#!/bin/bash

today=$(date +'%F')
stackdir="/etc/komodo/stacks"
backupdir="/backups"

services=()
readarray -d '' services < <(find "$stackdir" -maxdepth 1 -mindepth 1 -type d)

# Directories to backup.
volumes=(
  "/var/lib/docker/volumes"
  "/opt"
)

function stopServices() {
  echo "Stopping services..."
  for service in "${services[@]}"; do
    cd "$service" && docker compose stop
  done
}

function startServices() {
  echo "Restarting services..."
  for service in "${services[@]}"; do
    cd "$service" && docker compose up -d
  done
}

function copyStacks() {
  echo "Copying stack configuration..."
  local dir="$1/stacks"
  mkdir "$dir"
  for service in "${services[@]}"; do
    cp -r --parents "$service" "$dir"
  done
}

function copyVolumes() {
  echo "Copying volumes..."
  local dir="$1/volumes"
  mkdir "$dir"
  for volume in "${volumes[@]}"; do
    # copy only directories.
    find "$volume" -maxdepth 1 -mindepth 1 -type d -print0 |
      xargs -0 -I {} cp -r --parents "$volume" "{}"
  done
}

function backup() {
  echo "Creating backup..."
  tar -cvzf "/$today.tar.gz" "$1"
  cp -r "/$today.tar.gz" "$backupdir"
  # Cleanup temporary files.
  rm -rf "$1" "/$today.tar.gz"
}

function cleanBackups() {
  echo "Removing old backups..."
  # Remove backups older than 7 days.
  find "$backupdir" -maxdepth 1 -mindepth 1 -name "*.tar.gz" -mtime +7 -print0 |
    xargs -0 -I {} rm -rf "{}"
}

function main() {
  # stop services.
  stopServices

  # Create a temporary directory.
  local temp="/$today"
  mkdir "$temp"

  # copy stack configuration.
  copyStacks "$temp"

  # copy stack configuration.
  copyVolumes "$temp"

  # Create a tar to backup.
  backup "$temp"

  # Restart services.
  startServices

  # Remove backups older than 7 days.
  cleanBackups
}

main "$@"