"""Realized gesture identities and their explicit development relationships."""
from __future__ import annotations

import dataclasses
import fractions

import generator.solo.harmonic
import generator.solo.scoring
import generator.solo.types

def reference(plan, gesture, realized):
  if not realized or gesture is None or gesture.relationship == 'statement':
    return plan.motif
  # Repetition returns to the introduced identity; extension/answer develops
  # the most recently heard related gesture, never an unrelated catalog winner.
  return realized[0] if gesture.relationship == 'repeat_with_harmonic_adaptation' else realized[-1]

def local_notes(notes, start, end):
  return tuple(dataclasses.replace(n, start=n.start - start, end=min(n.end, end) - start, position=None, continuation=False) for n in notes if start <= n.start < end)

def complete(gesture, reference, notes, harmony):
  actual = local_notes(notes, gesture.start, gesture.end)
  sounded = any(n.start < gesture.end and n.end > gesture.start for n in notes)
  active = any(s.scale and s.start < gesture.end and s.end > gesture.start for s in harmony.spans)
  if not active:
    return True, 0.0, None
  if gesture.relationship == 'close':
    return sounded, 0.0, None
  required = min(len(reference.notes), 2)
  if len(actual) < required:
    return False, 1.0, None
  fidelity = generator.solo.scoring.motif_fidelity(actual, reference, gesture.treatment)
  if gesture.treatment == 'rhythmic_reference':
    expected = tuple((n.start, min(n.end, gesture.end - gesture.start)) for n in reference.notes if n.start < gesture.end - gesture.start)
    if tuple((n.start, n.end) for n in actual) != expected:
      return False, 1.0, None
  elif gesture.relationship != 'statement' and fidelity >= 0.75:
    return False, fidelity, None
  degrees = []
  for n in actual:
    span = harmony.at(gesture.start + n.start)
    degrees.append(dict(span.roles.degrees).get(n.pitch.number() % 12, ()) if span else ())
  result = generator.solo.types.RealizedMotif(gesture.id, reference.id, actual, gesture.end - gesture.start, gesture.relationship, gesture.treatment, tuple(degrees), gesture.start)
  return True, fidelity, result

def interval_steps(reference, harmony, source_start=None):
  result = []
  source_start = getattr(reference, 'source_start', source_start or fractions.Fraction())
  for first, second in zip(reference.notes, reference.notes[1:]):
    span = harmony.at((source_start or fractions.Fraction()) + first.start)
    try:
      step = generator.solo.types.scale_index(span.scale, second.pitch.number()) - generator.solo.types.scale_index(span.scale, first.pitch.number()) if span and span.scale else None
    except ValueError:
      step = None
    result.append((step, second.pitch.number() - first.pitch.number()))
  return tuple(result)