/// Represents keys in the environment that can be used to locate a user's
/// configuration file.
@_spi(Internal)
public enum EnvironmentKey {
  static let xdgConfigHome = "XDG_CONFIG_HOME"
  static let hpaConfigHome = "HPA_CONFIG_HOME"
  static let hpaConfigFile = "HPA_CONFIG_FILE"
}

/// Represents keys that are used internally for directory names, file names, etc.
@_spi(Internal)
public enum HPAKey {
  public static let configDirName = "hpa"
  public static let resourceFileName = "hpa"
  public static let resourceFileExtension = "toml"
  public static let defaultFileName = "config.toml"
  public static let defaultFileNameWithoutExtension = "config.toml"
}

extension [String: String] {
  var xdgConfigHome: String {
    self[EnvironmentKey.xdgConfigHome] ?? "~/.config"
  }

  var hpaConfigHome: String? {
    self[EnvironmentKey.hpaConfigHome]
  }

  var hpaConfigFile: String? {
    self[EnvironmentKey.hpaConfigFile]
  }
}