src/ai_processor.py

# smartheal_ai_processor.py
# Verbose, instrumented version — preserves public class/function names
# Turn on deep logging: export LOGLEVEL=DEBUG SMARTHEAL_DEBUG=1

import os
import logging
from datetime import datetime
from typing import Optional, Dict, List, Tuple

# ---- Environment defaults (do NOT globally hint CUDA here) ----
os.environ.setdefault("TOKENIZERS_PARALLELISM", "false")
LOGLEVEL = os.getenv("LOGLEVEL", "INFO").upper()
SMARTHEAL_DEBUG = os.getenv("SMARTHEAL_DEBUG", "0") == "1"

import cv2
import numpy as np
from PIL import Image
from PIL.ExifTags import TAGS

# --- Logging config ---
logging.basicConfig(
    level=getattr(logging, LOGLEVEL, logging.INFO),
    format="%(asctime)s - %(levelname)s - %(message)s",
)

def _log_kv(prefix: str, kv: Dict):
    logging.debug(prefix + " | " + " | ".join(f"{k}={v}" for k, v in kv.items()))

# --- Spaces GPU decorator (REQUIRED) ---
from spaces import GPU as _SPACES_GPU

@_SPACES_GPU(enable_queue=True)
def smartheal_gpu_stub(ping: int = 0) -> str:
    return "ready"

# ---- Paths / constants ----
UPLOADS_DIR = "uploads"
os.makedirs(UPLOADS_DIR, exist_ok=True)

HF_TOKEN = os.getenv("HF_TOKEN", None)
YOLO_MODEL_PATH = "src/best.pt"
SEG_MODEL_PATH = "src/segmentation_model.h5"   # optional; legacy .h5 supported
GUIDELINE_PDFS = ["src/eHealth in Wound Care.pdf", "src/IWGDF Guideline.pdf", "src/evaluation.pdf"]
DATASET_ID = "SmartHeal/wound-image-uploads"
DEFAULT_PX_PER_CM = 38.0
PX_PER_CM_MIN, PX_PER_CM_MAX = 5.0, 1200.0

# Segmentation preprocessing knobs
SEG_EXPECTS_RGB = os.getenv("SEG_EXPECTS_RGB", "1") == "1"  # most TF models trained on RGB
SEG_NORM = os.getenv("SEG_NORM", "0to1")                    # "0to1" | "imagenet"
SEG_THRESH = float(os.getenv("SEG_THRESH", "0.5"))

models_cache: Dict[str, object] = {}
knowledge_base_cache: Dict[str, object] = {}

# ---------- Utilities to prevent CUDA in main process ----------
from contextlib import contextmanager

@contextmanager
def _no_cuda_env():
    """
    Mask GPUs so any library imported/constructed in the main process
    cannot see CUDA (required for Spaces Stateless GPU).
    """
    prev = os.environ.get("CUDA_VISIBLE_DEVICES")
    os.environ["CUDA_VISIBLE_DEVICES"] = "-1"
    try:
        yield
    finally:
        if prev is None:
            os.environ.pop("CUDA_VISIBLE_DEVICES", None)
        else:
            os.environ["CUDA_VISIBLE_DEVICES"] = prev

# ---------- Lazy imports (wrapped where needed) ----------
def _import_ultralytics():
    # Prevent Ultralytics from probing CUDA on import
    with _no_cuda_env():
        from ultralytics import YOLO
    return YOLO

def _import_tf_loader():
    import tensorflow as tf
    tf.config.set_visible_devices([], "GPU")
    from tensorflow.keras.models import load_model
    return load_model

def _import_hf_cls():
    from transformers import pipeline
    return pipeline

def _import_embeddings():
    from langchain_community.embeddings import HuggingFaceEmbeddings
    return HuggingFaceEmbeddings

def _import_langchain_pdf():
    from langchain_community.document_loaders import PyPDFLoader
    return PyPDFLoader

def _import_langchain_faiss():
    from langchain_community.vectorstores import FAISS
    return FAISS

def _import_hf_hub():
    from huggingface_hub import HfApi, HfFolder
    return HfApi, HfFolder

# ---------- SmartHeal prompts (system + user prefix) ----------
SMARTHEAL_SYSTEM_PROMPT = """\
You are SmartHeal Clinical Assistant, a wound-care decision-support system.
You analyze wound photographs and brief patient context to produce careful,
specific, guideline-informed recommendations WITHOUT diagnosing. You always:
- Use the measurements calculated by the vision pipeline as ground truth.
- Prefer concise, actionable steps tailored to exudate level, infection risk, and pain.
- Flag uncertainties and red flags that need escalation to a clinician.
- Avoid contraindicated advice; do not infer unseen comorbidities.
- Keep under 300 words and use the requested headings exactly.
- Tone: professional, clear, and conservative; no definitive medical claims.
- Safety: remind the user to seek clinician review for changes or red flags.
"""

SMARTHEAL_USER_PREFIX = """\
Patient: {patient_info}
Visual findings: type={wound_type}, size={length_cm}x{breadth_cm} cm, area={area_cm2} cm^2,
detection_conf={det_conf:.2f}, calibration={px_per_cm} px/cm.
Guideline context (snippets you can draw principles from; do not quote at length):
{guideline_context}
Write a structured answer with these headings exactly:
1. Clinical Summary (max 4 bullet points)
2. Likely Stage/Type (if uncertain, say 'uncertain')
3. Treatment Plan (specific dressing choices and frequency based on exudate/infection risk)
4. Red Flags (what to escalate and when)
5. Follow-up Cadence (days)
6. Notes (assumptions/uncertainties)
Keep to 220–300 words. Do NOT provide diagnosis. Avoid contraindicated advice.
"""

# ---------- MedGemma-only text generator ----------
@_SPACES_GPU(enable_queue=True)
def _medgemma_generate_gpu(prompt: str, model_id: str, max_new_tokens: int, token: Optional[str]):
    """
    Runs entirely inside a Spaces GPU worker. Uses Med-Gemma (text-only) to draft the report.
    """
    import torch
    from transformers import pipeline

    pipe = pipeline(
        "image-text-to-text",
        model="google/medgemma-4b-it",
        torch_dtype=torch.bfloat16,
        device="cuda",
    )
    out = pipe(
        prompt,
        max_new_tokens=max_new_tokens,
        do_sample=False,
        temperature=0.2,
        return_full_text=True,
    )
    text = (out[0].get("generated_text") if isinstance(out, list) else out).strip()
    # Remove the prompt echo if present
    if text.startswith(prompt):
        text = text[len(prompt):].lstrip()
    return text or "⚠️ Empty response"

def generate_medgemma_report(  # kept name so callers don't change
    patient_info: str,
    visual_results: Dict,
    guideline_context: str,
    image_pil: Image.Image,  # kept for signature compatibility; not used by MedGemma
    max_new_tokens: Optional[int] = None,
) -> str:
    """
    MedGemma (text-only) report generation.
    The image is analyzed by the vision pipeline; MedGemma formats clinical guidance text.
    """
    if os.getenv("SMARTHEAL_ENABLE_VLM", "1") != "1":
        return "⚠️ VLM disabled"

    # Default to a public Med-Gemma instruction-tuned model (update via env if you have access to another).
    model_id = os.getenv("SMARTHEAL_MEDGEMMA_MODEL", "google/med-gemma-2-2b-it")
    max_new_tokens = max_new_tokens or int(os.getenv("SMARTHEAL_VLM_MAX_TOKENS", "600"))

    uprompt = SMARTHEAL_USER_PREFIX.format(
        patient_info=patient_info,
        wound_type=visual_results.get("wound_type", "Unknown"),
        length_cm=visual_results.get("length_cm", 0),
        breadth_cm=visual_results.get("breadth_cm", 0),
        area_cm2=visual_results.get("surface_area_cm2", 0),
        det_conf=float(visual_results.get("detection_confidence", 0.0)),
        px_per_cm=visual_results.get("px_per_cm", "?"),
        guideline_context=(guideline_context or "")[:900],
    )

    # Compose a single text prompt
    prompt = f"{SMARTHEAL_SYSTEM_PROMPT}\n\n{uprompt}\n\nAnswer:"

    try:
        return _medgemma_generate_gpu(prompt, model_id, max_new_tokens, HF_TOKEN)
    except Exception as e:
        logging.error(f"MedGemma call failed: {e}")
        return "⚠️ VLM error"

# ---------- Input-shape helpers (avoid `.as_list()` on strings) ----------
def _shape_to_hw(shape) -> Tuple[Optional[int], Optional[int]]:
    try:
        if hasattr(shape, "as_list"):
            shape = shape.as_list()
    except Exception:
        pass
    if isinstance(shape, (tuple, list)):
        if len(shape) == 4:   # (None, H, W, C)
            H, W = shape[1], shape[2]
        elif len(shape) == 3: # (H, W, C)
            H, W = shape[0], shape[1]
        else:
            return (None, None)
        try: H = int(H) if (H is not None and str(H).lower() != "none") else None
        except Exception: H = None
        try: W = int(W) if (W is not None and str(W).lower() != "none") else None
        except Exception: W = None
        return (H, W)
    return (None, None)

def _get_model_input_hw(model, default_hw: Tuple[int, int] = (224, 224)) -> Tuple[int, int]:
    H, W = _shape_to_hw(getattr(model, "input_shape", None))
    if H and W:
        return H, W
    try:
        inputs = getattr(model, "inputs", None)
        if inputs:
            H, W = _shape_to_hw(inputs[0].shape)
            if H and W:
                return H, W
    except Exception:
        pass
    try:
        cfg = model.get_config() if hasattr(model, "get_config") else None
        if isinstance(cfg, dict):
            for layer in cfg.get("layers", []):
                conf = (layer or {}).get("config", {})
                cand = conf.get("batch_input_shape") or conf.get("batch_shape")
                H, W = _shape_to_hw(cand)
                if H and W:
                    return H, W
    except Exception:
        pass
    logging.warning(f"Could not resolve model input shape; using default {default_hw}.")
    return default_hw

# ---------- Initialize CPU models ----------
def load_yolo_model():
    YOLO = _import_ultralytics()
    with _no_cuda_env():
        model = YOLO(YOLO_MODEL_PATH)
    return model

def load_segmentation_model(path: Optional[str] = None):
    """
    Robust loader for legacy .h5 models across TF/Keras versions.
    Uses global SEG_MODEL_PATH by default.
    """
    import ast
    import tensorflow as tf
    tf.config.set_visible_devices([], "GPU")
    model_path = path or SEG_MODEL_PATH

    # Attempt 1: tf.keras with safe_mode=False
    try:
        m = tf.keras.models.load_model(model_path, compile=False, safe_mode=False)
        logging.info("✅ Segmentation model loaded (tf.keras, safe_mode=False).")
        return m
    except Exception as e1:
        logging.warning(f"tf.keras load (safe_mode=False) failed: {e1}")

    # Attempt 2: patched InputLayer (drop legacy args; coerce string shapes)
    try:
        from tensorflow.keras.layers import InputLayer as _KInputLayer
        def _InputLayerPatched(*args, **kwargs):
            kwargs.pop("batch_shape", None)
            kwargs.pop("batch_input_shape", None)
            if "shape" in kwargs and isinstance(kwargs["shape"], str):
                try:
                    kwargs["shape"] = tuple(ast.literal_eval(kwargs["shape"]))
                except Exception:
                    kwargs.pop("shape", None)
            return _KInputLayer(**kwargs)
        m = tf.keras.models.load_model(
            model_path,
            compile=False,
            custom_objects={"InputLayer": _InputLayerPatched},
            safe_mode=False,
        )
        logging.info("✅ Segmentation model loaded (patched InputLayer).")
        return m
    except Exception as e2:
        logging.warning(f"Patched InputLayer load failed: {e2}")

    # Attempt 3: keras 2 shim (tf_keras) if present
    try:
        import tf_keras
        m = tf_keras.models.load_model(model_path, compile=False)
        logging.info("✅ Segmentation model loaded (tf_keras compat).")
        return m
    except Exception as e3:
        logging.warning(f"tf_keras load failed or not installed: {e3}")

    raise RuntimeError("Segmentation model could not be loaded; please convert/resave the model.")

def load_classification_pipeline():
    pipe = _import_hf_cls()
    return pipe("image-classification", model="Hemg/Wound-classification", token=HF_TOKEN, device="cpu")

def load_embedding_model():
    Emb = _import_embeddings()
    return Emb(model_name="sentence-transformers/all-MiniLM-L6-v2", model_kwargs={"device": "cpu"})

def initialize_cpu_models() -> None:
    if HF_TOKEN:
        try:
            HfApi, HfFolder = _import_hf_hub()
            HfFolder.save_token(HF_TOKEN)
            logging.info("✅ HF token set")
        except Exception as e:
            logging.warning(f"HF token save failed: {e}")

    if "det" not in models_cache:
        try:
            models_cache["det"] = load_yolo_model()
            logging.info("✅ YOLO loaded (CPU; CUDA masked in main)")
        except Exception as e:
            logging.error(f"YOLO load failed: {e}")

    if "seg" not in models_cache:
        try:
            if os.path.exists(SEG_MODEL_PATH):
                m = load_segmentation_model()  # uses global path by default
                models_cache["seg"] = m
                th, tw = _get_model_input_hw(m, default_hw=(224, 224))
                oshape = getattr(m, "output_shape", None)
                logging.info(f"✅ Segmentation model loaded (CPU) | input_hw=({th},{tw}) output_shape={oshape}")
            else:
                models_cache["seg"] = None
                logging.warning("Segmentation model file missing; skipping.")
        except Exception as e:
            models_cache["seg"] = None
            logging.warning(f"Segmentation unavailable: {e}")

    if "cls" not in models_cache:
        try:
            models_cache["cls"] = load_classification_pipeline()
            logging.info("✅ Classifier loaded (CPU)")
        except Exception as e:
            models_cache["cls"] = None
            logging.warning(f"Classifier unavailable: {e}")

    if "embedding_model" not in models_cache:
        try:
            models_cache["embedding_model"] = load_embedding_model()
            logging.info("✅ Embeddings loaded (CPU)")
        except Exception as e:
            models_cache["embedding_model"] = None
            logging.warning(f"Embeddings unavailable: {e}")

def setup_knowledge_base() -> None:
    if "vector_store" in knowledge_base_cache:
        return
    docs: List = []
    try:
        PyPDFLoader = _import_langchain_pdf()
        for pdf in GUIDELINE_PDFS:
            if os.path.exists(pdf):
                try:
                    docs.extend(PyPDFLoader(pdf).load())
                    logging.info(f"Loaded PDF: {pdf}")
                except Exception as e:
                    logging.warning(f"PDF load failed ({pdf}): {e}")
    except Exception as e:
        logging.warning(f"LangChain PDF loader unavailable: {e}")

    if docs and models_cache.get("embedding_model"):
        try:
            from langchain.text_splitter import RecursiveCharacterTextSplitter
            FAISS = _import_langchain_faiss()
            chunks = RecursiveCharacterTextSplitter(chunk_size=1000, chunk_overlap=100).split_documents(docs)
            knowledge_base_cache["vector_store"] = FAISS.from_documents(chunks, models_cache["embedding_model"])
            logging.info(f"✅ Knowledge base ready ({len(chunks)} chunks)")
        except Exception as e:
            knowledge_base_cache["vector_store"] = None
            logging.warning(f"KB build failed: {e}")
    else:
        knowledge_base_cache["vector_store"] = None
        logging.warning("KB disabled (no docs or embeddings).")

initialize_cpu_models()
setup_knowledge_base()

# ---------- Calibration helpers ----------
def _exif_to_dict(pil_img: Image.Image) -> Dict[str, object]:
    out = {}
    try:
        exif = pil_img.getexif()
        if not exif:
            return out
        for k, v in exif.items():
            tag = TAGS.get(k, k)
            out[tag] = v
    except Exception:
        pass
    return out

def _to_float(val) -> Optional[float]:
    try:
        if val is None:
            return None
        if isinstance(val, tuple) and len(val) == 2:
            num, den = float(val[0]), float(val[1]) if float(val[1]) != 0 else 1.0
            return num / den
        return float(val)
    except Exception:
        return None

def _estimate_sensor_width_mm(f_mm: Optional[float], f35: Optional[float]) -> Optional[float]:
    if f_mm and f35 and f35 > 0:
        return 36.0 * f_mm / f35
    return None

def estimate_px_per_cm_from_exif(pil_img: Image.Image, default_px_per_cm: float = DEFAULT_PX_PER_CM) -> Tuple[float, Dict]:
    meta = {"used": "default", "f_mm": None, "f35": None, "sensor_w_mm": None, "distance_m": None}
    try:
        exif = _exif_to_dict(pil_img)
        f_mm = _to_float(exif.get("FocalLength"))
        f35 = _to_float(exif.get("FocalLengthIn35mmFilm") or exif.get("FocalLengthIn35mm"))
        subj_dist_m = _to_float(exif.get("SubjectDistance"))
        sensor_w_mm = _estimate_sensor_width_mm(f_mm, f35)
        meta.update({"f_mm": f_mm, "f35": f35, "sensor_w_mm": sensor_w_mm, "distance_m": subj_dist_m})

        if f_mm and sensor_w_mm and subj_dist_m and subj_dist_m > 0:
            w_px = pil_img.width
            field_w_mm = sensor_w_mm * (subj_dist_m * 1000.0) / f_mm
            field_w_cm = field_w_mm / 10.0
            px_per_cm = w_px / max(field_w_cm, 1e-6)
            px_per_cm = float(np.clip(px_per_cm, PX_PER_CM_MIN, PX_PER_CM_MAX))
            meta["used"] = "exif"
            return px_per_cm, meta
        return float(default_px_per_cm), meta
    except Exception:
        return float(default_px_per_cm), meta

# ---------- Segmentation helpers ----------
def _imagenet_norm(arr: np.ndarray) -> np.ndarray:
    mean = np.array([123.675, 116.28, 103.53], dtype=np.float32)
    std  = np.array([58.395, 57.12, 57.375], dtype=np.float32)
    return (arr.astype(np.float32) - mean) / std

def _preprocess_for_seg(bgr_roi: np.ndarray, target_hw: Tuple[int, int]) -> np.ndarray:
    H, W = target_hw
    resized = cv2.resize(bgr_roi, (W, H), interpolation=cv2.INTER_LINEAR)
    if SEG_EXPECTS_RGB:
        resized = cv2.cvtColor(resized, cv2.COLOR_BGR2RGB)
    if SEG_NORM.lower() == "imagenet":
        x = _imagenet_norm(resized)
    else:
        x = resized.astype(np.float32) / 255.0
    x = np.expand_dims(x, axis=0)  # (1,H,W,3)
    return x

def _to_prob(pred: np.ndarray) -> np.ndarray:
    p = np.squeeze(pred)
    pmin, pmax = float(p.min()), float(p.max())
    if pmax > 1.0 or pmin < 0.0:
        p = 1.0 / (1.0 + np.exp(-p))
    return p.astype(np.float32)

# ---- Adaptive threshold + GrabCut grow ----
def _adaptive_prob_threshold(p: np.ndarray) -> float:
    """
    Choose a threshold that avoids tiny blobs while not swallowing skin.
    Try Otsu and the 90th percentile, clamp to [0.25, 0.65], pick by area heuristic.
    """
    p01 = np.clip(p.astype(np.float32), 0, 1)
    p255 = (p01 * 255).astype(np.uint8)

    ret_otsu, _ = cv2.threshold(p255, 0, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)
    thr_otsu = float(np.clip(ret_otsu / 255.0, 0.25, 0.65))
    thr_pctl = float(np.clip(np.percentile(p01, 90), 0.25, 0.65))

    def area_frac(thr: float) -> float:
        return float((p01 >= thr).sum()) / float(p01.size)

    af_otsu = area_frac(thr_otsu)
    af_pctl = area_frac(thr_pctl)

    def score(af: float) -> float:
        target_low, target_high = 0.03, 0.10
        if af < target_low: return abs(af - target_low) * 3.0
        if af > target_high: return abs(af - target_high) * 1.5
        return 0.0

    return thr_otsu if score(af_otsu) <= score(af_pctl) else thr_pctl

def _grabcut_refine(bgr: np.ndarray, seed01: np.ndarray, iters: int = 3) -> np.ndarray:
    """Grow from a confident core into low-contrast margins."""
    h, w = bgr.shape[:2]
    gc = np.full((h, w), cv2.GC_PR_BGD, np.uint8)
    k = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (5, 5))
    seed_dil = cv2.dilate(seed01, k, iterations=1)
    gc[seed01.astype(bool)] = cv2.GC_PR_FGD
    gc[seed_dil.astype(bool)] = cv2.GC_FGD
    gc[0, :], gc[-1, :], gc[:, 0], gc[:, 1] = cv2.GC_BGD, cv2.GC_BGD, cv2.GC_BGD, cv2.GC_BGD
    bgdModel = np.zeros((1, 65), np.float64)
    fgdModel = np.zeros((1, 65), np.float64)
    cv2.grabCut(bgr, gc, None, bgdModel, fgdModel, iters, cv2.GC_INIT_WITH_MASK)
    return np.where((gc == cv2.GC_FGD) | (gc == cv2.GC_PR_FGD), 1, 0).astype(np.uint8)

def _fill_holes(mask01: np.ndarray) -> np.ndarray:
    h, w = mask01.shape[:2]
    ff = np.zeros((h + 2, w + 2), np.uint8)
    m = (mask01 * 255).astype(np.uint8).copy()
    cv2.floodFill(m, ff, (0, 0), 255)
    m_inv = cv2.bitwise_not(m)
    out = ((mask01 * 255) | m_inv) // 255
    return out.astype(np.uint8)

def _clean_mask(mask01: np.ndarray) -> np.ndarray:
    """Open → Close → Fill holes → Largest component (no dilation)."""
    mask01 = (mask01 > 0).astype(np.uint8)
    k3 = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (3, 3))
    k5 = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (5, 5))
    mask01 = cv2.morphologyEx(mask01, cv2.MORPH_OPEN, k3, iterations=1)
    mask01 = cv2.morphologyEx(mask01, cv2.MORPH_CLOSE, k5, iterations=1)
    mask01 = _fill_holes(mask01)
    # Keep largest component only
    num, labels, stats, _ = cv2.connectedComponentsWithStats(mask01, 8)
    if num > 1:
        areas = stats[1:, cv2.CC_STAT_AREA]
        if areas.size:
            largest_idx = 1 + int(np.argmax(areas))
            mask01 = (labels == largest_idx).astype(np.uint8)
    return (mask01 > 0).astype(np.uint8)

# Global last debug dict (per-process)
_last_seg_debug: Dict[str, object] = {}

def segment_wound(image_bgr: np.ndarray, ts: str, out_dir: str) -> Tuple[np.ndarray, Dict[str, object]]:
    """
    TF model → adaptive threshold on prob → GrabCut grow → cleanup.
    Fallback: KMeans-Lab.
    Returns (mask_uint8_0_255, debug_dict)
    """
    debug = {"used": None, "reason": None, "positive_fraction": 0.0,
             "thr": None, "heatmap_path": None, "roi_seen_by_model": None}

    seg_model = models_cache.get("seg", None)

    # --- Model path ---
    if seg_model is not None:
        try:
            th, tw = _get_model_input_hw(seg_model, default_hw=(224, 224))
            x = _preprocess_for_seg(image_bgr, (th, tw))
            roi_seen_path = None
            if SMARTHEAL_DEBUG:
                roi_seen_path = os.path.join(out_dir, f"roi_for_seg_{ts}.png")
                cv2.imwrite(roi_seen_path, image_bgr)

            pred = seg_model.predict(x, verbose=0)
            if isinstance(pred, (list, tuple)): pred = pred[0]
            p = _to_prob(pred)
            p = cv2.resize(p, (image_bgr.shape[1], image_bgr.shape[0]), interpolation=cv2.INTER_LINEAR)

            heatmap_path = None
            if SMARTHEAL_DEBUG:
                hm = (np.clip(p, 0, 1) * 255).astype(np.uint8)
                heat = cv2.applyColorMap(hm, cv2.COLORMAP_JET)
                heatmap_path = os.path.join(out_dir, f"seg_pred_heatmap_{ts}.png")
                cv2.imwrite(heatmap_path, heat)

            thr = _adaptive_prob_threshold(p)
            core01 = (p >= thr).astype(np.uint8)
            core_frac = float(core01.sum()) / float(core01.size)

            if core_frac < 0.005:
                thr2 = max(thr - 0.10, 0.15)
                core01 = (p >= thr2).astype(np.uint8)
                thr = thr2
                core_frac = float(core01.sum()) / float(core01.size)

            if core01.any():
                gc01 = _grabcut_refine(image_bgr, core01, iters=3)
                mask01 = _clean_mask(gc01)
            else:
                mask01 = np.zeros(core01.shape, np.uint8)

            pos_frac = float(mask01.sum()) / float(mask01.size)
            logging.info(f"SegModel USED | thr={float(thr):.2f} core_frac={core_frac:.4f} final_frac={pos_frac:.4f}")

            debug.update({
                "used": "tf_model",
                "reason": "ok",
                "positive_fraction": pos_frac,
                "thr": float(thr),
                "heatmap_path": heatmap_path,
                "roi_seen_by_model": roi_seen_path
            })
            return (mask01 * 255).astype(np.uint8), debug

        except Exception as e:
            logging.warning(f"⚠️ Segmentation model failed → fallback. Reason: {e}")
            debug.update({"used": "fallback_kmeans", "reason": f"model_failed: {e}"})

    # --- Fallback: KMeans in Lab (reddest cluster as wound) ---
    Z = image_bgr.reshape((-1, 3)).astype(np.float32)
    criteria = (cv2.TERM_CRITERIA_EPS + cv2.TERM_CRITERIA_MAX_ITER, 10, 1.0)
    _, labels, centers = cv2.kmeans(Z, 2, None, criteria, 5, cv2.KMEANS_PP_CENTERS)
    centers_u8 = centers.astype(np.uint8).reshape(1, 2, 3)
    centers_lab = cv2.cvtColor(centers_u8, cv2.COLOR_BGR2LAB)[0]
    wound_idx = int(np.argmax(centers_lab[:, 1]))  # maximize a* (red)
    mask01 = (labels.reshape(image_bgr.shape[:2]) == wound_idx).astype(np.uint8)
    mask01 = _clean_mask(mask01)

    pos_frac = float(mask01.sum()) / float(mask01.size)
    logging.info(f"KMeans USED | final_frac={pos_frac:.4f}")

    debug.update({
        "used": "fallback_kmeans",
        "reason": debug.get("reason") or "no_model",
        "positive_fraction": pos_frac,
        "thr": None
    })
    return (mask01 * 255).astype(np.uint8), debug

# ---------- Measurement + overlay helpers ----------
def largest_component_mask(binary01: np.ndarray, min_area_px: int = 50) -> np.ndarray:
    num, labels, stats, _ = cv2.connectedComponentsWithStats(binary01.astype(np.uint8), connectivity=8)
    if num <= 1:
        return binary01.astype(np.uint8)
    areas = stats[1:, cv2.CC_STAT_AREA]
    if areas.size == 0 or areas.max() < min_area_px:
        return binary01.astype(np.uint8)
    largest_idx = 1 + int(np.argmax(areas))
    return (labels == largest_idx).astype(np.uint8)

def measure_min_area_rect(mask01: np.ndarray, px_per_cm: float) -> Tuple[float, float, Tuple]:
    contours, _ = cv2.findContours(mask01.astype(np.uint8), cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    if not contours:
        return 0.0, 0.0, (None, None)
    cnt = max(contours, key=cv2.contourArea)
    rect = cv2.minAreaRect(cnt)
    (w_px, h_px) = rect[1]
    length_px, breadth_px = (max(w_px, h_px), min(h_px, w_px))
    length_cm = round(length_px / max(px_per_cm, 1e-6), 2)
    breadth_cm = round(breadth_px / max(px_per_cm, 1e-6), 2)
    box = cv2.boxPoints(rect).astype(int)
    return length_cm, breadth_cm, (box, rect[0])

def area_cm2_from_contour(mask01: np.ndarray, px_per_cm: float) -> Tuple[float, Optional[np.ndarray]]:
    """Area from largest polygon (sub-pixel); returns (area_cm2, contour)."""
    m = (mask01 > 0).astype(np.uint8)
    contours, _ = cv2.findContours(m, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    if not contours:
        return 0.0, None
    cnt = max(contours, key=cv2.contourArea)
    poly_area_px2 = float(cv2.contourArea(cnt))
    area_cm2 = round(poly_area_px2 / (max(px_per_cm, 1e-6) ** 2), 2)
    return area_cm2, cnt

def clamp_area_with_minrect(cnt: np.ndarray, px_per_cm: float, area_cm2_poly: float) -> float:
    rect = cv2.minAreaRect(cnt)
    (w_px, h_px) = rect[1]
    rect_area_px2 = float(max(w_px, 0.0) * max(h_px, 0.0))
    rect_area_cm2 = rect_area_px2 / (max(px_per_cm, 1e-6) ** 2)
    return round(min(area_cm2_poly, rect_area_cm2 * 1.05), 2)

def draw_measurement_overlay(
    base_bgr: np.ndarray,
    mask01: np.ndarray,
    rect_box: np.ndarray,
    length_cm: float,
    breadth_cm: float,
    thickness: int = 2
) -> np.ndarray:
    """
    1) Strong red mask overlay + white contour
    2) Min-area rectangle
    3) Double-headed arrows labeled Length/Width
    """
    overlay = base_bgr.copy()

    # Mask tint
    mask255 = (mask01 * 255).astype(np.uint8)
    mask3 = cv2.merge([mask255, mask255, mask255])
    red = np.zeros_like(overlay); red[:] = (0, 0, 255)
    alpha = 0.55
    tinted = cv2.addWeighted(overlay, 1 - alpha, red, alpha, 0)
    overlay = np.where(mask3 > 0, tinted, overlay)

    # Contour
    cnts, _ = cv2.findContours(mask255, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    if cnts:
        cv2.drawContours(overlay, cnts, -1, (255, 255, 255), 2)

    if rect_box is not None:
        cv2.polylines(overlay, [rect_box], True, (255, 255, 255), thickness)
        pts = rect_box.reshape(-1, 2)

        def midpoint(a, b): return (int((a[0] + b[0]) / 2), int((a[1] + b[1]) / 2))
        e = [np.linalg.norm(pts[i] - pts[(i + 1) % 4]) for i in range(4)]
        long_edge_idx = int(np.argmax(e))
        mids = [midpoint(pts[i], pts[(i + 1) % 4]) for i in range(4)]
        long_pair = (long_edge_idx, (long_edge_idx + 2) % 4)
        short_pair = ((long_edge_idx + 1) % 4, (long_edge_idx + 3) % 4)

        def draw_double_arrow(img, p1, p2):
            cv2.arrowedLine(img, p1, p2, (0, 0, 0), thickness + 2, tipLength=0.05)
            cv2.arrowedLine(img, p2, p1, (0, 0, 0), thickness + 2, tipLength=0.05)
            cv2.arrowedLine(img, p1, p2, (255, 255, 255), thickness, tipLength=0.05)
            cv2.arrowedLine(img, p2, p1, (255, 255, 255), thickness, tipLength=0.05)

        def put_label(text, anchor):
            org = (anchor[0] + 6, anchor[1] - 6)
            cv2.putText(overlay, text, org, cv2.FONT_HERSHEY_SIMPLEX, 0.7, (0, 0, 0), 4, cv2.LINE_AA)
            cv2.putText(overlay, text, org, cv2.FONT_HERSHEY_SIMPLEX, 0.7, (255, 255, 255), 2, cv2.LINE_AA)

        draw_double_arrow(overlay, mids[long_pair[0]], mids[long_pair[1]])
        draw_double_arrow(overlay, mids[short_pair[0]], mids[short_pair[1]])
        put_label(f"Length: {length_cm:.2f} cm", mids[long_pair[0]])
        put_label(f"Width:  {breadth_cm:.2f} cm", mids[short_pair[0]])

    return overlay

# ---------- AI PROCESSOR ----------
class AIProcessor:
    def __init__(self):
        self.models_cache = models_cache
        self.knowledge_base_cache = knowledge_base_cache
        self.uploads_dir = UPLOADS_DIR
        self.dataset_id = DATASET_ID
        self.hf_token = HF_TOKEN

    def _ensure_analysis_dir(self) -> str:
        out_dir = os.path.join(self.uploads_dir, "analysis")
        os.makedirs(out_dir, exist_ok=True)
        return out_dir

    def perform_visual_analysis(self, image_pil: Image.Image) -> Dict:
        """
        YOLO detect → crop ROI → segment_wound(ROI) → clean mask →
        minAreaRect measurement (cm) using EXIF px/cm → save outputs.
        """
        try:
            px_per_cm, exif_meta = estimate_px_per_cm_from_exif(image_pil, DEFAULT_PX_PER_CM)
            # Guardrails for calibration to avoid huge area blow-ups
            px_per_cm = float(np.clip(px_per_cm, 20.0, 350.0))
            if (exif_meta or {}).get("used") != "exif":
                logging.warning(f"Calibration fallback used: px_per_cm={px_per_cm:.2f} (default). Prefer ruler/Aruco for accuracy.")

            image_cv = cv2.cvtColor(np.array(image_pil.convert("RGB")), cv2.COLOR_RGB2BGR)

            # --- Detection ---
            det_model = self.models_cache.get("det")
            if det_model is None:
                raise RuntimeError("YOLO model not loaded")
            # Force CPU inference and avoid CUDA touch
            results = det_model.predict(image_cv, verbose=False, device="cpu")
            if (not results) or (not getattr(results[0], "boxes", None)) or (len(results[0].boxes) == 0):
                try:
                    import gradio as gr
                    raise gr.Error("No wound could be detected.")
                except Exception:
                    raise RuntimeError("No wound could be detected.")

            box = results[0].boxes[0].xyxy[0].cpu().numpy().astype(int)
            x1, y1, x2, y2 = [int(v) for v in box]
            x1, y1 = max(0, x1), max(0, y1)
            x2, y2 = min(image_cv.shape[1], x2), min(image_cv.shape[0], y2)
            roi = image_cv[y1:y2, x1:x2].copy()
            if roi.size == 0:
                try:
                    import gradio as gr
                    raise gr.Error("Detected ROI is empty.")
                except Exception:
                    raise RuntimeError("Detected ROI is empty.")

            out_dir = self._ensure_analysis_dir()
            ts = datetime.now().strftime("%Y%m%d_%H%M%S")

            # --- Segmentation (model-first + KMeans fallback) ---
            mask_u8_255, seg_debug = segment_wound(roi, ts, out_dir)
            mask01 = (mask_u8_255 > 127).astype(np.uint8)

            if mask01.any():
                mask01 = _clean_mask(mask01)
                logging.debug(f"Mask postproc: px_after={int(mask01.sum())}")

            # --- Measurement (accurate & conservative) ---
            if mask01.any():
                length_cm, breadth_cm, (box_pts, _) = measure_min_area_rect(mask01, px_per_cm)
                area_poly_cm2, largest_cnt = area_cm2_from_contour(mask01, px_per_cm)
                if largest_cnt is not None:
                    surface_area_cm2 = clamp_area_with_minrect(largest_cnt, px_per_cm, area_poly_cm2)
                else:
                    surface_area_cm2 = area_poly_cm2

                anno_roi = draw_measurement_overlay(roi, mask01, box_pts, length_cm, breadth_cm)
                segmentation_empty = False
            else:
                # Fallback if seg failed: use ROI dimensions
                h_px = max(0, y2 - y1); w_px = max(0, x2 - x1)
                length_cm = round(max(h_px, w_px) / px_per_cm, 2)
                breadth_cm = round(min(h_px, w_px) / px_per_cm, 2)
                surface_area_cm2 = round((h_px * w_px) / (px_per_cm ** 2), 2)
                anno_roi = roi.copy()
                cv2.rectangle(anno_roi, (2, 2), (anno_roi.shape[1]-3, anno_roi.shape[0]-3), (0, 0, 255), 3)
                cv2.line(anno_roi, (0, 0), (anno_roi.shape[1]-1, anno_roi.shape[0]-1), (0, 0, 255), 2)
                cv2.line(anno_roi, (anno_roi.shape[1]-1, 0), (0, anno_roi.shape[0]-1), (0, 0, 255), 2)
                box_pts = None
                segmentation_empty = True

            # --- Save visualizations ---
            original_path = os.path.join(out_dir, f"original_{ts}.png")
            cv2.imwrite(original_path, image_cv)

            det_vis = image_cv.copy()
            cv2.rectangle(det_vis, (x1, y1), (x2, y2), (0, 255, 0), 2)
            detection_path = os.path.join(out_dir, f"detection_{ts}.png")
            cv2.imwrite(detection_path, det_vis)

            roi_mask_path = os.path.join(out_dir, f"roi_mask_{ts}.png")
            cv2.imwrite(roi_mask_path, (mask01 * 255).astype(np.uint8))

            # ROI overlay (mask tint + contour, without arrows)
            mask255 = (mask01 * 255).astype(np.uint8)
            mask3   = cv2.merge([mask255, mask255, mask255])
            red     = np.zeros_like(roi); red[:] = (0, 0, 255)
            alpha   = 0.55
            tinted  = cv2.addWeighted(roi, 1 - alpha, red, alpha, 0)
            if mask255.any():
                roi_overlay = np.where(mask3 > 0, tinted, roi)
                cnts, _ = cv2.findContours(mask255, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
                cv2.drawContours(roi_overlay, cnts, -1, (255, 255, 255), 2)
            else:
                roi_overlay = anno_roi

            seg_full = image_cv.copy()
            seg_full[y1:y2, x1:x2] = roi_overlay
            segmentation_path = os.path.join(out_dir, f"segmentation_{ts}.png")
            cv2.imwrite(segmentation_path, seg_full)

            segmentation_roi_path = os.path.join(out_dir, f"segmentation_roi_{ts}.png")
            cv2.imwrite(segmentation_roi_path, roi_overlay)

            # Annotated (mask + arrows + labels) in full-frame
            anno_full = image_cv.copy()
            anno_full[y1:y2, x1:x2] = anno_roi
            annotated_seg_path = os.path.join(out_dir, f"segmentation_annotated_{ts}.png")
            cv2.imwrite(annotated_seg_path, anno_full)

            # --- Optional classification ---
            wound_type = "Unknown"
            cls_pipe = self.models_cache.get("cls")
            if cls_pipe is not None:
                try:
                    preds = cls_pipe(Image.fromarray(cv2.cvtColor(roi, cv2.COLOR_BGR2RGB)))
                    if preds:
                        wound_type = max(preds, key=lambda x: x.get("score", 0)).get("label", "Unknown")
                except Exception as e:
                    logging.warning(f"Classification failed: {e}")

            # Log end-of-seg summary
            seg_summary = {
                "seg_used": seg_debug.get("used"),
                "seg_reason": seg_debug.get("reason"),
                "positive_fraction": round(float(seg_debug.get("positive_fraction", 0.0)), 6),
                "threshold": seg_debug.get("thr"),
                "segmentation_empty": segmentation_empty,
                "exif_px_per_cm": round(px_per_cm, 3),
            }
            _log_kv("SEG_SUMMARY", seg_summary)

            return {
                "wound_type": wound_type,
                "length_cm": length_cm,
                "breadth_cm": breadth_cm,
                "surface_area_cm2": surface_area_cm2,
                "px_per_cm": round(px_per_cm, 2),
                "calibration_meta": exif_meta,
                "detection_confidence": float(results[0].boxes.conf[0].cpu().item())
                    if getattr(results[0].boxes, "conf", None) is not None else 0.0,
                "detection_image_path": detection_path,
                "segmentation_image_path": annotated_seg_path,
                "segmentation_annotated_path": annotated_seg_path,
                "segmentation_roi_path": segmentation_roi_path,
                "roi_mask_path": roi_mask_path,
                "segmentation_empty": segmentation_empty,
                "segmentation_debug": seg_debug,
                "original_image_path": original_path,
            }
        except Exception as e:
            logging.error(f"Visual analysis failed: {e}", exc_info=True)
            raise

    # ---------- Knowledge base + reporting ----------
    def query_guidelines(self, query: str) -> str:
        try:
            vs = self.knowledge_base_cache.get("vector_store")
            if not vs:
                return "Knowledge base is not available."
            retriever = vs.as_retriever(search_kwargs={"k": 5})
            docs = retriever.invoke(query)
            lines: List[str] = []
            for d in docs:
                src = (d.metadata or {}).get("source", "N/A")
                txt = (d.page_content or "")[:300]
                lines.append(f"Source: {src}\nContent: {txt}...")
            return "\n\n".join(lines) if lines else "No relevant guideline snippets found."
        except Exception as e:
            logging.warning(f"Guidelines query failed: {e}")
            return f"Guidelines query failed: {str(e)}"

    def _generate_fallback_report(self, patient_info: str, visual_results: Dict, guideline_context: str) -> str:
        return f"""# 🩺 SmartHeal AI - Comprehensive Wound Analysis Report
## 📋 Patient Information
{patient_info}
## 🔍 Visual Analysis Results
- **Wound Type**: {visual_results.get('wound_type', 'Unknown')}
- **Dimensions**: {visual_results.get('length_cm', 0)} cm × {visual_results.get('breadth_cm', 0)} cm
- **Surface Area**: {visual_results.get('surface_area_cm2', 0)} cm²
- **Detection Confidence**: {visual_results.get('detection_confidence', 0):.1%}
- **Calibration**: {visual_results.get('px_per_cm','?')} px/cm ({(visual_results.get('calibration_meta') or {}).get('used','default')})
## 📊 Analysis Images
- **Original**: {visual_results.get('original_image_path', 'N/A')}
- **Detection**: {visual_results.get('detection_image_path', 'N/A')}
- **Segmentation**: {visual_results.get('segmentation_image_path', 'N/A')}
- **Annotated**: {visual_results.get('segmentation_annotated_path', 'N/A')}
## 🎯 Clinical Summary
Automated analysis provides quantitative measurements; verify via clinical examination.
## 💊 Recommendations
- Cleanse wound gently; select dressing per exudate/infection risk
- Debride necrotic tissue if indicated (clinical decision)
- Document with serial photos and measurements
## 📅 Monitoring
- Daily in week 1, then every 2–3 days (or as indicated)
- Weekly progress review
## 📚 Guideline Context
{(guideline_context or '')[:800]}{"..." if guideline_context and len(guideline_context) > 800 else ''}
**Disclaimer:** Automated, for decision support only. Verify clinically.
"""

    def generate_final_report(
        self,
        patient_info: str,
        visual_results: Dict,
        guideline_context: str,
        image_pil: Image.Image,
        max_new_tokens: Optional[int] = None,
    ) -> str:
        try:
            report = generate_medgemma_report(
                patient_info, visual_results, guideline_context, image_pil, max_new_tokens
            )
            if report and report.strip() and not report.startswith(("⚠️", "❌")):
                return report
            logging.warning("VLM unavailable/invalid; using fallback.")
            return self._generate_fallback_report(patient_info, visual_results, guideline_context)
        except Exception as e:
            logging.error(f"Report generation failed: {e}")
            return self._generate_fallback_report(patient_info, visual_results, guideline_context)

    def save_and_commit_image(self, image_pil: Image.Image) -> str:
        try:
            os.makedirs(self.uploads_dir, exist_ok=True)
            ts = datetime.now().strftime("%Y%m%d_%H%M%S")
            filename = f"{ts}.png"
            path = os.path.join(self.uploads_dir, filename)
            image_pil.convert("RGB").save(path)
            logging.info(f"✅ Image saved locally: {path}")

            if HF_TOKEN and DATASET_ID:
                try:
                    HfApi, HfFolder = _import_hf_hub()
                    HfFolder.save_token(HF_TOKEN)
                    api = HfApi()
                    api.upload_file(
                        path_or_fileobj=path,
                        path_in_repo=f"images/{filename}",
                        repo_id=DATASET_ID,
                        repo_type="dataset",
                        token=HF_TOKEN,
                        commit_message=f"Upload wound image: {filename}",
                    )
                    logging.info("✅ Image committed to HF dataset")
                except Exception as e:
                    logging.warning(f"HF upload failed: {e}")

            return path
        except Exception as e:
            logging.error(f"Failed to save/commit image: {e}")
            return ""

    def full_analysis_pipeline(self, image_pil: Image.Image, questionnaire_data: Dict) -> Dict:
        try:
            saved_path = self.save_and_commit_image(image_pil)
            visual_results = self.perform_visual_analysis(image_pil)

            pi = questionnaire_data or {}
            patient_info = (
                f"Age: {pi.get('age','N/A')}, "
                f"Diabetic: {pi.get('diabetic','N/A')}, "
                f"Allergies: {pi.get('allergies','N/A')}, "
                f"Date of Wound: {pi.get('date_of_injury','N/A')}, "
                f"Professional Care: {pi.get('professional_care','N/A')}, "
                f"Oozing/Bleeding: {pi.get('oozing_bleeding','N/A')}, "
                f"Infection: {pi.get('infection','N/A')}, "
                f"Moisture: {pi.get('moisture','N/A')}"
            )

            query = (
                f"best practices for managing a {visual_results.get('wound_type','Unknown')} "
                f"with moisture '{pi.get('moisture','unknown')}' and infection '{pi.get('infection','unknown')}' "
                f"in a diabetic status '{pi.get('diabetic','unknown')}'"
            )
            guideline_context = self.query_guidelines(query)

            report = self.generate_final_report(patient_info, visual_results, guideline_context, image_pil)

            return {
                "success": True,
                "visual_analysis": visual_results,
                "report": report,
                "saved_image_path": saved_path,
                "guideline_context": (guideline_context or "")[:500] + (
                    "..." if guideline_context and len(guideline_context) > 500 else ""
                ),
            }
        except Exception as e:
            logging.error(f"Pipeline error: {e}")
            return {
                "success": False,
                "error": str(e),
                "visual_analysis": {},
                "report": f"Analysis failed: {str(e)}",
                "saved_image_path": None,
                "guideline_context": "",
            }

    def analyze_wound(self, image, questionnaire_data: Dict) -> Dict:
        try:
            if isinstance(image, str):
                if not os.path.exists(image):
                    raise ValueError(f"Image file not found: {image}")
                image_pil = Image.open(image)
            elif isinstance(image, Image.Image):
                image_pil = image
            elif isinstance(image, np.ndarray):
                image_pil = Image.fromarray(image)
            else:
                raise ValueError(f"Unsupported image type: {type(image)}")

            return self.full_analysis_pipeline(image_pil, questionnaire_data or {})
        except Exception as e:
            logging.error(f"Wound analysis error: {e}")
            return {
                "success": False,
                "error": str(e),
                "visual_analysis": {},
                "report": f"Analysis initialization failed: {str(e)}",
                "saved_image_path": None,
                "guideline_context": "",
            }