@type reps_spec() ::
  integer()
  | {integer(), integer()}
  | {integer(), integer(), integer()}
  | :amrap

@type t() :: %WplAi.AST.Exercise{
  exercise_ref: String.t(),
  meta: map(),
  movement_pattern: String.t() | nil,
  name: String.t() | nil,
  primary_muscles: [String.t()] | nil,
  reps: reps_spec(),
  rest: Duration.t() | nil,
  rir: integer() | nil,
  rir_max: integer() | nil,
  rir_min: integer() | nil,
  rpe: integer() | nil,
  rpe_max: integer() | nil,
  rpe_min: integer() | nil,
  secondary_muscles: [String.t()] | nil,
  sets: integer(),
  tempo: String.t() | nil,
  to_failure: true | nil,
  weight: Weight.t() | nil
}