#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
ENV_FILE="${KOPIA_ENV_FILE:-/opt/kopia/kopia.env}"

if [[ -f "$ENV_FILE" ]]; then
  # shellcheck disable=SC1090
  source "$ENV_FILE"
fi

KOPIA_CONFIG_FILE="${KOPIA_CONFIG_FILE:-/opt/kopia/repository.config}"
KOPIA_CACHE_DIRECTORY="${KOPIA_CACHE_DIRECTORY:-/opt/kopia/cache}"
KOPIA_LOG_DIR="${KOPIA_LOG_DIR:-/opt/kopia/logs}"
BACKUP_STAGING_DIR="${BACKUP_STAGING_DIR:-/opt/kopia/staging}"
BACKUP_PATHS_FILE="${BACKUP_PATHS_FILE:-$SCRIPT_DIR/backup-paths.txt}"
KOPIA_EXCLUDES_FILE="${KOPIA_EXCLUDES_FILE:-$SCRIPT_DIR/excludes.txt}"

export KOPIA_PASSWORD
export KOPIA_CACHE_DIRECTORY

require_cmd() {
  command -v "$1" >/dev/null 2>&1 || {
    echo "Missing required command: $1" >&2
    exit 1
  }
}

require_env() {
  local name="$1"
  if [[ -z "${!name:-}" ]]; then
    echo "Missing required environment variable: $name" >&2
    exit 1
  fi
}

require_real_env() {
  local name="$1"
  require_env "$name"
  case "${!name}" in
    change-me|change-me.*|*.change-me|*change-me*)
      echo "Environment variable $name still contains a placeholder value" >&2
      exit 1
      ;;
  esac
}

kopia_cmd() {
  kopia --config-file="$KOPIA_CONFIG_FILE" "$@"
}

log() {
  printf '[%s] %s\n' "$(date -u +'%Y-%m-%dT%H:%M:%SZ')" "$*"
}

ensure_runtime_dirs() {
  mkdir -p "$KOPIA_CACHE_DIRECTORY" "$KOPIA_LOG_DIR" "$BACKUP_STAGING_DIR"
}