#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
app/core/qdrant_points.py

Zweck
- Gemeinsame Helfer zum Erzeugen von Qdrant-Points für Notes, Chunks und Edges.
- Abwärtskompatibel zu altem Edge-Payload-Schema aus edges.py:
    - alt: {'edge_type','src_id','dst_id', ...}
    - neu: {'kind','source_id','target_id', ...}
- **NEU (v1.4.0):** Re-Exports/Wrapper für Legacy-Importer:
    * ensure_collections_for_prefix(...) → delegiert an app.core.qdrant.ensure_collections_for_prefix
    * collection_names(...)              → delegiert an app.core.qdrant.collection_names

Version
- 1.4.0 (2025-11-08)

Aufruf / Verwendung
- Wird von Import-/Backfill-Skripten via:
    from app.core.qdrant_points import (
        points_for_note, points_for_chunks, points_for_edges, upsert_batch,
        ensure_collections_for_prefix, collection_names
    )
  eingebunden. Keine CLI.
"""
from __future__ import annotations
import uuid
from typing import List, Tuple, Optional, Iterable, Dict, Any

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

# Delegation an app.core.qdrant, um Kompatibilität sicherzustellen
try:
    from app.core.qdrant import (
        ensure_collections_for_prefix as _ensure_cols_legacy,
        collection_names as _collection_names,
    )
except Exception:
    _ensure_cols_legacy = None
    _collection_names = None


# -------------------------------
# Utility
# -------------------------------
def _names(prefix: str) -> Tuple[str, str, str]:
    if _collection_names:
        return _collection_names(prefix)
    return f"{prefix}_notes", f"{prefix}_chunks", f"{prefix}_edges"

def _to_uuid(stable_key: str) -> str:
    """Stabile UUIDv5 aus einem String-Key (deterministisch)."""
    return str(uuid.uuid5(uuid.NAMESPACE_URL, stable_key))


# -------------------------------
# Public API (Points)
# -------------------------------
def points_for_note(
    prefix: str,
    note_payload: dict,
    note_vec: List[float] | None,
    dim: int,
) -> Tuple[str, List[rest.PointStruct]]:
    """Notes-Collection: falls kein Note-Embedding -> Nullvektor der Länge dim."""
    notes_col, _, _ = _names(prefix)
    vector = note_vec if note_vec is not None else [0.0] * int(dim)
    raw_note_id = note_payload.get("note_id") or note_payload.get("id") or "missing-note-id"
    point_id = _to_uuid(raw_note_id)
    pt = rest.PointStruct(id=point_id, vector=vector, payload=note_payload)
    return notes_col, [pt]


def points_for_chunks(
    prefix: str,
    chunk_payloads: List[dict],
    vectors: List[List[float]],
) -> Tuple[str, List[rest.PointStruct]]:
    """
    Chunks-Collection: erwartet pro Chunk einen Vektor.
    Robustheit:
      - Fehlt 'chunk_id', nutze 'id', sonst baue '${note_id}#${i}' (1-basiert).
      - Schreibe die abgeleitete ID zurück in die Payload (pl['chunk_id']).
    """
    _, chunks_col, _ = _names(prefix)
    points: List[rest.PointStruct] = []
    for i, (pl, vec) in enumerate(zip(chunk_payloads, vectors), start=1):
        chunk_id = pl.get("chunk_id") or pl.get("id")
        if not chunk_id:
            note_id = pl.get("note_id") or pl.get("parent_note_id") or "missing-note"
            chunk_id = f"{note_id}#{i}"
            pl["chunk_id"] = chunk_id
        point_id = _to_uuid(chunk_id)
        points.append(rest.PointStruct(id=point_id, vector=vec, payload=pl))
    return chunks_col, points


def _normalize_edge_payload(pl: dict) -> dict:
    """
    Sorgt für kompatible Feldnamen.
    akzeptiert:
      - neu: kind, source_id, target_id, seq?
      - alt: edge_type, src_id,  dst_id,   order?/index?
    schreibt zurück: kind, source_id, target_id, seq?
    """
    kind = pl.get("kind") or pl.get("edge_type") or "edge"
    source_id = pl.get("source_id") or pl.get("src_id") or "unknown-src"
    target_id = pl.get("target_id") or pl.get("dst_id") or "unknown-tgt"
    seq = pl.get("seq") or pl.get("order") or pl.get("index")

    # in Payload zurückschreiben (ohne alte Felder zu entfernen → maximal kompatibel)
    pl.setdefault("kind", kind)
    pl.setdefault("source_id", source_id)
    pl.setdefault("target_id", target_id)
    if seq is not None and "seq" not in pl:
        pl["seq"] = seq
    return pl


def points_for_edges(prefix: str, edge_payloads: List[dict]) -> Tuple[str, List[rest.PointStruct]]:
    """
    Edges-Collection mit 1D-Dummy-Vektor.
    - Akzeptiert sowohl neues als auch altes Edge-Schema (siehe _normalize_edge_payload).
    - Fehlt 'edge_id', wird sie stabil aus (kind, source_id, target_id, seq) konstruiert.
    """
    _, _, edges_col = _names(prefix)
    points: List[rest.PointStruct] = []
    for raw in edge_payloads:
        pl = _normalize_edge_payload(raw)

        edge_id = pl.get("edge_id")
        if not edge_id:
            kind = pl.get("kind", "edge")
            s = pl.get("source_id", "unknown-src")
            t = pl.get("target_id", "unknown-tgt")
            seq = pl.get("seq") or ""
            edge_id = f"{kind}:{s}->{t}#{seq}"
            pl["edge_id"] = edge_id

        point_id = _to_uuid(edge_id)
        points.append(rest.PointStruct(id=point_id, vector=[0.0], payload=pl))
    return edges_col, points


def upsert_batch(client: QdrantClient, collection: str, points: List[rest.PointStruct]) -> None:
    if not points:
        return
    client.upsert(collection_name=collection, points=points, wait=True)


# -------------------------------
# NEU: Legacy-Wrapper (Re-Exports)
# -------------------------------
def ensure_collections_for_prefix(client: QdrantClient, prefix: str, dim: int, destructive: bool = False) -> Tuple[str, str, str]:
    """
    Für ältere Importer, die diese Funktion aus qdrant_points importieren.
    Delegiert an app.core.qdrant.ensure_collections_for_prefix (falls vorhanden),
    sonst minimaler Fallback via local _names(..).
    """
    if _ensure_cols_legacy:
        return _ensure_cols_legacy(client, prefix, dim, destructive=destructive)
    # Fallback: keine Seiteneffekte, nur Namen liefern (Collections sollten vorher existieren)
    return _names(prefix)


# -------------------------------
# WP-04 Helfer (Suche/Graph) — unverändert zu v1.3, hier nur der Vollständigkeit halber
# -------------------------------
def _filter_any(field: str, values: Iterable[str]) -> rest.Filter:
    """Erzeuge OR-Filter: payload[field] == any(values)."""
    return rest.Filter(
        should=[
            rest.FieldCondition(key=field, match=rest.MatchValue(value=str(v)))
            for v in values
        ]
    )

def _merge_filters(*filters: Optional[rest.Filter]) -> Optional[rest.Filter]:
    """Fasst mehrere Filter zu einem AND zusammen (None wird ignoriert)."""
    fs = [f for f in filters if f is not None]
    if not fs:
        return None
    if len(fs) == 1:
        return fs[0]
    must = []
    for f in fs:
        if getattr(f, "must", None):
            must.extend(f.must)
        if getattr(f, "should", None):
            must.append(rest.Filter(should=f.should))
        if getattr(f, "must_not", None):
            # Negative Bedingungen beibehalten
            if isinstance(f.must_not, list) and f.must_not:
                if not hasattr(_merge_filters, "_warned"):
                    _merge_filters._warned = True  # type: ignore[attr-defined]
            # Qdrant erlaubt must_not auf Top-Level; hier nicht zusammengeführt
    return rest.Filter(must=must)

def _filter_from_dict(filters: Optional[Dict[str, Any]]) -> Optional[rest.Filter]:
    if not filters:
        return None
    parts = []
    for k, v in filters.items():
        if isinstance(v, (list, tuple, set)):
            parts.append(_filter_any(k, [str(x) for x in v]))
        else:
            parts.append(rest.Filter(must=[rest.FieldCondition(key=k, match=rest.MatchValue(value=str(v)))]))
    return _merge_filters(*parts)

def search_chunks_by_vector(
    client: QdrantClient,
    prefix: str,
    vector: list[float],
    top: int = 10,
    filters: Optional[Dict[str, Any]] = None,
) -> list[tuple[str, float, dict]]:
    """
    Vektorielle Suche in {prefix}_chunks.
    Rückgabe: Liste von (point_id, score, payload)
    """
    _, chunks_col, _ = _names(prefix)
    flt = _filter_from_dict(filters)
    res = client.search(
        collection_name=chunks_col,
        query_vector=vector,
        limit=top,
        with_payload=True,
        with_vectors=False,
        query_filter=flt,
    )
    out: list[tuple[str, float, dict]] = []
    for r in res:
        out.append((str(r.id), float(r.score), dict(r.payload or {})))
    return out

def get_edges_for_sources(
    client: QdrantClient,
    prefix: str,
    source_ids: list[str],
    edge_types: Optional[list[str]] = None,
    limit: int = 2048,
) -> list[dict]:
    """
    Hole Edges aus {prefix}_edges mit source_id ∈ source_ids (und optional kind ∈ edge_types).
    Liefert Payload-Dicts inkl. edge_id/source_id/target_id/kind/seq (falls vorhanden).
    """
    _, _, edges_col = _names(prefix)
    f_src = _filter_any("source_id", source_ids)
    f_kind = _filter_any("kind", edge_types) if edge_types else None
    flt = _merge_filters(f_src, f_kind)

    collected: list[dict] = []
    next_page = None
    while True:
        points, next_page = client.scroll(
            collection_name=edges_col,
            scroll_filter=flt,
            limit=min(512, limit - len(collected)),
            with_payload=True,
            with_vectors=False,
            offset=next_page,
        )
        for p in points:
            pl = dict(p.payload or {})
            pl.setdefault("id", str(p.id))
            collected.append(pl)
            if len(collected) >= limit:
                return collected
        if next_page is None:
            break
    return collected

def get_note_payload(
    client: QdrantClient,
    prefix: str,
    note_id: str,
) -> Optional[dict]:
    """
    Hole eine Note anhand ihres payload.note_id (nicht internal UUID!).
    """
    notes_col, _, _ = _names(prefix)
    flt = rest.Filter(must=[rest.FieldCondition(key="note_id", match=rest.MatchValue(value=note_id))])
    points, _ = client.scroll(
        collection_name=notes_col,
        scroll_filter=flt,
        limit=1,
        with_payload=True,
        with_vectors=False,
    )
    if not points:
        return None
    pl = dict(points[0].payload or {})
    pl.setdefault("id", str(points[0].id))
    return pl

def get_neighbor_nodes(
    client: QdrantClient,
    prefix: str,
    target_ids: list[str],
    limit_per_collection: int = 2048,
) -> dict[str, dict]:
    """
    Hole Payloads der Zielknoten (Notes/Chunks) zu den angegebenen IDs.
    IDs sind die stabilen payload-IDs (note_id/chunk_id), nicht internal UUIDs.
    Rückgabe: Mapping target_id -> payload
    """
    notes_col, chunks_col, _ = _names(prefix)
    out: dict[str, dict] = {}

    # Notes
    flt_notes = _filter_any("note_id", target_ids)
    next_page = None
    while True:
        pts, next_page = client.scroll(
            collection_name=notes_col,
            scroll_filter=flt_notes,
            limit=256,
            with_payload=True,
            with_vectors=False,
            offset=next_page,
        )
        for p in pts:
            pl = dict(p.payload or {})
            nid = pl.get("note_id")
            if nid and nid not in out:
                pl.setdefault("id", str(p.id))
                out[nid] = pl
        if next_page is None or len(out) >= limit_per_collection:
            break

    # Chunks
    flt_chunks = _filter_any("chunk_id", target_ids)
    next_page = None
    while True:
        pts, next_page = client.scroll(
            collection_name=chunks_col,
            scroll_filter=flt_chunks,
            limit=256,
            with_payload=True,
            with_vectors=False,
            offset=next_page,
        )
        for p in pts:
            pl = dict(p.payload or {})
            cid = pl.get("chunk_id")
            if cid and cid not in out:
                pl.setdefault("id", str(p.id))
                out[cid] = pl
        if next_page is None or len(out) >= limit_per_collection:
            break

    return out