"""Postgres persistence for the G7 consent-bound multimodal ledger."""

from __future__ import annotations

import hashlib
import json
from collections.abc import Mapping, Sequence
from datetime import UTC, datetime, timedelta
from typing import Any
from uuid import NAMESPACE_URL, UUID, uuid4, uuid5

import asyncpg

from .. import db
from ..config import settings
from ..contracts.multimodal_alliance import (
    AlignedVoiceTimeline,
    FusionCalibration,
    ModalityAxisMeasurement,
)
from ..deps import Principal, Role
from .multimodal_alliance import build_calibrated_axis_read_model


class MultimodalAllianceError(RuntimeError):
    pass


class MultimodalAllianceNotFoundError(MultimodalAllianceError):
    pass


class MultimodalAllianceConflictError(MultimodalAllianceError):
    pass


class MultimodalAllianceStateError(MultimodalAllianceError):
    pass


class MultimodalConsentRequiredError(MultimodalAllianceStateError):
    pass


class MultimodalConsentWithdrawnError(MultimodalAllianceStateError):
    pass


def _value(row: Any, key: str, default: Any = None) -> Any:
    if row is None:
        return default
    if isinstance(row, Mapping):
        return row.get(key, default)
    try:
        return row[key]
    except (KeyError, TypeError):
        return getattr(row, key, default)


def _canonical_hash(payload: object) -> str:
    encoded = json.dumps(
        payload,
        ensure_ascii=False,
        sort_keys=True,
        separators=(",", ":"),
        default=str,
    ).encode("utf-8")
    return hashlib.sha256(encoded).hexdigest()


async def _visible_session(conn: asyncpg.Connection, session_id: UUID) -> Any:
    row = await conn.fetchrow(
        "SELECT id, learner_id FROM app.sessions WHERE id = $1",
        session_id,
    )
    if row is None:
        raise MultimodalAllianceNotFoundError("session not found or not visible")
    return row


async def _latest_consent(conn: asyncpg.Connection, session_id: UUID) -> Any:
    return await conn.fetchrow(
        """
        SELECT consent_snapshot_id, learner_id, sequence_no, consent_status,
               retain_audio, retain_derived_features, transcript_retained,
               retention_days, policy_version, reason_code, created_at
        FROM app.multimodal_consent_snapshot
        WHERE session_id = $1
        ORDER BY sequence_no DESC
        LIMIT 1
        """,
        session_id,
    )


async def _lock_consent_processing(
    conn: asyncpg.Connection, session_id: UUID
) -> None:
    """Serialize consent mutation with all consent-bound persistence.

    The database triggers still enforce the latest snapshot at INSERT time.
    This shared transaction lock additionally gives concurrent withdrawal and
    evaluator persistence one unambiguous order, so a writer that starts after
    withdrawal commits cannot persist derived voice data from a stale grant.
    """

    await conn.execute(
        "SELECT pg_advisory_xact_lock(hashtextextended($1::text, 0))",
        f"multimodal-consent:{session_id}",
    )


async def _existing_request(
    conn: asyncpg.Connection,
    *,
    submission_id: UUID,
    request_kind: str,
    content_hash: str,
    session_id: UUID,
    learner_id: UUID,
) -> UUID | None:
    row = await conn.fetchrow(
        """
        SELECT request_kind, content_hash, session_id, learner_id, result_id
        FROM app.multimodal_ingestion_request
        WHERE submission_id = $1
        """,
        submission_id,
    )
    if row is None:
        return None
    if (
        _value(row, "request_kind") != request_kind
        or _value(row, "content_hash") != content_hash
        or UUID(str(_value(row, "session_id"))) != session_id
        or UUID(str(_value(row, "learner_id"))) != learner_id
    ):
        raise MultimodalAllianceConflictError(
            "submission_id was already used with different multimodal content"
        )
    return UUID(str(_value(row, "result_id")))


async def _insert_request(
    conn: asyncpg.Connection,
    *,
    submission_id: UUID,
    content_hash: str,
    request_kind: str,
    session_id: UUID,
    learner_id: UUID,
    result_id: UUID,
    created_by_role: str,
) -> None:
    await conn.execute(
        """
        INSERT INTO app.multimodal_ingestion_request (
          submission_id, content_hash, request_kind, session_id, learner_id,
          result_id, created_by_role
        ) VALUES ($1,$2,$3,$4,$5,$6,$7)
        """,
        submission_id,
        content_hash,
        request_kind,
        session_id,
        learner_id,
        result_id,
        created_by_role,
    )


def _withdrawal_ids(submission_id: UUID) -> tuple[UUID, UUID]:
    deletion_submission_id = uuid5(
        NAMESPACE_URL, f"vignette:g7:withdrawal-submission:{submission_id}"
    )
    deletion_request_id = uuid5(
        NAMESPACE_URL, f"vignette:g7:withdrawal-request:{submission_id}"
    )
    return deletion_submission_id, deletion_request_id


async def _insert_deletion_request(
    conn: asyncpg.Connection,
    *,
    submission_id: UUID,
    deletion_request_id: UUID,
    session_id: UUID,
    learner_id: UUID,
    scopes: Sequence[str],
    request_reason: str,
    requested_by_uid: UUID,
    created_by_role: str,
) -> tuple[UUID, bool]:
    unique_scopes = tuple(sorted(set(scopes)))
    if not unique_scopes or not set(unique_scopes) <= {
        "audio",
        "derived_features",
        "transcript",
    }:
        raise MultimodalAllianceStateError("unsupported deletion scope")
    payload = {
        "session_id": str(session_id),
        "learner_id": str(learner_id),
        "scopes": unique_scopes,
        "request_reason": request_reason,
        "requested_by_uid": str(requested_by_uid),
    }
    content_hash = _canonical_hash(payload)
    existing = await _existing_request(
        conn,
        submission_id=submission_id,
        request_kind="deletion_request",
        content_hash=content_hash,
        session_id=session_id,
        learner_id=learner_id,
    )
    if existing is not None:
        return existing, True
    await _insert_request(
        conn,
        submission_id=submission_id,
        content_hash=content_hash,
        request_kind="deletion_request",
        session_id=session_id,
        learner_id=learner_id,
        result_id=deletion_request_id,
        created_by_role=created_by_role,
    )
    await conn.execute(
        """
        INSERT INTO app.multimodal_deletion_request (
          deletion_request_id, submission_id, session_id, learner_id,
          scopes, request_reason, requested_by_uid
        ) VALUES ($1,$2,$3,$4,$5::text[],$6,$7)
        """,
        deletion_request_id,
        submission_id,
        session_id,
        learner_id,
        list(unique_scopes),
        request_reason,
        requested_by_uid,
    )
    return deletion_request_id, False


async def append_consent_snapshot(
    *,
    principal: Principal,
    session_id: UUID,
    submission_id: UUID,
    consent_status: str,
    retain_audio: bool,
    retain_derived_features: bool,
    transcript_retained: bool,
    retention_days: int | None,
    policy_version: str,
    reason_code: str | None,
) -> dict[str, Any]:
    if principal.role != Role.LEARNER:
        raise MultimodalAllianceStateError(
            "only the learner may change multimodal consent"
        )
    if consent_status not in {"granted", "withdrawn", "not_granted"}:
        raise MultimodalAllianceStateError("unsupported consent status")
    if not transcript_retained:
        raise MultimodalAllianceStateError(
            "G7 deletes audio and derived features only; masked transcript remains retained"
        )
    if consent_status == "granted":
        if not retain_derived_features or retention_days is None:
            raise MultimodalAllianceStateError(
                "granted multimodal consent requires derived retention and expiry"
            )
    elif retain_audio or retain_derived_features or retention_days is not None:
        raise MultimodalAllianceStateError(
            "ungranted consent must not retain audio or derived features"
        )
    learner_id = UUID(principal.user_id)
    payload = {
        "session_id": str(session_id),
        "consent_status": consent_status,
        "retain_audio": retain_audio,
        "retain_derived_features": retain_derived_features,
        "transcript_retained": transcript_retained,
        "retention_days": retention_days,
        "policy_version": policy_version.strip(),
        "reason_code": reason_code.strip() if reason_code else None,
    }
    content_hash = _canonical_hash(payload)
    consent_snapshot_id = uuid4()
    deletion_request_id: UUID | None = None
    async with db.acquire(
        role=principal.role.value,
        user_id=principal.user_id,
        cohort_ids=principal.cohort_ids,
    ) as conn:
        await _lock_consent_processing(conn, session_id)
        session = await _visible_session(conn, session_id)
        if UUID(str(_value(session, "learner_id"))) != learner_id:
            raise MultimodalAllianceNotFoundError("session not found or not visible")
        existing = await _existing_request(
            conn,
            submission_id=submission_id,
            request_kind="consent",
            content_hash=content_hash,
            session_id=session_id,
            learner_id=learner_id,
        )
        if existing is not None:
            deletion = await conn.fetchrow(
                """
                SELECT deletion_request_id FROM app.multimodal_deletion_request
                WHERE session_id = $1 AND request_reason = 'consent_withdrawal'
                ORDER BY requested_at DESC LIMIT 1
                """,
                session_id,
            )
            return {
                "submission_id": submission_id,
                "consent_snapshot_id": existing,
                "consent_status": consent_status,
                "deletion_request_id": (
                    UUID(str(_value(deletion, "deletion_request_id")))
                    if deletion is not None
                    else None
                ),
                "idempotent_replay": True,
            }
        latest = await _latest_consent(conn, session_id)
        if latest is not None and _value(latest, "consent_status") == "withdrawn":
            raise MultimodalAllianceConflictError(
                "withdrawn multimodal consent is terminal for this session"
            )
        sequence_no = int(_value(latest, "sequence_no", 0)) + 1
        await _insert_request(
            conn,
            submission_id=submission_id,
            content_hash=content_hash,
            request_kind="consent",
            session_id=session_id,
            learner_id=learner_id,
            result_id=consent_snapshot_id,
            created_by_role="learner",
        )
        try:
            await conn.execute(
                """
                INSERT INTO app.multimodal_consent_snapshot (
                  consent_snapshot_id, submission_id, session_id, learner_id,
                  sequence_no, consent_status, retain_audio,
                  retain_derived_features, transcript_retained, retention_days,
                  policy_version, reason_code, created_by_uid
                ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12,$13)
                """,
                consent_snapshot_id,
                submission_id,
                session_id,
                learner_id,
                sequence_no,
                consent_status,
                retain_audio,
                retain_derived_features,
                transcript_retained,
                retention_days,
                payload["policy_version"],
                payload["reason_code"],
                learner_id,
            )
            if consent_status == "withdrawn":
                deletion_submission_id, deletion_request_id = _withdrawal_ids(
                    submission_id
                )
                await _insert_deletion_request(
                    conn,
                    submission_id=deletion_submission_id,
                    deletion_request_id=deletion_request_id,
                    session_id=session_id,
                    learner_id=learner_id,
                    scopes=("audio", "derived_features"),
                    request_reason="consent_withdrawal",
                    requested_by_uid=learner_id,
                    created_by_role="learner",
                )
        except (asyncpg.CheckViolationError, asyncpg.ForeignKeyViolationError) as exc:
            raise MultimodalAllianceStateError(
                "multimodal consent violated ownership or retention invariants"
            ) from exc
        except asyncpg.UniqueViolationError as exc:
            raise MultimodalAllianceConflictError(
                "multimodal consent submission already exists"
            ) from exc
    return {
        "submission_id": submission_id,
        "consent_snapshot_id": consent_snapshot_id,
        "consent_status": consent_status,
        "deletion_request_id": deletion_request_id,
        "idempotent_replay": False,
    }


async def assert_voice_processing_allowed(
    *, principal: Principal, session_id: str
) -> dict[str, Any] | None:
    """Fail closed for enrolled sessions after refusal/withdrawal.

    A database without the G7 migration is treated as a legacy, non-enrolled
    deployment so the pre-existing voice cascade remains available. Any other
    database error propagates before STT is invoked.
    """

    try:
        session_uuid = UUID(session_id)
    except ValueError:
        return None
    try:
        async with db.acquire(
            role=principal.role.value,
            user_id=principal.user_id,
            cohort_ids=principal.cohort_ids,
        ) as conn:
            await _visible_session(conn, session_uuid)
            consent = await _latest_consent(conn, session_uuid)
    except (
        RuntimeError,
        asyncpg.UndefinedTableError,
        MultimodalAllianceNotFoundError,
    ) as exc:
        if settings.environment == "dev":
            return None
        raise MultimodalAllianceStateError(
            "multimodal consent state is unavailable; voice processing is blocked"
        ) from exc
    if consent is None:
        return None
    status = str(_value(consent, "consent_status"))
    if status == "withdrawn":
        raise MultimodalConsentWithdrawnError(
            "multimodal consent was withdrawn; new voice processing is blocked"
        )
    if status != "granted":
        raise MultimodalConsentRequiredError(
            "multimodal voice processing consent was not granted"
        )
    return {
        "consent_snapshot_id": UUID(str(_value(consent, "consent_snapshot_id"))),
        "retain_audio": bool(_value(consent, "retain_audio")),
        "retain_derived_features": bool(_value(consent, "retain_derived_features")),
        "retention_days": int(_value(consent, "retention_days")),
    }


async def append_runtime_timeline(
    *,
    session_id: str,
    submission_id: UUID,
    timeline: AlignedVoiceTimeline,
    audio_asset: Mapping[str, Any] | None,
) -> dict[str, Any] | None:
    """Append a consent-bound runtime STT timeline using evaluator RLS.

    Legacy development sessions may run without the G7 migration. Staging and
    production never reinterpret a missing schema/session as permission.
    """

    try:
        session_uuid = UUID(session_id)
    except ValueError as exc:
        if settings.environment == "dev":
            return None
        raise MultimodalAllianceStateError(
            "multimodal timeline session identity is invalid"
        ) from exc

    try:
        async with db.acquire(ai_view="evaluator", ai_context=True) as conn:
            await _visible_session(conn, session_uuid)
            consent = await _latest_consent(conn, session_uuid)
            if consent is None:
                return None
            consent_status = str(_value(consent, "consent_status"))
            if consent_status == "withdrawn":
                raise MultimodalConsentWithdrawnError(
                    "multimodal consent was withdrawn; timeline persistence is blocked"
                )
            if consent_status != "granted":
                raise MultimodalConsentRequiredError(
                    "multimodal voice processing consent was not granted"
                )
            if not bool(_value(consent, "retain_derived_features")):
                return {
                    "submission_id": submission_id,
                    "retention": "derived_features_disabled",
                }
            retained_audio_asset = (
                audio_asset if bool(_value(consent, "retain_audio")) else None
            )
            if retained_audio_asset is None and bool(_value(consent, "retain_audio")):
                raise MultimodalAllianceStateError(
                    "consented audio retention requires runtime audio metadata"
                )
            return await append_timeline(
                conn=conn,
                session_id=session_uuid,
                submission_id=submission_id,
                timeline=timeline,
                audio_asset=retained_audio_asset,
            )
    except MultimodalAllianceNotFoundError as exc:
        if settings.environment == "dev":
            return None
        raise MultimodalAllianceStateError(
            "multimodal timeline session is unavailable"
        ) from exc
    except MultimodalAllianceError:
        raise
    except (RuntimeError, asyncpg.UndefinedTableError) as exc:
        if settings.environment == "dev":
            return None
        raise MultimodalAllianceStateError(
            "multimodal timeline persistence is unavailable"
        ) from exc


async def append_timeline(
    *,
    conn: asyncpg.Connection,
    session_id: UUID,
    submission_id: UUID,
    timeline: AlignedVoiceTimeline,
    audio_asset: Mapping[str, Any] | None,
) -> dict[str, Any]:
    await _lock_consent_processing(conn, session_id)
    await conn.execute(
        "SELECT pg_advisory_xact_lock(hashtextextended($1::text, 0))",
        f"multimodal-timeline:{session_id}",
    )
    session = await _visible_session(conn, session_id)
    learner_id = UUID(str(_value(session, "learner_id")))
    consent = await _latest_consent(conn, session_id)
    if consent is None or _value(consent, "consent_status") != "granted":
        raise MultimodalConsentRequiredError(
            "latest granted consent is required before voice processing"
        )
    if not bool(_value(consent, "retain_derived_features")):
        raise MultimodalConsentRequiredError(
            "derived feature processing was not granted"
        )
    retain_audio = bool(_value(consent, "retain_audio"))
    if retain_audio != (audio_asset is not None):
        raise MultimodalAllianceStateError(
            "audio metadata must exactly follow the consent retention snapshot"
        )
    payload = {
        "session_id": str(session_id),
        "timeline": timeline.model_dump(mode="json"),
        "audio_asset": dict(audio_asset) if audio_asset is not None else None,
        "consent_snapshot_id": str(_value(consent, "consent_snapshot_id")),
    }
    content_hash = _canonical_hash(payload)
    existing = await _existing_request(
        conn,
        submission_id=submission_id,
        request_kind="timeline",
        content_hash=content_hash,
        session_id=session_id,
        learner_id=learner_id,
    )
    if existing is not None:
        return {
            "submission_id": submission_id,
            "timeline_id": existing,
            "idempotent_replay": True,
        }
    timeline_id = uuid4()
    audio_asset_id = uuid4() if audio_asset is not None else None
    await _insert_request(
        conn,
        submission_id=submission_id,
        content_hash=content_hash,
        request_kind="timeline",
        session_id=session_id,
        learner_id=learner_id,
        result_id=timeline_id,
        created_by_role="evaluator",
    )
    try:
        if audio_asset is not None:
            retention_days = int(_value(consent, "retention_days"))
            retained_until = datetime.now(UTC) + timedelta(days=retention_days)
            await conn.execute(
                """
                INSERT INTO app.multimodal_audio_asset (
                  audio_asset_id, timeline_submission_id, session_id, learner_id,
                  consent_snapshot_id, audio_ref, audio_sha256, media_type,
                  byte_size, duration_ms, retained_until
                ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11)
                """,
                audio_asset_id,
                submission_id,
                session_id,
                learner_id,
                _value(consent, "consent_snapshot_id"),
                str(audio_asset["audio_ref"]),
                str(audio_asset["audio_sha256"]),
                str(audio_asset["media_type"]),
                int(audio_asset["byte_size"]),
                timeline.audio_duration_ms,
                retained_until,
            )
        await conn.execute(
            """
            INSERT INTO app.multimodal_audio_timeline (
              timeline_id, submission_id, session_id, learner_id,
              consent_snapshot_id, audio_asset_id, audio_duration_ms,
              word_count, event_count
            ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9)
            """,
            timeline_id,
            submission_id,
            session_id,
            learner_id,
            _value(consent, "consent_snapshot_id"),
            audio_asset_id,
            timeline.audio_duration_ms,
            len(timeline.words),
            len(timeline.events),
        )
        for word in timeline.words:
            await conn.execute(
                """
                INSERT INTO app.multimodal_word_timestamp (
                  word_timestamp_id, timeline_id, session_id, learner_id,
                  word_index, start_ms, end_ms, speaker, token_hash
                ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9)
                """,
                uuid4(),
                timeline_id,
                session_id,
                learner_id,
                word.word_index,
                word.start_ms,
                word.end_ms,
                word.speaker,
                word.token_hash,
            )
        for event in timeline.events:
            await conn.execute(
                """
                INSERT INTO app.multimodal_voice_event (
                  voice_event_record_id, timeline_id, session_id, learner_id,
                  event_id, event_type, start_ms, end_ms, actor,
                  observed_feature, uncertainty, source
                ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12)
                """,
                uuid4(),
                timeline_id,
                session_id,
                learner_id,
                event.event_id,
                event.event_type,
                event.start_ms,
                event.end_ms,
                event.actor,
                event.observed_feature,
                event.uncertainty,
                event.source,
            )
        await conn.execute(
            "SET CONSTRAINTS app.trg_multimodal_timeline_counts, "
            "app.trg_multimodal_word_counts, app.trg_multimodal_event_counts "
            "IMMEDIATE"
        )
    except (asyncpg.CheckViolationError, asyncpg.ForeignKeyViolationError) as exc:
        raise MultimodalAllianceStateError(
            "multimodal timeline violated consent, clock, or observation invariants"
        ) from exc
    except asyncpg.UniqueViolationError as exc:
        raise MultimodalAllianceConflictError(
            "multimodal timeline submission already exists"
        ) from exc
    return {
        "submission_id": submission_id,
        "timeline_id": timeline_id,
        "audio_asset_id": audio_asset_id,
        "idempotent_replay": False,
    }


def _measurement_values(
    measurement: ModalityAxisMeasurement,
    provenance: Mapping[str, str],
) -> tuple[Any, ...]:
    return (
        measurement.measurement_id,
        measurement.axis,
        measurement.modality,
        measurement.status,
        measurement.value,
        measurement.confidence,
        measurement.uncertainty,
        list(measurement.evidence_refs),
        measurement.model_run_id,
        provenance["instrument_id"],
        provenance["instrument_version"],
        provenance["model_name"],
        provenance["prompt_version"],
        f"model_inferred_{measurement.modality}",
        measurement.error_code,
    )


async def append_measurement_fusion(
    *,
    conn: asyncpg.Connection,
    session_id: UUID,
    submission_id: UUID,
    text: ModalityAxisMeasurement,
    voice: ModalityAxisMeasurement,
    calibration: FusionCalibration,
    text_provenance: Mapping[str, str],
    voice_provenance: Mapping[str, str],
) -> dict[str, Any]:
    if text.modality != "text" or voice.modality != "voice":
        raise MultimodalAllianceStateError(
            "text and voice measurements must keep independent modality provenance"
        )
    if text.status != "ready":
        raise MultimodalAllianceStateError(
            "a ready text measurement is required as the fail-safe baseline"
        )
    await _lock_consent_processing(conn, session_id)
    session = await _visible_session(conn, session_id)
    learner_id = UUID(str(_value(session, "learner_id")))
    consent = await _latest_consent(conn, session_id)
    consent_status = _value(consent, "consent_status") if consent is not None else None
    if voice.status == "ready" and consent_status != "granted":
        raise MultimodalConsentRequiredError(
            "ready voice measurement requires current granted consent"
        )
    if consent_status == "withdrawn" and voice.status != "missing":
        raise MultimodalConsentWithdrawnError(
            "withdrawal permits only an explicit missing voice measurement"
        )
    result = build_calibrated_axis_read_model(
        text=text,
        voice=voice,
        calibration=calibration,
    )
    payload = {
        "session_id": str(session_id),
        "text": text.model_dump(mode="json"),
        "voice": voice.model_dump(mode="json"),
        "calibration": calibration.model_dump(mode="json"),
        "text_provenance": dict(text_provenance),
        "voice_provenance": dict(voice_provenance),
    }
    content_hash = _canonical_hash(payload)
    await conn.execute(
        "SELECT pg_advisory_xact_lock(hashtextextended($1::text, 0))",
        f"multimodal-measurement:{submission_id}",
    )
    existing = await _existing_request(
        conn,
        submission_id=submission_id,
        request_kind="measurement_fusion",
        content_hash=content_hash,
        session_id=session_id,
        learner_id=learner_id,
    )
    if existing is not None:
        return {
            "submission_id": submission_id,
            "fusion_record_id": existing,
            "result": result.model_dump(mode="json"),
            "idempotent_replay": True,
        }
    fusion_record_id = uuid4()
    await _insert_request(
        conn,
        submission_id=submission_id,
        content_hash=content_hash,
        request_kind="measurement_fusion",
        session_id=session_id,
        learner_id=learner_id,
        result_id=fusion_record_id,
        created_by_role="evaluator",
    )
    try:
        for measurement, provenance in (
            (text, text_provenance),
            (voice, voice_provenance),
        ):
            await conn.execute(
                """
                INSERT INTO app.multimodal_axis_measurement (
                  measurement_record_id, submission_id, session_id, learner_id,
                  measurement_id, axis, modality, status, value, confidence,
                  uncertainty, evidence_refs, model_run_id, instrument_id,
                  instrument_version, model_name, prompt_version, source_kind,
                  error_code
                ) VALUES (
                  $1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12::text[],$13,$14,$15,
                  $16,$17,$18,$19
                )
                """,
                uuid4(),
                submission_id,
                session_id,
                learner_id,
                *_measurement_values(measurement, provenance),
            )
        await conn.execute(
            """
            INSERT INTO app.multimodal_fusion_decision (
              fusion_record_id, submission_id, session_id, learner_id, axis,
              status, value, uncertainty, modalities_used, measurement_ids,
              fusion_applied, calibration_id, benchmark_version, text_weight,
              voice_weight, text_only_accuracy, fused_accuracy,
              minimum_incremental_gain, incremental_gain, counterevidence
            ) VALUES (
              $1,$2,$3,$4,$5,$6,$7,$8,$9::text[],$10::text[],$11,$12,$13,$14,
              $15,$16,$17,$18,$19,$20::text[]
            )
            """,
            fusion_record_id,
            submission_id,
            session_id,
            learner_id,
            result.axis,
            result.status,
            result.value,
            result.uncertainty,
            list(result.modalities_used),
            list(result.measurement_ids),
            result.fusion_applied,
            result.fusion_calibration_id,
            calibration.benchmark_version,
            calibration.text_weight,
            calibration.voice_weight,
            calibration.text_only_accuracy,
            calibration.fused_accuracy,
            calibration.minimum_incremental_gain,
            calibration.incremental_gain,
            list(result.counterevidence),
        )
    except (asyncpg.CheckViolationError, asyncpg.ForeignKeyViolationError) as exc:
        raise MultimodalAllianceStateError(
            "multimodal measurement violated provenance or fusion invariants"
        ) from exc
    except asyncpg.UniqueViolationError as exc:
        raise MultimodalAllianceConflictError(
            "multimodal measurement submission already exists"
        ) from exc
    return {
        "submission_id": submission_id,
        "fusion_record_id": fusion_record_id,
        "result": result.model_dump(mode="json"),
        "idempotent_replay": False,
    }


async def append_deletion_request(
    *,
    principal: Principal,
    session_id: UUID,
    submission_id: UUID,
    scopes: Sequence[str],
    request_reason: str = "learner_request",
) -> dict[str, Any]:
    if principal.role not in {Role.LEARNER, Role.ADMIN}:
        raise MultimodalAllianceStateError(
            "multimodal deletion request requires learner or admin role"
        )
    learner_actor = UUID(principal.user_id)
    deletion_request_id = uuid4()
    async with db.acquire(
        role=principal.role.value,
        user_id=principal.user_id,
        cohort_ids=principal.cohort_ids,
    ) as conn:
        session = await _visible_session(conn, session_id)
        learner_id = UUID(str(_value(session, "learner_id")))
        if principal.role == Role.LEARNER and learner_id != learner_actor:
            raise MultimodalAllianceNotFoundError("session not found or not visible")
        await conn.execute(
            "SELECT pg_advisory_xact_lock(hashtextextended($1::text, 0))",
            f"multimodal-deletion:{session_id}",
        )
        deletion_request_id, replay = await _insert_deletion_request(
            conn,
            submission_id=submission_id,
            deletion_request_id=deletion_request_id,
            session_id=session_id,
            learner_id=learner_id,
            scopes=scopes,
            request_reason=request_reason,
            requested_by_uid=learner_actor,
            created_by_role=principal.role.value,
        )
    return {
        "submission_id": submission_id,
        "deletion_request_id": deletion_request_id,
        "idempotent_replay": replay,
    }


async def request_expired_retention_deletions(
    *,
    conn: asyncpg.Connection,
    as_of: datetime,
    limit: int = 100,
) -> list[dict[str, Any]]:
    """Materialize deterministic deletion work for expired raw audio assets."""

    rows = await conn.fetch(
        """
        SELECT a.audio_asset_id, a.session_id, a.learner_id
        FROM app.multimodal_audio_asset a
        WHERE a.retained_until <= $1
          AND NOT EXISTS (
            SELECT 1 FROM audit.multimodal_deletion_tombstone t
            WHERE t.session_id = a.session_id AND t.scope = 'audio'
          )
        ORDER BY a.retained_until, a.audio_asset_id
        LIMIT $2
        """,
        as_of,
        max(1, min(int(limit), 100)),
    )
    results: list[dict[str, Any]] = []
    for row in rows:
        audio_asset_id = UUID(str(_value(row, "audio_asset_id")))
        session_id = UUID(str(_value(row, "session_id")))
        learner_id = UUID(str(_value(row, "learner_id")))
        submission_id = uuid5(
            NAMESPACE_URL,
            f"vignette:g7:retention-submission:{audio_asset_id}",
        )
        deletion_request_id = uuid5(
            NAMESPACE_URL,
            f"vignette:g7:retention-request:{audio_asset_id}",
        )
        request_id, replay = await _insert_deletion_request(
            conn,
            submission_id=submission_id,
            deletion_request_id=deletion_request_id,
            session_id=session_id,
            learner_id=learner_id,
            scopes=("audio",),
            request_reason="retention_expired",
            requested_by_uid=learner_id,
            created_by_role="evaluator",
        )
        results.append(
            {
                "audio_asset_id": audio_asset_id,
                "submission_id": submission_id,
                "deletion_request_id": request_id,
                "idempotent_replay": replay,
            }
        )
    return results


async def complete_deletion(
    *,
    conn: asyncpg.Connection,
    deletion_request_id: UUID,
    submission_id: UUID,
    tombstones: Sequence[Mapping[str, Any]],
    actor_uid: UUID | None,
    actor_kind: str,
) -> dict[str, Any]:
    request = await conn.fetchrow(
        """
        SELECT deletion_request_id, session_id, learner_id, scopes
        FROM app.multimodal_deletion_request
        WHERE deletion_request_id = $1
        """,
        deletion_request_id,
    )
    if request is None:
        raise MultimodalAllianceNotFoundError(
            "multimodal deletion request not found or not visible"
        )
    requested_scopes = set(_value(request, "scopes", ()))
    ordered_tombstones = tuple(sorted(tombstones, key=lambda item: str(item["scope"])))
    supplied_scopes = {str(item["scope"]) for item in ordered_tombstones}
    if requested_scopes != supplied_scopes or len(supplied_scopes) != len(
        ordered_tombstones
    ):
        raise MultimodalAllianceStateError(
            "deletion completion must prove every requested scope exactly once"
        )
    session_id = UUID(str(_value(request, "session_id")))
    learner_id = UUID(str(_value(request, "learner_id")))
    payload = {
        "deletion_request_id": str(deletion_request_id),
        "tombstones": [dict(item) for item in ordered_tombstones],
        "actor_uid": str(actor_uid) if actor_uid else None,
        "actor_kind": actor_kind,
    }
    content_hash = _canonical_hash(payload)
    await conn.execute(
        "SELECT pg_advisory_xact_lock(hashtextextended($1::text, 0))",
        f"multimodal-deletion-complete:{deletion_request_id}",
    )
    existing = await _existing_request(
        conn,
        submission_id=submission_id,
        request_kind="deletion_completion",
        content_hash=content_hash,
        session_id=session_id,
        learner_id=learner_id,
    )
    if existing is not None:
        existing_rows = await conn.fetch(
            """
            SELECT tombstone_id
            FROM audit.multimodal_deletion_tombstone
            WHERE completion_submission_id = $1
            ORDER BY scope
            """,
            submission_id,
        )
        return {
            "submission_id": submission_id,
            "deletion_request_id": deletion_request_id,
            "tombstone_ids": [
                UUID(str(_value(row, "tombstone_id"))) for row in existing_rows
            ]
            or [existing],
            "idempotent_replay": True,
        }
    tombstone_ids = [uuid4() for _ in ordered_tombstones]
    await _insert_request(
        conn,
        submission_id=submission_id,
        content_hash=content_hash,
        request_kind="deletion_completion",
        session_id=session_id,
        learner_id=learner_id,
        result_id=tombstone_ids[0],
        created_by_role="evaluator" if actor_kind == "retention_worker" else "admin",
    )
    try:
        for tombstone_id, item in zip(tombstone_ids, ordered_tombstones, strict=True):
            await conn.execute(
                """
                INSERT INTO audit.multimodal_deletion_tombstone (
                  tombstone_id, completion_submission_id, deletion_request_id,
                  session_id, learner_id, scope, target_ref_hash,
                  deletion_proof, actor_uid, actor_kind, deleted_at
                ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11)
                """,
                tombstone_id,
                submission_id,
                deletion_request_id,
                session_id,
                learner_id,
                item["scope"],
                item["target_ref_hash"],
                item["deletion_proof"],
                actor_uid,
                actor_kind,
                item["deleted_at"],
            )
    except (asyncpg.CheckViolationError, asyncpg.ForeignKeyViolationError) as exc:
        raise MultimodalAllianceStateError(
            "multimodal deletion proof violated audit invariants"
        ) from exc
    except asyncpg.UniqueViolationError as exc:
        raise MultimodalAllianceConflictError(
            "multimodal deletion scope was already completed"
        ) from exc
    return {
        "submission_id": submission_id,
        "deletion_request_id": deletion_request_id,
        "tombstone_ids": tombstone_ids,
        "idempotent_replay": False,
    }


async def read_session_metadata(
    *, principal: Principal, session_id: UUID
) -> dict[str, Any]:
    async with db.acquire(
        role=principal.role.value,
        user_id=principal.user_id,
        cohort_ids=principal.cohort_ids,
    ) as conn:
        session = await _visible_session(conn, session_id)
        learner_id = UUID(str(_value(session, "learner_id")))
        consent_rows = await conn.fetch(
            """
            SELECT consent_snapshot_id, sequence_no, consent_status, retain_audio,
                   retain_derived_features, transcript_retained, retention_days,
                   policy_version, reason_code, created_at
            FROM app.multimodal_consent_snapshot
            WHERE session_id = $1 ORDER BY sequence_no
            """,
            session_id,
        )
        timeline_rows = await conn.fetch(
            """
            SELECT timeline_id, audio_duration_ms, clock_version, word_count,
                   event_count, created_at, derived_features_available
            FROM app.multimodal_session_metadata_v
            WHERE session_id = $1 ORDER BY created_at
            """,
            session_id,
        )
        derived_available = any(
            bool(_value(row, "derived_features_available")) for row in timeline_rows
        )
        derived_deleted = bool(timeline_rows) and not derived_available
        words: Sequence[Any] = ()
        events: Sequence[Any] = ()
        if derived_available:
            words = await conn.fetch(
                """
                SELECT timeline_id, word_index, start_ms, end_ms, speaker, token_hash
                FROM app.multimodal_word_timestamp
                WHERE session_id = $1 ORDER BY timeline_id, word_index
                """,
                session_id,
            )
            events = await conn.fetch(
                """
                SELECT timeline_id, event_id, event_type, start_ms, end_ms, actor,
                       observed_feature, uncertainty, source, claim_scope,
                       clinical_claim_allowed
                FROM app.multimodal_voice_event
                WHERE session_id = $1 ORDER BY timeline_id, start_ms, event_id
                """,
                session_id,
            )
        measurements = await conn.fetch(
            """
            SELECT measurement_id, axis, modality, status, value, confidence,
                   uncertainty, evidence_refs, model_run_id, instrument_id,
                   instrument_version, model_name, prompt_version, source_kind,
                   error_code, created_at
            FROM app.multimodal_axis_measurement
            WHERE session_id = $1
              AND ($2::boolean = FALSE OR modality = 'text')
            ORDER BY created_at, axis, modality
            """,
            session_id,
            derived_deleted,
        )
        fusions = await conn.fetch(
            """
            SELECT fusion_record_id, axis, status, value, uncertainty,
                   modalities_used, measurement_ids, fusion_applied,
                   calibration_id, benchmark_version, incremental_gain,
                   counterevidence, created_at
            FROM app.multimodal_fusion_decision
            WHERE session_id = $1
              AND ($2::boolean = FALSE OR NOT ('voice' = ANY(modalities_used)))
            ORDER BY created_at, axis
            """,
            session_id,
            derived_deleted,
        )
        deletions = await conn.fetch(
            """
            SELECT r.deletion_request_id, r.scopes, r.request_reason, r.requested_at,
                   COALESCE(array_agg(t.scope ORDER BY t.scope)
                     FILTER (WHERE t.scope IS NOT NULL), '{}') AS completed_scopes
            FROM app.multimodal_deletion_request r
            LEFT JOIN audit.multimodal_deletion_tombstone t
              ON t.deletion_request_id = r.deletion_request_id
            WHERE r.session_id = $1
            GROUP BY r.deletion_request_id, r.scopes, r.request_reason, r.requested_at
            ORDER BY r.requested_at
            """,
            session_id,
        )
    return {
        "session_id": session_id,
        "learner_id": learner_id,
        "clinical_claim_allowed": False,
        "consent_snapshots": [dict(row) for row in consent_rows],
        "timelines": [dict(row) for row in timeline_rows],
        "word_timestamps": [dict(row) for row in words],
        "voice_events": [dict(row) for row in events],
        "measurements": [dict(row) for row in measurements],
        "fusion_decisions": [dict(row) for row in fusions],
        "deletion_requests": [dict(row) for row in deletions],
    }


async def read_raw_audio_access(
    *, principal: Principal, session_id: UUID
) -> list[dict[str, Any]]:
    if principal.role not in {Role.LEARNER, Role.ADMIN}:
        raise MultimodalAllianceStateError(
            "raw audio access is limited to the learner and administrator"
        )
    async with db.acquire(
        role=principal.role.value,
        user_id=principal.user_id,
        cohort_ids=principal.cohort_ids,
    ) as conn:
        await _visible_session(conn, session_id)
        rows = await conn.fetch(
            """
            SELECT audio_asset_id, session_id, learner_id, audio_ref, audio_sha256,
                   media_type, byte_size, duration_ms, retained_until, created_at
            FROM app.multimodal_raw_audio_access_v
            WHERE session_id = $1 ORDER BY created_at
            """,
            session_id,
        )
    return [dict(row) for row in rows]


async def read_raw_audio_asset(
    *, principal: Principal, session_id: UUID, audio_asset_id: UUID
) -> dict[str, Any]:
    """Return one consent-valid raw-audio storage handle behind learner/admin RLS."""

    if principal.role not in {Role.LEARNER, Role.ADMIN}:
        raise MultimodalAllianceStateError(
            "raw audio access is limited to the learner and administrator"
        )
    async with db.acquire(
        role=principal.role.value,
        user_id=principal.user_id,
        cohort_ids=principal.cohort_ids,
    ) as conn:
        await _visible_session(conn, session_id)
        row = await conn.fetchrow(
            """
            SELECT audio_asset_id, session_id, learner_id, audio_ref, audio_sha256,
                   media_type, byte_size, duration_ms, retained_until, created_at
            FROM app.multimodal_raw_audio_access_v
            WHERE session_id = $1 AND audio_asset_id = $2
            """,
            session_id,
            audio_asset_id,
        )
    if row is None:
        raise MultimodalAllianceNotFoundError(
            "raw audio asset not found, expired, or deleted"
        )
    return dict(row)


__all__ = [
    "MultimodalAllianceConflictError",
    "MultimodalAllianceNotFoundError",
    "MultimodalAllianceStateError",
    "MultimodalConsentRequiredError",
    "MultimodalConsentWithdrawnError",
    "append_consent_snapshot",
    "append_deletion_request",
    "append_measurement_fusion",
    "append_runtime_timeline",
    "append_timeline",
    "assert_voice_processing_allowed",
    "complete_deletion",
    "read_raw_audio_access",
    "read_raw_audio_asset",
    "read_session_metadata",
    "request_expired_retention_deletions",
]