ! -z "$BACKUP_BASE_DIR" ] && mkdir -p "$BACKUP_BASE_DIR"

  local today=$(date +%Y%m%d)
  local backup_dir=$(readlink -f "$BACKUP_BASE_DIR/$BACKUP_DIR_PREFIX$today")

  mkdir -p "$backup_dir"

  echo "Creating backup directory '$backup_dir'..."

  run_container "backup-volumes" "-v $backup_dir:$CONTAINER_BACKUP_BASE_DIR"
}

function restore {
  local backup_date=$1

  if [ -z "$backup_date" ]; then
    echo 1>&2 "Vous devez spécifier une date au format YYYYMMDD en premier argument."
    exit 1
  fi

  local backup_dir=$(readlink -f "$BACKUP_BASE_DIR/$BACKUP_DIR_PREFIX$backup_date")

  if [ ! -d "$backup_dir" ]; then
    echo 1>&2 "Le dossier de sauvegarde '$backup_dir' n'existe pas."
    exit 1
  fi

  run_container "restore-volumes" "-v $backup_dir:$CONTAINER_BACKUP_BASE_DIR"
}

function rotate {
  local retention=${1:-2}
  local backup_dirs=( $(find -maxdepth 1 -type d -name "$BACKUP_DIR_PREFIX*" -printf "%f\n" | sort -r) )
  echo "Rotating backups (retention: $retention)"
  echo "Found ${#backup_dirs[@]} backup(s)"
  for d in ${backup_dirs[@]:$retention}; do
    local abs_dir="$(readlink -f $d)"
    echo "Deleting backup '$abs_dir'"
    rm -rf "$abs_dir"
  done
}

function run_container {
  local docker_cmd="$1"
  local additional_docker_args="$2"

  local volume_args=""
  for volume in $DOCKER_VOLUMES; do
    volume_args="$volume_args -v $volume:$CONTAINER_VOLUME_BASE_DIR/$volume"
  done

  docker run --rm \
    $volume_args \
    $additional_docker_args \
    -v "$SCRIPT_DIR/$SCRIPT_NAME:/usr/local/bin/$SCRIPT_NAME" \
    bash:5 \
    /usr/local/bin/$SCRIPT_NAME $docker_cmd
}

function backup-volumes {
  for volume in $DOCKER_VOLUMES; do
    local volume_dir="$CONTAINER_VOLUME_BASE_DIR/$volume"
    echo "Copying volume '$volume' data..."
    rm -rf "$CONTAINER_BACKUP_BASE_DIR/$volume"
    cp -aR "$volume_dir" "$CONTAINER_BACKUP_BASE_DIR/"
  done
}

function restore-volumes {
  for volume in $DOCKER_VOLUMES; do
    local volume_dir="$CONTAINER_VOLUME_BASE_DIR/$volume"
    echo "Restoring volume '$volume' data..."
    rm -rf "$volume_dir/"*
    cp -aR "$CONTAINER_BACKUP_BASE_DIR/$volume/"* "$volume_dir/"
  done
}

function main {
  local command=$1
  local command_args=${@:2}
  
  if [ "$(function_exists $command)" == "1" ]; then
    echo 1>&2 "La commande '$command' n'existe pas."
    exit 1
  fi

  $command $command_args
}

main $@