"""Sounding-register references and hard solo instrument domains."""
from __future__ import annotations

import dataclasses
import fractions
import functools

import generator.fretboard

@dataclasses.dataclass(frozen=True)
class Instrument:
  part: str = ''
  strings: tuple[int, ...] = (1, 2, 3, 4, 5, 6)
  reference: int | None = None
  melody_range: tuple[int, int] | None = None
  @property
  def register(self):
    tuning = [p for s, p in generator.fretboard.STANDARD_TUNING if s in self.strings]
    return min(tuning) + 1, max(tuning) + 12
  @functools.lru_cache(maxsize=4096)
  def permits(self, number):
    return any(p.string_number in self.strings for p in generator.fretboard.single_positions_for_pitch(fractions.Fraction(number)))

UNRESTRICTED = Instrument()

def for_part(part, analysis=None):
  if part not in ('acoustic', 'electric'):
    raise ValueError('unknown solo instrument: ' + part)
  strings = (1, 2, 3, 4, 5, 6)
  if analysis is None or not analysis.melody:
    return Instrument(part, strings)
  return Instrument(part, strings)