"""Bridge to raras-app graph-ml artifacts.

raras-app trains PhenoGNet monthly and writes:
    /Users/dimas/raras-app/data/graph-ml/biolord_embeddings.npz   (768-dim, init)
    /Users/dimas/raras-app/data/graph-ml/graph_embeddings.npz     (64-dim, contrastive GNN)
    /Users/dimas/raras-app/data/graph-ml/fused_embeddings.npz     (3072-dim, final, Neo4j-indexed)
    /Users/dimas/raras-app/data/graph-ml/node_ids.json            (index → ORPHA/HPO/HGNC)
    /Users/dimas/raras-app/data/graph-ml/hetero_graph.json        (edges adjacency)

Gemeo loads these read-only. We never retrain inside swarm-py — retrain
runs in raras-app's `retrain-scheduled.sh` cron. Phase-2 GNN training
lives in `gemeo/train/` and writes its own artifacts under `gemeo/artifacts/`.
"""
from __future__ import annotations
import os
import json
import logging
from functools import lru_cache
from typing import Optional

logger = logging.getLogger("gemeo.bridge")

# Default location — env override allowed.
# Priority:
#   1. RARAS_APP_GRAPH_ML env (dev / custom location with full fp64 artifacts)
#   2. ./gemeo/data (the fp16 bundle shipped with the repo, ~54 MB)
#   3. /Users/dimas/raras-app/data/graph-ml (dev fallback for the original fp64)
_REPO_DATA = os.path.join(os.path.dirname(os.path.abspath(__file__)), "data")
RARAS_APP_GRAPH_ML = os.environ.get(
    "RARAS_APP_GRAPH_ML",
    _REPO_DATA if os.path.exists(_REPO_DATA) else "/Users/dimas/raras-app/data/graph-ml",
)

# Pick the fp16 file if it exists (shipped variant), else the fp64 one (dev).
FUSED_FNAME = (
    "fused_embeddings_fp16.npz"
    if os.path.exists(os.path.join(RARAS_APP_GRAPH_ML, "fused_embeddings_fp16.npz"))
    else "fused_embeddings.npz"
)
logger.info(f"gemeo.bridge: data dir={RARAS_APP_GRAPH_ML} fused={FUSED_FNAME}")

# In-process artifact cache — np.load(npz) is mmap-ish; we hold refs to keep arrays valid
_ARTIFACT_CACHE: dict = {}


def _path(name: str) -> str:
    return os.path.join(RARAS_APP_GRAPH_ML, name)


def has_raras_artifacts() -> bool:
    return all(
        os.path.exists(_path(f))
        for f in (FUSED_FNAME, "node_ids.json")
    )


@lru_cache(maxsize=1)
def load_node_ids() -> dict:
    """Returns {'disease': [orpha,...], 'phenotype': [hpo,...], 'gene': [symbol,...]}."""
    p = _path("node_ids.json")
    if not os.path.exists(p):
        logger.warning(f"node_ids.json not found at {p}")
        return {"disease": [], "phenotype": [], "gene": []}
    with open(p) as f:
        return json.load(f)


@lru_cache(maxsize=1)
def load_node_index() -> dict:
    """Inverted: {'disease': {orpha: idx}, 'phenotype': {hpo: idx}, 'gene': {symbol: idx}}."""
    ids = load_node_ids()
    return {
        kind: {nid: i for i, nid in enumerate(lst)}
        for kind, lst in ids.items()
    }


def load_fused_embeddings():
    """Returns dict: {'disease': np.ndarray, 'phenotype': np.ndarray, 'gene': np.ndarray} (3072-dim).

    Auto-detects fp16-quantized variant (`fused_embeddings_fp16.npz`,
    ~41 MB) or the original fp64 (`fused_embeddings.npz`, ~649 MB).
    The fp16 version is what ships in `gemeo/data/`; fp64 only exists
    in the dev workstation export from raras-app.
    """
    if "fused" in _ARTIFACT_CACHE:
        return _ARTIFACT_CACHE["fused"]
    p = _path(FUSED_FNAME)
    if not os.path.exists(p):
        logger.warning(f"{FUSED_FNAME} not found at {p}")
        return None
    try:
        import numpy as np
        npz = np.load(p)
        out = {k: npz[k] for k in npz.files}
        _ARTIFACT_CACHE["fused"] = out
        return out
    except Exception as e:
        logger.error(f"Failed to load fused embeddings: {e}")
        return None


def load_graph_embeddings():
    """64-dim PhenoGNet embeddings (lighter, for fast in-memory ops)."""
    if "graph" in _ARTIFACT_CACHE:
        return _ARTIFACT_CACHE["graph"]
    p = _path("graph_embeddings.npz")
    if not os.path.exists(p):
        return None
    try:
        import numpy as np
        npz = np.load(p)
        out = {k: npz[k] for k in npz.files}
        _ARTIFACT_CACHE["graph"] = out
        return out
    except Exception as e:
        logger.error(f"Failed to load graph embeddings: {e}")
        return None


@lru_cache(maxsize=1)
def load_hetero_graph() -> Optional[dict]:
    """The exported heterogeneous graph — node counts and edges by relation."""
    p = _path("hetero_graph.json")
    if not os.path.exists(p):
        return None
    try:
        with open(p) as f:
            return json.load(f)
    except Exception as e:
        logger.error(f"Failed to load hetero_graph.json: {e}")
        return None


def lookup_disease_embedding(orpha: str, kind: str = "fused"):
    emb = load_fused_embeddings() if kind == "fused" else load_graph_embeddings()
    if emb is None:
        return None
    idx = load_node_index().get("disease", {}).get(orpha)
    if idx is None:
        return None
    return emb["disease"][idx]


def lookup_phenotype_embedding(hpo: str, kind: str = "fused"):
    emb = load_fused_embeddings() if kind == "fused" else load_graph_embeddings()
    if emb is None:
        return None
    idx = load_node_index().get("phenotype", {}).get(hpo)
    if idx is None:
        return None
    return emb["phenotype"][idx]


def lookup_gene_embedding(symbol: str, kind: str = "fused"):
    emb = load_fused_embeddings() if kind == "fused" else load_graph_embeddings()
    if emb is None:
        return None
    idx = load_node_index().get("gene", {}).get(symbol)
    if idx is None:
        return None
    return emb["gene"][idx]


def stats() -> dict:
    """Diagnostic info for /api/gemeo/health."""
    out = {
        "graph_ml_dir": RARAS_APP_GRAPH_ML,
        "available": has_raras_artifacts(),
        "fused_loaded": "fused" in _ARTIFACT_CACHE,
        "graph_loaded": "graph" in _ARTIFACT_CACHE,
    }
    ids = load_node_ids()
    out["n_diseases"] = len(ids.get("disease", []))
    out["n_phenotypes"] = len(ids.get("phenotype", []))
    out["n_genes"] = len(ids.get("gene", []))
    fused = load_fused_embeddings()
    if fused is not None:
        out["fused_dim"] = int(fused["disease"].shape[1]) if "disease" in fused else 0
    return out