"""Roll up per-session and per-QA evaluations into baseline-level summaries.

Recall & correctness: per-session average (not pooled cumulative).
Interference: pooled across sessions.
QA & evidence: pooled across questions.
"""

from __future__ import annotations

from collections.abc import Mapping, Sequence


def _safe_div(a: float, b: float) -> float:
    return a / b if b else 0.0


def aggregate_metrics(
    baseline_id: str,
    *,
    session_evaluations: Sequence[Mapping[str, object]] = (),
    qa_evaluations: Sequence[Mapping[str, object]] = (),
) -> dict[str, object]:
    """Aggregate all per-session and per-QA evaluations."""

    # --- Per-session recall (average) ---
    recall_scores: list[float] = []
    update_recall_scores: list[float] = []

    # --- Per-session correctness (average) ---
    correctness_scores: list[float] = []
    hallucination_scores: list[float] = []
    irrelevant_scores: list[float] = []

    # --- Update handling (pooled) ---
    upd_num_updated = 0
    upd_num_both = 0
    upd_num_outdated = 0
    upd_total_items = 0

    # --- Interference rejection (pooled) ---
    interf_num_rejected = 0
    interf_num_memorized = 0
    interf_total_items = 0

    # --- Per-session detail counters (for reference) ---
    total_gold_points = 0
    total_covered = 0
    total_memories = 0
    total_correct = 0
    total_hallucination = 0
    total_irrelevant = 0

    for s in session_evaluations:
        # Recall: per-session score
        r = s.get("recall")
        if r is not None:
            recall_scores.append(float(r))

        ur = s.get("update_recall")
        if ur is not None:
            update_recall_scores.append(float(ur))

        # Correctness: per-session score
        cr = s.get("correctness_rate")
        if cr is not None:
            correctness_scores.append(float(cr))

        nm = int(s.get("num_memories", 0))
        if nm > 0:
            hallucination_scores.append(
                float(s.get("num_hallucination", 0)) / nm
            )
            irrelevant_scores.append(
                float(s.get("num_irrelevant", 0)) / nm
            )

        # Detail counters
        c = s.get("covered_count")
        if c is not None:
            total_covered += int(c)
        total_gold_points += int(s.get("num_gold", 0))
        total_memories += nm
        total_correct += int(s.get("num_correct", 0))
        total_hallucination += int(s.get("num_hallucination", 0))
        total_irrelevant += int(s.get("num_irrelevant", 0))

        # Update handling (pooled)
        upd_num_updated += int(s.get("update_num_updated", 0))
        upd_num_both += int(s.get("update_num_both", 0))
        upd_num_outdated += int(s.get("update_num_outdated", 0))
        upd_total_items += int(s.get("update_total_items", 0))

        # Interference rejection (pooled)
        interf_num_rejected += int(s.get("interference_num_rejected", 0))
        interf_num_memorized += int(s.get("interference_num_memorized", 0))
        interf_total_items += int(s.get("interference_total_items", 0))

    # --- QA (pooled) ---
    qa_total = 0
    qa_valid = 0
    qa_correct = 0
    qa_hallucination = 0
    qa_omission = 0
    evidence_covered = 0
    evidence_total = 0

    for q in qa_evaluations:
        qa_total += 1
        label = q.get("answer_label")
        if label in ("Correct", "Hallucination", "Omission"):
            qa_valid += 1
            if label == "Correct":
                qa_correct += 1
            elif label == "Hallucination":
                qa_hallucination += 1
            elif label == "Omission":
                qa_omission += 1

        ec = q.get("evidence_covered_count")
        if ec is not None:
            evidence_covered += int(ec)
        evidence_total += int(q.get("num_evidence", 0))

    n_recall = len(recall_scores)
    n_update = len(update_recall_scores)
    n_correct = len(correctness_scores)
    n_hallu = len(hallucination_scores)
    n_irrel = len(irrelevant_scores)

    return {
        "baseline_id": baseline_id,
        "memory_recall": {
            "avg_recall": _safe_div(sum(recall_scores), n_recall),
            "avg_update_recall": _safe_div(sum(update_recall_scores), n_update),
            "num_sessions_with_recall": n_recall,
            "num_sessions_with_update": n_update,
            "total_covered": total_covered,
            "total_gold": total_gold_points,
        },
        "memory_correctness": {
            "avg_correctness": _safe_div(sum(correctness_scores), n_correct),
            "avg_hallucination": _safe_div(sum(hallucination_scores), n_hallu),
            "avg_irrelevant": _safe_div(sum(irrelevant_scores), n_irrel),
            "num_sessions": n_correct,
            "total_memories": total_memories,
            "total_correct": total_correct,
            "total_hallucination": total_hallucination,
            "total_irrelevant": total_irrelevant,
        },
        "update_handling": {
            "score": _safe_div(upd_num_updated * 1.0 + upd_num_both * 0.5, upd_total_items),
            "num_updated": upd_num_updated,
            "num_both": upd_num_both,
            "num_outdated": upd_num_outdated,
            "num_total": upd_total_items,
        },
        "interference_rejection": {
            "score": _safe_div(interf_num_rejected, interf_total_items),
            "num_rejected": interf_num_rejected,
            "num_memorized": interf_num_memorized,
            "num_total": interf_total_items,
        },
        "question_answering": {
            "correct_ratio": _safe_div(qa_correct, qa_valid),
            "hallucination_ratio": _safe_div(qa_hallucination, qa_valid),
            "omission_ratio": _safe_div(qa_omission, qa_valid),
            "num_total": qa_total,
            "num_valid": qa_valid,
        },
        "evidence_coverage": {
            "hit_rate": _safe_div(evidence_covered, evidence_total),
            "num_covered": evidence_covered,
            "num_total": evidence_total,
        },
    }