"""Atlas semantic core for entity resolution and enrichment."""

from __future__ import annotations

from datetime import datetime, timezone

from app.cache import EntityCache
from app.entity_normalize import normalize_entity
from app.ids import claim_hash, entity_hash
from app.models import (
    AtlasAlias,
    AtlasClaim,
    AtlasClaimObject,
    AtlasEntity,
    AtlasEnrichmentDataset,
    AtlasProvenance,
)
from app.trends_resolution import resolve_entity_via_trends
from app.type_classifier import TypeClassification, classify_entity_type
from app.storage_service import AtlasStorageService
from app.virtuoso_store import VirtuosoEntityStore
from app.wikidata_lookup import lookup_wikidata

_entity_cache = EntityCache(max_entries=512)
_virtuoso_store = VirtuosoEntityStore(max_cache_entries=256)
_storage = AtlasStorageService()


def _now_date() -> str:
    return datetime.now(timezone.utc).date().isoformat()


async def resolve_entity(subject: str, context: str | None = None) -> AtlasEntity:
    normalized = normalize_entity(subject)
    token = normalized.strip().lower()
    cached = _entity_cache.get(token)
    if cached is not None:
        try:
            await _storage.write_entity(cached)
        except Exception:
            pass
        return cached

    virt_hit = await _virtuoso_store.lookup(token)
    if virt_hit is not None:
        # Make the returned raw payload reflect the original caller input
        # (so tests and UI/debug output stay stable).
        if isinstance(virt_hit.raw_payload, dict):
            virt_hit.raw_payload.setdefault("source", "virtuoso")
            virt_hit.raw_payload["raw"] = subject
            virt_hit.raw_payload["normalized"] = normalized
        _entity_cache.store(virt_hit, extra_tokens=[subject, normalized])
        try:
            await _storage.write_entity(virt_hit)
        except Exception:
            pass
        return virt_hit

    resolution = resolve_entity_via_trends(subject)
    classification = await classify_entity_type(subject, resolution, context)
    wikidata = await lookup_wikidata(subject)
    entity = _entity_from_resolution(subject, resolution, classification, wikidata)
    _entity_cache.store(entity, extra_tokens=[subject, normalized])
    try:
        await _storage.write_entity(entity)
    except Exception:
        pass
    return entity


def _entity_from_resolution(subject: str, resolution: dict, classification: TypeClassification, wikidata: dict | None = None) -> AtlasEntity:
    canonical_label = (
        resolution.get("canonical_label")
        or resolution.get("normalized")
        or subject.strip()
    )

    canonical_type = (
        classification.canonical_type
        or resolution.get("type")
        or "unknown"
    )

    # atlas_id is opaque identity: hash-part only, never semantic content.
    atlas_id = f"atlas:{entity_hash((resolution.get('mid') or '').strip(), (wikidata or {}).get('qid') or '', canonical_label.strip().lower())}"

    trends_prov = AtlasProvenance(
        source=resolution.get("source") or "resolver",
        retrieval_method="trends-resolution",
        confidence=0.9 if resolution.get("mid") else 0.3,
        retrieved_at=resolution.get("retrieved_at"),
    )
    wikidata_prov = (
        AtlasProvenance(
            source="wikidata",
            retrieval_method="wbsearchentities + entitydata",
            confidence=0.99,
            retrieved_at=wikidata.get("retrieved_at"),
        )
        if wikidata and wikidata.get("qid")
        else None
    )

    claims: list[AtlasClaim] = []
    mid = resolution.get("mid")
    if mid:
        claims.append(
            AtlasClaim(
                claim_id=f"clm_raw_ident_mid_{claim_hash(atlas_id, 'atlas:hasIdentifier', mid, 'raw')}",
                subject=atlas_id,
                predicate="atlas:hasIdentifier",
                object=AtlasClaimObject(kind="identifier", id_type="mid", value=mid),
                layer="raw",
                provenance=trends_prov,
                created_at=_now_date(),
            )
        )
    if wikidata and wikidata.get("qid"):
        claims.append(
            AtlasClaim(
                claim_id=f"clm_raw_ident_qid_{claim_hash(atlas_id, 'atlas:hasIdentifier', wikidata['qid'], 'raw')}",
                subject=atlas_id,
                predicate="atlas:hasIdentifier",
                object=AtlasClaimObject(kind="identifier", id_type="qid", value=wikidata["qid"]),
                layer="raw",
                provenance=wikidata_prov,
                created_at=_now_date(),
            )
        )

    claims.append(
            AtlasClaim(
            claim_id=f"clm_drv_canonical_type_{claim_hash(atlas_id, 'atlas:hasCanonicalType', canonical_type, 'derived')}",
            subject=atlas_id,
            predicate="atlas:hasCanonicalType",
            object=AtlasClaimObject(kind="type", value=f"atlas:{canonical_type}"),
            layer="derived",
            provenance=classification.provenance,
            created_at=_now_date(),
        )
    )

    payload = dict(resolution)
    if wikidata:
        payload["wikidata"] = {
            "wikidata_status": "hit",
            "source": "wikidata",
            "qid": wikidata.get("qid"),
            "label": wikidata.get("label"),
            "description": wikidata.get("description"),
            "retrieved_at": wikidata.get("retrieved_at"),
        }
    else:
        payload["wikidata"] = {"wikidata_status": "missing", "source": "wikidata", "retrieved_at": None}

    return AtlasEntity(
        atlas_id=atlas_id,
        canonical_label=canonical_label,
        canonical_description=(wikidata or {}).get("description"),
        entity_type=canonical_type,
        aliases=[AtlasAlias(label=subject.strip() or canonical_label)],
        claims=claims,
        raw_payload=payload,
        needs_curation=classification.needs_curation,
    )


def enrich_entity(entity: AtlasEntity, constraints=None, depth: int = 1) -> AtlasEnrichmentDataset:
    return AtlasEnrichmentDataset(
        seed_entity=entity,
        related_entities=[],
        query_context=constraints or {},
        depth=depth,
    )