"""GPQA Diamond.

Official source Idavidrein/gpqa is gated on HF (needs auth); we load the
nmayorga7 CSV export which keeps the official column layout (Question /
Correct Answer / Incorrect Answer 1-3).

Note: choices are stored with the correct answer first (target 'A').
Option shuffling is an eval-time concern (the evaluator should shuffle
choices and remap the target, like Dataset.shuffle_choices would).
"""

from ..sample import Sample
from ..registry import register_dataset
from ..spec import DatasetSpec


@register_dataset(
    DatasetSpec(
        name='gpqa_diamond',
        source='nmayorga7/gpqa_diamond',  # HF CSV export of the gated official
        split='train',
        gen_config={'temperature': 1.0, 'max_tokens': 8192},
        task_type='mcq',
        tags=['knowledge', 'science'],
        description='GPQA diamond split, graduate-level science MCQ (official content).',
        params={'hub': 'hf_raw'},
    )
)
def gpqa_diamond():
    def to_sample(record: dict) -> Sample:
        # position-bias protection, ported from the es adapter: deterministic
        # per-question shuffle (seed = sha256(question)) keeps reruns identical
        import hashlib
        import random as _rnd

        choices = [
            str(record['Incorrect Answer 1'] or '').strip(),
            str(record['Incorrect Answer 2'] or '').strip(),
            str(record['Incorrect Answer 3'] or '').strip(),
            str(record['Correct Answer'] or '').strip(),
        ]
        seed = int.from_bytes(
            hashlib.sha256(str(record['Question']).strip().encode('utf-8')).digest()[:8], 'big')
        _rnd.Random(seed).shuffle(choices)
        target = 'ABCD'[choices.index(str(record['Correct Answer'] or '').strip())]
        return Sample(
            input=record['Question'],
            choices=choices,
            target=target,
            metadata={'subdomain': record.get('Subdomain')},
        )

    return to_sample