"""Materialize fail-closed data-quality evidence for a frozen split."""

from __future__ import annotations

from pathlib import Path
from typing import Any

from .artifacts import sha256_file, write_json_immutable
from .config import LoadedConfig
from .data import ALLOWED_MODEL_INPUTS, BGCEmbeddingDataset
from .splits import load_split, split_summary


def validate_frozen_dataset(
    config: LoadedConfig,
    split_path: str | Path,
    output_dir: str | Path,
) -> dict[str, Any]:
    assignments = load_split(split_path)
    dataset = BGCEmbeddingDataset(
        config.resolve_path("data", "embeddings_h5"),
        config.resolve_path("data", "atlas_csv"),
        assignments,
        int(config.values["model"]["esm_dimension"]),
    )
    output = Path(output_dir)
    output.mkdir(parents=True, exist_ok=True)
    exclusion_path = output / "missing_embedding_rows.csv"
    if exclusion_path.exists():
        raise FileExistsError(f"Refusing to overwrite quality artifact: {exclusion_path}")
    dataset.missing_gene_rows.to_csv(exclusion_path, index=False)
    usable_gene_rows = sum(len(dataset.bgc_to_genes[bgc_id]) for bgc_id in dataset.bgc_ids)
    missing_gene_rows = len(dataset.missing_gene_rows)
    report: dict[str, Any] = {
        "schema_version": 1,
        "split_file_sha256": sha256_file(split_path),
        "atlas_file_sha256": sha256_file(config.resolve_path("data", "atlas_csv")),
        "embeddings_file_sha256": sha256_file(config.resolve_path("data", "embeddings_h5")),
        "split": split_summary(assignments),
        "usable_bgcs": len(dataset),
        "usable_gene_rows": usable_gene_rows,
        "missing_embedding_rows": missing_gene_rows,
        "embedding_coverage": usable_gene_rows / (usable_gene_rows + missing_gene_rows),
        "position_source": "ordered community_atlas.protein_ids",
        "model_input_whitelist": sorted(ALLOWED_MODEL_INPUTS),
        "zero_gene_fallback": False,
    }
    write_json_immutable(output / "data_quality.json", report)
    return report