"""order_candidates — the candidate sort used by attempt_download_with_candidates.

Default (priority mode) sorts confidence-first, then peer quality — today's
behaviour, locked here as a regression guard. quality_first=True (best-quality
mode) makes the user's profile quality rank dominate, with confidence as the
tiebreaker. Both keep correctly-matched candidates; ordering only changes which
is tried first.
"""

from core.downloads.candidates import order_candidates
from core.quality.model import AudioQuality, QualityTarget


class _Cand:
    def __init__(self, name, aq, confidence, quality_score=0,
                 upload_speed=0, queue_length=0, free_upload_slots=0, size=0):
        self.name = name
        self.audio_quality = aq
        self.confidence = confidence
        self.quality_score = quality_score
        self.upload_speed = upload_speed
        self.queue_length = queue_length
        self.free_upload_slots = free_upload_slots
        self.size = size


FLAC_HI = AudioQuality('flac', sample_rate=96000, bit_depth=24)
FLAC_CD = AudioQuality('flac', sample_rate=44100, bit_depth=16)

TARGETS = [
    QualityTarget(label='FLAC 24', format='flac', bit_depth=24, min_sample_rate=96000),
    QualityTarget(label='FLAC 16', format='flac', bit_depth=16),
]


def test_priority_mode_is_confidence_first():
    hi = _Cand('hi-flac', FLAC_HI, confidence=0.80)
    lo = _Cand('cd-flac', FLAC_CD, confidence=0.95)

    ordered = order_candidates([hi, lo], quality_first=False, targets=TARGETS)

    assert [c.name for c in ordered] == ['cd-flac', 'hi-flac']  # higher confidence wins


def test_quality_first_lets_better_quality_win_over_confidence():
    hi = _Cand('hi-flac', FLAC_HI, confidence=0.80)
    lo = _Cand('cd-flac', FLAC_CD, confidence=0.95)

    ordered = order_candidates([hi, lo], quality_first=True, targets=TARGETS)

    assert [c.name for c in ordered] == ['hi-flac', 'cd-flac']  # 24-bit beats higher-confidence 16-bit


def test_quality_first_uses_confidence_as_tiebreak_within_same_quality():
    a = _Cand('a', FLAC_HI, confidence=0.70)
    b = _Cand('b', FLAC_HI, confidence=0.90)

    ordered = order_candidates([a, b], quality_first=True, targets=TARGETS)

    assert [c.name for c in ordered] == ['b', 'a']  # same quality → confidence breaks tie


def test_quality_first_ranks_unmatched_quality_last():
    matched = _Cand('matched', FLAC_CD, confidence=0.50)
    off_list = _Cand('off', AudioQuality('mp3', bitrate=320), confidence=0.99)

    ordered = order_candidates([off_list, matched], quality_first=True, targets=TARGETS)

    assert [c.name for c in ordered] == ['matched', 'off']  # off-list sorts last despite high confidence