"""
Vector-Store-Wrapper um Qdrant.

Eine Collection "aria_memory" haelt ALLE Memory-Punkte.
Trennung nach Type/Pinned-Status via Payload-Filter.

Punkt-Schema (Payload):
    type      — identity | rule | preference | tool | skill | fact | conversation | reminder
    category  — frei, fuer UI-Gruppierung
    title     — kurze Ueberschrift
    content   — eigentlicher Text (wird embedded)
    pinned    — bool, True = Hot Memory (immer in Prompt)
    source    — import | conversation | manual
    tags      — Liste von Strings
    created_at, updated_at — ISO-Strings
    conversation_id — optional, nur fuer type=conversation
"""

from __future__ import annotations

import logging
import uuid
from dataclasses import dataclass, field
from datetime import datetime, timezone
from enum import Enum
from typing import List, Optional

from qdrant_client import QdrantClient
from qdrant_client.http import models as qm

from .embedder import VECTOR_DIM

logger = logging.getLogger(__name__)

COLLECTION = "aria_memory"


class MemoryType(str, Enum):
    IDENTITY = "identity"
    RULE = "rule"
    PREFERENCE = "preference"
    TOOL = "tool"
    SKILL = "skill"
    FACT = "fact"
    CONVERSATION = "conversation"
    REMINDER = "reminder"


@dataclass
class MemoryPoint:
    id: str
    type: str
    title: str
    content: str
    pinned: bool = False
    category: str = ""
    source: str = "manual"
    tags: List[str] = field(default_factory=list)
    created_at: str = ""
    updated_at: str = ""
    conversation_id: Optional[str] = None
    score: Optional[float] = None  # nur bei Search gesetzt

    def to_payload(self) -> dict:
        p = {
            "type": self.type,
            "title": self.title,
            "content": self.content,
            "pinned": self.pinned,
            "category": self.category,
            "source": self.source,
            "tags": self.tags,
            "created_at": self.created_at,
            "updated_at": self.updated_at,
        }
        if self.conversation_id:
            p["conversation_id"] = self.conversation_id
        return p

    @classmethod
    def from_qdrant(cls, point) -> "MemoryPoint":
        payload = point.payload or {}
        return cls(
            id=str(point.id),
            type=payload.get("type", "fact"),
            title=payload.get("title", ""),
            content=payload.get("content", ""),
            pinned=payload.get("pinned", False),
            category=payload.get("category", ""),
            source=payload.get("source", "manual"),
            tags=payload.get("tags", []),
            created_at=payload.get("created_at", ""),
            updated_at=payload.get("updated_at", ""),
            conversation_id=payload.get("conversation_id"),
            score=getattr(point, "score", None),
        )


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


class VectorStore:
    def __init__(self, host: str, port: int = 6333):
        self.client = QdrantClient(host=host, port=port)
        self._ensure_collection()

    def _ensure_collection(self):
        existing = [c.name for c in self.client.get_collections().collections]
        if COLLECTION not in existing:
            logger.info("Erstelle Collection %s ...", COLLECTION)
            self.client.create_collection(
                collection_name=COLLECTION,
                vectors_config=qm.VectorParams(size=VECTOR_DIM, distance=qm.Distance.COSINE),
            )
            # Indexe fuer typische Filter-Felder
            for field_name in ("type", "pinned", "category", "source", "migration_key"):
                self.client.create_payload_index(
                    collection_name=COLLECTION,
                    field_name=field_name,
                    field_schema=qm.PayloadSchemaType.KEYWORD if field_name != "pinned"
                    else qm.PayloadSchemaType.BOOL,
                )

    # ─── Schreib-Operationen ─────────────────────────────────────────

    def upsert(self, point: MemoryPoint, vector: List[float]) -> str:
        if not point.id:
            point.id = str(uuid.uuid4())
        if not point.created_at:
            point.created_at = _now()
        point.updated_at = _now()

        self.client.upsert(
            collection_name=COLLECTION,
            points=[qm.PointStruct(id=point.id, vector=vector, payload=point.to_payload())],
        )
        return point.id

    def delete(self, point_id: str):
        self.client.delete(
            collection_name=COLLECTION,
            points_selector=qm.PointIdsList(points=[point_id]),
        )

    # ─── Lese-Operationen ────────────────────────────────────────────

    def get(self, point_id: str) -> Optional[MemoryPoint]:
        result = self.client.retrieve(collection_name=COLLECTION, ids=[point_id], with_payload=True)
        if not result:
            return None
        return MemoryPoint.from_qdrant(result[0])

    def list_pinned(self) -> List[MemoryPoint]:
        """Alle pinned Punkte — Hot Memory."""
        return self._scroll(filter=qm.Filter(must=[
            qm.FieldCondition(key="pinned", match=qm.MatchValue(value=True))
        ]))

    def list_by_type(self, type_: str, limit: int = 100) -> List[MemoryPoint]:
        return self._scroll(
            filter=qm.Filter(must=[
                qm.FieldCondition(key="type", match=qm.MatchValue(value=type_))
            ]),
            limit=limit,
        )

    def list_all(self, limit: int = 1000) -> List[MemoryPoint]:
        return self._scroll(filter=None, limit=limit)

    def _scroll(self, filter, limit: int = 1000) -> List[MemoryPoint]:
        points, _ = self.client.scroll(
            collection_name=COLLECTION,
            scroll_filter=filter,
            limit=limit,
            with_payload=True,
            with_vectors=False,
        )
        return [MemoryPoint.from_qdrant(p) for p in points]

    def search(
        self,
        query_vector: List[float],
        k: int = 5,
        type_filter: Optional[str] = None,
        exclude_pinned: bool = True,
        score_threshold: Optional[float] = None,
    ) -> List[MemoryPoint]:
        """Semantische Search. Standard: pinned-Punkte ausgeschlossen
        (die kommen separat via list_pinned in den Prompt).

        score_threshold: nur Treffer mit Cosine-Similarity >= Schwelle
        zurueckgeben. None = keine Filterung. MiniLM-multilingual liefert
        typischerweise 0.3-0.6 fuer relevante Treffer; <0.25 ist Rauschen."""
        must = []
        must_not = []
        if type_filter:
            must.append(qm.FieldCondition(key="type", match=qm.MatchValue(value=type_filter)))
        if exclude_pinned:
            must_not.append(qm.FieldCondition(key="pinned", match=qm.MatchValue(value=True)))

        flt = qm.Filter(must=must or None, must_not=must_not or None)

        results = self.client.search(
            collection_name=COLLECTION,
            query_vector=query_vector,
            query_filter=flt if (must or must_not) else None,
            limit=k,
            with_payload=True,
            score_threshold=score_threshold,
        )
        return [MemoryPoint.from_qdrant(p) for p in results]

    def count(self) -> int:
        return self.client.count(collection_name=COLLECTION, exact=True).count