#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Script:    scripts/import_markdown.py
Version:   0.6.0 (2025-09-06)
Autor:     mindnet / Architektur Datenimporte & Sync

Kurzbeschreibung
---------------
Importiert Markdown-Notizen aus einem Obsidian-ähnlichen Vault in Qdrant:
- Validiert Frontmatter / Note-Payload.
- Chunking + Embeddings.
- Leitet Edges direkt beim Import aus [[Wikilinks]] ab:
  - 'references' (Note→Note)
  - 'references_at' (Chunk→Note)
  - 'backlink' (Note←Note) nur für Note→Note-Kanten.

Neu in 0.6.0
------------
- Option `--purge-before-upsert`: löscht für die jeweils verarbeitete Note
  *vor* dem Upsert alle zugehörigen Chunks und Edges in Qdrant (selektiv!),
  um Leichen nach Re-Chunking zu vermeiden.
- Robuste Link-Auflösung via Note-Index (ID / Titel-Slug / Datei-Slug)
  konsistent zu `derive_edges.py`.

Aufrufbeispiele
---------------
Dry-Run (keine Schreibzugriffe):
    python3 -m scripts.import_markdown --vault ./vault

Nur eine bestimmte Note:
    python3 -m scripts.import_markdown --vault ./vault --note-id 20250821-foo

Apply (schreiben) mit Purge:
    python3 -m scripts.import_markdown --vault ./vault --apply --purge-before-upsert

Parameter
---------
--vault PATH                 : Pflicht. Root-Verzeichnis des Vaults.
--apply                      : Wenn gesetzt, werden Upserts durchgeführt (sonst Dry-Run).
--purge-before-upsert        : Wenn gesetzt, werden vor dem Upsert (nur bei --apply)
                               alte Chunks und Edges dieser Note in Qdrant gelöscht.
--note-id ID                 : Optional, verarbeitet nur diese eine Note.

Umgebungsvariablen (.env)
-------------------------
QDRANT_URL, QDRANT_API_KEY, COLLECTION_PREFIX, VECTOR_DIM
Standard: url=http://127.0.0.1:6333, prefix=mindnet, dim=384

Kompatibilität
--------------
- Nutzt die bestehenden Kernmodule:
  app.core.parser              (read_markdown, normalize_frontmatter, validate_required_frontmatter)
  app.core.validate_note       (validate_note_payload)
  app.core.chunker             (assemble_chunks)
  app.core.chunk_payload       (make_chunk_payloads)
  app.core.embed               (embed_texts)
  app.core.qdrant              (QdrantConfig, get_client, ensure_collections)
  app.core.qdrant_points       (points_for_note, points_for_chunks, points_for_edges, upsert_batch)
  app.core.derive_edges        (build_note_index, derive_wikilink_edges)

Änderungshinweise vs. früherer Importer
---------------------------------------
- Alte, globale Lösch-Workarounds entfallen. Selektives Purge ist jetzt optional und sicher.
- Edges werden nur noch in der neuen, einheitlichen Struktur erzeugt.
"""

from __future__ import annotations
import argparse
import glob
import json
import os
import sys
from typing import List, Dict

from dotenv import load_dotenv
from qdrant_client.http import models as rest

# Kern-Bausteine (vorhanden in eurem Projekt)
from app.core.parser import (
    read_markdown,
    normalize_frontmatter,
    validate_required_frontmatter,
)
from app.core.validate_note import validate_note_payload
from app.core.chunker import assemble_chunks
from app.core.chunk_payload import make_chunk_payloads
from app.core.embed import embed_texts
from app.core.qdrant import QdrantConfig, ensure_collections, get_client, collection_names
from app.core.qdrant_points import (
    points_for_note,
    points_for_chunks,
    points_for_edges,
    upsert_batch,
)
from app.core.derive_edges import build_note_index, derive_wikilink_edges


# -------------------------------------------------
# Hilfsfunktionen
# -------------------------------------------------

def iter_md(root: str) -> List[str]:
    patterns = ["**/*.md", "*.md"]
    out: List[str] = []
    for p in patterns:
        out.extend(glob.glob(os.path.join(root, p), recursive=True))
    return sorted(list(dict.fromkeys(out)))  # de-dupe + sort


def make_note_stub(abs_path: str, vault_root: str) -> Dict:
    """
    Erstellt einen minimalen Note-Stub für den Index (build_note_index):
    { note_id, title, path }
    """
    parsed = read_markdown(abs_path)
    fm = normalize_frontmatter(parsed.frontmatter or {})
    # Validierung minimal: wir brauchen id + title (title optional für Slug-Auflösung)
    if "id" not in fm or not fm["id"]:
        raise ValueError(f"Missing id in frontmatter: {abs_path}")
    rel = os.path.relpath(abs_path, vault_root)
    return {"note_id": fm["id"], "title": fm.get("title"), "path": rel}


def build_vault_index(vault_root: str) -> tuple[Dict, Dict, Dict]:
    """
    Liest alle Noten ein und baut den Dreifach-Index für Wikilink-Auflösung.
    """
    files = iter_md(vault_root)
    stubs = []
    for p in files:
        try:
            stubs.append(make_note_stub(p, vault_root))
        except Exception:
            # Notiz ohne id → wird vom Importer später ohnehin übersprungen
            continue
    return build_note_index(stubs)


def purge_for_note(client, prefix: str, note_id: str, chunk_ids: List[str]) -> Dict[str, int]:
    """
    Selektives Purge für die aktuelle Note:
    - Chunks:   alle mit payload.note_id == note_id
    - Edges:    alle mit payload.source_id == note_id ODER == einem der chunk_ids
    - Notes:    werden nicht gelöscht (Upsert überschreibt Payload/Vektor)
    """
    notes_col, chunks_col, edges_col = collection_names(prefix)
    counts = {"chunks_deleted": 0, "edges_deleted": 0}

    # Chunks löschen (Filter must: note_id == X)
    f_chunks = rest.Filter(
        must=[rest.FieldCondition(key="note_id", match=rest.MatchValue(value=note_id))]
    )
    res_chunks = client.delete(collection_name=chunks_col, points_selector=f_chunks, wait=True)
    counts["chunks_deleted"] = getattr(res_chunks, "status", None) and 0 or 0  # Qdrant liefert keine count hier

    # Edges löschen: OR über Note-ID und alle Chunk-IDs
    should_conds = [rest.FieldCondition(key="source_id", match=rest.MatchValue(value=note_id))]
    for cid in chunk_ids:
        should_conds.append(rest.FieldCondition(key="source_id", match=rest.MatchValue(value=cid)))

    f_edges = rest.Filter(should=should_conds) if should_conds else None
    if f_edges is not None:
        client.delete(collection_name=edges_col, points_selector=f_edges, wait=True)

    return counts


# -------------------------------------------------
# Main
# -------------------------------------------------

def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--vault", required=True, help="Pfad zum Vault-Root")
    ap.add_argument("--apply", action="store_true", help="Schreibt in Qdrant (sonst Dry-Run)")
    ap.add_argument(
        "--purge-before-upsert",
        action="store_true",
        help="Vor Upsert alte Chunks/Edges der aktuellen Note löschen (nur mit --apply wirksam).",
    )
    ap.add_argument("--note-id", help="Optional: nur diese Note verarbeiten")
    args = ap.parse_args()

    load_dotenv()
    cfg = QdrantConfig(
        url=os.getenv("QDRANT_URL", "http://127.0.0.1:6333"),
        api_key=os.getenv("QDRANT_API_KEY", None),
        prefix=os.getenv("COLLECTION_PREFIX", "mindnet"),
        dim=int(os.getenv("VECTOR_DIM", "384")),
    )
    client = get_client(cfg)
    ensure_collections(client, cfg.prefix, cfg.dim)

    vault_root = os.path.abspath(args.vault)
    files = iter_md(vault_root)
    if not files:
        print("Keine Markdown-Dateien gefunden.", file=sys.stderr)
        sys.exit(2)

    # 1) Note-Index über den gesamten Vault (für robuste Link-Auflösung)
    note_index = build_vault_index(vault_root)

    processed = 0
    for abs_path in files:
        parsed = read_markdown(abs_path)
        fm = normalize_frontmatter(parsed.frontmatter or {})
        try:
            validate_required_frontmatter(fm)
        except Exception:
            # unvollständige Note überspringen
            continue
        if args.note_id and fm.get("id") != args.note_id:
            continue

        processed += 1

        # --- Note-Payload ---
        from app.core.note_payload import make_note_payload  # lazy import (bestehende Funktion)
        note_pl = make_note_payload(parsed, vault_root=vault_root)
        validate_note_payload(note_pl)

        # --- Chunking & Payloads ---
        chunks = assemble_chunks(fm["id"], parsed.body, fm.get("type", "concept"))
        chunk_pls = make_chunk_payloads(fm, note_pl["path"], chunks)

        # --- Embeddings ---
        texts = [c.get("text") or c.get("content") or "" for c in chunk_pls]
        vectors = embed_texts(texts)

        # --- Edge-Ableitung (direkt) ---
        edges = derive_wikilink_edges(note_pl, chunk_pls, note_index)

        # --- Ausgabe je Note (Entscheidung) ---
        decision = "apply" if args.apply else "dry-run"

        # --- Purge vor Upsert (nur wenn --apply) ---
        if args.apply and args.purge_before_upsert:
            # Chunk-IDs (neu) ermitteln → für Edge-Purge by source_id
            chunk_ids = []
            for i, ch in enumerate(chunk_pls, start=1):
                cid = ch.get("chunk_id") or ch.get("id") or f"{fm['id']}#{i}"
                ch["chunk_id"] = cid  # sicherstellen
                chunk_ids.append(cid)

            purge_for_note(client, cfg.prefix, fm["id"], chunk_ids)

        # --- Upserts (nur bei --apply) ---
        if args.apply:
            # Note
            notes_col, note_pts = points_for_note(cfg.prefix, note_pl, note_vec=None, dim=cfg.dim)
            upsert_batch(client, notes_col, note_pts)

            # Chunks
            chunks_col, chunk_pts = points_for_chunks(cfg.prefix, chunk_pls, vectors)
            upsert_batch(client, chunks_col, chunk_pts)

            # Edges
            edges_col, edge_pts = points_for_edges(cfg.prefix, edges)
            upsert_batch(client, edges_col, edge_pts)

        # Logging pro Note
        print(json.dumps({
            "note_id": fm["id"],
            "title": fm.get("title"),
            "chunks": len(chunk_pls),
            "edges": len(edges),
            "changed": True,     # Hash-/Zeitvergleich kann optional hier ergänzt werden
            "decision": decision,
            "path": note_pl["path"],
        }, ensure_ascii=False))

    print(f"Done. Processed notes: {processed}")


if __name__ == "__main__":
    main()