"""
chunk_payload.py — Mindnet payload builder (Chunks)
Version: 1.3.0 (2025-11-09)

Purpose
-------
Build Qdrant-compatible JSON payloads for *chunks* of a parsed note.
Tolerant to different call signatures and accepts both dict-like and object-like inputs.

Key features
------------
- Reads type defaults from `config/config.yaml` or `config/types.yaml` (same schema).
- Resolves fields with precedence:
    Frontmatter > type-defaults > ENV > fallback.
- Sets per chunk:
    * `note_id`, `note_title`, `type`
    * `retriever_weight` (float)
    * `chunk_profile`    (short|medium|long)
    * `text`             (never empty: falls back to whole note body/text)
    * `order`, `section`, `start`, `end` (if available)
- Backwards-compatible signature: accepts **kwargs to swallow unknown args.

Input
-----
`parsed_note` may be:
  - dict with keys: id, title, body/text, chunks(list), frontmatter(dict), type
  - object with equivalent attributes

Each chunk may be dict-like or object-like with keys/attrs such as:
  id, text, order, section, start, end
"""

from __future__ import annotations

import os
from pathlib import Path
from typing import Any, Dict, List, Optional, Union

try:
    import yaml  # type: ignore
except Exception:  # pragma: no cover
    yaml = None

def _get(obj: Any, key: str, default: Any = None) -> Any:
    if isinstance(obj, dict):
        return obj.get(key, default)
    return getattr(obj, key, default)

def _frontmatter(obj: Any) -> Dict[str, Any]:
    fm = _get(obj, "frontmatter", {}) or {}
    return fm if isinstance(fm, dict) else {}

def _coerce_float(val: Any, default: float) -> float:
    try:
        if val is None:
            return default
        if isinstance(val, (int, float)):
            return float(val)
        if isinstance(val, str) and val.strip():
            return float(val.strip())
    except Exception:
        pass
    return default

def _normalize_chunk_profile(val: Any, fallback: str = "medium") -> str:
    if not isinstance(val, str):
        return fallback
    v = val.strip().lower()
    if v in {"short", "medium", "long"}:
        return v
    return fallback

def _safe_text(s: Any) -> str:
    if s is None:
        return ""
    if isinstance(s, str):
        return s
    return str(s)

def _load_types_config(
    explicit_config: Optional[Dict[str, Any]] = None,
    search_root: Union[str, Path, None] = None,
) -> Dict[str, Any]:
    if explicit_config and isinstance(explicit_config, dict):
        if "types" in explicit_config and isinstance(explicit_config["types"], dict):
            return explicit_config
    if yaml is None:
        return {"types": {}}
    candidates: List[Path] = []
    root = Path(search_root) if search_root else Path.cwd()
    candidates.append(root / "config" / "config.yaml")
    candidates.append(root / "config" / "types.yaml")
    candidates.append(Path.cwd() / "config" / "config.yaml")
    candidates.append(Path.cwd() / "config" / "types.yaml")
    for p in candidates:
        try:
            if p.exists():
                import yaml as _y
                with p.open("r", encoding="utf-8") as f:
                    loaded = _y.safe_load(f) or {}
                    if isinstance(loaded, dict) and isinstance(loaded.get("types"), dict):
                        return {"types": loaded["types"]}
        except Exception:
            continue
    return {"types": {}}

def _type_defaults(note_type: str, cfg: Dict[str, Any]) -> Dict[str, Any]:
    return (cfg.get("types") or {}).get(note_type, {}) if isinstance(cfg, dict) else {}

def make_chunk_payloads(
    parsed_note: Any,
    config: Optional[Dict[str, Any]] = None,
    **kwargs: Any,
) -> List[Dict[str, Any]]:
    search_root = kwargs.get("search_root")
    fm = _frontmatter(parsed_note)
    note_type = fm.get("type") or _get(parsed_note, "type") or "concept"
    note_type = str(note_type).strip().lower()

    cfg = _load_types_config(config, search_root)
    defaults = _type_defaults(note_type, cfg)

    # Resolve retriever_weight: FM > type-defaults > ENV > 1.0
    rw = fm.get("retriever_weight")
    if rw is None:
        rw = defaults.get("retriever_weight")
    if rw is None:
        env_rw = os.getenv("MINDNET_DEFAULT_RETRIEVER_WEIGHT")
        rw = _coerce_float(env_rw, 1.0)
    else:
        rw = _coerce_float(rw, 1.0)

    # Resolve chunk_profile: FM > type-defaults > ENV > medium
    cp = fm.get("chunk_profile")
    if cp is None:
        cp = defaults.get("chunk_profile")
    if cp is None:
        cp = os.getenv("MINDNET_DEFAULT_CHUNK_PROFILE", "medium")
    cp = _normalize_chunk_profile(cp, "medium")

    note_id = _get(parsed_note, "id")
    note_title = _get(parsed_note, "title")
    body = _get(parsed_note, "body") or _get(parsed_note, "text") or ""

    items = _get(parsed_note, "chunks") or []
    payloads: List[Dict[str, Any]] = []

    if not items:
        items = [{
            "id": f"{note_id}::0" if note_id else None,
            "text": body,
            "order": 0,
            "section": None,
            "start": 0,
            "end": len(body) if isinstance(body, str) else None,
        }]

    for ch in items:
        text = _safe_text(_get(ch, "text"))
        if not text:
            text = _safe_text(body)

        payload = {
            "note_id": note_id,
            "note_title": note_title,
            "type": note_type,
            "retriever_weight": float(rw),
            "chunk_profile": cp,
            "text": text,
            "order": _get(ch, "order"),
            "section": _get(ch, "section"),
            "start": _get(ch, "start"),
            "end": _get(ch, "end"),
            "chunk_id": _get(ch, "id"),
        }
        payload = {k: v for k, v in payload.items() if v is not None}
        payloads.append(payload)

    return payloads