#!/usr/bin/env bash

if [[ -n "${ATLAS_FILES_SH_LOADED:-}" ]]; then
  return 0
fi
ATLAS_FILES_SH_LOADED=1

atlas_ensure_directory() {
  local path="$1"
  local mode="${2:-0750}"
  local owner="${3:-}"

  if [[ -d "$path" ]]; then
    atlas_log_verbose "Directory already exists: ${path}"
    return 0
  fi

  if [[ "${ATLAS_DRY_RUN:-0}" == "1" ]]; then
    atlas_log_info "Dry-run mode: would create directory ${path} with mode ${mode}"
    return 0
  fi

  if [[ -n "$owner" ]]; then
    atlas_sudo_run install -d -m "$mode" -o "${owner%%:*}" -g "${owner##*:}" "$path"
  else
    atlas_sudo_run install -d -m "$mode" "$path"
  fi
}

atlas_backup_file() {
  local path="$1"
  local backup_dir="${2:-$(dirname "$path")}"
  local timestamp
  timestamp="$(date -u '+%Y%m%dT%H%M%SZ')"

  if [[ ! -e "$path" ]]; then
    return 0
  fi

  local backup_path="${backup_dir}/$(basename "$path").${timestamp}.bak"
  if [[ "${ATLAS_DRY_RUN:-0}" == "1" ]]; then
    atlas_log_info "Dry-run mode: would back up ${path} to ${backup_path}"
    printf '%s\n' "$backup_path"
    return 0
  fi

  if [[ ! -d "$backup_dir" ]]; then
    if [[ -w "$(dirname "$backup_dir")" ]]; then
      install -d -m 0750 "$backup_dir"
    else
      atlas_sudo_run install -d -m 0750 "$backup_dir"
    fi
  fi

  if [[ -w "$backup_dir" && -r "$path" ]]; then
    cp -a "$path" "$backup_path"
  else
    atlas_sudo_run cp -a "$path" "$backup_path"
  fi
  atlas_log_info "Backed up ${path} to ${backup_path}"
  printf '%s\n' "$backup_path"
}

atlas_replace_file_if_changed() {
  local source="$1"
  local destination="$2"
  local mode="${3:-0644}"
  local owner="${4:-}"
  local backup_dir="${5:-$(dirname "$destination")}"

  if [[ ! -f "$source" ]]; then
    atlas_log_error "Replacement source is not a file: ${source}"
    return "${ATLAS_EXIT_USAGE:-2}"
  fi

  if [[ -f "$destination" ]] && cmp -s "$source" "$destination"; then
    atlas_log_ok "No change required for ${destination}"
    return 0
  fi

  if [[ "${ATLAS_DRY_RUN:-0}" == "1" ]]; then
    if [[ -e "$destination" ]]; then
      atlas_log_info "Dry-run mode: would back up and replace ${destination}"
    else
      atlas_log_info "Dry-run mode: would create ${destination}"
    fi
    return 0
  fi

  if [[ -e "$destination" ]]; then
    atlas_backup_file "$destination" "$backup_dir" >/dev/null
  fi

  local destination_dir tmp_path
  destination_dir="$(dirname "$destination")"
  if [[ -w "$destination_dir" ]]; then
    tmp_path="$(mktemp "${destination}.tmp.XXXXXX")"
  else
    tmp_path="$(mktemp)"
  fi
  cp "$source" "$tmp_path"
  chmod "$mode" "$tmp_path"
  if [[ -n "$owner" ]]; then
    if [[ "${EUID}" -eq 0 ]]; then
      chown "$owner" "$tmp_path"
    elif [[ -w "$destination_dir" ]]; then
      chown "$owner" "$tmp_path"
    else
      sudo -n chown "$owner" "$tmp_path"
    fi
  fi

  if [[ -w "$destination_dir" ]]; then
    mv "$tmp_path" "$destination"
  else
    atlas_sudo_run install -m "$mode" "$tmp_path" "$destination"
    rm -f "$tmp_path"
  fi
  atlas_log_ok "Updated ${destination}"
}